RU2377264C1 - Silicon composite material - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to biocompatible silicon composite materials. Proposed is silicon composite material for making a barrier shell based on a composition which vulcanises in the presence of polyorganohydridesiloxane and platinum catalyst, which contains polymer binder which is filled with reinforcing silica - polydimethylvinylsiloxane, which contains 0.12-0.07 wt % vinyl groups, or polydimethyldiphenylvinylsiloxane, which contains 0.086 wt % vinyl groups and not more than 5-8 mol % diphenylsiloxane links, or their mixture, and contains at least one or more organosilicon compounds, with phenylsilsesquioxane or branched structure, containing functional groups which are capable of chemically bonding with reactive groups of the polymer binder. The organosilicon compounds used are polyphenylsilsesquioxane-polydiorganosiloxane block-copolymers of general formula: {[C₆H₅SiO_1,5]_m[C₆H₅(OH)SiO]_n[R¹R²SiO]_p}, where R¹=R²=CH₃- or R¹=CH₃-, R²=CH₂-CH-; m=57.868-75.695, n=2.288-3.880, p=93-360 and/or MQ (MQD^vin) type resin organosilicon resin of general formula: {[(CH₃)₃SiO_1/2]_x[SiO₂]₁[(CH₃)₂SiO]_y[CH₃VinSiO]_z}, where x=0.9-1.2, y=0-0.4, z=0.1-0.4; or MQ (MQT^vin) type organosilicon resin of general formula: {[(CH₃)₃SiO_1/2]_x[SiO₂]₁[VinSiO_1,5]_y}, where x=0.9-1.2; y=0.1-0.4.

EFFECT: silicon composite material for making a barrier layer, suitable for use in cases where swelling of a layer under effect of liquid low-molecular siloxanes is undesirable.

5 cl, 1 tbl, 6 ex

Description

The present invention relates to biocompatible silicone composite materials suitable for the preparation of a barrier coating. Silicone composite materials are widely used in the field of biomedicine for the manufacture of internal sealed gel-filled prostheses, medical tubes for various purposes, as part of cosmetics.

Some types of implants consist of weakly crosslinked silicone gels encapsulated in silicone-filled silicone shells. The greatest danger of such implants is associated with the possibility of penetration of non-crosslinked low molecular weight components of the gel through the shell. A similar kind of migration of gel fragments leads to a change in the volume of the walls of the shell, that is, to its swelling. As a result, tensile strength and elongation at break are reduced in a long-swelling elastic material. Deterioration of the above properties may lead to rupture of the walls of the shell.

One of the known methods for solving this problem is to introduce an additional barrier layer into the implant shell. The barrier layer is introduced in order to minimize the penetration of non-crosslinked gel components through the shell, that is, to reduce the amount of swelling of the shell under the influence of weakly crosslinked silicone gel.

Silicone composites are known for preparing a barrier layer based on the reaction products of dimethylpolysiloxane and 3,3,3-trifluoropropylsiloxane, diphenylpolysiloxane or methylphenylpolysiloxane. The final products contain from 8 to 50 mol.% Diphenylsiloxane units, mainly from 15 to 30 mol.%, At least 90 mol.% Methyl 3,3,3-trifluoropropylsiloxane substituents, or at least 30 mol.% Methylphenylsiloxane substituents (patents US No. 4,472,226, IPC B29D 9/00, 1984; 4,889,744, IPC A01N 1/02, 1989; 5,007,929, IPC A61F 2/10, 1991). The barrier layers obtained on the basis of these composite materials effectively prevent the migration of weakly crosslinked silicone gels through the shell in the presence of from 15 to 30 mol.% Diphenylsiloxane units in the polydimethylsiloxane elastomer.

However, it should be noted that when the content of diphenylsiloxane units is up to 8-12 mol%, the amount of swelling of the barrier layer when exposed to a weakly crosslinked silicone gel increases sharply, and this is a disadvantage of the known inventions.

The literature describes the use in cosmetics and personal protective equipment manufactured by Shin-Etsu Silicones of new products of the KSP-100 series, · 101,105, 300, containing organosilicon resins having a silsesquioxane structure. KSP powders consist of silicone rubber spheres coated with silicone resin. The outer shell of a sphere based on siloxane rubber is chemically bonded to an organosilicon resin. KSPs containing organosilicon resins with methyl groups have been described to swell well in liquid silicones such as cyclomethicone and dimethicone. KSPs containing organosilicon resins with phenyl groups reduce swelling in low viscosity liquid dimethicones (Product Brochure, PDF Hybrid Silicone Powder for Personal Care, file format: PDF / Adobe Acrobat, Shin-Etsu 2000.11 / 2004.3).

The closest in technical essence and adopted by us as a prototype is a silicone composition for producing a barrier layer based on polydimethylvinyl diphenylsiloxane containing from 8 to 50 mol.% Diphenylsiloxane units, 0.133 mol.% Dimethylvinylsiloxane groups, filled from 15 to 70 wt.h. per 100 parts by weight a reinforcing silica polymer vulcanized using a polysiloxane containing an Si — H group and platinum containing a catalyst. As a silicone gel acting on the barrier layer, normally crosslinked dimethylpolysiloxane was used, consisting of 5-20 parts by weight, mainly 8 parts by weight, polysiloxane containing Si-H groups, and 80-95 parts by weight, mainly 92 parts by weight, oligodimethylvinylsiloxane with terminal trimethylsiloxy groups, the catalytic amount of platinum-containing catalyst was (5 to 50) · 10 ^-6 parts by weight (U.S. Patent 4,455,691, IPC A61F1 / 100, 1984).

The disadvantage of such a silicone composition is that when the content in polydimethylvinyl diphenylsiloxanes is less than 15 mol% of diphenylsiloxane units, the amount of vulcanizate swelling under the influence of silicone gel increases sharply (from -1.86% to + 2.33 ÷ + 11.22%).

The present invention is the development of a silicone composite material for the manufacture of a barrier layer suitable for use in cases where the swelling of the layer under the influence of liquid low molecular weight siloxanes is undesirable. The effect should be observed even when the content of diphenylsiloxane units in the elastomers is up to 12 mol%.

To solve this problem, a silicone composite material is proposed, characterized in that it includes polydimethylvinylsiloxane containing 0.12 ÷ 0.07 wt.% Vinyl groups filled with reinforcing silicon dioxide or polydimethylvinyl diphenylsiloxane containing 0.086 wt.% Vinyl groups and 5-8 mol.% diphenylsiloxane units, or mixtures thereof contains at least one or their mixture, an organosilicon compound having a phenylsilsesquioxoxane or branched structure containing functional groups capable of chemically bonding yvatsya with reactive groups of the polymeric binder.

As organosilicon compounds use:

- polyphenylsilsesquioxoxane-polydiorganosiloxane block copolymers of the general formula:

{[C ₆ H ₅ SiO _1,5 ] _m [C ₆ H ₅ (OH) SiO] _n [R ¹ R ² SiO] _p },

where R ¹ = R ² = CH ₃ -, R ¹ = CH ₃ -, R ² = CH ₂ -CH-,

m = 57.868 ÷ 75.695, n = 2.288 ÷ 3.880, p = 93 ÷ 360

or - an organosilicon resin of type MQ (MQD ^Vin ) of the general formula:

{[((CH ₃ ) ₃ SiO _1/2 ] _x [SiO ₂ ] ₁ [(CH ₃ ) ₂ SiO] _y [CH ₃ VinSiO] _z },

where x = 0.9 ÷ 1.2, y = 0 ÷ 0.4, z = 0.1 ÷ 0.4

or - silicone resin type MQ (MQT ^Vin ) of the General formula:

{[((CH ₃ ) ₃ SiO _1/2 ] _x [SiO ₂ ] ₁ [VinSiO _1.5 ] _y },

where x = 0.9 ÷ 1.2; y = 0.1 ÷ 0.4.

The vulcanization of silicone elastomers is carried out using a cross-linking agent - oligomethylhydridosiloxane containing 0.50 ÷ 0.62 wt.% Si-H groups having a viscosity of 800 cP and platinum-containing catalyst, for example Spayer catalyst (a solution of platinum chloride in isopropyl alcohol).

A cross-linked dimethyl polysiloxane gel obtained in accordance with RF patent No. 2127746, which is an analogue of the silicone gel described in US Pat. No. 4,455,691, was used as a test component. An additional 20 parts by weight was added to the gel. chemically unbound trimethylsiloxy terminated oligodimethylsiloxane having a viscosity of 1000 cSt. Oligodimethylsiloxane played the role of a component that contributed more to the swelling of the vulcanized composite material. The vulcanization of the gel was carried out at 150 ° C for 2 to 3 hours.

The following examples illustrate the present invention:

Example 1

Silicone composite material is prepared by mixing 100 parts by weight of silicone rubber, which is a polydimethylvinylsiloxane rubber containing 0.12 wt.% vinyl groups, filled with reinforcing silicon dioxide, with 50 wt.h. polyphenylsilsesesquioxanepolydiorganosiloxane block copolymer in which m = 75.695, n = 2.26, p = 360, containing 0.08 wt.% vinyl groups, with 5 ÷ 7 wt. oligomethylhydridesiloxane containing 0.50 wt.% Si-H groups having a viscosity of 800 cP, and 1 wt.h. Spier catalyst.

Silicone rubber is used in the form of 9 ÷ 12% solution in xylene, the block copolymer in the form of 25 ÷ 30% solution in xylene. The calculation of the ingredients of the composition is carried out on a dry residue.

The resulting mixture is discretely poured into a Teflon mold having dimensions of 135 mm × 55 mm × 3 mm. The number of layers applied is determined experimentally in order to obtain a total thickness of vulcanized material of 2.03 ± 0.127 mm. The layers are applied in air at room temperature with an interval of 30-40 minutes. The formed material is kept at room temperature for at least 10 hours, then subjected to heat treatment at 120 ° C for 1 hour or 150 ° C for 30 minutes to more completely remove traces of solvent.

Example 2

Silicone composite material is prepared and vulcanized in the same manner as in Example 1 by mixing 100 parts by weight of silicone rubber, which is a polydimethylvinylsiloxane rubber containing 0.12 wt.% vinyl groups filled with reinforcing silicon dioxide, with 50 wt.h. polyphenylsilsesesquioxane polydiorganosiloxane block copolymer in which m = 57.868, n = 2.288, p = 93, with 5 parts by weight silicone resin type MQ (MQD ^Vin ), where x = 0.9 ÷ 1.2, y = 0 ÷ 0.4, z = 0.1 ÷ 0.4.

Example 3

Silicone composite material is prepared and vulcanized in the same manner as in Example 1 by mixing 100 parts by weight of silicone rubber, which is a polydimethylvinylsiloxane rubber filled with reinforcing silicon dioxide, with 26 wt.h. polyphenylsilsesesquioxanepolydiorganosiloxane block copolymer in which m = 73.976, n = 2.26, p = 195, with 32 parts by weight silicone resin type MQ (MQD ^Vin ), where x = 0.9 ÷ 1.2, y = 0 ÷ 0.4, z = 0.1 ÷ 0.4.

Example 4

Silicone composite material is prepared and vulcanized in the same manner as in Example 1 by mixing 100 parts by weight of polydimethylvinyl diphenylsiloxane rubber containing 0.086 wt.% vinyl groups, 7 mol.% diphenylsiloxane units, with 25 wt. reinforcing silicon dioxide, with 40 wt.h. silicone resin type MQ (MQT ^Vin ), where x = 0.9 ÷ 1.2, y = 0.1 ÷ 0.4.

Example 5

Silicone composite material is prepared and vulcanized in the same manner as in Example 1 by mixing 100 parts by weight of polydimethylvinyl diphenylsiloxane rubber containing 0.086 wt.% vinyl groups, 7 mol.% diphenylsiloxane units, with 25 wt. reinforcing silicon dioxide, with 40 wt.h. silicone resin type MQ (MQD ^Vin ), where x = 0.9 ÷ 1.2, y = 0 ÷ 0.4, z = 0.1 ÷ 0.4.

Example 6

Samples of vulcanized materials obtained in accordance with Examples 1 ÷ 5 are prepared and tested by swelling under the influence of silicone gel (sample preparation and experimental procedure are carried out in accordance with US patent No. 4,455,691 (method ASTM D471)).

Rectangles having dimensions of 25.4 mm × 50.8 mm × 2.03 ± 0.127 mm are cut from sheets of vulcanized materials, weighed in air with an accuracy of mg and placed in ml bottles containing test dimethylsiloxane gel. Boxes with test materials are kept in a heating cabinet at 110 ° C for 22 hours. After thermostating, the samples are cooled in air for 1.5 hours, the rectangles are removed from gel containers and placed on a sheet of filter paper. Excess test gel is removed from the rectangular samples with a wooden spatula. For more thorough removal of excess test gel from the surface of the samples, they are briefly immersed in acetone, carefully blotted with filter paper and dried in air.

Data on the magnitude of the swelling of vulcanized materials are presented in the table:

Example No. The content in the elastomer of diphenylsiloxane units, mol.% The change in weight of the sample,% one - 2.86 2 - 2.70 3 - 5.50 four 7 6.56 5 7 6.48 Prototype* 8 11.22 * According to US Patent No. 4,455,691, which is a prototype, a similar indicator when testing the barrier layer containing 8 mol.% Diphenylsiloxane units, siloxane gel, not containing 20 wt.h. chemically unbound trimethylsiloxy terminated oligodimethylsiloxane having a viscosity of 1000 cSt was 11.22%.

Claims (5)

1. Silicone composite material to obtain a barrier shell based on a composition cured in the presence of polyorganohydride siloxane and a platinum catalyst, characterized in that it includes a polymer binder filled with reinforcing silicon dioxide - polydimethylvinyl siloxane containing 0.12-0.07 wt.% Vinyl groups or polydimethyldiphenylvinylsiloxane containing 0.086 wt.% vinyl groups and not more than 5-8 mol.% diphenylsiloxane units, or mixtures thereof, and contains at least one or a mixture of organosilicon e compound having a phenylsilsesquioxoxane or branched structure containing functional groups capable of chemically binding to the reactive groups of the polymer binder. 2. The silicone composite material according to claim 1, characterized in that when using polydimethylvinylsiloxane as the organosilicon compound, polyphenylsilesesquioxane-polydiorganosiloxane block copolymers of the general formula are used
{[C ₆ H ₅ SiO _1,5 ] _m [C ₆ H ₅ (OH) SiO] _n [R ¹ R ² SiO] _p },
where R ¹ = R ² - CH ₃ -; R ¹ - CH ₃ -, R ² - CH ₂ -CH-,
m = 57.868 ÷ 75.695, n = 2.288 ÷ 3.880, p-93 ÷ 360. 3. The silicone composite material according to claim 1, characterized in that when using polydimethylvinylsiloxane as an organosilicon compound, a mixture of polyphenylsilsesesquioxane-polydiorganosiloxane block copolymer of the general formula
{[C ₆ H ₅ SiO _1,5 ] _m [C ₆ H ₅ (OH) SiO] _n [R ¹ R ² SiO] _p },
where R ¹ = R ² - CH ₃ -; R ¹ - CH ₃ -, R ² - CH ₂ -CH-,
m = 57.868 ÷ 75.695, n = 2.288 ÷ 3.880, p = 93 ÷ 360
and an organosilicon type MQ resin (MQD ^vin ) of the general formula
{[((CH ₃ ) ₃ SiO _1/2 ] _x [SiO ₂ ] ₁ [(CH ₃ ) ₂ SiO] _y [CH ₃ VinSiO] _z },
where x = 0.9 ÷ 1.2, y = 0 ÷ 0.4, z = 0.1 ÷ 0.4. 4. The silicone composite material according to claim 1, characterized in that when using polydimethylvinyl diphenylsiloxane as an organosilicon compound, an organosilicon resin of the type MQ (MQD ^vin ) of the general formula
{[((CH ₃ ) ₃ SiO _1/2 ] _x [SiO ₂ ] ₁ [(CH ₃ ) ₂ SiO] _y [CH ₃ VinSiO] _z },
where x = 0.9 ÷ 1.2, y = 0 ÷ 0.4, z = 0.1 ÷ 0.4. 5. The silicone composite material according to claim 1, characterized in that when using polydimethylvinyl diphenylsiloxane as an organosilicon compound, an organosilicon resin of the type MQ ((MQT ^Vin ) of the general formula
{[((CH ₃ ) ₃ SiO _1/2 ] _x [SiO ₂ ] ₁ [VinSiO _1.5 ] _y },
where x = 0.9 ÷ 1.2, y = 0 ÷ 0.4.