Note: Descriptions are shown in the official language in which they were submitted.
CA 02354240 2001-07-27
1
Preparation of polyetherols
The present invention relates to a ptocess for the preparation of
polyetherols based on solid initiator substances and liquid,
hydroxyl-containing coinitiators by a catalyzed addition reaction
of alkylene oxides and to the use of these polyetherpolyvls for
the preparation of polyurethanes (PUR), in particular rigid BUR
foams.
The preparation of polyetherols by anionic polymerization has
long been known.
Further details in this context appear, for example, in
1S Kunststoffhandbueh, Volume VII, Polyurethane, Carl-Hanser-Verlag,
Munich, 1st Edition 1966, edited by Dr. R. Vieweg and Dr. A.
Hdchtlen, and 2nd Edition 1983 and 3rd Edition 1993, edited by
Dr. G. Oertel.
Use of, for example, mono-, di- or polysaccharides and further
compounds having a high functionality in the preparation of
polyetherols having a high functionality for rigid PUR foams has
been widely described. when substances having a high content of
hydroxyl groups, for example sucrose, are used, the problem of
the reaction of solid substances with alkylene oxides in a
pressure autoclave occurs. Moroever, the use of high temperatures
during the alkoxylation reaction is limited. Thus, dark products
which are undesirable in numerous applications are formed in the
reaction of sucrose with alkylene oxides at above 120°C.
A process for the alkoxylation of solid initiator substances,
e.g. pentaerythritol, dipentaerythritol, trimethyloipropane,
sorbital or sucrose, is described in US-A-3346557. There, the
initiator substance containing from 3 to 8 OH groups per mole is
mixed with an amine catalyst and is alkoxylated to give an adduct
consisting of a usually solid compound containing from 3 to 8 OH
groups per mole, and from 0.5 to 1.5 mol of vicinal alkylene
oxide. For example, sucrose, tributylamine and distilled Water
are mixed and propoxylated. This adduct is stripped, mixed with
tributylamine and further propoxylated. The sucrose/propylene
oxide adduct serves as a reaction medium for taking up further
sucrose during further reaction with alkylene oxides.
However, it has been found that dark products are formed
~5 throughout as a result of the long thermal stress in the course
of the reaction. The introduction of sucrose into an alkoxylate
and further alkoxylation of this mixture furthermore often leads
CA 02354240 2001-07-27
2
to incomplete conversion of the sucrQSe added. Free sucrose is
present in the polyetherol and is deposited on the bottom. This
effect is very highly dependent on the degree of alkoxylation and
on the technical equipment of the production plant. As a result
of the amine catalysis, these polyetherols have high intrinsic
reactivities which adversely affect the curing of the foams and
greatly limit their use.
DD-A-211797 describes a process for the stepwise preparation of
polyetherols using solid or highly viscous initiator substances
in combination with substances which have a combined function as
catalyst and coinitiator, for example ammonia and/or its
propoxylation products. Far example, aqueous ammonia solution,
aqueous potassium hydroxide solution and sucrose are mixed and
are gropoxylatad in a first reaction stage. The product is
stripped and reacted with further propylene oxide. The
incorporation of nitrogen-containing compounds leads to
reductions in viscosity with comparable functionality but also to
an increase in the intrinsic reactivity of the polyetherol and
hence to a deterioration in the curing behavior. The
functionality of the polyetherols is also greatly reduced by the
high water contents of the solutions of nitrogen-containing
compounds. These palyetherols cannot be used for many rigid foam
applications. The required distillation step furthermore leads to
a poor yield of the raw materials used. Furthermore, the
wastewater is polluted necessitating further technical measures.
The process described in DE-A-4209358 for the preparation of
p4lyether alcohals based on solid and highly viscous initiator
substances having hydroxyl, imino or amino functional groups
comprises adding aliphatic amines in an amount from 0.5 to 5~ by
weight, based on the Weight of the palyol, to the initiator
substance or mixture of initiator substances and then carrying
out a reaction with alkylene oxides. These polyols have low
gotassium contents and light colors. In this process, too, the
amine content of the polyol results in a higher intrinsic
reactivity with respect to isocyanates, which necessitates a
decrease in the amount of foaming catalysts and hence adversely
affects the curing behavior.
The processes described have not become decisively established to
date. When nitrogen-containing compounds are concomitantly used,
the intrinsic reactivity of the polyetherols is noticeably
increased in a manner undesirable for many applications and thus
adversely affects the curing behavior of the rigid foams. The
reaction of compounds having a high functionality, such as
sucrese, with alkylene oxides in their own alkoxylates leads to
CA 02354240 2001-07-27
3
polyetherols which have a high functianality and often contain
unconverted sucrose.
Numerous processes for the preparation of polyetherols having a
high functionality and based on sucrose use glycerol as a
coinitiator. This proven procedure leads to polyetherols Which
meet most property requirements. However, they do not exhaust the
possibilities of a higher effective functionality of sucrose
polyetherols having improved curing behavior and formation of a
highly dense network in the foam. The process presented in
US-A-5143941 for the preparation of energy-absorbing PUR foams
uses, inter alia, a polyetherol based on sucrose/dipropylene
glycol/propylene oxide having'a hydroxyl number of about 400 mg
KOH/g. In the case of this hydroxyl number, however, it is
necessary to reduce the effective functionality to about 3.5,
since the viscosity of the polyetherol would otherwise far exceed
10 Pa~s. Consequently the effect of a high network density and of
good flow behavior is no longer obtained in the case of such
polyols.
CA-A-2135352 describes the preparation of rigid foams having a
-good insulation effect in combination with good physical
properties, good demoldability and K factors. The formulation
contains, inter alia, a palyetherol based on sucrose/propylene
glycol/water and propylene oxide and a polyetherol based on
sucrose/propylene glycol/water and ethylene oxide and propylene
oxide. Since excessively high viscosities are generally obtained
by the combination of sucrose/propylene glycol and usual hydroxyl
numbers for rigid foam applications and the water content reduces
the functionality, the useability is subject to limits.
For the use of sucrose polyetherols having a high functionality
which possess advantageous processing viscosities, give rise to
improved flow behavior or contribute towards sufficiently high
network density in the foam and are light in color, novel
possibilities are being sought for improving the properties of
the foam itself and its processing, such as curing behavior,
demolding of the foams, mechanical properties, insulation
behavior and heat stability and for ensuring economically
advantageous use of the raw materials.
It is an object of the present invention to provide, for rigid
PUR foams having high network density and good mechanical
properties, polyetherols which, with a large number of functional
groups and relatively low viscosity, excellent properties and
good thermal stability, can be reacted with polyisocyanates and
conventional additives to give FUR foams. It is intended to use
CA 02354240 2001-07-27
4
economical raw materials and technologies and to achieve a high
property level fox use in rigid industrial foams for sandwich,
refrigerator and district heating applications.
We have found that this object is achieved, according to the
inveriti.on, if an initiator combination having ethaxy structures
is used for the preparation of the polyetherols, the ratio of the
mean number of hydroxyl groups per mole of initiator combination
to the number of ethoxy structures in the polyetherol being from
T:0.2 to 1:1.8 cad the ratio of the amounts by weight of the
ethoxy structures to the mean molecular weight of the polyetherol
being from 1:2 to 1:15.
The present invention thus relates to a process for the
preparation of polyetherols based on solid initiator substances
and liquid, hydroxyl-containing coinitiators by a catalyzed
addition reaction of alkylene oxides, wherein the initiator
combination contains ethoxy structures, the ratio of the average
number of hydroxyl groups per mole of initiator combination to
the number of ethoxy structures in the polyetherol being from
1:0.2 to 1:7..8 and the ratio of the amounts by weight of the
ethoxy structures to the average molecular weight of the
polyetherol being from 1:2 to Z:15. The present invention
furthermore relates to the polyetherols themselves prepared by
this process and to their use for the preparation of PUR, in
particular rigid PUR foams.
Rigid PUR foams having good properties are obtained with the use
of polyetherols based an sucrose-diol or diol/triol having ethoxy
groups. =t was found that the effective functionality of the
polyetherols, with identical average functionality of the
initiator mixtures, based on the average number of functional
groups per mole, is highest when the difference between the
numbers of the hydroxyl. groups of the substances in the i.nitiatoz
mixture likewise reaches or closely approaches its highest
possible value.
It was found, surprisingly, that the use of ethoxy structures ire
addition to, for example, sucrose in the initiator mixture
influences the polyetherol properties mute greatly than expected.
Thus, it was primarily possible to improve the curing behavior
and the flowability substantially. An unexpectedly large effect
was found in particular when ethoxy structures are present both
in the initiator mixture and in the chain structure. This
combination enhances in particular the reduction in the viscosity
CA 02354240 2001-07-27
of the polyetherol mixture as well as substantially improving the
flow behavior during foataing.
According to the invention, the solid initiator substance used is
5 preferably sucrose. However, it is also possible to use, for
example, sorbitol and, if required, pentaerythritol.
In the case of solid initiators, the presence of liquid,
hydroxyl-containing coinitiators is necessary in order to take up
the solid, thoroughly mix it and alkoxylate it.
According to the invention, ethoxy--carrying, preferably
difunctional coinitiators and/or their di- or tricondensates are
used. Advantageously used coinitiatars are ethylene glycais.
Mono-, di- and triethylene glycol and any desired mixtures
thereof are suitable.
If required, water is used in addition to said coinitiators.
The content of solid initiators in the initiator mixture is
preferably from 35 to 90, particularly preferably froth 70 to 65,
% by weight.
In addition to the novel ethoxy-carrying diols, if appropriate up
to 10~ by weight, based on the total weight of the coinitiators
used, of further conventional coinitiators, for example propylene
glycols and/or triols, such as glycerol and trimethylalpropane,
may be present.
The functionality of the initiator mixture is preferably from 3.5
to 6, particularly preferably from 4 to 5.
,_ For the preparation of the polyetherols, the mixture of solid
initiator substances and liquid, hydroxyl-containing coinitiators
is reacted with alkylene oxides.
Lower alkylene oxides, advantageously ethylene oxide, propylene ,
oxide and/or butylene oxide, are preferably used for the
alkoxylation reaction. The alkylene oxides are subjected to the
addition reaction individually, in succession in blocks or in the
form of random mixtures.
The reaction of the initiator mixture with propylene oxide alone
or the formation of a low molecular weight propoxylate, Which is
~5 subsequently reacted with defined amounts of ethylene oxide, is
advantageous. Thereafter, further propylene oxide and/or butylene
CA 02354240 2001-07-27
6
oxide can be added until the desired mo~.ecular weight o~ the
polyetherols is reached.
Further advantageous process variants are the metering of an
ethylene oxide-containing mixture of alkylerte oxides and a
further addition reaction of propylene oxide or butylene oxide as
terminal block.
If ethylene oxide is used, its amount is advantageously up to 30,
ZO preferably from 10 to 15, mol%, based in each case on the
molecular weight of the polyetherol.
The alkoxylation is carried ont in a known manner, as explained,
for example, fuxther below. The reaction is effected in
is particular at from BO to 140°C and from 0.1 to 1.0 MPa and is
anionically or cationically catalyzed, preferably with basic
catalysts, such as amines or alkaline earth metal or alkali, metal
hydroxides. potassium hydroxide is particularly preferably used
as a catalyst.
2Q
In order to obtain polyetherols having the advantageous
properties described above, according to the invention a ratio of
the average number of hydroxyl groups per mole of initiator
combi~nati.on to the number of ethoxy structures in the polyetherol
25 of from 1:0.2 to 1:1.8, preferably from 1:o.3 to 1:1.5, and a
ratio of the amounts by weight of the ethoxy structures to the
average molecular weight of the polyetherol of from 1:2 to 1:15,
preferably Pram 1:3.5 to 1:11, should be maintained.
30 If the number of ethoxy structures in the polyetherol is below
these limits, the desired advantageous effects which the
polyetherols have on curing behav~.or and flawability when used as
components in the polyurethane system are no longer present. In
the case of contents of ethoxy structures above said limits,
35 primary Ot3 groups are increasingly farmed and the reactivity
inCre ' °~~~-~ ~r~i i v_
aSe3 uitiiawc~a~.,....,.,.._~j _
The content o~ ethoxy structures results from the ethylene
glycols in the initiator mixture but may be additionally
40 increased by the use of ethylene oxide.
The content of ethoxy structures is also variable as a result of
the possible use of condensed products of ethylene glycol, use up
to the tricondensate being expedient.
' CA 02354240 2001-07-27
7
After the end of the alkylene oxide addition reaction, the crude
polyetherpolyoi is separated from the catalyst in a known manner,
for example by neutralization with an acid, distillation under
reduced pressure and filtration.
The polyetherpolyols thus prepared can, if required, be further
purified by conventional methods, for example extraction or
sorption With solid sorbents or extracting agents, although this
is not necessary for achieving the object of the invention.
The polyetherols prepared according to the invention have an OH
number range of from 300 to 650 mg RoH/g. The advantageous
properties are displayed in particular in the OH number range
from 380 to 520 mg ROH/g, so that these products are preferred
is for use in practice.
They have a functionality of from 3.5 to 6. Owing to the high
functionalities achievable in the case of the novel polyetherols,
an important precondition for the formation of highly crosslinked
rigid foams having good mechanical stability, and owing to well
balanced flow and curing behavior, these products are very useful
for the preparation of industrial rigid pUR foams.
The preparation of the PUR, in particular rigid pUR foams, is
effected in the usual manner by reacting the polyetherols
prepared according to the invention, if required as a mixture
with further higher molecular weight compounds having at least
two reactive hydrogen atoms, with organic and/or modified organic
polyisocyanates and, if required, low molecular weight chain
extenders and/or crosslinking agents in the presence of blowing
agents, catalysts and, if required, further assistants and/or
additives.
Regarding the starting components known per se which may be used,
it may be stated specifically:
Suitable organic and/or modified organic polyisocyanates are the,
aliphatic or cycloaliphatic, araliphatic and preferably aromatic
polyfunctional isocyanates known per 5e.
Specific examples of alkylene diisocyanates having 4 to 12 carbon
atoms in the alkylene radical, such as dodecane
1,12-diisocyanate, 2-ethyltetramethyleae 1,4-diisocyanate,
2-methylpentarnethylene 1,5-diisocyanate, tetramethylene
1,4-diisocyanate and preferably hexamethylene 1,6-diisocyanate,
cycloaliphatic diisocyanates, such as cyclohexane 1,3- and
1,4-diisocyanate and any desired mixtures of these isomers,
' CA 02354240 2001-07-27
8
1-isocyanato-3,3,5-trimethyl--5-isocyanatomethylcyclohexane
(IpDI), hexahydrotolylene 2.4- and 2,fi-.diisocyanate axed the
corresponding isomer mixtures, dicyclohexylmethane 4,4'-, 2,2'-
and 2,4'.-diisocyanate and the corresponding isotaer mixtures, and
S preferably aromatic di-- and polyisocyanates, e.g. tolylene 2,4-
and 2,6-diisocyanate and the corresponding isomer mixtures,
diphenylmethane 4,4'-, 2,4'- and 2,2'-diisocyanate and the
corresponding isomer mixtures, polyphenylpvlymethylene
poiyisocyanates, mixtures of diphenylmethane 4,4'-, 2,4'- and
i4 2,2'-diisocyanates and polyphenylpolymethylene polyisocyanates
(crude MDI) and mixtures of crude MDI and tolylene diisocyanates.
The organic di- and polyisocyanates can be used individually or
in the form of their mixtures:
15 Frequently, modified polyfunctional isocyanates, i.e. products
which are obtained by chemical reaction of organic di-- and/or
polyisocyanates, are also used. Examples are di- and/or
polyisocyanates containing ester, urea, biuret, allophanate,
carbodiiniide, isocyanurate, uretdione and/or urethane groups, The
20 modified polyisocyanates can be mixed with one another or with
unmodified organic polyisocyanates, e_g. diphenylmethane
2,4'-diisocyanate, diphenylmethane 4,4'-diisocyanate, crude MDI,
tolylene 2,4-diisocyanate and/or tolylene 2,6-diisocyanate.
25 In addition to the novel polyetherpolyols described above,
further caaspounds having hydrogen atoms reactive toward
isocyanates can, if required, be used.
Compounds hava.ng at least two reactive hydrogen atoms axe
30 primarily used for this purpose. Expediently, Chase having a
functionality of from Z to 8, preferably from 2 to 6, and a
molecular weight of from f00 to 8000, preferably from 300 to
._ 3000, are used. Use depends on the desired properties of the
rigid PUR foam to be prepared.
:'or ex~sple, it is possible to use further polyols selected from
the group consisting of polyetherpo7.yols, polyesterpoiyols,
polythioetherpolyals, polyesteramides, hydroxyl-containing
polyacetals and hydroxyl-containing aliphatic polycarbonates, or
mixtures of at least two of said polyois. The hydroxyl number of
the polyhydroxy compounds is as a rule from 150 to 850,
preferably from 200 to 600, mg KOH/g. For example, polyether
polyamines may also be used.
The polyetherpolyols used are prepared by known processes, for
example by anionic polymerization with alkali metal hydroxides,
e.g, sodium hydroxide or potassium hydroxide, or alkali metal
CA 02354240 2001-07-27
9
alcoholates, e,g. sodium methylate, sodium ethyiate, patassium
ethylate or potassium isapropylate, as catalysts and with the
addition of at least one initiator which contains from 2 to 8,
preferably from 2 to 6, bonded reactive hydrogens per molecule,
or by cationic polymerization with Lewis acids, such as antimony
pentachloride, boron fluoride etherate, etc., or bleaching earths
as catalysts, from one or more alkylene oxides having 2 to 4
carbon atoms in the alkylene radical.
ZO Other suitable polyetherpolyols are polymer-modified
polyetherpolyols, preferably graft polyetherpolyols, ih
particular those based an styrene and/or acrylonitrile, which are
prepared by in situ polymerization of acrylonitrile, styrene or
preferably mixtures of styrene and acrylonitrile, far example in
the weight ratio of from 90:10 to 10:90, preferably from 70:30 to
30:70, expediently in the abovernentioned polyetherpolyols,
analogously to the data of German patents 1111394, 1222669
(US 3304273, 3383351, 3523093), 1152536 (GB 1040452) and 1152537
(GB 987618), and polyetherpolyol dispersions which contain, as
ZO the disperse phase, usually in an amount of from 1 to 50,
preferably from 2 to 25, % by weight, for example polyureas,
polyhydrazides, polyurethanes containing bonded tart-amino groups
and/or melamine and which are described, for example, in
EP-8-011752 (US 4304708), US-A-4374209 and DE-A-3231497.
2S
=f, in addition to the novel polyetherols, further higher
molecular weight compounds having at least two reactive hydrogen
atoms are used, the proportion of the novel polyetherpolyals
should be at least 25~ by weight. Advantageously, from 30 to 70%
30 by weight of novel polyetherpolyals are used, based in each case
on the total weight of the higher molecular weight compounds
having at least two reactive hydrogen atoms.
The PUR, in particular rigid FUR foams, can be prepared with or
35 without the uae of chain extenders and/or crosslinking agents,
although these are not generally required. The chain extenders
and/or crosslinking agents used are diols and/or triols having
molecular weights of less than 400, preferably from 60 to 300.
For example. aliphatic, cycloaliphatic and/or araliphatic diols
40 of 2 to 14, preferably 4 to 10, carbon atoms, e.g. ethylene
glycol, 1,3-propanediol, 1,10-decanedioi, o-, m- and
p-dihydroxycyclohexane, diethylene glycol, dipropylene glycol and
preferably 1,4-butanediol, 1,6-hexanediol and
bis(2-hydroxyethyl)hydroquinone, triols, such as 1,2,4- and
45 1,3,5-trihydroxycyclohexane, triethanolamine, diethanola.mine,
glycerol and trimethylolpropane, and low molecular weight
hydroxyl-containing polyalkylene oxides based on ethylene oxide
CA 02354240 2001-07-27
and/or J.,2--propylene oxide and the abovementioned diols and/or
triols as initiator molecules are suitable.
Tf chain extenders, crosslinking agents or mixtures thereof are
used, they are expediently used in an amount of up to 20,
preferably from 1 to 10, % by weight, based in each case on the
weight of the compounds having at least two xeactive hydrogen
atoms which are used.
For the greparation of PUR foams, blowing agents are usually
used. The blowing agent used in particular is water, which
eliminates carbon dioxide as a result of the reaction with the
isocyanate gxoups. The water content is preferably ~rom O.L.to 4,
in particular from 0.3 to 3, % by weight, based on the weight of
the compounds having at least two reactive hydrogen atoms which
are used.
Water may be added in combination with the use of physical
blowing agents.
The physical blowing agents used may be the chlorofiuoroearbons
(CFCs) generally known from polyu=ethane chemistry and highly
fluorinated andlor perfluorinated hydrocarbons. However, the use
of these substances is greatly restricted or has been completely
discontinued for ecological Reasons. In addiaion to
chlorofluorohydrocarbons and fluorohydrocarbons, in particular
aliphatic and/or cycloaliphatic hydrocarbons are possible as
alternative blowing agents. In particular, low--boiling
hydrocaxboas, lower monofunctional alcohols and acetals, e.g.
methylal, are used. how-boiling cyclic and acyclic saturated
hydrocarbons of up to 12 carbon atoms are preferred and can be
used individually or as any desired mixtures with one another. Zn
,. particular, pentanes are used, it being possible to use both
mixtures of the pentane isomers and the pure isomers. Owing to
the particularly lo~a thermal conductivities, cyclopentane is
particularly preferably used. These physical blowing agents are
usually added to the polyol component of the system. However,
they can also be added to the isocyanate component or both to the
polyol component and to the isocyanate component as a
combination. The amount of the physical blowing agent used or of
the blowing agent mixture is from 1 to 30, preferably from 5 to
20. % by weight, based in each case on the weight of the A
component defined further below.
Further assistants and/or additives are incorporated into the
reaction mixture for the preparation of the pUR. Examples axe
catalysts and, i.f required, surfactants, foam stabilizers, cell
CA 02354240 2001-07-27
SZ
regulators, fillers, dyes, pigments, flameproafing agents,
hydrolysis stabilizers and fungistatic and bacteriostatic
substances.
3 For the preparation of the PuR, 3n particular rigid. PvR foams,
the organic and/or modified organic polyisocyanates, the novel
polyetherpolyols and, i~ required, further compounds having
hydrogen atoms r~active toward isocyanates are reacted in amounts
such that the ratio of the number of equivalents of NCO groups of
the polyisocyanates to the sum of the reactive hydrogen atoms of
the novel polyetherpolyols and any further compounds having
hydrogen atoms reactive toward isocyanates is from 0.85:1 to
1.25:1, preferably from 0.95:1 to 1.15:1, in particular from 1:1
to 1.05:1. If the rigid pUR foams contain at least sums of the
isocyanurate groups in bonded form, the ratio of NCO groups of
the polyisocyanates to the sum of the reactive hydrogen atoms of
from 1.5:1 to 60:1, preferably from 1.5:1 to 8:1, is usually
used.
=t has proven particularly advantageous to employ the
two-component process and to combine the components
(polyetherpolyois prepared according to the invention, any higher
molecular weight compounds having at least two reactive hydrogen
atoms which are present, any low molecular weight chain extenders
and/or crosslinking agents which are present, blowing agents,
catalysts and any further assistants and/or additives inta a
polyol component, often also referred to as component A, and to
use the organic and/or modif led organic polyisocyanates and any
blowing agent as the isocyanate component, often also referred to
as component s.
Further information about the abovementioned and further starting
materials and about the PUR preparation is to be faund in the
technical literature, for example the monograph by J.H. Saunders
and x.C. Frisoh, ~~High pelymers~~, volume XVI, Polyurethanes,
Parts 1 and 2, Interscienae Publishers 1962 and 1964, or the
above-cited Kunststof~handbuch, Polyurethan~, Volume VII,
Hanser-Verlag Munich, Vienna, 1$t to 3rd Editions.
~0 The use of the novel polyetherols in rigid foam systems leads to
excellent curing and surprisingly large improvement in the
fiowability during foaming, with the result that application
advantages are achievable in the~industrial rigid foam, in
particular in the district heating application and in
~5 refrigeration, but also in the case of support and design
CA 02354240 2001-07-27
is
materials S.n the furniture nectar and in construction paxta is
the automotive sector.
The rigid kt7R foams prepared using the novel polyetherola have a
S density of from 0.02 to 0.30, preferably from 0.025 tv 0.24, in
particular ~rom 0.03 to 0.1, g/cm3.
The examples which follow illustrate the invention but without
imposing a corresponding restriction.
to
Example 1 (Comparison)
325 g o~ triethanolamine and 7 g o~ 45$ strength potassium -
hydroxide solution were initially taken into a 27. autoclave
15 having a stirrer, a temperature and pressure measurement means
and heating and cooling, and 320 g of sucrose were added while
stirring. The mixture was then heated to 110°C. 1135 g of
propylene oxide were then metered in at a reaction temperature of
from 110 to lI5°C and a pressure of from 4 to 6 bar. After a
20 subsequent reaction for 2 hours at 110°C, the arcade palyethervl
was cooled, hydrolyzed with water, neutralized with phosphoric
acid and then subjected to distillation under reduced pressure
and filtered.
25 The polyetheral obtained had the following Characteristics:
OH number 432 mg KOH/g
Viscosity at 25°C 7600 mPa~s
pH 10.0
30 Water content 0.04 by weight. '
Example 2 (comparison)
135 g of ethanolamine and 9 g of 95~ strength potassium hydroxide
35 solution were initially taken is an autoclave according to
Example 1, and 320 g of sucrose were added while stirring. The
mixture was then heated to 110°C. 1325 g of propylene oxide were.
then metered is at a reaction temperature of from 110 to 115°C and
a pressur~ of from 4 to 6 bar. After a subsequent reaction for Z
40 hours at il0°,C, the crude polyetherol was cooled, hydrolyzed with
water, neutralized with phosphoric acid and then subjected to
distillation under reduced pressure and filtered.
The polyetheral obtained had the following characteristics:
OH number 437 mg Koii/g
Viscosity at 25°C 7750 mPa~s
CA 02354240 2001-07-27
1~
pH 10.4
Water content 0.04% by weight.
Example 3 (comparison)
2a5 g of glycerol arid 9 g of 45% strength potassium hydroxide
solution were initially taken in an autoclave according to
Example 1, arid 360 g of sucrose were added while sorting. The
mixture was then heated to 110°C. 1215 g of propylene oxide were
t0 then metered in at a reaction temperature of from 110 to 115°C and
a pressure of from 3 to 6 bar. After a subsequent reaction for 2
hours at 110°C, the crude polyetherol was cooled, hydrolyzed with
water, neutralized with phosphoric acid and then subjected.to
distillation under reduced pressure and filtered.
i5
The polyetherol obtained had the following characteristicss
OH number 993 mg KOH/g
Viscosity at 25°C 8490 mpa~s
ao pH 8.3
wateF content 0.02% by weight.
Example 4 (according to the invention)
25 180 g of diethylene glycol and 9 g c~f 45% strength potassium
hydroxide solution were initially taken i.n an ~utvclave according
to Example Z, and 480 g of sucrose were added while stirring. The
mixture was then heated to 110°C. 1125 g of propylene oxide were
then metered in at a reaction temperature of from 7.10 to 115°C arid
30 a pressure of from 4 to 6 bar. After a subsequent reaction fox 2
hours at 110°C, the crude polyetherol was cooled, hydrolyzed with
water. neutralized with phosphoric acid and then subjected to
distillation under reduced pressure and filtered.
35 The polyetherol obtained had a ratio of the average number of
hydroxyl groups per mole of initiator combination to the number
of ethoxy structures in the polyetherol of 1:0.5 and a ratio of
the amounts by weight ef the ethoxy structures to the average
moleCUlar weight of the polyetherol of 1:6.8.
9, 0
The following characteristics were determined:
OH number 435 mg KOH/g
Viscosity at 25°C 5660 mpa~s
45 pH 8.6
Water content 0.071% by weight.
CA 02354240 2001-07-27
i4
Example 5 (according to the invention)
180 g of diethylene glycol and 9.5 g of 45% strength potassium
hydroxide solution were initially taken in an autoclave according
to Example 1, and 480 g of sucrose were added while stirring. The
mixture was then heated to 110°C. 270 g of ethylene oxide were
then added at a reaction temperature of from 105 to 110°C and a
pressure of from 4 to 6 bar. After a subsequent reaction time of
1 hour at 110°C. 830 g of propylene oxide were metered in at a
reaction temperature of from 110 to 115°C and a pressure of from 3
to 6 bar. After a subsequent reaction for 2 hours at 110°C, the
crude polyetherol was cooled, hydrolysed with Water, neutralised
with phosphoric acid and then~subjected to distillation under
reduced pressure and filtered.
she polyetherol obtained had a ratio of the average number of
hydroxyl groups per mole o~ initiator combination to the number
of ethoxy structures in the polyetherol of 1:1.4 and a ratio of
the amounts by weight of the ethoxy structures to the average
molecular weight of the polyetherol of 1:2.
The following characteristics were determined:
aH number 402 mg K4Fi/g
2g viscosity at 25°c 2050 mpa~s
pH 8.oa
Water content 0.03% by weight.
Example 6 (according to the invention)
127 g of monoethylene glycol and 9 g of 45% strength Potassium
hydroxide solution were initially taken in an autoclave according
to Example 1. and 480 g of sucrose were added while stirring. The
mixture was then heated to 110°C. il?5 g of propylene oxide were
then metered in at a reaction temperature of from 110 to 115°C and
a pressure of from 3 to 6 bar. After a subsequent reaction foz 2
hours at 110°C, the crude polyetherol was Cooled, hydrolyzed with
water, neutralized with phosphoric acid and then subjected to
distillation under reduced pressure and Filtered.
~a
The polyetherol obtained had a ratio of the average nuIr~ber of
hydroxyl groups per mole of initiator combination to the number
of ethoxy structures in the polyetheroi of 1:0.5 arid a ratio of
the amounts by weight of the ethoxy structures to the average
g,g molecular weight of the polyetherol of 1:5.6.
CA 02354240 2001-07-27
The following characteristics were determined:
OH number 491 mg KOH/g
Viscosity at 25°C 12080 mPa~s
pH 7.85
Water content 0.03% by weight.
Example 7 (according to the invention)
lA 307 g of triethylene glycol and 8 g of 45b strength potassiuas
hydroxide solution were initially taken in an autoclave according
to Example 1, and 500 g of sucrose were added while stirring. The
mixture Was then heated to 110°C. 1000 g of propylene ox~,de_~,rere
then metered in at a reaction temperature of from 110 to 115°C and
a pressure of from 3 to 6 bar. After a subsequent reaction for 2
hpurs at 110°C, the crude polyetherol was cooled, hydrolyzed with
water, neutralized With phosphoric acid and then subjected to
distillation under reduced pressure and filtered.
The polyetherol obtained had a ratio of the average number of
hydroxyl groups per mole of initiator combination to the nutaber
of ethoxy structures in the polyetherol of 1:0.9 and a ratio of
the amounts by weight of the ethoxy structures to the average
molecular weight of the polyetherol of 1:4.
The following characteristics were determined:
OH number 481 mg KoH/g
Viscosity at 25°C 9570 mPa~s
34 pit 9.71
Water Content 0.03% by weight.
Example 8 (according to the invention)
I90 g of diethylene glycol and 8.5 g of 45% strength potassium
hydroxide solution were initially taken in an autoclave according
to Example l, and 440 g of sucrose were added while stirring. The
mixture was then heated to I10°C. 450 g of propylene oxide were
then added at a reaction temperature of from 110 to I15°C and a
pressure of from 3 to 6 bar. After a subsequent reaction for 2
hours at 110°C. this prepolymer having the following
characteristics:
Viscosity at 75°C about 1000 rnPa~s
Total alkalinity about 0.34% of KOH
CA 02354240 2001-07-27
Z
was reacted with a further 690 g of propylene oxide. The crude
polyetherol was cooled, hydrolyzed with water, neutralized with
phosphoric acid arid them subjected to disti.liation under reduced
pressure and filtered.
The polyetherol~obtaiaed had a ratio of the average number of
hydroxyl groups per mole of initiator eombination to the number
of ethoxy structures iri the polyetherol of 1:0.8 and a ratio of
the amounts by weight of the ethoxy structures to the average
molecular weight of the polyetherol of 1:3.6.
The following characteristics were determined:
OH number 442 mg KOH/g
Viscosity at 25°C 6520 mPa~s
pg 7.96
Water content 0.01 by weight.
(The prepolymer was capable of being stored and could be used as
a starting material far further final syntheses in the main
reactor.)
Example 9 (according to the invention)
176 g of diethylene glycol and 10 g of 45~ strength potassium
hydroxide solution were initially taken in an autoclave according
to Example l, and 406 g of sucrose were added while stirring. The
mixture was then heated to 110°C. 230 g of ethylene oxide and
450 g of propylene oxide, as a mixture, were then metered in at a
xeaction temperature of from 110 to 115°C arid a pressure of from 3
to 6 bar. After a subsequent reaction for one hour at 115°C, a
further 530 g of propylene oxide were added. After a subsequent
reaction for 2 hours at 110°C, the crude polyetherol was cooled,
hydrolyzed with water, neutralized with phosphoric acid and then
subjected to distillation under reduced pressure and fi3.tered.
The polyetherol obtained had a ratio of the average number of
hydroxyl groups per mole of initiator combination to the number
of ethoxy structures in the polyetherol of 1:1.6 and a rat~.o of
the amounts by weight of the ethoxy structures to the average
molecular weight of the polyetherol of 1:2.
CA 02354240 2001-07-27
17
The following characteristics were determined4
OH autaber 404 mg IfoB/g
Viscosity at 2S°C 2280 mPa~s
PH 8.95
Water content 0.02$ by weight.
Example 10 (comparison)
A polyol component consisting of
59. parts by mass (pbm) of a polyetherol according to Example I,
having an OA number of 432 mg KOH/g, ,_,
4.2 pbm of glycerol,
21.1 pbm of a polyetherol based on monoethylene glycol and
propylene oxide, 08 number of 105 mg ROA/g,
1 pbm of sil~.cone stabilizer a 8409 (from Goldschmidt),
1.8 pbm of dimethylcyclohexylamine,
2.4 pbm of water and
15.5 pbm of R 141 b,
was thoroughly mixed with 125 pbm of crude MDI, NCO content 31.50
by mass (characteristic 110).
When subjected to free-rising foaming in the foam beaker, the
resulting foam had a density of 29.2 kg/m3
Example 11 (comparison)
A polyol component according to Example 10, but which contained
54 parts by mass (pbm) of a polyetherol according to Example 2,
having an off number of 43? mg KOH/g (instead of the polyetherol
according to Example 1), was thoroughly mixed with 125 pbm of
crude MLZ, NCO content 31.5 by mass (characteristic 110).
The resulting foam had a density of 30.0 kg/m3.
Example 12 (comparison)
A polyol component according to Example 10, but which contained
54 parts by mass (pbm) of a polyetheral according to Example 3,
having an OH number of 493 tng KOH/g (instead of the polyetherol
according to .Example 1), was thoroughly mixed with 125 pbm of
crude MDr, NCO content 31.5 by mass gcharacteristic 110).
The resulting foam had a density of 30.5 kg/m3.
' CA 02354240 2001-07-27
20
ss
Example 13 (according to the invention)
A polyol component according to Example l0, but which contained
54 parts by mass (pbm) of a polyetherol according to Example 4,
5 having an OH number of 435 mg KOH/g (instead of the polyetherol
according to Example 1), was thoroughly mixed with 125 pbm of
crude MDI, NCO content 31.5 by mass (characteristic 110).
The resulting foam had a density of 31.0 kg/m3.
Example 14 (according to the invention)
A polyol component according to Example 10, but Which contained
54 parts by mass (pbm) of a polyetherol according to Example 5,
15 having an off number of 422 mg gOB/g (instead of the polyetherol
according to Example 1), was thoroughly mixed with 125 pbm of
crude Mn=, NCO content 31.5% by mass (characteristic 110).
The resulting foam had a density of 30.2 kg/m~.
Example Z5 (according to the invention)
A polyal component according to Example Z0, but which contained
54 parts by mass (pbm) of a polyetherol according to Example 6,
25 having an OH number of 491 mg KOH/g (instead o~ the polyetherol
according to Example 1), was thoroughly mixed with 125 pbrn o~
crude MDI, NCO content 31.5b by mass (characteristic 110).
The resulting foam had a density of 31.5 kg/m3.
Example 16 (according to the invention)
A polyol component according to Example 10, but which contained
54 parts by pass (pbm) of a polyetherol according to Example 7,
having an OH number of 481 mg KOH/g (instead of the polyetherol
according to Example 1), was thoroughly mixed with 125 pbm of
crude MDI, NCO content 31.5b by mass (characteristic 110).
The resulting foam had a density of 31.0 kg/m3.
ExampXe 17 (according to the invention)
A polyol component according to Example 10, but which contained
54 parts by mass (pbm) of a polyetherol according to Example 8,
having an OH number of 442 mg KOH/g (instead of the polyetherol
CA 02354240 2001-07-27
15
19
according to Example 1), Was thoroughly mixed with 125 ~pb~xc of
Crude MDI, NCO Content 31.5 by mass (characteristic 110}.
The resulting foam had a density of 30.0 kg/m3.
Example 18 (according to the invention)
A polyol component according to Example 10, but which contained
54 parts by mass (pbm) of a polyetherol according to Example 9,
10 having an OH number of 404 mg KOH/g (instead of the polyetherol
according to Example 1), was thoroughly mixed with 125 p~srn of
crude MDI, NCO content 31.5 by mass (characteristic 110).
The resulting foam had a density of 29.5 kg/m9.
Thc~ foams obtained were investigated by means of the bolt test
with respect to their curing and by means of the tube test with
respect to their flowability.
z0 Bolt test
Using a standardized bolt of 20 mm diameter, the force of
penetration into the foam is measured at specific time intervals
after preparation. The bolt penetrates 10 mm into the foam.
Tube test
Immediately after mixing of the components, 100 g of reacting
mixture are poured into a continuous tube comprising a plastics
film having a diameter of 4.5 cm. The tube is then clamped off
and the foam length achieved is taken as a measure of the
flowability.
The results obtained are shown in Table Z.
Table 1
Example ~ 11 12 13 14 15 16 17 ~~18
10
.
Force of
0 penetration (N) .
after 3 min 13 10 15 28 30 25 28 30 35
after 5 min 40 35 42 60 61 55 58 62 65
Foam length (cm) 150 145 153 170 165 160 I ~ ~
163 I65 172
i
' CA 02354240 2001-07-27
The rigid PUR foams based on the navel polyols exhibited better
curing and better flow behavior compared with those based on the
comparative polyols.
io
t5
as
~35
~0
~5
