Note: Descriptions are shown in the official language in which they were submitted.
~15i~
_1- Mo-~075
LeA 19,528
A PROCES~ ~CR TXE PRO~UCTION OF MODIFIED
POLYETH~R POLYOLS AND THEIR USE IN PROCESSES
FOR THE PRODUCTION OF POLYU~ETHANE PLASTICS
BACKGROUND OF THE INVENTIO~
S Polyether polyols modified by polymers or
copol~mers of olefinically unsaturated monomers, so-called
polymer polyols, and their use for the production of
polyurethane plastics, particularly foams, are known.
They are produced by the polymerization in situ of one
or more vinyl monomers in standard polyether polyols. The
use of acrylonitrile and mixtures thereof with styrene
ha-; ac~uired the greatest commercial significance,
in the presence of a radical-forming polymerization
initiator. The production and use of products such as
these are desc_ibed, for example, in U. S. Patents
3,3G4,273; 3,383,351; Re-28715; Re-29118; 3,523,093;
4,104,236; 4,111,865; 4,119,586; 4,125,505; 4,148,840 and
4,172,825; and in German Patents 1,222,669; 1,152,536
and 1,152,537.
Polyurethanes produced with polymer polyols
of this type are distinguished by an improvement of
their properties. In particular, the hardness and load
bearing strength of fle~ible polyurethane foams are
favorably influenced. ~herefore it is possible to
obtain relatively low densities and, thus, to save
on starting material for the same level of hardness and
tearing strength of previous polyurethanes.
In addition, the polymer polyols provide
fleY~ible foams with a greater open-cell character and,
in doins so, counteract shrinkage of the fresh foams
during storage. Finally, it is possible by means of
the polymer polyols, provided that the starting polyether
is suitably selected, to produce so-called highly
elastic, col~-hardening foams~ In contrast to
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con~entional processes for producing foams such as these,
there is no need to use ~pecial polyisocyanates with
adapted reactivity;instead it is possible to use
standard commercial products, particularly the tolylene
diisocyanate predominantly used in the production of
flexible foams.
Ideally, the polymer poly~ls are relatively
low-viscosity, finely divided, non-sedimenting
dispersions of the polymer, preferably an acrylonitrile
or acrylonitrile/styrene graft (co) polymer, in the
substantially unchanged polyether polyol. Characteristic
features of the quality and processibility of the polymer
polyols are 'o~ viscosity, stability in storage (resistance
to sedimentation) and particle size. These properties
are influenced primarily by the type of starting materials
used and by the quantit~tive ratios between them.
For monomer mixtures o~ acrylonitrile and styrene,
optionally together with small quantities of other co-
monomers, the optLmum properties of the polymer polyol
(as low a viscosity as po~sible; absence of sediment
and agglomerate;small particle size), for a given
molecular weight of the starting polyether~ lies within a
relatively narrow range of production parameters. The
monomer content of the mixture and the monomer ratio
both have a particularly marked influence upon the
quality of the end product~ Starting out from a polymeriz-
ation mixture containing pure acrylonitrile, the viscosity,
particle size and ag~lomerate content pass through a
minimum with increasing styrene content of the mixture
and rise sharply with increasing styrene content beyond
this minimum. They also increase drastically with in-
creasing monomer total, based on the starting polyether.
~owe~e-, the abovementioned ~zlues also i~creas~ wi~h
decreasing molecular weight o~ the starting polyether
and also with a reduction in ~he polymerization tempe-
rature to below 100 C.
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The polymer polyol dispersions are stabilized
against sedimentation by the incorporaticn of some of
the molecules of the starting polyether into the polymer
formed ln situ. It may be assumed that the reaction
conditions influence the grafting frequency so that
it is only at the optimum Oc the parameter range that
it is possible to obtain maximum grafting frequency
which guarantees the stability in storage and the process-
ibility of the product. If the limits of this range
of parameters are exceeded, increased viscosity and
coarsening of the particles in the polymer polyol to
the point of agglomeration and sedimentation are the
inevitable consequences. ~he use of polyethers having
a short chain length, equivalent weight less than lOOO,
also leads to highly viscous, coarse suspensions.
There is no technical teaching in the existing
literature to show how these limitations, to which the
process for producing polymer polyols is subject, can be
overcome and how the properties of the end product can
2Q be improved, even in the case of mixtures which are
critical in regard to viscosity and particle size.
It would be desirable for e~ample to obtain
a higher solids content, irrespective of the molecular
weight of the starting polyether, in order to increase
further the property-improving effect of the polymer
polyol and to make it possible for the processor to
blend the product with other polyols adapting the
requirements to the properties of his polyurethane foams.
At the same time, however, the processibility of the
product should not be adversely affected. In other
words neither viscosity nor particle size should be
increased too areatly~
It has already beer. proposed to use standard
molecular weight regulators and telogens in the in situ
polymerization reaction in order to reduce the viscosity
LeA 1~,~28
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of polymer polyQls in cr.itical mixtures. However, this
procedure has not yet been successful because these
substances, for example the mercaptans normally used for
polymerization purposes, compete with the polyether
polyol as transfer agents with a high transfer constant
and in fact reduce the grafting yield.
Although the quality of the end product can
be improved to a certain extent by increasing the
concentration of initiator, there are limits to this
process. ~ncreased additions of peroxide involve the
danger of an oxidative attack on the polyether. This
promotes degradation and cross-linking reactions. At
the same time, secondary products formed can give rise
to core discoloration in the production of foams. A
toxic secondary product is formed from azoisobutyro-
nitrile (AIBN), which has been successfully used in
practice, so that in this case, too, the concentration
of initiator should be kept as low as possible.
New developments in the processing technology
of flexible polyurethane foams, particularly in the
upholstery and automobile fields, have created a demand
for flame laminatability and high frequency ("HF")
weldability of flexible polyether-based foams with other
materials, particularly textiles. However, commercially
available fiexible polyether urethane foams cannot be
subjected to high-frequency welding. There has been no
shortage of attempts to make them suitable for HF-welding
by the incorporation of suitable additives, primarily
substances having a high dielectric constant.
In particular, it would seem to be desirable
to provide the foam manufacturer with ready-formulated
starting materials from wnich HF-weldable foams can be
produced without any need for further additives~
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~5~885
Numerous free radical polymerizable, ethylenically
unsaturated co~pounds are described in the existing patent
literature as being suitable for the production of polymer
polyols. However, apart from the polyether polyols modified
by the polymerization of acrylonitrile or styrene/
acrylonitrile mi~tures, no other products have as yet
acquired any commercial significance. This is in spite
of the fact that small quantities of other monomers
may be combined with styrene and acrylonitrile without
the properties of the end product being significantly
altered.
In the known Patents, for example German Patent
1,222,669, reference is made to the use of a,~-unsaturated
monocarboxylic and polycarboxylic acids, although products
1~ on this basis distinguished by particular properties or ~y
improved processibility have not yet been described.
In particular, it is not apparent from the existing
literature that the presence of ~,~-unsaturated carboxylic
acids during the polymerization reaction would make it
possible for the stability problems referred to above
to be solved and the process limits to be extended.
The object of the present invention is to
provide a process for the production of polymer polyols
which may be applied more universally than those
previously known. The process of the invention
shows improvements in the size of the monomer content,
the monomer ratio and the choice of the starting
polyether and, in addition, gives products which may
be converted into foams and show outstanding mechanical
properties, and may also be HF-welded. The larger number
of polyethers which may be converted into poly.mer polyols
by the new process also ma~es it possible for new fields
of application to be opened up for the class of products
in ~uestion.
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^~15~885
~E~CRIPTION OE THE INVENTION
The present invention relates to a process
for the production of modified polyether polyols by the
radical polymerization of
S I) 1 to 60 parts by weight of a mixture of
(A) 20 to 99~9% by weight of acrylonitrile,
(B) 0 to 80~ by weight of styrene
(C) 0.1 to 10% by weight of an ~
unsaturated monocarboxylic or polycar-
boxylic acid, and
(D) 0 to 20 % by weight of one or more other
copolymerizable compounds, the indivi-
dual quantities adding up to 100% by
weight, in
II) 99 to 40 parts by weight of a polyether
polyol, the sum of I~ and II) adding up to 100 parts by
weight~ in the presence of a free radical-forming poly-
merization initiator, which is characterized in that
the ~ unsaturated monocarboxylic or polycarboxylic acid
(C) is used in the form of a salt with a primary,
secondary or tertiary monoamine or polyamine.
The a,~-unsaturated carboxylic acids and
polycarboxylic acids used for the polymerization reaction
according to the invention may be any known ~,~-unsaturated
carboxylic acids and polycarboxylic acids. Examples
include acrylic and methacrylic acid, crotonic acid,
maleic acid, fumaric acid~ itaconic acid or citraconic
acid, to mention only the commercially most important.
It is also possible to use the oli~omers obtainable by
Michael's addition of acrylic acid on its own which
correspond to the formula
O O
CH2= CH-C--O ( CH2-CH2-C-O )n H
in which n is an integer of from 1 to 5, preferably 1.
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Other suitable carboxylic acids are the semiesters
and semiamides of ~,~-unsaturated dicarboxylic acids,
for example monoethyl maleate or fumaric acid-n-butyl
amide. The semiesters of saturated dicarboxylic acids
with unsaturated alcohols, for example monoallyl
succinate or phthalate are also suitable.
The choice of the amine used for salt formation
is not critical and, in individual cases, might be
limited solely by the poor solubility of the carboxylic
acid salt formed in the monomer mixture. Thus, it is
possible to use virtually any aliphatic and aromatic
monoamine,a polyamine and also heterocyclic bases.
Examples of suitable amines are aliphatic
open-chain or cyclic amines and hydroxy amines
lS containing from 1 to 18 carbon atoms per alkyl radical,
for example methyl amine, dimethyl amine, trimethyl
amine, diethyl amine, triethyl amine, isopropyl amine,
isobutyl amine, _-butyl amine, di-n-butyl amine, and
tri-n-butyl amine. Ethanolamine, diethanolamine, tri-
ethanolamine, N-methyl diethanolamine, N,N-dimethyl
ethanolamine, diisopropanolamine, pyrrolidine, piperidine,
piperazine, N-2-hydroxy ethyl piperazine, ~2,2,2]-diaza-
bicyclo-octane, morpholine, N-methyl morpholine, ethylene
diamine and N,N-dimethyl aminopropyl amine are further
suitable examples.
Arcmatic amines, such an aniline, N-methyl
aniline, N,N-dimethyl aniline, N,N-diethyl aniline,
N,N-diethyl-p-toluidine, and phenylene diamines, are also
suitable.
Heterocyclic nitrogen bases, such as for
examp~ pyridine, picolines, quinoline, pyrrole,
imidazole, oxazoles, thiazoles, etc., and thPir substituted
derivatives may be used.
LeA 1~,528
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The amines which are preferred in the instant
invention are the tertiary amines. This is because they
interfere least with the urethane-forming reaction. On the other
hand it ha~ been ~ound that polymer polyols produced with di-n-
butyl amine may be processed without difficulLy andthat the use of hydroxy amines, such as triethanolamine
or methyl diethanolamine, does not adversely affect
the processibility of the resulting products either.
However, to avoid an excessive content of foreign
substances in the product, it is preferred to use mono-
amines and polyamines having a molecular weight or (in
the case of polyamine) equivalent weight of from 30 to 150
and preferably from 56 to lG0.
The monomers suitable for the in situ graft
polymerization reaction according to the invention are,
essentially, acrylonitrile and its mixtures with
styrene, the acrylonitrile content of the total monomer
mixture amounting to between 20 and 99.9~ by weight,
preferably to between 25 and 80% by weight and the
styrene content amounting to between 0 and 80% by
weight and preferably to between 20 and 75% by weight~
In addition, it is possible to use small quantities of
other copolymerizable comonomers, for example esters
of unsaturated monocarboxylic and dicarboxylic acids.
~xamples of these are acrylic acid, methacrylic acid, maleic
acid, fumaric acid or itaconic acid, with lower alcohols
containing from 1 to 8 carbon atoms, monoesters or
diesters of the above-mentioned carboxylic acids with
glycols, polyglycols or higher alcohols. Also suitable
are vinyl acetate, vinyl c~loride, vinylidene chloride,
methacrylonitrile~ acrylamide, methacrylamide, esters
of the above-mentioned unsaturated carboxylic acids
wi~h amino alcohol~, for example 2-N,N-dimethyl amino-
ethyl methacrylate, as well a~ esters of vinyl phosphonic
acid~ for example vinyl phosphonic acid dimethyl ester.
LeA lg,528
:~5~88~;
Polyether polyols which may be used as starting
materials in the instant invention are the addition
products known per se of cyclic ethers, such as ethylene
oxide, propylene oxide, epichlorohydrin,styrene oxide, 1,2-
butylene oxide and/or tetrahydrofuran, with startercompounds containing at least two Zerewitinoff-active
hydrogen atoms in the molecule, as described for
example in the book "Polyurethanes, Chemistry and Tech-
nology", Part I, pages 32 et seq, by J. H. Saunders
and K. C. Frisch. Suitable starter compounds are, for
example, polyhydroxyl compounds, such as alkylene glycols,
glycerol, trimethylol propane, pentaerythritol, sorbitol,
glucose, glucosides, sucrose and the polyhydroxyl compounds
obtainable by the condensation of formaldehyde
(formose and formitol), also water, ammonia, amino
alcohols, such as ethanolamine, diethanolamine or tri-
ethanolamine, and finally primary and/or secondary amines
or polyamines, such as ethylene diamine or aniline.
The polyether polyols used as starting materials for
the production of the polymer polyols preferably have
e~ui~alent weights of from lnO to 3000 and a hydroxyl
functionality of from 2 to 8. The polyether chains are
normally made up of propylene oxide and ethylene oxide
units. The ethylene oxide units may be arranged statis--
tically along the chain or in coherent blocks withinand/or at the end of the chain~ In the latter case,
particularly reactive polyether polyols having a high
primary hydroxyl-group content are formed, representing
a particularly suita~le starting material for the
30 production of the highly elastic cold-hardening flexible
foams~
The free radical polymerization reaction ~ay
be initiated by th~ usual radical-forming initiators. In
LeA 19,528
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this _onnection, it is desirable that their decomposition
rate should be fairly hi~h~ ~e., ~hat +hP half~
life period of thermal decomposition be short
enough under the polymerization conditions to ensure
that an adequate supply of radicals is always available
in the reaction medium. Initiators such as these are,
for example, organic peroxides, such as benzoyl peroxide
or lauroyl peroxide, and in particular percarboxylic
acid esters, such as tert.-butyl peroctoate and tert.-
butyl perpivalate, as well as aliphatic azo compounds.Azoisobutyronitrile has the greatest commercial
significance and is a particularly suitable initiator
for the production of polymer polyols. The initiator
is preferably used in a quantity of from 0.3 to 2~ by
weight, based on the monomer total. The half life
period of thermal decomposition at the polyrnerization
temperature should preferably be less than 5 minutes.
The instant process may be carried out either
continuously or in batches. For example, a mixture
containing the monomer or monomers, the initiator, the
a,~-unsaturated carboxylic acid salt and, optionally, part
of the polyether used, may be introduced into the polyether
preheated to the polymerization temperature in a stirrer-
equipped reactor. An alternative example is a mixture
of all the reactants being continuously pumped into a
reactor and the product commensurately removed through
an overflow. Polymerization may be carried out in the
presence or absence of additional solvents. In large-
scale operation or in production, it is advisable, because
of t~e possibility of premature initiaiion of polymeriza-
tion in the monomer mixture to be added, to only
introduce the initiator dissolved in a suitable organic
solvent inio the monomer stream just before it enters
the reaction zone, optionally via a mixing unit.
LeA 19,52~
,.
885
Alternatively, this solution is introduced separately
into the reactor.
The temperature at which polymerization is
carried out should be at least 100C and preferably be
in the range of 120 to 140C. The reaction may be
carried out in a system sealed against the external
pressure under the pressure which is spontaneously
adjusted at the temperature selected or in an open
system under ambient pressure. It is necessary to
displace the air p~esent from the entire apparatus by
purging with an inert gas, such as nitrogen or argon,
and to maintain an inert gas atmosphere in the system
throughout the entire process, The product is freed
from volatile fractions, particularly the residual
monomers, in known manner by vacuum distillation,
optionally in a thin-layer or fallin~-film evaporator.
The order in which the individual components
are added during preparation of the monomer mixture is
not critical, providing the suitable monomer combination
has been determined and the solubility of the selected
amine salt of the ~ unsaturated carboxylic acid
confirmed in preliminary tests. It is more favorable
to first mix the monomers, inthe selected ratio and
quantity, together with the a,~-unsaturated carboxylic
acid used, with the starting polyether and then to add
the amine, optionally dissolved in an inert organic
solvent. The polymerization initiator is best either
dissolved in the monomers o~alternati~ely,it is added
to the reaction mixture, for example in solution in an
inert organic solvent.
The polymer polyols produced by the instant
process are suitable for the production of polyurethane
plastics O r al kinds, above all flexible and semirigid
polyurethane foams, by known processes. They are free
from coarse, filterable and sedimenting fractions and
LeA lq,528
1.15~ 5
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have a considerably lower viscosity than the corres-
ponding products produced by conventional processes.
It is also possible by the instant process
to produce readily processible, finely divided
5 dispersions of a type which previously could not be
obtained free from sediment and agglomerate by known
processes or which could only be obtained with such
a high viscosity that they could not be processed in the
usual mixing and metering units normally used in poly-
urethane technology. Thus, it is possible to use newstarting polyethers or more concentrated products,
opening up new fields of application for polymer
polyols. One advantage of polymer polyols having higher
solids content is that the mechanical properties of
polyurethane foams produced therefrom, particularly
compression hardness and indentation hardness, can be
improved for the same unit weight. The scope available
to the processor for blending with other polyethers,
cross-lin~ers, plasticizers and other additives is
increased without the solids content falling below a
level at which no property-improving effects are
observed. In addition, the production of polymer polyols
having a high solids content is more economical because
the production costs involved are the same as thDse of
known standard products. This allows for making inexpen-
sive and low-viscosity formulations upon re-dilution
with pure polyether polyol~
It has surprisingly been found that the
polymer polyols produced ~y the instant process may
readily be high-frer~uency welded with other substrates,
for example textiles, without the need for the addition
of other substances having a high dielectric constant.
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~15~885
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This represents a considerable advance in the processing
of flexible polyether urethane foams.
The processes for producing polyurethane
plastics using polyme_ polyols and the technical
improvements obtainable with them are known per se.
Primary importance is attributed to the flexible, elastic
and highly elastic foams and also to the semi risid
foams to which the polymer polyols impart improved
hardness and bearing strength coupled with a favorable
hardness/unit weight relation. Other foam properties,
for example the open-cell character and freedom from
shrinkage of flexible foams, are also favorably
affected. Freedom from agglomerates and as low a
viscosity as possible are essential requirements
for the machine processing of polymer polyols. Piston
pump units impose a viscosity range upper limit of around
1500 to 2000 mPas.
Foaming machines equipped with different
types of delivery units, for example gear pumps, are
also suitable for use with the instant invention.
The instant invention also relates to a process
for the production of optionally cellular polyurethane
plastics by reacting
A) polyisocyanates with
B) polyether polyols modified by ~raft
polymerization and, optionally,
C) other relatively high molecular weight
and/or low molecular weight compounds containing isocyan-
ate reactive hydrogen atoms, optionally in the presence
of
D) blowing agents, catalysts and other additives
known per se,
which is c~aracterized in that the polymer polyols
LeA 1'~,528
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.
of the instant invention are used as component B).
The following materials are used for carrying
out the process o the instant invention:
1. As starting components, aliphatic,
cycloaliphatic, araliphatic, aromatic and heterocyclic
polyisocyanates of the type described for example by
W. Siefken in Justus Liebigs Annalen der Chemie, 562,
pages 75 to 136, for example those corresponding to the
formula
Q(NCO)n
in which:
n = 2 - 4, preferably 2,
and
Q represents an aliphatic hydrocarbon radical
containing from 2 to 36 carbon atoms and
preferably from 6 to 10 carbon atoms;
a cycloaliphatic hydrocarbon radical
containing from 4 to 15 and preferably from
5 to 10 carbon atoms, an aromatic hydrocarbon
radical containing from 6 to 15 carbon atoms
and preferably from 6 to 13 carbon atoms;
or
an araliphatic hydrocarbon radical containing
from 8 to 15 carbon atoms and preferably from
8 to 13 carbon atoms.
Suitable examples are ethylene diisocyanate; 1,4-tetra-
methylene diisocyanate; 1,6~hexamethylene diisocyanate;
1,12-dodecane diisocyanate; cyclobutane-1,3-diisocyanate;
cyclohexane-1,3- and -1,4-diisocyanate and mixtures
3Q of these isomers. Additional suitable compounds are
l-isocyanato-3,3,5-trLmethyl-5-isocyanatomethyl
cyclohexane (German Auslegeschrift 1,202,785, U. S.
Patent 3,401,190); 2,4- and 2,6-hexahydrotolylene
diisocyanate and mixtures of these isomers; hexahydro-
LeA 19,528
115~885
1,3- and/or -1,4-phenylene diisocyanate; perhydro-2,4'-
and/or -4,4'-diphenyl methane diisocyanate; 1,3- and
1,4-phenylene diisocyanate; 2,4- and 2,6-tolylene
diisocyanate and mixtures of these isomers; diphenyl
methane-2,4'- and/or -4,4'-diisocyanate and naphthylene-
1,5-diisocyanate.
According to the instant invention, it is also
possible for example to use triphenyl methane-4,4',4"-
triisocyanate, polyphenyl polymethylene polyisocyanates
10 of the type obtained by condensing aniline with
formaldehyde, followed by phosgenation, and described
for example in British Patents 874,430 and 848,671;
m- and p-isocyanatophenyl sulphonyl isocyanates according
to U.S. Patent 3,454,606. Additional examples are
15 perchlorinated aryl polyisocyanates of the type described
for example in German Auslegeschrift 1,157,601 (U.S.
Patent 3,277,138~; polyisocyanates containing
carbodiimide groups of the type described in German
Patent 1,092,007 (U.S. Patent 3,152,162) and in German
20 Offenlegungsschriften 2,504,400; 2,537,685, and
2,552,350; norbornane diisocyanates according to U.S.
Patent 3,492,330; polyisocyanates containing allophanate
groups of the type described for example in British
Patent 994,890 and Belgian Patent 761,626. Still more
25 examples of suitable compounds are for example, poly-
isocyanates containing isocyanurate groups of the type
described for example in U.S. Patent 3,001,973; German
Patents 1,022,789; 1,222,067 and 1,027,394 and German
Offenlegungsschriften 1,929,034 and 2,004,048 as well
30 as polyisocyanates containing urethane groups of the
type described for example in Belgian Patent 752,261 or
in U.S. Patents 3,394,164 and 3,644,457. Polyisocyanates
containing acylated urea groups according to German
Patent 1,230,778; polyisocyanates containing biuret groups
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of the type described for example in U. S. Patents
3,1~4,605; 3,201,372 and British Patent
889,050; polyisocyanates produced by telomerization
reactions of the type described for example in U. S.
Patent 3,654,106 and polyisocyanates containing ester
groups of the type described for example in British
Patents 965,474 and 1,072,956; U. S. Patent 3,567,763
and German Patent 1,231,688 are still more examples of
suitable compounds. Reaction products of the above
mentioned isocyanates with acetals according to German
Patent 1,072,385 and polyisocyanates containing polymeric
fatty acid esters according to U. S. Patent 3,455,883
are also suitable compounds for use as starting materials
in the instant invention.
It is also possible to use the isocyanate-group-
containing distillation residues obtained in the commercial
production of isocyanates, optionally in solution in
one or more of the above mentioned polyisocyanates. It
is also possible to use any mixtures of the above
mentioned polyisocyanates.
In general, it is particularly preferred to
use the commercially readily available polyisocyanates,
for example 2,4- and 2,6-tolylene diisocyanate, and/or
any mixtures of these isomers ("TDI"). Polyphenyl
polymethylene polyisocyanates of the type obtained by
condensing aniline with formaldehyde, followed by
phosgenation ("crude MDI") and polyisocyanates containing
carbodiimide groups, urethane groups or biuret groups
("modified polyisocyanates"), particularly modified
polyisocyanates of the type derived from 2,4- and/or 2,6-
tolylene diisocyana~e or from 4,4'- and/or 2,4'-
diphenyl methane diisocyanate are also particularly
prererre~.
2. As further optional starting components:
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~115~i885
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compounds con~aining at least two isocyanate-reactive
hydrogen atoms an~ having a molecular weight of from 400
to 10,000. In addition to compounds containing amino
groups, thiol groups or carboxyl groups, preferable
compounds contain hydroxyl groups, particularly compounds
containing from 2 to 8 hydroxyl groups, above all those
which have molecular weights of from 400 to 7000,
preferably from 1000 to 5000. Examples of these compounds
are polyesters, polyethers, polythioethers, polyacetals,
polycarbonates and polyester amides containing at least
2, generally from 2 to 8, but preferably from 2 to
4 hydroxyl groups, of the type ~nown per se for the
production of homogeneous and cellular polyurethanes.
Representatives of the above-mentioned
compounds which may be used with the instant invention
are described for example in High Polymers, Vol. XVI,
"Polyurethanes, Chemistry and Technology", by Saunders-
Fr sch, Interscience Publishers~ New York/London, Vol. I,
1962, pages 32-42 and 44-54 and Vol. II, 1964, pages
5-6 and 198-199, and in Kunststoff-Handbuch, Vol. VII,
Vieweg-~ochtlen, Carl-Hanser-Verlag, Munich, 1966,
for example on pages 45 to 71. It is of course also
possible to use mixtures of the above-mentioned compounds
containing at least two isocyanate-reactive hydrogen
atoms and having a molecular weight of from 400 to 10,000,
for example mixtures of polyethers and polyesters~
In some cases, it is particularly advantageous
to combine low-melting and high~melting polyhydroxyl
compounds with one another as described in German
Offenlegungsschrift 2,7Q6,297.
3. Compounds containing at least two isocyanate-
reactive hydrogen atoms and ~aving a molecular weight
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-18-
of rrom 32 to 4Q0 may also be used as starting components.
These compounds also contain hydroxyl groups and/or
amino groups and/or thiol groups and/or carboxyl groups,
preferably compounds containing hydroxyl groups and/or
amino groups which serve as chain extenders or cross-
linkers~ These compounds generally contain from 2 to 8
and preferably from 2 to 4 isocyanate-reactive hydrogen
atoms.
Here also, it is possible to use mixtures
of different compounds containing at least two isocyanate-
reactive hydrogen atoms and having a molecular weight
of from 32 to 400.
Examples of compounds such as these are ethylene
glycol, 1,2- and 1,3-propylene glycol; 1,4- and 2,3-
butylene glycol; 1~5-pentane diol; 1 r 6-hexane diol; 1,8-
octane diol; neopentyl glycol; 1,4-bis-hydroxymethyl
cyclohexane; 2-methyl-1,3-propane diol; and dibromobutene
diol (U. S. Patent 3,723,392). Additional examples
of these compounds are glycerol; trimethylol propane;
1,2,6-hexane triol; trimethylol ethane; pentaerythritol;
quinitol; mannitol and sorbitol; castor oil; diethylene
glycol; triethylene glycol; tetraethylene glycol; higher
polyethylene glycols having a molecular weight of up
to 400, dipropylene glycol; higher polypropylene glycols
having a molecular weight of up to 400; dibutylene
glycol; higher polybutylene ~lycols having a molecular
weight of up to 400, 4~4'~dihydroxy diphenyl propane;
dihydroxy methyl hydroquinone; ethanolamine; diethanolamine;
N-methyl diethanolamine, triethanolamine and 3-aminopropanol.
In the instant invention, suitable low molecular
weight polyols are also the mixtures of hydroxyl
aldehydes and hydroxy ketones ~"formose"), or the poly;
hydric alcohols obtained therefrom by reduction ("formitolN)
LeA 19,528
~15~85
--19--
which are formed in the autocondensation of formaldehyde
hydrate in the presence of metal compounds as catalysts
and compounds capable of enediol formation as cocatalysts
(German Offenlegungsschriften 2,639,084; 2,714,084;
2,714,104; 2,721,186; 2,738,154 and 3,738,512).
In order to obtain plastics with improved flame resistance,
these formoses are advantageously used in combination
with aminoplast formers and/or phosphites IGerman
Offenlegungsschriften 2,738,513 and 2,738,532). Solutions
Of polyisocyanate polyaddition products, particularly
solutions of polyurethane ureas containing ionic groups
and/or solutions of polyhydrazodicarbonamides, in low
molecular weight polyhydric alcohols may also be used
as the polyol component in the present invention (German
Offenlegungsschrift 2,638,759).
Aliphatic diamines suitable for use in the
instant invention are, for example~ ethylene diamine,
1,4-tetramethylene diamine, l~ll-undecamethylene diamine,
1,12-dodecamethylene diamine and mixtures thereof.
Additional examples are l-amino-3,3,5-trimethyl-5-amino-
methyl cyclohexane (nisophorone diamine"), 2,4- and 2,6-
hexahydrotolylene diamine and mixtures thereof~ Perhydro-
2,4'- and -4,4'-diaminodiphenyl methane; ~-xylylene
diamine; bis-(3-aminopropyl)-methyl-amine; diaminoperhydro
anthracenes (German Offenlegungsschrift 2,638,731) and
cycloaliphatic triamines according to German Offenlegungs-
schrift 2,614,244 are still further examples of suitable
aliphatic diamines~ It is also possible in the present
inYention to use hydrazine and substituted hydrazines,
for example methyl hydrazine, N,N'-dimethyl hydrazine and
their homologs. Acid dihydrazides~ for example
carbodihydrazide; oxalic acid dihydrazide; the dihydra-
zides of malonic acid; succinic acid; slutaric acidt
adipic acid; ~-methyl adipic acid; sebacic acid; hydracrylic
LeA 1~,528
~1S~885
-20-
acid and terephtAalic acid; semicarbazido propion-c acid
hydrazide (German Offenlegungsschrift 1,770,591) are
also suita~le. Semicarbazido alkylene carbazinic esters
such as, for example, 2-semicarbazido ethyl carbazinic
ester (German Offenlegungsschrift 1,918,504) or even
amino-semicarbazide compounds such as, for example, ~-
aminoethyl semicarbazido carbonate (German Offenlegungs-
schrift 1,902,931) may also be used in the present inven-
tion. To control their reactivity, the amino groups
may be completely or partly blocked by aldimine or
ketimine groups (U. S~ Patent 3,734,894; German
Offenlegungsschri'ft 2,637,115).
Examples of aromatic diamines are bis-anthranilic
acid esters according to German Offenlegungsschriften
2,040,644 and 2,160,590; 3,5- and 2,4-diaminobenzoic
acid esters according to German Offenlegungsschrift
2,025,900; the diamines containing ester groups
described in German Offenlegungsschriften 1,803,635
(U. S. Patents 3,681,290 and 3~736,350); 2,040,650
and 2,160,589. The diamines containing ether
groups according to German Offenlegungsschriften 1,770,525
and 1,809,172 (U. S. Patents 3,654,364 and 3,736,295);
2-halogen-1,3-phenylene diamines which may be substituted
in the 5-position (.German Offenlegungsschriften
2,0al,772; 2,025,896, and 2,065,869); 3,3'-dichloro-4,4'-
diaminodiphenyl methane; tolylene diamine; 4,4'-diamino-
diphenyl methane; 4,4'-diaminodiphenyl disulfides
(.German Offenlegungsschrift 2,404,976) are further
examples of suita~le aromatic diamines. Diaminodiphenyl
dithioethers (German Offenlegungsschrift 2~50.9,4041;
aromatic diamines su~stituted by alkyl thio groups
(.German O~fenlegungsschrift 2~638,760~; diaminobenzene
phosphonic acid esters ~German Offenlegungsschrift
2,459,491); aromatic diamines containing sulfonate or
car~oxylate groups (German Offenlegungsschrift 2,720,1661
~eA 19,528
~5~885
and the high-melting diamines described in German
Offenlegungsschrift 2,635,400 are further examples.
Examples of aliphatic-aromatic diamines are the amino-
alkyl thioanilines according to German Offenlegungsschrift
2,734,574.
In the instant invention, other suitable chain
extenders are such compounds as l-mercapto-3-amino-
propane, amino acids which may be substituted for
example glycine, alanine, valine, serine and lysine
and dicarboxylic acids which may be substituted for
example succinic acid, adipic acid, phthalic acid, 4-
hydroxy phthalic acid and 4-aminophthalic acid.
In addition, isocyanate-monofunctional compounds
may be used as so-called chain terminators in proportions
Of from 0.01 to 10% by weight, based on polyurethane
solids. Monofunctional compounds such as these are,
for example, monoamines, such as butyl and dibutylamine,
octylamine, stearylamine, N-methyl stearylamine,
pyrrolidine, piperidine and cyclohexylamine and monoalco-
hols such as butanol, 2-ethyl hexanol, octanol, dodecanol,
the various amyl alcohols~ cyclohexanol, ethylene glycol
monoethyl ether.
4. As optional additives and auxiliaries:
Water and/or readily volatile inorganic or
organic substances as blowing agents. Organic blowing
agents include for example, acetone, ethylacetate, halogen-
substituted alkanes, such as methylene chloride, ch~oro-
form, ethylidene chloride, vinylidene chloride, monofluoro-
trichloromethane, chlorodifluoromethane~ dichloro-
difluoromethane, also butane, hexane, heptane ordiethyl ether. Inorganic blowing agents include for
example, air, CO2 or N2O. A blowing effect may also
be obtaine~ by adding compounds which decompose at temper-
atures above room temperature giving off gases, such as
~eA 19,528
S85
-~2-
nitrogen, for exa~.ple azo compounds such as azo-
dicarbonamide or azoisobutyronitrile. Other examples
of blowing agents and information on the use of blowing
agents can be found in Kunststoff-Handbuch, Vol. VII,
by Vieweg and Hochtlen, Carl-Hanser-Verlag, Munich,
1966, for example on pages 108 and 109, 453 to 455 and
507 to 510.
Catalysts known per se, for example tertiary
amines may also be used. Examples of such tertiary
amines are triethylamine, tributylamine, N-methyl
morpholine, N-ethyl morpholine, N,N,N'N'-tetramethyl
ethylene diamine, pentamethyl diethylene triamine and
higher homologs (German Offenlegungsschriften 2,624,527
and 2,624,528); 1,4-diazabicyclo-(2,2,2)-octane; and
N-methyl-N'-dimethylaminoethyl piperazine. Bis-
(dimethyl-aminoalkyl)-piperazines (German Offenlegungs-
schrift 2,636,787); N,N-dimethyl benzylaminej N,N-
dimethyl cyclohexylamine; N,N-diethyl benzylamine; bis-
(N,N~-diethyl-aminoethyl)-adipate; N,N,N'NI-tetramethyl-
1,3-butane diamine; N,N-dimethyl-~-phenyl ethylamine;
1,2-dimethyl imidazole; 2-methyl imidazole; monocyclic
and bicyclic amidines ~German Offenlegungsschrift 1,720,633)
arestill further examples of suitable compounds.
Bis-(dialkylamino)-alkyl ethers (U. S. Patent 3,330,782,
German Auslegeschrift 1,030,558 and German Offenlegungs-
schriften 1,~04,361 and 2,618,280) and tertiary amines
containing amide groups (preferably formamide groups)
according to German Offenlegungsschriften 2,523,633
and 2,732,292 are further examples of suitable compounds.
Other suitable catalysts are the Mannich bases known per
se of secondary amines, such as dimethylamine, and alde-
hydes, preferably formaldehyde, or ketones, such as
acetone, methylethyl ketone or cyclohexanone, and phenols,
such as phenol, nonyl phenol or bisphenol.
LeA 19,528
885
-~3_
Tertiary amines containing isocyanate-
reactive hydrogen atoms suitable for use as catalysts
are, for example, triethanolamine, triisopropanolamine,
N-methyl diethanolamine, N-ethyl diethanolamine, N,N-
dimethyl ethanolamine and their reaction productswith alkylene oxides, such as propylene oxide and/or
ethylene oxide. Also suitable as catalysts are
secondary-tertiary amines according to German
Offenlegungsschrift 2,732,292.
Other suitable catalysts are sila-amines
containing carbon-silicon bonds, of the type described
for example in German Patent 1,229,290 (corresponding
to U. S. Patent 3~620,984), for example 2,2,4-trimethyl-
2-silamorpholine and 1,3-diethylaminomethyl tetramethyl
disiloxane.
Other suitable catalystsare nitrogen-containing
bases, such as tetraalkyl ammonium hydroxides, also
alkali hydroxides such as sodium hydroxide, alkali
phenolates, such as sodium phenolate, or alkali alcoholates,
such as sodium methylate. Hexahydrotriazines may also
be used as catalysts as described in German Offenlegungs-
schrift 1,769,043.
~ he reaction between ~CO-groups and Zerewitinoff-
active hydrogen atoms is also greatly accelerated by
lactams and azalactams, an associate between the lactam
and the compound containing acid hydrogen initially being
formed. Associates such as these and their catalytic
effect are described in German Offenlegungsschriften
2,062,288; 2,062,289; 2,117,576 (U. S. Patent 3,758,444);
2,129,198; 2,330,175 and 2,330,211).
It i5 also possible to use organometallic
compounds, particularly organo tin compounds, as catalysts.
In addition to sulfur-containing compounds, such as di-_-
octyl tin mercapti~e as described in German Auslegeschrift
LeA 19,528
~15~`885
-24-
1,769,367 and U. S. Patent 3,645,927, preferred
organo tin compounds are tin (II) salts of carboxylic
acids, such as tin (II) acetate, tin (II) octoate, tin
(II) ethyl hexoate and tin(II) laurate, and tin (IV)
compounds, for example dibutyl tin oxide, dibutyl
tin dichloride, dibutyl tin diacetate, dibutyl tin
dilaurate, dibutyl tin maleate or dioctyl tin
diacetate.
All the above mentioned catalysts may of course
be used in the form of mixtures~ In this respect,
combinations of organometallic compounds and amidines,
aminopyridines or hydrazino pyridines as described in
German Offenlegungsschriften 2,343,185; 2,601,082 and
2,603,834 are of particular interest.
Further examples of catalysts suitable for
use in the instant invention and information on the way
in which they work can be found in Kunststoff-Handbuch
by Vieweg and Hochtlen, Vol. VII, Carl-Hanser~Verlag,
Munich 1966, for example on pages 96 to 102.
The catalysts are generally used in a quantity
of from about 0.001 to 10~ by weight, based on the
total quantity of compounds containing at least two
isocyanate-reactive hydrogen atoms.
Surface-active additives, such as emulsif-ers
and foam stabilizers may also be used with the instant
invention. Suitable emulsifiers are for example the sodium
salts of castor oil sulfonates or salts of fatty acids
with amines, such as diethylamine oleate or diethanolamine
stearate. Alkali or ammonium salts of sulfonic acids,
3~ such as for example dodecyl benzene sulfonic acid or
dinaphthyl methane disulfonic acid, or of fatty acids,
such as ricinoleic acid, or of polymeric fatty acids
may also be used as surface-ac-ive additives~
LeA 19,528
:~S~885
-25-
Sultable roam stabilizers are, above all,
polyether siloxanes, particularly water soluble types.
The structure of these comDounds is generally such that
a copolymer of ethylene oxide and propylene oxide is
attached to a polydimethyl siloxane residue. Foam
stabilizers such as these are described for example
in U. S. Patents 2,834,748; 2,917,480 and 3,629,308.
In many cases, polysiloxane-polyoxyalkylene copolymers
branched through allophanate groups according to German
Offenlegungsschrift 2,558,523 are of particular interest.
Reaction retarders, for example acid-reacting
substances such as hydrochloric acid or organic acid
halides are suitable for use with the instant invention.
Cell regulators known per se, such as paraffins or fatty
alcohols or dimethyl polysiloxanes and also pigments
or dyes and flameproofing agents known per se, for
example tris-chloroethyl phosphate, tricresyl phosphate
or ammonium phosphate and polyphosphate are also suitable.
Stabilizers against the effects of aging and weatner,
plasticizers and fungistatic and bacteriostatic substances
as well as fillers such as barium sulfate, kiesel~uhr,
carbon black or whiting are examples of other additives
which may be used with the instant invention.
Purther examples of surface-active additives
and foam stabilizers, cell regulators, reaction retarders,
stabilizers, flameproofins agents, plasticizers, dyes,
fillers, fungistatic and bacteriostatic substances which
may be used in the instant invention and information on
the way in which these additives are used and on their
respective modes of action can be found in Kunststoff-
~andbuch by Vieweg and Hochtlen, Vol. VII, Carl-Hanser-
Verlag, Munich 1~66, for example on pages 1~3 to 113.
The proc~ss of the instant invention is
carried out as descrihed below
LeA 19,5~8
i85
mhe reaction components are reacted by the
one-shot process known per se, by the prepolymer
process or by the semi-prepolymer process, in many
cases using machines, for example of the type
described in U. S~ Patent 2,764,565. Particulars of
processing machines which may also be used can be
found in Kunststoff-Handbuch by Vieweg and Hochtlen,
Vol. VII, Carl-Hanser-Verlag, Munich, 1966, for example
on pages 121 to 205.
In the production of foams, it is also
possible to carry out foaming in closed molds. The
reaction mixture is introduced into a mold. Suitable
mold materials are metals, for example aluminum, or
plastics, for example epoxide resin. The foamable
reaction mixture foams in the mold and forms the molding.
In-mold foaming may be carried out in such a way that
the molding has a cellular structure at its surface,
although it may also be carried out in such a way
that the molding has a compact skin and a cellular core.
It is possible to introduce foamable reaction mixture
into the mold in such a quantity that the foam formed
just fills the mold. It is also possible to introduce
into the mold more foamable reaction mixture th~n is
required for filling the interior of the mold with
foam. This particular technique is known as overcharging
and is known for example from U, S. Patents 3,178,490
and 3,182,104.
In many cases~ "external release agents"
known per se, such as silicone oils, are used for in-
mold foaming. It is also possible to use so-called
"internal release agents", which may be used in admixture
with external release agents, of the type known for
exam~le from German Offenlegungsschriften 2,121,670 and
2,307,589.
LeA 19,528
.
~15~ 35
-27-
It is also possible to produce cold-hzrdening
foams (cf. British Patent 1,162,517 and German
Offenlegungsschrift 2,153,086).
It is of course also possible to produce
foams by block foaming or by the laminator process
known per se.
The instant process is illustrated, but in no
way restricted, by the following Examples in which
the quantities quoted represent parts by weight or
percentages by weight, unless otherwise stated.
The following abbreviations and designations
are used in the following Examples:
AIBN: Azoisobutyronitrile (radical polymerization
initiator)
15 AS: Acrylic acid
DAS: Dimeric acrylic acid CH2=CH-CO-O ~H2~OOH
MAS: Methacrylic acid
MSA: Maleic acid anhydride
ITS: Itaconic acid
20 TEA: Triethyl amine
DBA: Di-n-butyl amine
TELA: Triethanolamine
MDELA; Methyl diethanolamine
DMA: N,N-dimethyl aniline5 Polyol A: A trimethylol-propane-started polypropylene
oxide polyether containing terminal poly-
oxyethylene blocks and ha~ing an ethylene
oxide content of 17% and a molecular weight
of approximately 4800.0 Polyol B: A trimethylol-propane-started polypropylene
oxide having a molecular weight of approx-
imately 3000.
Polyol C: A glycerol-started polypropylene oxide
polyether containing terminal polyoxyethylene
LeA 19,528
~15(~88S
-28-
blocks (5%) and having a molecular weight
of approximately 3000.
Polyol D: A polypropylene glycol having a molecular
weight of approximately 2000.
Polyol E: A polypropylene glycol containing 5% of
terminal polyoxyethylene blocks and having
a molecular weight of approximately 2000.
Polyol F: A polypropylene glycol having a molecular
weight of approximately 1000.
Polyol G: A propoxylated trimethylol propane having
a molecular weight of approximately 300.
Polyol H: A trimethylol-propane-started polypropylene
oxide polyether containing 13% of terminally
incorporated polyoxyethylene blocks and
having a molecular weight of approximately
6000.
The viscosities were determined at room temperature
(22-23C) using a Haake-Viskotester* (VT 02; No. spindle).
In order to determine the non-filterable component, the
product was filtered through a metal sieve (mesh width
100 ~m), the sieve residue was washed with methanol,
dried and weighed out; the quantities observed are based
on the total solids.
EXAMPLES
EXAMPLE 1
100 g of polyol A were heated to 120C in
a reaction vessel equipped with a blade stirrer, reflux
condenser, thermometer, gas inlet pipe and dropping
funnel and heated by an oil bath. A mixture of 500 g
of polyol A, 140 g of styrene, 240 g of acrylonitrile,
20 g of DAS, 20.7 g of TELA and 4 g of AIBN (1~, based on
the total amount of monomer) was introduced through the
dropping funnel over a period of two hours. On completion
35 of the addition, the mixture was heated with stirring for
4 hours and, finally, the volatile fraction was distilled
* Trademark
LeA 19,528
5~`s885
-29-
off in vacuo, leaving a pale yellowish, finely divided
dispersion free from agglomerate particles and sediment
and havina a viscosity of 4100 mPas at 22C. The
hydroxyl number amounted to 31.9, the acid number to
2.1 and the quantity of distilla~e to 32 g. According
to a gas chromatogram, the distillate consisted of
acrylonitrile and styrene and contained traces of
TELA. The analytical data show a monomer conversion
of 92% and a solids content of the dispersion of 38%.
For comparison, the test was repeated using
DAS itself rather than its amine salt as comonomer. For
otherwise the same procedure, a highly viscous, gritty
paste was formed. It had a viscosity of 55,000 mPas
at 22C and was unsuitable for further processing into
polyurethane plastics~
EXANPLE 2
Under the same conditions as in Example 1,
a mixture of 3000g of polyol A, 1125 g of styrene ! 1800 g
of acrylonitrile, 75 g of AS, 134 g of DBA and 30 g of
AIBN was added dropwise over a period of 5 hours at
120C to 1500 g of polyol A, after which the reaction
mixture was stirred for 3 hours at 120C. Vacuum
distillation gave 249 g of distillate, the product was
a white, yellow-tinged homogeneously finely divided
dispersion having a viscosity of 4600 mPas/23C, a
hydroxyl number of 22.2, an acid number of 1.6 and a
solids content of 3~.1%
The test was repeated in a 100 liter stainless steel
autoclave using a batch increased by a factor of 10,
3000 g of toluene being added to the mixture introduced
in order to reduce its viscosity. The product had a
solids content of 39~2%, a viscosity of 4700 mPas,
a hydroxyl number of 19.3 and an acid number of 2 4.
The test could be carried out without difficulty on an
even larger scale.
LeA 19,528
~15~S
- 29 a -
A trial run was carried out in a 500 1 stainless steel steam
heated kettle,427 kg of a polymer polyol havinga n
OH number of 2008, an acid number of 104, and a viscosity
of 5200 m PaOs at 20 C are obtained, which was free
from sedimenting particles and passed through a 100 um
sieve without leaving a residue.
Le A 19,528
-30-
EXAMPLE 3
The procedure was as in Example 1. The following
mixture was added dropwise over a period of 2 hours at
120C to 100 g of polyol A:
Polyol A5Q0 g
Styrene15Q g
Acrylonitrile 240 g
M~S 12 g
TE~A 2Q.7 g
AIBN 4 g
Distillate32 g
Solids content 38.1
Monomer conversion 92 ~
Viscosity 4200 mPas/23C
OH number 33.9
Acid number 2.1
This batch was increased by a factor of 67.5 and
the test repeated in a 100 liter fine-steel autoclave
in the same way as in Example 2. The product was a
finely divided, stable dispersion having a solids content
of 39.5%, a hydroxyl number of 37.2, an acid number of
2.4 and a viscosity of 6000 mPas. The test was repeated
in a 500 1 stirred reactor yielding a dispersion with
an OH-number of 42.3, an acid number of 0.85, and a
viscosity of 7800 mPas/20C. It passed through a 100 ~m
sieve without leaving a residue.
EXAMPLE 4
300 g of polyol A were heated to 120C and
the following mixture added over a period of 2 hours:
Polyol A1800 g
Styrene360 g
Acrylonitrile 530 g
DAS 10 g
TELA 10 g
AIBN 9 g
A total of 55.5 g of volatile fractions was
distilled _ vacuo. This corresponds to a conversion of
LeA 19,528
`~
S~
-31-
94% of the monomers used and to a solids content of 28.7%.
A very finely divided dispersion having a viscosity of
3700 mPas/22C was formed.
EXAMPLE 5
This Example shows that the effect of the
reduction in viscosity occurs even with only partial salt
formation of the ~,~-unsaturated carboxylic acid. In
one test, the carboxylic acid used was not neutralized
at all; in another test, it was only 50~ neutralized
with the amine. The procedure was as in Example 1.
Test I II
Product
initially introduced: Polyol 100 g 100 g
A (heated under nitrogen to
120C)
~S;xture introduced:
Poly~l A 500 g 500 g
Styrene 156 g 156 g
Acrylonitrile240 g 140 g
AS g
TELA - 4~1 g
Toluene 200 g 200 g
A13N 4 g 4 g
Mbnomer conversion: 95.5 % 98.8 %
Solids content; 38.9 % 39.7 ~
Viscosity at 23C; 18,000 mæas 3900 mPas
Appearance I~ generally finely d:~ided
dispersion permeated by co~rse
agglomerate particles
II) finely divided, agglomerate-free
and sediment-free dispersion
EX~MPLES 6 to 19
The following tests were carried out in a two
LeA 19,528
S`85
-3~-
liter capacity alass apparatus of the type described
in Example 1. The quantities by weight are given in g.
The reaction temperature was 120C in every case.
Exam~le
No. 6 7 8 9 10 11 12 13
Product
init;~lly
mtroduced
(in ~m~)
Polyol A 200200 200 200 200 100 100 100
Toluene 25 25 25 25 25 25 25 25
Mixture
introduced:
Poly~l A 400400 400400 400 400 400 300
10 T~luene 50 50 5050 50 50 50 50
A~ryloni-
trile 240240 240200 200 375 300 360
Styrene 150150 155190 185 100 190 220
AS 10 - - - - - 10
MAS - - 5 - 15 - - 20
15 DAS _ _ _10 - 25
M~;A -- 10
IEA - - 6 - - - 14
DBA - - - - 23 - -30.7
TEIA - - - 10.3 -
20 MDEIA - 12.1 -
DMA 16.8
AI~N 4 4 4 4 4 5 5 6
LeA 19,528
--33--
O O~ InO~ ~ ~ ~ ~ ~ O
~` CO~ ~ oo ~ o
In ~~ ul ~
u~ I~ ~ r-- cr~ ~ o o
_I
I o
j~ r-- _I~ cn r~ ~ o
o I ~ I o
I~r ~1 ~~ 1~ ~ a~o
O ~ a~ u~I LO~
. . . - , $ ~
b ~ `J co ~ o o
a~
er ~D n o ~ ~ o
. , . . . . .~ o
~i r~ I` oo co ~D ~00t~l O
a~ O
In U'~ r o ~ o
. . . . . . . I o C) ;~
~D Il Ct> C~ ~ ~ OC~ ~1 0 _I
o~ Q
__ ~ .
.~
~ ~ ~ ~ oO
a
_l O s~ o ,1 a~ n~ u~
l ~ ~
I~ 19,528
`~15i`~35
- 34 -
Example N~.14 15 16 17 18 19
-- _
Product
~nitially
introduced
(in grams)
P~ly~l B 200200 200 200 200 200
T~luene 25 25 50 50 50 50
Mixture
introduced:
Polyol B 400400 400 400 300 200
T~luene 50 50 100 100 100 100
~crylonitrile 240 240 240 200 300 360
Styrene 150145 155 190 190 215
AS 10 - - 10 - 25
M~S - 15 - - 10
T~ 14 - 7.8
DB~ - 22.5 - - - 44.8
DM~ - - - 16.8
_ _ 17.7
AIBN 4 4 4 4 5 6
LeA 19,528
~s~s
-35-
Example No. 14 15 16 17 18 19
~r
oonversion (~)93.7 94.5 93.1 95.1 97.8 95.2
Acrylonitrile
bcun~l) 58.2 58.9 58.0 48.4 59.7 59.0
Styrene boundl)39.1 37.1 40.7 49.0 38.3 36.6
GC-analysis of
the distillate:
% Acrylonitrile22,0 17.4 24.3 16.1 8.2 22.9
% Styrene 3.4 4~8 3~7 3.6 2.9 6.0
Solids
oontent (%) 38.4 38.6 38.3 38.8 49.4 58.8
OH-numker 34.3 34~5 34.7 33.9 38.9 23.5
Nbn-filterable
ccmponent
(%, based on
solids); 100 ~m
mesh sieve- ~ O,1 - - - <O,1
Visoosity
(mPas) 3300 2900 2900 4300 4600 490Q
1)
%, based on the solids oontent
LeA 19,528
:~15~35
-36
EX~NPIES 20 bo 27
The following Examples were carried out under the same
conditions as EXamples 6-19.
Example Nb.20 21 22 23 24 25 26 27
Product
initially
~troduced
(in grams):
Polyol C 200200 200 100 100
PD1Y~1 E - - - - - 100100 100
P~1YD1 F - - - - - 100100 100
Tbluene 50 50 50 50 50 50 50 50
Mixture
intra~uced
(in grams):
PDlyol C 400400 400 400 300
PO1YD1 E - - - - - 300250 250
PD1Y~1 F - - - - - 300250 250
Acrylonitrile 240 240 240 300360160 240 240
Styrene 150145 155 190 215 30 50 50
AS 10 - - - 25 10 10 10
M~S - 15 - 10 - - - -
TEL~ - - - 17.7 - - -2a.7
DBA - 22~5 - - 44.8 - -
TE~ 14 - 7.8 - - 14 14
l~luene 100lQ0 lOQ lQ0 100100100 lQQ
AIBN 4 4 4 5 6 2 3 3
LeA 1~528
--37--
t~ I O ~ O O ~ er ~D g
. I`O 1` O~_i ~ er O
o~o~ ~ ~ ~ I~ _I
ou~ $
~D~ U~ ~~7 ~ O~ CO
C~
~nlo~ u~ ~ o ~ o~ o
.. . . , . . o
. .. . , . . o
u~
~ ¦.. . ~ . . g
" ~ D O
co r~ ~ ~ O
O~In ~_I ~ ~ ~
~ r OD OU~1` 8
U) O1`~DO o
: o~
R ~ ~ v R
, @ ~ 8
IR~ 19,528
;~ ~5~i85
-38-
E~LE 28
The following polymer polyol dispersion was
produced usi~g the procedure described in Exam~le 1:
400 g of polyol D were heated under nitrogen to
125C~ A mixture of 93G g of acrylonitrile, 240 g of
styrene, 18 g of AIBN, 1400 g of polyol D, 400 g of
toluene, 30 g of AS and 42 g of TEA, produced by mixing
the individual components in this order, was added over
a period of ~ hours, the temperature being kept constant
lQ at 125C after an initial rise to 132C. After stirring
for 2 hours at the same tempe~ature, the toluene was
distilled off together with the residual monomers in a
water jet vacuum at 130C. The distillate collected in
a dry ice trap weighed 438.4 g and, according to analysis
by gas chromatoaraphy, contained 1.27% of styrene,
corresponding to 5.6 ~, and 7.7~ of acrylonitrile,
corresponding to 33.7. This gives a monomer conversion
of 96.7% and a solids content of 39.2~. The solid
contained 77.2% of bound acrylonitrile and 20.2% of
bound styrene. The hydroxyl number amounted to 34.6,
the acid number to 1.3 and the viscosity at room temper-
ature to 2850 mPas. The product was a yellowish, uniformly
finely divided dispersion free from nonfilterable components.
50 parts of this dispersion were diluted with 50
parts polyol D and the resulting mixture reacted with pure
2,4-diisocyanatotoluene to form a pre-polymer having an
NCO content of 3.15~. Hardening was carried out with
diethyl tolylene diamine at an NC~/NH2-index of 110. A
similar product was prepared with pure polyol D as sole
hydroxyl component. ~he following mechanical properties
were dete~mined on test specimens of the two elastomers
which had been tempered for 24 hours at 110C:
LeA 19,528
~15i3~85
-39-
Comparison Polymer poly-
test ol according
Polyol to the
_ D invention
Tensile strength ~DIN 53 504) 9.1 Mpa 25.1 Mpa
Elongation
at break (DIN 53 504) 400 % 445 %
Tear propagation
resistance (DIN 53 515) 16.9 KN/m 38.5 KN/m
Hardness, Shore A (DIN 53 505) 77 87
Elasticity (DIN 53 512) 55 % 52 %
LeA 19,528
,8~5
40--
~X~LES 28-33
The follo~ing tests were carried out by the
method described in Example 1. The quantities of
the materials used are given in grams. The reaction
temperature was 125C.
Example No. 28 29 30 31 32 33
Produc~ initially
introduced:
Polyol A 70 70 60 60 50 50
Polyol G 105 105 90 90 75 75
Toluene 25 25 25 25 25 25
Mixture introduced:
Polyol A 210 210 180 180 150 150
Polyol G 315 315 270 270 225 225
Toluene 50 50 50 50 50 50
Acrylonitrile140 150 190 200 235 250
Styrene 150 150 200 200 250 250
~lethacrylic acid 10 - 10 - 15
Triethyl amine 12 - 12 - 18
AIBN 3 3 4 4 5 5
Monomer Conversion(%)96.2 96.9 97.1 95.9 95.5 96.8
Acrylonitrile bound45.5 49.247.0 48.9 45.7 48.9
Styrene boundl)51.0 50.8 50.5 51.1 51.0 51.1
Acrylonitrile
(distillate) (~)12.9 13.6 11.8 14.7 12.0 13.3
Styrene
(distillate) (%)4.3 4.2 6.1 4.7 4.25 2.7
Polymer content (%)29.2 29.339.3 39.C 48.85 ag.2
Hydroxyl nu~er245.8 244 207.5 208.9 176 175
Non-filterable
componer,t (based on
solids) - lOO,um mesh 2
(0) - 14 ) ~o.~-) n.d. ~o.i2) n-d-
Viscosity (mPas) 3900 7000 7100 - 11800
)based on the polymer content 2! after 1:1 dilution
~ith toluene n.d. = not determined
385
- 41 -
~ he products of Examples 2S, 30 and 32 were
finely divided and completely or substantially free
from relatively coarse agglomerate particles. This
was also confirmed by the running of a sample down a
clean pla.e of glass, resulting in the formation of
a thin, uniformly translucent, film. Example 29
produced a preparation heavily permeated by agglom-
erates whilst Examples 31 and 33 produced viscous
sritty compositions whose viscosity was estimated
at more than 100,000 mPa.s and was not measured.
The products of Examples 28, 30 and 32 were
processed in a standard formulation for integral
skin rigid foam using com~ercial diphenyl methane
diisocyanate to form mouldings increasing in thick-
ness in steps. No surface voids occurredi the
resulting mouldings had a smooth, streak-free surface
and were distinguished by improved thermal stability
under load and an increased E-modulus.
EXA~IPLES 34-38
The following testSwere carried out in
accordance with Example 1. The reaction temperature
was 130C in each case.
Example ~lo. 3~ 35 _ 36 37 38
Product initially
introduced:
Polyol D 200 200 200 100 100
Mixture introduced:
Polyol D 400 400 400 400 300
Toluene 125 125 125 125 125
Acr~lonitrile 240 240 160 300 360
Styrene 150 145 220 190 215
AS 10 - - - 25
~AS - 15
~SA - - 20 10
_ _ 49.4
i~5`~85
-42
~xa~ le No. 34 35 36 37 38
-
T~ 14
TETA - - - 30.4
DBA - 22.5 - - 44.8
AIB'.~ 4 4 6 5 9
Monomer conversion (%) 94.9 96.3 97.0 95.8 96.8
Acrylonitrile boun21) 58.5 59.2 38.8 59.2 59.4
Styrene bound ) 38.8 36.9 56.0 38.7 26.3
Acrylonitrile in the
distillate (%) 20.3 16.8 14.6 11.3 18.2
Styrene in the
distillate (~) 2.9 4.1 3.8 3.1 5.2
Polymer content (~)39.6 40.2 41.8 50.4 60.4
Hydroxyl number 33.6 33.6 32.8 46.9 22.7
t~Gn-filterable component
based on solids - lOOl~m
mesh - (~) after 1:1
dilution with toluene ~ 0.1 ~ 0.11.2 ~ 0.1 0.8
EX~IPLE 39
10,000 g of polyol H were initially introduced
into a reac'ion vessel equipped with a stirrer, reflux
condenser, gas inlet pipe, temperature sensor and
metering unit, after which the air was displaced by
nitrogen and the contents of the vessel were heated
with stirrins under nitrogen to a tem?erature of
125C. .~ mixture of 30,000 g of polyol H, 24,000 g
of acrylonitrile, 15,200 g of styrene, 800 g of
acrvlic acid, 1120 g of triethyl amine, 400 g of
AIBN and 4000 g of toluene was then introducea over
a period of 7 hours by means of a membrane pump
(metering rate approximately 200 ml/minute). On
completion of the addition, the mixture was stirred
for 4 hours at 125C and then stripped at the same
temperature under a vacuum of 2 mbar. The distillate
was collectec in a receiver cooled with dry ice/acetone
followed by a ccld trap. After 11 hours, strippina
115~85
-43-
was terminated and the product - a pale yellow finely
divided dispersion - was drained off still hot
through a 100 ~m mesh sieve. In order to characterize
the product, the following data were determined
or calculated from measured values:
Quantity of distillate 5115 g
including acrylonitrile 18.6%
styrene 3.2%
acrylic acid 0.1%
triethylamine traces
Monomer conversion 97.2%
Acrylonitrile bound ) 57.6%
Styrene bound 1) 37.6
Solids content 50.0%
Sieve residue 1) 0.03%
Hydroxyl number/acid number 14.3/1.7
Viscosity at 24C 11,800 mPa.s
1) based on total solids content
EXAMPLES 40-43
" ~
The following formulations were foamed in a
Hennecke* type UBT 78 high-pressure foaming machine.
Polyol I is a polyether triol of polyoxypropylene
and terminal polyoxyethylene sequences, started
with trime~hylol propane, which contains 13% of
ethylene oxide and has a molecular weight of 4800 and
a hydroxyl number of 35. The two polymer polyols
used were produced semi-continuously in a 400-litre-
capacity stirrer-equipped vessel in accordance with
Examples 4 and 5 and corresponds in all their
analytical data to the products obtained in those
Examples. The quantities are quoted in parts by weight.
* Trademark
LeA 19,528
~'
~ 44 ~
r ~ple ~o. 40 41 ~2 ~3
Pol~er polyol of Example 2 100 50 - -
Polymer poly~l of ~xample 3 - - 100 50
Polvol I ~ 50 - 50
Water 4.0 ~.0 4.0 4.0
Polysiloxane stabiliser 1.2 1.2 1.2 1.2
Triet-ylene diamine 0.050.05 0.05 0.05
Dimethyl ethanolamine 0.2 0.2 0.2 0.2
Tin dioctoate 0.3 0.3 0.3 0.3
Tolylene diisocyanate
containing 80~ by weight of
the 2,4-isomer 24.5 24.2 22.8 23.4
Tolylene diisocyanate
containing 65~ by weight of
the 2,4-isomer 24.5 2g.2 22.8 23.4
NCO/OH index 105 105 105 105
Polyol input (kg./min.) 26 28 26 28
Rise time (sec.) 60 60 55 65
Gel time (sec.) 200 155 180 105
Testing of the mechanical properties produced the
follo~ing values:
Example ~o 40 41 42 43
Unit weight (kg/~
DIN 53 420 26 27 25 26
Tensile strength (kPa)
DIN 53 571 115 100 120 95
Breaking elongation (%)
DIN 53 571 120 155 80 120
Compression hardness at
40% deformation (kPa)-
DIN 53 577 7.1 4.4 11.0 5.8
The approximately 2 m long and 1 m wide foam blocks
were free from faults such as, for example, base bubbles,
cracks or voids. During ageing in the absence of heat
and moisture, no above-average deterioration in properties
was observed. All the foams readily lend themselves to
high-frequency welding to polyamide fabric.
385
- 45 -
~,,YA1`5~LE 4 q
~ hishly elastic foam was produced ir accordance
with the following formulation in the foarming machine
mentioned in the preceding Examples:
Polymer polyol o~ Example 4 50 parts by weight
Polvol I 50
Water 4-0
Triethylene diamine 0.2
Tin dioctoate 0.4 "
Silicone stabiliser 0.8 "
Diethanolamine 1.5
Tris-2-chloroethyl phosphate 2.0 "
Tolylene diisocyanate containing 30%
by weight of the 2,4-isomer50.6
NCO/OH index 105
Input of polyol 28 kg./min.
Rise time 49 secs.
The fo'.lowing mechanical properties were
determined on the foam:
Unit weight 26 kg/m3
Tensile strength 115 kPa
Breaking elongation 115
Compression hardness at
40~ deformation 4.1 kPa
This foam could also be effectively high-frequency
welded to polyamide fabric.
EXAMPLE 45
Mouldings of integral rigid foam were produced
in a Hennecke type HK 100 high-pressure foaming
machine using a plate mould measuring 900 m~ long x
450 mm wide x 10 mm thick. The following formulations
were foamed (quantitie~ in parts by weight):
A ~ C
Polymer polyol of Ex~mple 13 60 60
Commercial polyo - - 60
~solids content 20~)
~ 5
- 46 -
A B C
Polyol I 3 3 3
Ethylene glycol 25 25 25
Ethylene diamine/propylene oxide
adduct 1.5 1.5 1.5
Fatty-acid-based surfactant 7 7 7
Silicone stabiliser
Organometallic activator 0.1 0.1 0.1
Phosphorus-containir.g
flameproofing preparation 20 30 20
Trichloromonofluoromethane 8 8 8
The isocyanate component was a diphenylmethane-
diisocyanate containing polymeric fractions which
had been obtained by distilling off part of the
binuclear co~ponent from 'he crude phosgenation
product of an aniline-formaldehyde condensate. It
was used in quantities corresponding to an NCO/OH
index of 110. A11 of the formulations could be
foamed satisfactorily and without difficulty. The
mouldings had a smooth, bubble-free surface, free
from eddies and flow marks, ar.d a fault-free
foamed core. The following mechanical values were
determined:
A B C
Gross density (g/cc) 596 616 623
E-modulus in flexure (mPa) 1049 1012 435
Tensile strength (mPa) 14.3 13.1 11.7
Brea~ing elongation (%) 86.6 17.4
E-modulus in elongation (mPa) 634607 372
Heat distortion te~.perature (C) 96 83 71
DIN 53 432
These data illustr2'e the advantages of using
polymer polyols having high polymer contents such as
can be produce~ in accordance with the present
invention.
~S~;S8S
- 47 -
EX~'~LEa 46 to 55:
The following formulations were foamed in a
laboratory mould (aluminium, capacity 4 litres,
dimensions 20 x 20 x 10 cm). To carry this out,
the components of the formulation, other than the
isocyanate, ~ere stirred to~ether in a cardboard
container using a high-speed blade stirrer (2000
r.p.m.). After 60 seconds, the isocyanate was
added and, after stirring for another 10 seconds,
the mixture was poured into the mould the cover
of which was held down by clips. After a residence
time in the mould of 3 to 5 minutes, the mouldings
were removed and compressed once to open the cells.
The quantities quoted in the Table represent parts
15 by weisht.
Example No. 46 47 48 49
Polymer of polyol of Example 2 25 - 25
Polyol H 75 50 75 50
Commercial polymer polyol
(solids content 20%) - 50 - 50
Polymer content of the
polyol ccmponent 10 10 10 10
Water 2.9 2.9 3.6 3.6
Commercial amine activator 0.72 0.72 0.82 0.82
Commercial organometallic
catalyst 0.02 0.02 0.02 0.02
Commercial polysiloxane
stabiliser 1.1 1.1 0.9 0.9
Polyisocyanate of Example 45 35.6 35.6 44.8 44.8
NCO/OH-index 100 100 100 100
~15~
- 48 -
Exam~le No. 50 51 i2 53
.
Pol~mer polyol of Example 2 37.5 - 37.5
Polyol ~ 62.5 25 62.5 25
Commercial Pol~er polyol
(solids content 20%) - 75 - 75
Polymer content of the
pol~ol component 15 15 15 15
Water 2.9 2.9 3.6 3.6
Commercial amine activator 0. 72 0. 72 0. 82 0. 82
Commercial organometallic 0~ 02 0 . 02 0.02 0.02
catalyst
Commercial polysiloxane1.1 1.1 0.9 0.9
stabiliser
Polyisocyanate of Example 45 35.6 35.6 44. 7 44.7
NCO/OH-index 100 100 100 100
Example No. 54 55
Polymer polyol of Example 2 50
Polyol H 50
Commercial polymer polyol - 100
(solids content 20%)
Polymer content of the 20 20
polyol component
Water 2.9 2. 9
Commercial amine activator 0. 72 0. 72
Commercial organometallic 0. 02 0. 02
catalyst
Commercial polysiloxane1.1 1.1
stabiliser
Polyisocyanate of Example 45 35.3 35.3
~CO/OH-index 100 100
S
-- 49 -
~ he physical values set out in the follo~in~
Ta~le were determined for the foam mouldings. The
different gross densities for the same water
contents in the formulation are attributable to
different inputs of the foam mixture. In these
cases, compression hardness may be compared by
standardisation to a single unit weight. The
corresponding values are also shown in the Table.
Comparison of the polymer polyol of Example 2
with the commercial polymer olyol for the same
amount of polymer in the formulation shows that the
former is slightly to distinctly superior in its
mechanical properties. So far as the optical
~uality of the mouldin~s (homogeneity, freedom
from edge and internal cracks, cell structure and
skin formation) is concerned, no differences
were observed.
Example No. 46 47 48 49 50
3 _
Gross density (kg/m )
DIN 53 420 44 42 37.532 44
-Tensile strength (KPa)
DIN 53 571 190 165 180 155 200
Breaking elongation (%) 170 155 150 140 160
Compression hardness at
40% deformation (KPa)
DIN 53 577 4.8 4.3 5.43.6 5.6
Compression set (%)
DIN 53 572
at 90~ compression 7.6 - 9.8 - 9.4
at 50~ compression - 4.9 - 8.2
Compression nardness
comparison by standardisation
to a sin~le unit weight: 3
unit weight (~.g~m ) 44 44 37.5 37.5 44
compression hardness (KPa) 4.8 4.7 5.4 4.7 5.6
t~ 5
- 50 -
ExamPle No. 51 52 53 54 55
Gross density (kg/m )
DIN 53 420 40 38 32 43 40
Tensile strength (KPa)
DIN 53 571 200 215 175 210 200
Breaking elongation (%)150 145 125 145 135
Compression hardness at
40~ deforr,lation (XPa)
DIN 53 577 4.2 6.5 4.7 6.3 4.8
Compression set (~0)
DIN 53 572
at 90% compression - 13 - 3.7
at 50. co~.pression 6~0 - 6.3 - 7.3
Co~.pression nardness
comparison by standardisation
to a single unit weight: 3
unit weight (kg/m ) 44 38 38 43 43
compression hardness (KPa) 5.0 6.5 5.9 6.3 5.4
E~LES 56 to 59
The polymer polyol of Example 3, formulated with
polyol H to a solids content of 10%, was also compared with
the similarly adjusted commercial polymer polyol. The
components of the fGrmulation not specified correspond
to those in Examples 46 to 55. The quantities are again
quoted in parts by weight.
Example No. 56 57 53 59
Polymer polyol Gf Example 3 25 - 25
Polyol H 75 50 75 50
Commercial polymer polyol - 50 - 50
Water 2.9 2.9 3.6 3.6
Polyisocyanate 36.4 36.4 45.645.6
NCO/OH index 100 100 100 100
Gross density (kg/m3) 45 42 35.5 32
Tensile stren~th (KPa) 205 155 175 155
Brea~in~ elongation (%)160 155 140 140
Compression hardness at
40O compression (KPa) 5.0 4.2 5.5 3.6
Compression hardness for
standard unit weighl 3
Unit weisht (kg/m )45 45 35.535.5
compression hardness (~Pa) ~ n ~ R
B85
- 51 -
In tnis test series, too, equally good mouldings
were obtained from the polymer polyol according to the
invention and the co~mercial polymer polyol without
any foaming problems in either case. Once asain,
the polymer polyol according to the invention is
slishtly superior in its mechanical properties.
EXAMPLES 60 to 63
~eat-setting moulded foams were produced in a
4-litre mould in the same way as in the preceding
Examples. The following formulations were used
(quantities in parts by weight):
Example No. 60 61 62 63
Polymer polyol of Example 20 25
Polymer polyol of Example 21 - 25 - -
Polymer polyol of Example 24 - - 17
Polyol C 75 75 93 100
Polymer content of polyol (O) iO 10 10 10
~,~iater 3-4 3 4 3 4 3 4
Commercial amine activator0.20.2 0.2 0.2
Tin dioctoate 0.1 0.1 0.1 0.1
Silicone stabiliser 1.0 1.0 1.0 1.0
Tolylene diisocyanate
containing 80% of the
2,4-isomer
Index 102 102 102 102
Mechanical testing produced the following values:
Example No. 60 61 62 63
... _ ~ __
Unit weight (kg/mJ) 30 30 30 30
Tensile strength (KPa) 130 125 120 110
Breaking elongation (%) 180 165 125 180
Compression hardness at 40%
compression (KPa) 4.4 4.7 5.3 3.7
Compression set
90% compression (~) 4.7 5.3 6.2 3.5
All the mouldings had open cells and ~!ere free
from internal cracks, voids and skin faults.
