JPS6010057B2 - organosiloxane gel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Silicone gels are well known in the art and are described by Nelson
No. 3,020,260 and Spence, US Pat. No. 3,308,491.

Currently available silicone gel compositions are extremely useful as electrical capsule dressings and orthopedic gel pads used to prevent pressure sores.

The gel required is one that can be cured in 10 seconds on the electronic capsule coating line and has a pot life of at least one hour for use in the production of orthopedic gel pads. Filling some orthopedic pads with the gel, then storing the unused gel overnight and using the unused gel the next morning to fill additional pads will not cause problems with the material hardening during storage. Tokukan Sho 48-17847 discloses organosiloxane gels with improved properties over conventional gels. Although it has been found to be more than adequate for the applications associated with the manufacture of the products concerned, it also removes the undesirable characteristic odor of these gels and prevents the discoloration and fading caused by harsh heat treatments such as steam heat sterilization treatments. It is desired to do so.

The present invention is based on the discovery that vinyl chain-terminated polysiloxanes, which optionally contain vinyl groups in the chain, provide very fast cure times necessary for mass production of encapsulated electronic components.

By changing only the hydrogen-containing component of the gel and using the same vinyl-containing polymer, the cure time and pot life can be varied greatly. An additional element of the invention is the use of plastic or glass microballoons as fillers.

The microballoon is preferably made of glass, urea formaldehyde, phenolic resin or other plastic,
It can also be made from fly ash, which reduces the density of the gel pad. Gel pads that do not contain low density fillers, such as microballoons, have a specific gravity of approximately 1. With micro-balloon filler, the specific gravity is at least 1/3
can be easily reduced. This makes it easier to use the pad when used on hospital beds, hotel beds, etc.
I can handle it. This also reduces the weight of the aviation capsule electronics. Another object of the present invention is to provide an improved organosiloxane gel that is substantially odorless and free from undesirable discoloration and fading.

It is a further object of the present invention to provide improved organosiloxane gels that are particularly well suited for medical-healthcare applications where organosiloxane gels are subjected to severe sterilization treatments.

Another object of the present invention is to provide an organosiloxane gel that has a long curing time and pot life.

The organosiloxane gel of the present invention is the reaction product of the following mixture, which mixture has a viscosity of {1) 10 to 10,000 centistokes at 2500 and is mainly of the formula R2VISi○o. 5, R2Si○, RViSi○
and MeR2Si○o. 5 units in which each R is individually selected from the group consisting of methyl and phenyl, Vi represents a vinyl group and Me represents a methyl group, and At least 0.174 mol % of the units of R2VISi○o. 5 units and RV
An organosiloxane selected from the group consisting of iSi○ units, ■ average general formula XRMeSi○(R2Sj○)n
(RHSi○)mSjMeRX, where each R is as defined above, Me is a methyl group, and ×
is selected from the group consisting of days and R, and [1} and {
a liquid hydrogen siloxane in which up to 25 mole percent of the total R groups present in the siloxane are phenyl groups and n and m have average values such that the siloxane viscosity is 260 and does not exceed 10,000 centistokes; (3''
a platinum or platinum compound catalyst in an amount sufficient to provide at least 0.1 leg of platinum based on the combined weight of the siloxanes '1' and '2}, where '1} and '2}
Before the reaction, there are on average 1.4 to 1.8 gram atoms of silicon-bonded hydrogen atoms in {1} per gram molecular weight of {1}, and for each silicon-bonded hydrogen atom in (2},
} has such a property that at least one vinylsiloxy unit is present in '1}, and the molecular weight of '1} is according to formula 1.
0gvlsc. = 1.00 ten 0.0123M0.5, "M in the formula is the molecular weight and visc. is {1}
It is the viscosity in centistokes at 2500.

The organosiloxane copolymers defined above as component [1} are well known materials.

These substances include, for example, the corresponding halosilanes.
It can be prepared by hydrolyzing and condensing 2VISiC1, RViSiC12, R2SIC12 and CH3R2SICI together or by copolymerizing and equilibrating the corresponding siloxanes. Thus, for example, the formula (RViSi○)
4. Mix (R2Si○)4 and (ViR2Si)20 siloxanes in an appropriate ratio and add Na until equilibrium is established.
15 in the presence of a catalyst such as OH, KOH or LiOH
0-16030, then the copolymer was heated to 3P0
Prepared by neutralizing with 4. Preferably, the copolymers used in the present invention are substantially free of silicon-bonded hydroxyl groups. The R groups in the copolymer defined above may be the same group or different groups within each polymer unit or molecule.

However, ``as long as the requirements for viscosity and vinyl content are met and the phenyl content does not exceed 25 mole percent,
MeViSi○, PhViSi○,
Me2Si○, Ph2Si○, Me2VISi
○o. 5 "Ph2VISi○o.5 and PhMeSi
The units of ○ can be included in any combination. Throughout this specification, the symbols Me, Ph and Vi refer to methyl, phenyl and vinyl groups, respectively. copolymer m
should have a viscosity of 10 to 10,000 centistokes at 25:00. Of course, this is due to the presence of terminally closed ViR2Si○o. Controlled by an amount of 5 units. Preferably, the copolymer is essentially free of volatile low molecular weight materials.

However, as is well known, a substance with a particular viscosity is itself composed of many types of molecules having different molecular weights, and what is important here is the viscosity of the mixture of the types. A viscosity of about 200 to 1000 centistokes is preferred. The hydrogen siloxane (■) used in the present invention has an average general formula: XRCH3Si○(R2Si○)n(RHSi○
) mSiMeRX (in the above formula, each R is a methyl group or a phenyl group, X is R or day, and n is a viscosity of 25 ° C.
is 0 or any positive integer or fraction as long as the viscosity does not exceed 10,000 centistokes, and m is the viscosity of 25
0 or any positive integer or fraction as long as it does not exceed 10,000 centistokes;
The sum of +n can vary from 0 to 1000,
Of course, the upper limit varies depending on the types of R groups and x groups present).

Most preferred are viscosities within the range of 1 to 2000 centistokes.

The R groups in a given molecule or a given mixture of molecule types falling within this definition may be the same or different groups. Thus, the terminal closure units are HMe2Si○ cape units and/or HMePhSi○o. 5 units and/or Me3Si
○o. It can be 5.

If a repeating unit exists, it is Me2Si○, M
It may be an ePhSi○, Ph2Si○, MeHSi○ unit, or any combination of these terminal closing units and repeating units may be used. However, when phenyl groups are present in component '1) or '2) as defined in the present invention, the total number of such phenyl groups is equal to component {1}
There should be no more than 25 mole percent of the total R groups present on the decapod, with a preferred maximum of about 10 mole percent. The hydrogen siloxanes defined above are well-known compounds, which can be used, for example, as the "corresponding chlorosilanes", i.e. MeRSiH
C1, MeSjHC12, RMe2SIC1, RSiH
C12, and R2SIC12 by co-hydrolysis and co-condensation or siloxane (MeRHSi)20, (RM
e2Si)20 "(R2Si○)4 and (RHSj○)
It can be produced by equilibration with an acid catalyst in step 4. Preparation of the gel of the present invention requires control of the proportions of siloxanes '1} and '2- used. The ratio is calculated by calculating the molecular weight of siloxane [1} using the equation logvisc. (2500
centistokes) = 1.00 ten 0.0123
When calculated by 0.5 of siloxane '1), the number of siloxane {small silicon bonded atoms per molecule of siloxane '1) is on average 1.4 to 1.8 (preferably 1.45
~1.7) Siloxane per atom each day {
1) has at least one vinyl-substituted siloxy unit.

Although the amount of SiH' present in the siloxane {2} is preferably determined by analytical methods known for such measurements, it can also be calculated from the viscosity of the siloxane {2}. It can be seen that the weight ratios of 1} and '2) are subject to extremely wide variations since they are completely dependent on the molecular weight on the one hand and the SiH content on the other hand. Although the formula gives a "number average" molecular weight, this has been shown to be true for linear methylpolysiloxane fluids with molecular weights greater than 2500, as shown by A.J.
J. Bany) [Journal/
Of applied. Jumalof
Applied Physics), Volume 17, 1020
~102 December 1946]. Of course, this expression may not be strictly accurate, especially when phenyl groups or relatively large amounts of vinyl groups are present. Nevertheless, molecular weight calculations in this manner, used in conjunction with the limitations defined above, indicate the proportions of components {1} and {2} required to obtain the desired result.

To facilitate processability in obtaining suitable concentration levels of components [1) and {2), it is sometimes advantageous to use small amounts of diluent copolymers in conjunction with component {2). .

Suitable diluent copolymers include, for example, MeSi○ and VIMe.
2Sj○o. 5 units “or Me2Si○, MeViS
i○ and Me3Si○ unit, or Me2Sj○, VIM
e2Si○o. 5. MeViSj○ and Me3Si○o
．． It can consist of 5 units. The gel of the present invention is formed when a defined proportion of components '1} and (2) are intimately mixed with a catalyst, preferably a platinum compound catalyst, and allowed to react. Many types of platinum compound catalysts for SiH-olefin addition reactions are well known, but the preferred type, especially when visual transparency is required, are those platinum compound catalysts that are soluble in the reaction mixture. The platinum compound is disclosed in U.S. Patent No. 3159601 by Mr. Ashby (HBY).
It can be selected from those having the formula (PtC12/olefin) 2 and (PtC13/olefin) as described in No. The olefins shown in the above two formulas can be almost any type of olefin, but from 2 to
Preference is given to alkenes with 8 carbon atoms, cycloalkenes with 5 to 7 carbon atoms or styrene. Specific olefins that can be used in the above formula are ~ethylene, propylene, various isomers of butylene,
These include octylene, cyclobentene, cyclohexene, and cycloheptene. Yet another platinum-containing material that can be used in the compositions of the present invention is platinum chloride cyclopropane rust (P to 12 C3 melon) 2 as described in U.S. Pat. No. 3,159,662 to Ashby. Still other platinum-containing materials are described in U.S. Pat. No. 3,220,972 by Lamoreaux*
The fin body may be formed from chloroplatinic acid and a substance selected from the group consisting of alcohols, ethers, aldehydes and mixtures thereof, up to 2 moles per platen of platinum, as described in the above.

A preferred platinum compound for the purposes of the present invention is Karst
edt French Patent 1548775 and US Patent 3715
334, 3775452 and 3814730.

As already mentioned, this type of platinum ring is formed by reacting platinum halide with a vinyl-containing organosilicon material, such as tetramethyltetravinylcyclotetrasiloxane, in the presence of a base and an organic solvent. More specifically, these Karstedt
) type platinum-vinylorganosiloxane catalyst is available from Kars
As defined by tedt, it contains virtually no chemically bonded halogen, and ■ platinum halide and song 'a.
} and a vinyl-containing organosilicon material selected from vinylsiloxanes consisting primarily of chemical bonding units of the formula {b}.

Here, R is selected from a monovalent hydrocarbon group and a monovalent halogenated hydrocarbon group, X is a hydrolyzable group, and a is 0 to
An integer with a value of 2, b is an integer with a value of 1 to 4, a and b
The sum is 1 to 4, c is an integer of 1 to 3, d is an integer of 0 to 2,
e is an integer from 0 to 3; x is an integer from 1 to 100; y is an integer from 0 to 3;
198 is an integer, and the sum of x and y is 1-199. The sum of x and y is preferably 1-30. Formula {1)
The R groups in (1) and (2) include, for example, alkyl groups such as methyl, ethyl, propyl, butyl, bentyl, hexyl, heptyl, octyl, etc., alkenyl groups such as vinyl, allyl,
1-butenyl, etc., cycloalkyl groups such as cyclohexyl, cycloheptyl, etc., aryl groups such as phenyl, methyl, tolyl, xylyl, etc., aralkyl groups such as penzyl, phenylethyl, phenylpropyl, etc., halides of groups of the above-mentioned types, such as chloromethyl, Includes chloropropyl, chlorophenyl, dipromophenyl, etc.

In the above formula, when R represents more than one group,
All of these groups may be the same group or a combination of any two or more of the R groups mentioned above. Unsaturated silanes included in formula m include, for example, tetravinylsilane, divinylallylmethylsilane, divinylmethylsilane, trivinylphenylsilane, divinylmethylchlorosilane, trivinylchlorosilane, divinylmethylethoxysilane, divinylmethylacetoxysilane. etc.

Encompassed by the formula ■ are vinyldisiloxanes of the formula such as 103-divinyltetramethyldisiloxane, hexavinyldisiloxane, sMm
n-divinyltetraphenyldisiloxane "1, 1, 3-
These include trivinyltrimethyldisiloxane, SMm-tetravinyldimethyldisiloxane, and the like.

Encompassed by vinyl siloxane of formula ■,
Vinylcyclopolysiloxanes such as 1,3,5-trivinyl-10315-trimethylcyclotrisiloxane, 103,507-tetravinyl-113,517-tetramethylcyclotetrasiloxane, 1,3-divinyl-octaphenylcyclobentasiloxane, etc. .

Platinum halides that can be used in the practice of this invention include, for example, PtC16, Pt20, and metal salts such as NaHPt.
C16・nH20, KHPtC16・nH
20, Na2PtC16・nH20, K2PtC16
・There is nH20.

Also, PtC14・elbow 20 and primary platinum type halide such as P 12, NaPtC14・mH20, day 2PtC
14・mH20, NaHPtC141mH20, KHP
There are tC14・mH20 and K2PtBr4. After combining the platinum halide and the unsaturated organosilicon material, the platinum-siloxaso complex can be formed by various means, the choice of which method may vary depending on the nature of the platinum halide and the unsaturated organosilicon material used. .

For example, temperatures of 150 o'clock to 200 o'clock may be used, but temperatures of 0 to 1000 o'clock are preferred.

When the platinum halide is in the form of a platinum-olefin ring, the reaction occurs immediately even when heat is applied from the outside. In some cases, external cooling may be necessary. To remove chemically bonded halogens, there must be an amount of water in the mixture that is at least equal to the number of grams of platinum multiplied by its valence, expressed in moles. It has been proposed by Kadai Tedt that it is advantageous to ensure that

Excessive amounts of water should be avoided to avoid decomposing the platinum-vinylsiloxane after it is formed and impairing its activity. Experience has shown, however, that in all cases, unless water is specifically excluded, more than a minimum amount of water will generally be present in the mixture due to atmospheric moisture; has been shown to chemically bond or associate with the reactants and solvents used during platinum-vinylsiloxane preparation. One method that has been found to be effective in removing chemically bound halogens from the reaction mixture is heat and vacuum, e.g.
It is a technique in which stripping is performed multiple times in moist air using three or more side pressures, and inert gas can also be used instead of vacuum.

Another method that has been shown to be effective in removing chemically bound halogens is the use of bases, which neutralize any halogen acids that may be present in the mixture. Suitable bases include, for example, alkali carbonates such as sodium carbonate, potassium carbonate, sodium bicarbonate, alkali carbonates and bicarbonates, alkali hydroxides such as sodium hydroxide, potassium hydroxide, and the like. Effective results are obtained by using a slight excess of base over that required to neutralize all of the chemically bound halogen and form the corresponding salt. At least enough base should be used to remove substantially all of the chemically bound halogen. When utilizing vinyl-containing organosilicon materials containing silicon-bonded halogens, additional bases such as alkali bicarbonates should be used. In addition to stripping and base treatment, other methods can be used to remove chemically bound halogens from mixtures of vinyl-containing organosilicon materials and platinum halides. For example, absorbents such as molecular sheep can be used. Mesh size 30~1
Suitable commercially available molecular sieves having a diameter of at least 20 mm are available. Stannous chloride, SnC12.20, can be used to remove chemically bound halogens from organic solvent-resistant platinum halides, such as K2PtC14.

Platinum-pinylsiloxanes can be prepared in aqueous media as long as they are readily available. The platinum-vinylsiloxane can be recovered using a non-frustrating organic solvent, leaving excess chemically bound halogen in the aqueous soot. It has been found advantageous to use an organic solvent to promote contact between the platinum halide and the vinyl-containing organosilicon material during initial bright mixing.

In some cases, mixtures of organic solvents and water can be used.
The nature of the solvent may vary depending on the type of platinum halide used as well as the nature of the vinyl-containing organosilicon material. However, in general, hydrocarbon solvents such as aromatic hydrocarbons, alcohols such as ethyl alcohol as well as other low molecular weight aliphatic alcohols, ethers, etc. are available. What is surprising here is that the organic solvent used in the preparation of the platinum complex catalyst was added to the above-mentioned organosiloxane and liquid hydrogen siloxane, respectively, after the catalyst was prepared. It has been found that removal from this catalyst prior to contacting provides an organosiloxane gel that is odorless and that does not discolor or fade when exposed to severe heat treatments such as steam sterilization.

Using this solvent-free catalyst, organosiloxane gels with extended curing times and pot lives can also be obtained.
Removal of the organic solvent may be accomplished by any convenient method known in the art.

A preferred method consists of simply stripping the reaction mixture at elevated temperature under reduced pressure. The exact conditions, ie, reduced pressure and elevated temperature, will vary depending on the particular solvent removed. These conditions are within the range that can be determined by a person of ordinary skill in the art. One of the most preferred catalysts contemplated within the scope of the invention is a combination of chloroplatinic acid containing four molecules of water of hydration and tetramethyltetravinylcyclotetrasiloxane in a base such as sodium bicarbonate as well as an organic solvent such as ethanol. is a platinum-vinylorganosiloxane formed by reacting in the presence of and removing the organic solvent, such as methanol.

As is known in the art, the SiH-olefino addition reaction linking components m and {21 can occur at room temperature;
Accelerated at higher temperatures.

When using the catalysts described in the Kastedt French and US patents (even when subsequently removing the solvent as discussed above), the catalyst concentration level is 0 at the platinum concentration present in the mixture. Concentrations as low as .1 breast may be reached. When speeding up curing is desired, such as in high-speed encapsulation of electronic components, the platinum level is increased by up to about 2 kalpas. The level of concentration of catalyst used in various situations is, of course, dependent on the desired pot life and flow completion or cure time, and is of a nature that can normally be determined by one skilled in the art. The compositions of the present invention can also be modified by incorporating various bulking agents or fillers. Examples of the many fillers that can be used include titanium dioxide, lithopone, zinc oxide, zirconium silicate, silica gel, iron oxide, diatomite, calcium carbonate, fumed
ed) Silica, silazane-treated silica, precipitated silica, glass fiber, magnesium oxide, chromium oxide, zirconium oxide, aluminum oxide, alpha quartz, clay, asbestos, carbon, graphite, cork, cotton, synthetic fiber, etc. of the present invention. Preferred fillers that can be used in practice are microspheres or microballoon type fillers.

These fillers are characterized by their extremely small size and consist of gas-filled glass or plastic spheres. Finely ground fly ash with closed pores can also be used. These microsphere fillers have a diameter of approximately 20~
It is preferably used in an amount of about 1 to about 25 parts, preferably 14 parts per 10 parts of siloxane '1' and '21. When using low viscosity polysiloxane mixtures, it is increasingly necessary to add some filler in addition to the microsphere filler to increase the viscosity to such an extent that the microsphere filler does not separate from the polysiloxane before curing. Ru.

Therefore, when the viscosity of the polysiloxane mixture of (1} and The polysiloxane is viscosityized to such an extent that it does not separate from the mixture.The application of the gel of the present invention is not difficult and can be accomplished by those skilled in the art.For example, for breast implants, silicone rubber hoses can be coated with a gelling composition. orthopedic bed pads are produced by curing a gelling composition and covering it with an elastomeric cover. Frictional losses are reduced by coating the inside of the pipe with a gelling composition and curing the composition.

Friction on a ship passing through water is reduced by coating the ship's hull with a gelling composition and curing it. The same curing technique can be used to fill tubes containing electrical conductors with gelling compositions. The same technology can be used to manufacture crash pads for vehicle interiors, to manufacture cushioning bumpers for vehicle interiors, and to line hard hats. Lightweight mattresses and pads are manufactured using gelling compositions filled with microballoons. The following examples are presented to illustrate the best mode of carrying out the invention. Example 125q
has a viscosity of 2000 centipoise at 0 and 9
9.17 mol% Me2SiO units, 0.82 mol% VIMe2Si○o. 5 units, 0.006 mol% Me
ViSi○ units and 0.004 mol% (Me)3Si
○.

．． Methyl vinyl polysiloxane consisting essentially of 5 units 1
A mixture containing 0.00 parts was prepared. To this, 98.3
mol % Me2Si○ units and 1.7 mol % VIMe
2Si0o. 8.2 parts of diluted copolymer containing 5 units and 81.0 mol% Me2Si○ units, 17.5 mol%
of MeHSi○ units and 1.5 mol% of Me2HSi○
o. 1.8 parts of hydrogen siloxane containing 5 units were mixed. The viscosity of the hydrogen siloxane material is 5 at 260
000 centipoise or less. To this composition was added the catalyst described in Example 1 of the Lamoreo patent in an amount sufficient to provide IQ cape platinum based on the weight of the vinyl-containing polysiloxane. The three components were thoroughly mixed and used to encapsulate electrical components on the assembly line.

The composition cured to a gel at 125 minutes with 1 stone sand. Example 2 This example is a single vinyl-containing policy.

It illustrates the versatility that can be achieved with xane. The 100 parts of vinyl-containing polysiloxane used in Example 2 was the same as that used in Example 1. The hydrogen-containing siloxane was different from that used in Example 1, and the product formed was used to produce a high tear strength gel-filled orthopedic mattress. The 2.8 parts of hydrogen-containing polysiloxane in this Example 2 was 77.2 parts.
mol% Mebj○ unit, 13.7 mol% MeHSj
O units and 9.1 mol% Me3Si○. ．． It contained 5 units and had a viscosity of 50 centipoise at 25°C. The catalyst used was the same and at the same concentration as used in Example 1. 7.2 parts of diluent contains 99.62 mol% Me2Si○ units, 0.12 mol% MeVjSi
It contained ○ units and 0.26 mol % Me3Si○ units.

The mixture of each component was stable, ie, it did not harden even when left at room temperature for 2 days.

When this was used to fill an elastic transparent mattress cover to form an orthopedic pad, it had satisfactory performance. The strength of this material was measured by casting 8 x 8 x lin pads, curing them at 125 oo for 60 minutes, and then placing a 6 inch long 121b cylindrical weight on top of the pads. The tear strength of the pad is sufficient to hold a person's weight if the pad does not burst under a weight placed on it for 72 hours. The gel pad of the present invention had sufficient strength to meet this requirement. Example 3 A lightweight orthopedic gel pad for use in the manufacture of mattresses was manufactured in the following manner.

That is, the 10 part pinyl-containing polysiloxane used in this Example 3 was the same as that used in Examples 1 and 2. The hydrogen-containing siloxane was the same as that used in Example 2, but only 2.1 parts were used. This example used the same diluent used in Example 2, but at 5.4 parts. The catalyst used was the same as in Example 2 and at the same concentration. mix 20
It was thickened with 2 parts of fumed silica having a surface area of 0 W/W, 14 parts of 50 micron microspheres were added, and the mixture was homogenized. When the mixture was cured as in Example 2, a relatively lightweight mattress was produced. The density of the microsphere-containing gel was 0.67 ta'. Example 4 MeSi0,0.8 with a viscosity of 2000 centipoise and 99.17 mol % at 25 qo
2 mol % of VMebu i○o. 5, 0.006 mol% MeViSi○ and 0.004 mol% (Me)
3Si○o. A mixture containing a methylvinylpolysiloxane 10 base consisting primarily of 5 was prepared.

This, Satoshi. 3 mol% Mebui○ units and 1.7 mol%
VIMe2Sj○o. Diluent polymer 9 containing 5 units
．． 0 parts and 81.0 mol% Me2SiO units, 17.
5 mol% MeHSi○ units and 1.5 mol% Me
2HSj0o. It was mixed with 1.0 part of hydrogen siloxane containing 5 units. The viscosity of hydrogen siloxane material is 5 at 250C.
000 centipoise. To this composition was added a platinum-vinylsiloxane catalyst (in an amount sufficient to provide IQ blood platinum based on the weight of the vinyl-containing polysiloxane). When preparing this catalyst, first prepare 1, 3, 5, 7
-Tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane74. and 4.5 parts by weight of sodium bicarbonate. Chloroplatinic acid containing 4 moles of water of hydration in this mixture 3. parts by weight and dry ethanol 17
．． Parts by weight of the mixture were slowly added at room temperature while stirring. It took about 5 minutes to add the chloroplatinic acid and ethanol mixture. Carbon dioxide gas evolved from the reaction mixture. This mixture is stirred until the generation of carbon dioxide gas has substantially ceased, at which point the reaction mixture is
5oo and maintained at this temperature for about 2 hours.

The reaction mixture was then stripped to remove ethanol using 100q0, approximately 2 liters of HQ. The generated ethanol-free platinum-vinylsiloxane complex (approximately 1
．． (containing 5-2.0% platinum) was cooled, filtered and washed with tetravinyltetramethylcyclotetrasiloxane. Thoroughly mix the above three ingredients 125q0
It was cured for 2 hours.

The resulting gel was odorless and did not change color or fade even after aging for 6 hours at 300-350°C. Even when the gel was steam sterilized, it did not change color or fade. The gel of Example 4 was used to fill an elastic transparent mattress cover to form an orthopedic pad, which was odorless and had good performance.

Furthermore, the gel of Example 4 was used to produce an artificial implantable breast. Example 5 Viscosity at 25qC is 500 centivoice and 98.4 mol% Mebj○, 0.94 mol% VI
Me2Si○o. 5, 0.52 mol% MeViSi○
and 0.15 mol% (Me)3Si○o. A mixture containing 100 parts of methylvinylpolysiloxane consisting essentially of 5 was prepared.

In addition, 98.3 mol% of Me2Si○ units and 1.7 mol% of VIMe2Si○o. 8.2 parts of a diluent copolymer containing 5 units and 81.0 mol% Me2Si○ units,
17.5 mol% MeHSi0 units, and 1.5 mol%
Hydrogen siloxane containing 0 units of Me2HSi 1.8
The parts were mixed. The viscosity of the hydrogen siloxane material is less than 5000 centipoise at 25:00. To this composition was added the catalyst described in Example 4 above in an amount sufficient to provide a platinum one-legged dish based on the weight of the vinyl-containing polysiloxane.
Example 4 After thoroughly mixing and curing these three components,
It was aged in the same manner as the gel, but there was no discoloration or fading. The resulting gel had no odor. Example 6 A lightweight orthopedic gel pad for use in the manufacture of mattresses was made as follows.

The 10 part vinyl-containing polysiloxane used in this Example 6 is the same as that used in Examples 4 and 5. However, 2.8 parts of hydrogen-containing siloxane is 77.2 mol%
of Me2Si○ units and 13.7 mol% of MeHSi○ units. The viscosity of this material was 50 centipoise at 25:00. The catalyst used was the same as in Example 4 and at the same concentration. 7.2 parts of diluent is 99.62 mol%
Me2Si○ units, 0.12 mol% MeVjSi○
unit and 0.26 mol% Me3Si○o. It contained 5 units.

This component mixture was stable, ie, did not harden after being left at room temperature for 2 days.

Claims (1)

[Claims] 1 Mainly (1) The viscosity at 25° C. is 10 to 10,000 centistokes and mainly the formula R_2ViSiO_0_. ＿
5. RViSiO, R_2SiO and MeR_2SiO
＿0＿． _5 (However, each R is strictly selected from the group consisting of methyl and phenyl groups, Vi represents a vinyl group, and Me
represents a methyl group, and at least 0.174 mol% of the units in the copolymer are R_2ViSiO_0_.
(selected from the group consisting of _5 units and RViSiO units)
organosiloxane, which is a copolymer consisting of units of
(2) The average general formula is XRMeSiO(R_2SiO
)n(RHSiO)mSiMeRX (however, each R and M
e is as defined above, X is selected from the group consisting of H and R, up to 25 mol% of all R groups present in the siloxanes of (1) and (2) are phenyl groups, and n and m are the viscosity of the hydrogen siloxane at 25°C of 10
(3) reacting a platinum halide with a vinyl-containing organosilicon material in the presence of an organic solvent; a platinum-vinylorganosiloxane catalyst in an amount sufficient to provide at least 0.1 ppm platinum based on the combined weight of the siloxanes (1) and (2), The properties of 1) and (2) are (1)
There are an average of 1.4 to 1.8 gram atoms of silicon-bonded hydrogen atoms in (2) per gram molecular weight of (2) and at least one vinylsiloxy unit in (1) for each silicon-bonded hydrogen atom in (2). It has the property of existing,
The molecular weight of (1) is calculated using the formula log visc. =1.0
0+0.0123M^0^. A curable organosiloxane composition, calculated by ^5, where M is the molecular weight and visc. is the viscosity of (1) in centistokes at 25°C. 2. The composition of claim 1, wherein R is methyl. 3. The composition according to claim 1, wherein the hydrogen siloxane has a viscosity of 1 to 2000 centistokes. 4. The composition of claim 1, wherein the platinum-vinylorganosiloxane complex is formed by reacting chloroplatinic acid and a vinyl-containing siloxane in the presence of a base and an organic solvent and then removing the solvent. 5. Claim 4, wherein the vinyl-containing siloxane is tetramethyltetravinylcyclotetrasiloxane.
Compositions as described in Section. 6. The composition of claim 4, wherein said chloroplatinic acid contains 4 moles of water of hydration and said vinyl-containing siloxane is tetramethyltetravinylcyclotetrasiloxane. 7. The composition of claim 4, wherein said chloroplatinic acid contains 4 moles of water of hydration, said vinyl-containing siloxane is tetramethyltetravinylsiloxane, and said organic solvent is ethanol. 8. Claims in which the chloroplatinic acid contains 4 moles of water of hydration, the vinyl-containing siloxane is tetramethyltetravinylcyclotetrasiloxane, the base is sodium bicarbonate, and the solvent is ethanol. Composition of Clause 4. 9. The composition of claim 8, wherein R is methyl. 10 Mainly (1) The viscosity at 25° C. is 10 to 10,000 centistokes and the formula R_2ViSiO_0_.
_5, RViSiO, R_2SiO and MeR_2Si
O_0_. _5 (provided that each R is individually selected from the group consisting of methyl and phenyl groups, Vi represents a vinyl group, and M
e represents a methyl group, and at least 0.174 mol% of the units in the copolymer are R_2ViSiO_0_.
(selected from the group consisting of _5 units and RViSiO units)
organosiloxane, which is a copolymer consisting of units of
(2) The average general formula is XRMeSiO(R_2SiO
)n(RHSiO)mSiMeRX (however, each R and M
e is as defined above, X is selected from the group consisting of H and R, up to 25 mol% of all R groups present in the siloxanes of (1) and (2) are phenyl groups, and n and m are the viscosity of the hydrogen siloxane at 25°C of 10
(3) reacting a platinum halide with a vinyl-containing organosilicon material in the presence of an organic solvent and then removing the organic solvent; and (4) a platinum-vinylorganosiloxane catalyst in an amount sufficient to provide at least 0.1 ppm platinum based on the combined weight of the siloxanes (1) and (2); ) per 100 parts of siloxane
It consists of four components of about 25 parts of gas-filled microspheres with a diameter of about 20 to 250 microns, and the properties of (1) and (2) above are on average 1.4 per gram molecular weight of (1) (2). There are ~1.8 gram atoms of silicon-bonded hydrogen atoms and for each silicon-bonded hydrogen atom in (2)
) is such that at least one vinyl siloxane unit is present, and the molecular weight of (1) is according to the formula lo
g visc. =1.00+0.0123M^0^. ^
5 (where M is the molecular weight and visc. is 25°C
The curable organosiloxane composition is calculated by (1) viscosity in centistokes. 11. The composition according to claim 10, further characterized by the presence of 0.5 to 5.0 parts of a non-cytoplasmic filler.