Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
~L~7~ 5
-1- Docket No. Wa-8107
- Paper No. 1
ORGANOPOLYSILOXANE COMPOSITIONS AND
ELASTOMERS FORMED THEREFROM
The present invention relates to organopolysiloxane
compositions and more particularly to room temperature vulcani-
zable organopolysiloxane compositions and elastomers prepared
therefrom.
Background of the Invention
j Compositions which can be stored under anhydrous
conditions, but when exposed to atmospheric moisture crosslink
I to form elastomers at room temperature containing a diorgano-
polysiloxane, an organosilicon compound having at least three
hydrolyzable groups bonded to the silicon atom per molecule and
~ containing at least another substance are described in U. S.
;1 Patent No. 4,230,826 to Sommer et al. The compositions described
in the patent consist of (1) an organopolysiloxane having terminal
condensable groups, (2) a silicon compound having at least 3 Si-
bonded hydrolyzable groups per molecule and (3) a powder obtained
~ from the homopolymerization or copolymerization of an acryloni-
; trile in an aqueous medium.
~ In contast to the elastomers described in U. S. Patent
No. 4,230,826, the elastomers of this invention have the advan-
tage that they exhibit substantially better adhesion to synthetic
substrates upon which they are formed than the elastomers known
heretofore. Furthermore, the degree of adhesion of these
elastomers is not dependent on the type of hydrolyzable groups
present in the room temperature vulcanizable composition.
~herefore, it is an object of the present invention to
provide organopolysiloxane compositions which exhibit improved
adhesion properties. Another object of this invention is to
provide room temperature vulcanizable compositions which will
adhere to synthetic substrates. Still another object of the
1l~'7~ 3~
--2--
-- present in~ention is to provide organopolysiloxane compositionshaving non-slump properties. A further object of this invention
is to provide elastomers whose degree of adhesion is not depen-
der~t on the hydrolyzable groups present in the composition.
Summary of the Invention
The foregoing objects and others which will become
apparent from the following description are accomplished in
accordance with this invention, generally speaking, by providing
compositions containing a diorganopolysiloxane having terminal
condensable groups, an organosilicon compound having at least
three hydrolyzable groups per molecule which are bonded to
silicon and an alkylenediamine in which at least one nitrogen-
bonded hydrogen atom is substituted with a polyalkylene oxide.
Detailed Description of the Invention
The alkylenediamines having at least one nitrogen-
bonded hydrogen atom substituted with a polyalkylene oxide are
ccmmercially available and may be prepared for example by the
~l addition of ethylene oxide or propylene oxide or the addition of
!1 both ethylene oxide and propylene oxide to an alkylenediamine.
It is preferred that the polyalkylene oxide consist of ethylene
oxide and propylene oxide units.
When the polyalkylene oxide contains various alkylene
oxide units, then the units may be randomly distributed or in
the form of blocks.
~ ~5 It is preferred that the molecular weight of the poly-
alkylene oxides be on the order of from about 200 to about
10,000 per mol of alkylenediamine.
` The preferred alkylenediamine is ethylenediamine.
Other alkylene diamines which may be used are 1,2-diaminopropane,
1j3-diaminopropane, 1,3-diaminobutane, 1,5-diaminopentane or
hexamethylenediamine.
For each molecule of alkylenediamine, 1, 2, 3 or 4
;~ nitrogen-bonded hydrogen atoms may be substituted with a poly-
alkylene oxide. It is preferred that for each molecule of
alkylenediamine that four such hydrogen atoms be substituted
with a polyall;ylene oxide.
It is preferred that the alkylene diamine in which at
least one nitrogen-bonded hydrogen atom is substituted with
polyalkylene oxide be an alkylenediamine of the general formula
~L~7
--3--
[Ho(c3H6)y(c2H4)x]2N(cH2)2N[(c2H4)x( 3 6 y 2
where each x and y represent the same or different integers
having an average value of at least 5.
It is preferred that the compositions of this invention
contain the alkylenediamine, in which at least one nitrogen-
bonded hydrogen atom is substituted with polyalkylene oxide, in
an amount of from about 0.1 to 5 percent by weight, based on the
total weight of the composition.
The compositions of this invention can be prepared
from the same diorganopolysiloxane having terminal condensable
groups which have been or could have been used heretofore in the
preparation of compositions which can be stored under anhydrous
conditions, but when exposed to moisture, crosslink at rocm tem-
parature to form elastomers. These compositions contain a
diorganopolysiloxane having terminal condensable groups and a
silicon compound containing at least three silicon bonded hydro-
lyzable groups per molecule and an alkylenediamine in which at
! least one nitrogen-bonded hydrogen atom is substituted with a
; polyalkylene oxide. The diorganopolysiloxanes having terminal
condensable groups generally used in the manufacture of such
compositions and which are also preferred in the present inven-
tion, may be represented by the general formula
Ho(siR2o)x~siR2oH~
in which R represents the same or different monovalent hydrocar-
bon radicals or substituted monovalent hydrocarbon radicals andx' is an integer having a value of at least 10.
Although this is generally not shown in formulas of
this type, siloxane units other than the diorganosiloxane units
(SiR2)O may be present within or along the siloxane chain of the
3~ above formula. Examples of such other siloxane units which are
generally present only as impurities are those of the formulas
RSiO3/2, R3SiO1/2 and SiO4/2, where R is the same as above. It
is preferred that siloxane units other than the diorganosiloxane
units not exceed about 10 mole percent and, more preferably,
that they not exceed about 1 mole percent, per mole of the
diorganopolysiloxane having tenminal condensable groups.
~ he hydroxyl groups in the above formula may be
partially or totally substituted with condensable groups other
than Si-bonded hydroxyl groups. Examples of such other conden-
~7~5-4-
sable groups are especially alkoxy groups having from 1 to 5
carbon atoms and alkoxyalkyleneoxy groups having from 1 to 5
carbon atoms, such as the methoxyethyleneoxy radical. Other
groups which may be partially or totally substituted for the
condensable groups are hydrolyzable groups such as acyloxy
groups, amino groups, aminoxy groups, acylamino groups, oxime
groups and phosphate groups. When the condensable groups in the
diorganopolysiloxane are hydrolyzable groups, these hydrolyzable
groups need not be the same as the hydrolyzable groups which are
present on the silicon compound having at least three silicon-
bonded hydrolyzable groups, per molecule, which are generally
referred to as ~crosslinkersn.
Examples of hydrocarbon radicals represented by R are
alkyl radicals, such as the methyl, ethyl, n-propyl and the
isopropyl radical, as well as octadecyl radicals; alkenyl radi-
cals such as the vinyl and the allyl radical; cycloaliphatic
~¦ hydrocarbon radicals, such as the cyclopentyl and cyclohexyl
¦ radicals, as well as methylcyclohexyl and cyclohexenyl radicals;
aryl radicals such as the phenyl and xenyl radicals; aralkyl
radicals such as the benzyl, beta-phenylethyl and the beta-
phenylpropyl radicals; and alkaryl radicals such as the tolyl
i radicals.
Preferred substituted hydrocarbon radicals represented
by R are haloaryl radicals such as the chlorophenyl and bromo-
phenyl radicals; and the cyanoalkyl radicals, such as the beta-
cyanoethyl radical.
; It is preferred that at least 50 percent, and more
preferably at least 90 percent of the number of R radicals in
the above formulas, i.e., the SiC-bonded radicals in the diorgano-
polysiloxane having terminal condensable groups, be methyl radi-
cals.
It is possible to use mixtures consisting of various
;~ diorganopolysiloxanes having terminal condensable groups in
preparing the compositions of this invention.
The viscosity of the diorganopolysiloxane having
terminal condensable groups is preferably between 100 and 500,000
mPa.s at 25C.
In preparing the compositions of this invention, it is
possible to use as silicon compounds containing at least three
.
5--5--
silicon-bonded hydrolyzable groups per molecule, any silicon
compounds of this type which could heretofore be used for the
preparation of compositions which can be stored under anhydrouc~
conditions, but when exposed to water at room temperature, cross-
link to form elastomers by mixing at least one such siliconcompound with a diorganopolysiloxane containing tenminal conden-
sable groups.
Examples of silicon compounds having at least three
silicon-bonded hydrolyzable groups per molecule which can be
used in preparing the compositions of this invention, are silanes
having the general formula
RaSiZ4 a'
where R is the same as above, Z represents a hydrolyzable group
and a is 0 or 1, and partial hydrolysates of these silanes
containing from 2 to 15 silicon atoms per molecule.
Examples of hydrolyzable groups represented by Z are
acyloxy groups (-OOCR'), hydrocarbonoxy groups and substituted
' hydrocarbonoxy groups ~OR'), hydrocarbonoxy-hydrocarbonoxy
groups (-ORnOR'), where R" is a bivalent hydrocarbon radical,
for example the -(CH2)2 radical, aminoxy groups (-ONR'2), amino
groups (-NR'2), acylamino groups (-NR'COR'), oxime groups
(-ON=CR'2) and phosphate groups ~-OOP(OR')2]. In these formulas
R' represents the same or different h~drocarbon radicals and
substituted hydrocarbon radicals. In at least some of the
previously cited formulas, at least one R' may represent hydro-
~ gen. The examples of hydrocarbon radicals represented by R are
equally applicable to hydrocar~on radicals represented by R' and
the examples of substituted hydrocarbon radicals represented by
R are e~ually applicable to substituted hydrocarbon radicals
represented by R'.
Examples of acyloxy groups are especially those having
from 1 to 18 carbon atoms, such as formyloxy, acetoxy, propion-
loxy, valeroyloxy, 2-ethylhexoyloxy, myristyloxy and stearoyloxy
groups. The acetoxy groups are the preferred acyloxy radicals.
Examples of hydrocarbonoxy groups are especially
/ alkoxy groups having from 1 to 10 carbon atoms, such as the
methoxy, ethoxy, n-propoxy, isopropoxy, butoxy, hexyloxy, heptyl-
oxy and octyloxy groups, as well as other hydrocarbonoxy groups
having from 2 to 10 carbon atoms, such as vinyloxy, allyloxy,
69~X
ethylallyloxy, isopropenyloxy, butadienyloxy and phenoxy groups.
An example of a hydrocarbonoxy-hydrocarbonoxy group is
the methoxyethylenoxy group.
Examples of aminoxy groups are dimethylaminoxy, di-
ethylaminoxy, dibutylaminoxy, dioctylaminoxy, dicyclohexyl-
aminoxy, diphenylaminoxy, ethylmethylaminoxy and methylphenyl-
aminoxy groups.
Examples of amino groups are n-butylamino, sec-butyl-
amino and cyclohexylamino groups.
An example of an acylamino group is the benzoylmethyl-
- amino group.
Examples of oxime groups are acetaldoxime, aceto-
phenoxime, acetonoxime, benzophenonoxime, 2-butanonoxime, di-
isopropylketoxime and chlorocyclohexanonoxime groups.
Examples of phosphate groups are dimethylphosphate,
diethylphosphate, di-n-butylphosphate, dioctylphosphate, methyl-
i ethylphosphate, methylphenylphosphate and diphenylphosphate
groups.
~3 The silicon compound containing at least three hydroly-
zable groups per molecule that are bonded to silicon, is pre-
ferably used in an amount of from about 0.5 to 15 percent by
weight, based on the weight of the diorganopolysiloxane having
tenminal condensable groups.
In addition to the diorganopolysiloxane having terminal
condensable groups, the silicon compound containing at least
~I three hydrolyzable groups per molecule that are bonded to silicon
and the alkylenediamine in which at least one nitrogen-bonded
hydrogen atom is substituted with a polyalkylene oxide, the
compositions of this invention may also contain any other sub-
stances which have been or could have been used heretofore in
preparing compositions which can be stored under anhydrous
conditions, but when exposed to moisture at room temperature,
crosslink to form elastomers containing a diorganopolysiloxane
having terminal condensable groups and a silicon compound having
at least three silicon-bonded hydrolyzable groups per molecule.
Examples of other substances which may also be added
to the GOmpOsitiOnS of this invention are organic fillers having
a surface area of at least 20 m~/g, inorganic fillers having a
sueface area of less than 20 m2/g, pigments, soluble dyes,
~:~7~ 5
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fragrances, organopolysiloxane resins including those containing
(CH3)3Siol/2 and SiO4/2 units, pure organic resins such as
polyvinyl chloride powder or powders of homopolymers or copolymers
of acrylonitrile, ethylene, vinyl acetate or styrene. These
pure organic resins may be prepared in the presence of a dior-
ganopolysiloxane having terminal condensable groups. Other
additives which may be included in the compositions are corrosion
inhibitors, oxidation inhibitors, bactericides, fungicides,
heat stabilizers, solvents, compounds to improve elastomeric
adhesion on substrates on which they are applied, such as gamma-
glycidoxypropyItriethoxysilane, condensation catalysts such
as tin salts or organotin salts of carboxylic acids, for example
dibutyltin dilaurate; emollients such as dimethylpolysiloxanes
which are end-blocked by trimethylsiloxy groups and which are
liquid at room temperature, or phosphoric acid esters or mixtures
of the aforementioned emollients, photo-protective agents and
' cell-generating agents such as azodicarbonamide.
; Examples of inorganic fillers having a surface area of
at least 20 m2/g are pyrogenically produced silicon dioxides,
silicic acid hydroxides which have been dehydrated while main-
taining their structure, and metal oxides, such as titanium
dioxide, ferric oxide, aluminum oxide and zinc oxide, provided
i that they have an area weight of at least 20 m2/g. (The area
weight factors indicated for fillers within this specification
are BET values, i.e., values that have been determined on the
basis of nitrogen absorption in accordance with ~STM Special
Technical Publication, No. 51, 1941, page 95).
Examples of fillers having an area of less than 20
m /g are quartz meal, diatomaceous earth, Neuberg Chalk, calcium
silicate, zirconium silicate, calcium carbonate, for example in
the form of ground chalk, calcined aluminum silicate and pow-
dered sodium aluminum silicate having molecular sieve properties.
Fibrous fillers such as asbestos or glass fibers or
mixtures of the aforementioned fibers, especially those having
an average length no greater than about 0.5 mm, or organic
fibers, or mixtures of organic fibers and inorganic fibers may
be used as well.
At least a part of or all of the above-mentioned
inorganic fillers may be treate~ with hydrophobic agents to
--8--
impart hydrophobic properties thereto. For example, the inor-
ganic fillers may be treated wi~h dimethylchlorosilane or tri-
methylethoxysilane or with stearic acid or with a mixture of two
or more of such hydrophobic agents. If desired, these fillers
may be treated with a hydrophobic agent in, for example, a ball
mill.
In preparing the compositions of this invention, it is
possible to use mixtures consisting of various fillers having an
area of at least 20 m /g or fillers with an area of less than 20
- 10 m /g, or mixtures containing at least one filler with an area of
at least 20 m2/g and at least one filler with an area of less
than 20 m2/g.
The compositions of this invention may be prepared by
mixing the constituents in any sequence. It is preferred that
the mixing take place at room temperature and under anhydrous
conditions. If desired, the mixing process may, however, also
take place at temperatures higher than room temperature, for
example at a temperature of from 35 to 150C.
The moisture in the air is generally sufficient to
crosslink the compositions of this invention. When desired,
crosslinking may also take place at temperatures higher or lower
than room temperature, for example, at between -5C to +10C.
i Crosslinking may also be carried out at water concentrations
which exceed the normal moisture content of the air, for example
in aqueous steam.
The compositions of this invention may be used to seal
horizontal, inclined or vertical fissures and similar cavities
having widths of, for example, 10 mm up to 50 mm. They may be
used to seal fissures or cavities in buildings, land vehicles,
aircraft or boats. Also, the compositions of this invention may
be used as adhesives especially for pure organic plastic sub-
stances such as polyvinylchloride, polyamides or epoxy resins,
as well as for wood and for the coating of a great variety of
substrates, including woven and nonwoven fabrics. They may also
be used in manufacturing molded objects, including electrical
insulations and for puttying windows.
In the following examples all parts are by weight,
unless otherwise specified.
- 9 -
Example I
About 65 parts of a dimethylpolysiloxane containin~ an
Si-bonded hydroxyl group in each of its terminal units and
having a viscosity of 80,000 mPa~s at 25C, are mixed in a
planetary mixer at room temperature and at 10 mbar (absolute)
with 23 parts of a trimethylsiloxy end-blocked dimethylpoly-
siloxane which has a viscosity of 100 mPa.s at 25C, and 6 parts
of methyltriacetoxysilane, 8 parts of pyrogenically produced
silicon dioxide, and 1 part of ethylenediamine in which at least
one nitrogen-bonded hydrosen atom is substituted with a poly-
alkylene oxide,,and which was prepared by the addition to the
ethylenediamine of 20 moles of ethylene oxide and 20 moles of
propylene oxide per mole of ethylene diamine. The composition
- obtained exhibited non-slump properties, i.e., the composition
did not flow out of vertical or inclined fissures prior to
crosslinking. The composition could be stored under anhydrous
' j conditions and when exposed to aqueous steam in atmospheric air,
j formed an elastomer.
omparison Example a)
' ', 20 The process descrtbed in Example 1 was repeated,
except that substituted and unsubstituted ethylenediamine was
omitted.
~, Example 2
A planetary mixer is used to mix at room temperature
and at 10 mbar (absolute), 58 parts of a dimethylpolysiloxane
; which has an Si-bonded hydroxyl group in each of its terminal
units and a viscosity of 80,000 mPa.s at 25C, with 27 parts of
a trimethylsiloxy end-blocked polysiloxane which has a viscosity
of 100 mPa.s at 25C, 9.5 parts of pyrogenically produced
silicon dioxide, 4.5 parts methyltris-(cyclohexylamino)-silane
and 1 part of ethylenediamine in which at least one nitrogen-
bonded hydro~en atom has been substituted with a polyalkylene
oxide and which was prepared by the addition to the ethylene-
di2mine of 20 moles of ethylene oxide and 20 moles of propylene
oxide per mole of ethylenediamine. The composition obtained
exhibited non-slump properties and could be stored under anhy
drous conditions and when exposed to aqueous steam in atmos-
pheric air, formed an elastomer.
9~5
--10--
- Comparison Example b)
The process described in Example 2 was repeated,
except that substituted and unsubstituted ethylenediamine was
omitted.
Example 3
The process described in Example 2 was repeated,
except that 4. 5 parts of methyltris-(2-butanonoxime)-silane
were substituted for the 4.5 parts of methyltris-(cyclohexyl-
amino)-silane. The composition obtained exhibited non-slump
properties and could be stored under anhydrous conditions and
when exposed to aqueous steam in atmospheric air, formed an
elastomer.
Comparison Example c)
The process described in Example 3 was repeated,
except that substituted and unsubstituted ethylenediamine was
omitted.
Strands of compositions prepared in accordance with
the Examples and the Comparison Examples were placed on panels
made of the materials listed in the following table and exposed
to atmospheric moisture. The strands cured to form elastomers.
, The thus-treated panels were then stored under water at room
temperature for 3 weeks. The following table shows the results
, obtained when the elastomers were removed from their respective
substrates.
.. ..
--1 1-- ,,
TABLE
Elastomeric strand obtained from compositions
Ex- Compari- Ex- Compari- Ex- Compari-
Panel ample son Ex- ample son Ex- ample son Ex-
/5 material(1) ample (a) (2) ample (b) (3~ ample (c)
Polyvinyl K A K A K A
Polymeth- X A K A K AK
acrylate
Epoxy resin K AK K A K AK
Melamine K A K A R A
resin
10 Polyurethane K A K A K A
Sipo* wood** K A R A K A
Sipo* wood*** K A R A K AX
Polyamide K A K A K R
Definitions:
A = Adhesion tear (separation between strand of elastomer and
the panel).
X = Cohesion tear (tear in elastomer strand).
AK = Adhesion and cohesion tear.
* Hard, durable, reddish-brown, bluish-purple wood of Entran-
drophragma utile.
** Coated with commercial white alkyd resin lacquer.
*** Coated with commercial "Xyladecor" [registered trademark]wood protection agent which simultaneously serves as a
I colorless varnish.
:
, , ~
