An organosilicon elastomer and its applications

Abstract

This invention discloses an organosilicon elastomer and its applications, belonging to the field of cosmetic materials technology. The organosilicon elastomer comprises a crosslinked polysiloxane and a dispersion medium. The crosslinked polysiloxane is obtained by crosslinking a polysiloxane with α-olefin-terminated long-chain alkyl groups with a hydrogen-containing silicone oil. This invention improves the waterproof performance of the organosilicon elastomer gel and provides moderate film hardness, making it suitable for use in personal care products such as makeup, lipsticks, and foundations.

Description

Technical Field

[0001] This invention relates to an organosilicon elastomer and its applications, belonging to the field of cosmetic technology. Background Technology

[0002] Organosilicon elastomer gels have a wide range of applications in personal care products. They are usually made by pulverizing cross-linked polysiloxanes into fine particles and then dispersing them in dispersion media such as decamethylcyclopentasiloxane or low-viscosity dimethyl silicone oil (e.g., viscosity of 3-5 cSt at 25°C) for swelling.

[0003] To improve the performance of silicone elastomer gels, the industry has made some improvements. For example, the prior art US20040044121A1 discloses the preparation of silicone elastomer gels by crosslinking high molecular weight polysiloxanes containing Si-H and dienes, diynes, or enyne compounds in the presence of a diluent. This prior art replaces vinyl polysiloxanes with dienes, diynes, or enyne compounds. Because dienes, diynes, or enyne compounds have low molecular weights, to avoid the crosslinked polysiloxanes forming excessively hard particles after crushing, which are difficult to disperse in the dispersion medium and have low non-swelling properties, high molecular weight polysiloxanes (degree of polymerization around 400 or higher) are required. However, this method introduces too many dienes, diynes, or enyne compounds. Longer carbon chains in dienes, diynes, or enyne compounds can form a waxy structure, resulting in an overly hard silicone elastomer gel film with a poor user experience.

[0004] Therefore, the existing methods for preparing organosilicon elastomer gels need further optimization. Summary of the Invention

[0005] In order to solve the above-mentioned technical problems, the present invention provides an organosilicon elastomer with good waterproof performance and moderate film hardness.

[0006] Another object of the present invention is to provide an application of the above-mentioned organosilicon elastomer.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] An organosilicon elastomer, characterized in that it comprises a crosslinked polysiloxane and a dispersion medium.

[0009] The crosslinked polysiloxane is obtained by crosslinking the modified polysiloxane shown in formula (1) with hydrogen-containing silicone oil;

[0010] CH2=CH(CH2) c SiMe2O a (SiMeR 1 O) b SiMe2(CH2) cCH=CH2 (1)

[0011] Among them, R 1 Selected from C1-C4 alkyl or C6-C12 aromatic groups, Me represents methyl, a=10-500, b=0-50, c=6-20.

[0012] Preferably, the R 1 Selected from phenyl, b / a = 0.1-0.5, c = 10-20.

[0013] Preferably, the modified polysiloxane is obtained by hydrosilylation reaction of the hydrogen-terminated polysiloxane shown in formula (2) and the diene compound shown in formula (3).

[0014] HSiMe2O(SiMe2O) a (SiMeR 1 O) b SiMe2H (2);

[0015] CH2=CH(CH2) c-2 CH=CH2 (3)

[0016] The molar ratio of the terminal hydrogen polysiloxane to the diene compound is 1:2-10.

[0017] Preferably, the hydrogen-containing silicone oil has a viscosity of 50-500 mPa·s at 25°C, an H content of 0.1-0.5 wt%, and a structure as shown in formula (4).

[0018] R 2 SiMe2O d (SiMeHO) e SiMe2R 2 (4)

[0019] Among them, R 2 Selected from H or C1-C4 alkyl groups, d=10-200, e≥3.

[0020] Preferably, the molar ratio of vinyl groups in the modified polysiloxane to Si-H groups in the hydrogen-containing silicone oil is 1:1.02-1.1.

[0021] Preferably, the dispersion medium is selected from one or both of dimethylsiloxane cyclic compounds and polydimethylsiloxane with a viscosity of 2-10 mPa·s at 25°C.

[0022] Preferably, the weight ratio of the crosslinked polysiloxane to the dispersion medium is 1:5-9.

[0023] Preferably, the organosilicon elastomer of the present invention further comprises a long-chain alkyl hydrogen-containing silicone oil as shown in formula (5), wherein the H content is 0.05-0.2 wt%.

[0024] R 3 SiMe2O f (SiMeHO) g (SiMeR 4 O) h SiMe2R 3 (5)

[0025] Among them, R 3 Selected from H or C1-C4 alkyl, or R 3 With R 4 Same, R 4 Selected from C12-C24 alkyl groups, f=20-200, g>0, h>0, h / g=0.3-2.

[0026] More preferably, the long-chain alkyl hydrogen-containing silicone oil accounts for 2-10% of the weight of the organosilicon elastomer raw material.

[0027] An application of any of the above-described silicone elastomers, characterized in that it is used in cosmetics.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] This invention uses vinyl polysiloxane. Through the hydrosilylation reaction of diene compound with Si-H terminal polysiloxane, the modified polysiloxane obtained has vinyl end groups, and there are multiple carbon atoms between the vinyl group and the nearest Si-O group. This introduces an appropriate amount of long-chain alkyl structure into the organosilicon elastomer, which improves the waterproof performance of the organosilicon elastomer gel and has moderate film hardness.

[0030] The organosilicon elastomer of the present invention further incorporates long-chain alkyl hydrogen-containing silicone oil, introducing a long-chain alkyl structure into the side chain, which further improves the waterproof performance of the organosilicon elastomer gel.

[0031] The organosilicon elastomer of the present invention is suitable for personal care products such as makeup, lipstick, and foundation. Detailed Implementation

[0032] The technical solution of the present invention will be further explained and described below through specific embodiments.

[0033] An organosilicon elastomer, the raw material components of which include cross-linked polysiloxane and dispersion medium;

[0034] The crosslinked polysiloxane is obtained by crosslinking the modified polysiloxane shown in formula (1) with hydrogen-containing silicone oil;

[0035] CH2=CH(CH2) c SiMe2O a (SiMeR 1 O) b SiMe2(CH2) c CH=CH2 (1)

[0036] Among them, R 1 Selected from C1-C4 alkyl or C6-C12 aromatic groups, Me represents methyl, a=10-500, b=0-50, c=6-20.

[0037] In this invention, long-chain α-alkenyl groups (8 carbons or more) are introduced onto the end groups of polysiloxane. The α-alkenyl groups can react with Si-H, and the long-chain alkylene groups can enable the silicone elastomer to form a waxy structure locally after film formation at room temperature, which appropriately improves the film-forming properties and film hardness of the silicone elastomer, thereby improving the waterproof performance of the silicone elastomer.

[0038] For the crosslinking reaction of modified polysiloxanes and hydrogen-containing silicone oils, a Pt-based catalyst can be added for catalysis. The more catalyst added, the faster the reaction rate. For example, the reaction can be carried out overnight at room temperature, or it can be carried out under appropriate heating. To achieve thorough mixing of the crosslinked polysiloxane and the dispersion medium, the modified polysiloxane, hydrogen-containing silicone oil, and dispersion medium can be mixed evenly before crosslinking into a solid. The solid silicone elastomer can then be pulverized (e.g., using a three-roll mill) to obtain a paste-like silicone elastomer gel.

[0039] In some embodiments, R 1 Selected from phenyl, b / a = 0.1-0.5, c = 10-20. R 1 Selected from phenyl groups, it can increase the refractive index of crosslinked polysiloxanes, resulting in better gloss after the silicone elastomer film is formed. c=10-20, meaning the carbon chain of the terminal alkenyl group is longer, which is more conducive to the localized waxy structure of the silicone elastomer film at room temperature, thereby further improving the waterproof performance of the silicone elastomer film. For example, b / a can be any value from 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, etc., without any particular limitation.

[0040] In some embodiments, the modified polysiloxane is obtained by hydrosilylation reaction of a hydrogen-terminated polysiloxane of formula (2) and a diene compound of formula (3).

[0041] HSiMe2O(SiMe2O) a (SiMeR 1 O) bSiMe2H (2),

[0042] CH2=CH(CH2) c-2 CH=CH2 (3),

[0043] The molar ratio of hydrogen-terminated polysiloxane to diene compound is 1:2-10, wherein R 1 Selected from C1-C4 alkyl or C6-C12 aromatic groups, Me represents methyl, a=10-500, b=0-50, c=6-20.

[0044] An excess of diene relative to the hydrogen-terminated polysiloxane allows for grafting of the diene to both ends of the polysiloxane via hydrosilylation, forming α-alkenyl groups with 8-22 carbon chains at the end groups. These alkenyl groups then undergo a crosslinking reaction with hydrosilicone oil to obtain crosslinked polysiloxanes. The preparation method for hydrogen-terminated polysiloxanes is not particularly limited; concentrated sulfuric acid or acidic clay can be used as catalysts, with tetramethyldisiloxane (HSiMe2OSiMe2H) as the end-capping agent. This process is applied to cyclic siloxanes (such as octamethylcyclotetrasiloxane D4 and tetramethyltetraphenylcyclotetrasiloxane D4). ph It undergoes a ring-opening reaction.

[0045] For example, the molar ratio of the terminal hydrogen polysiloxane to the diene compound can be any value or any value between 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, etc., without any particular limitation. The terminal hydrogen polysiloxane and the diene compound undergo a hydrosilylation reaction at a molar ratio of 1:2. If the diene compound is in excess, the excess diene compound can be removed by methods such as vacuum finishing or short-path molecular distillation. To promote the hydrosilylation reaction of the terminal hydrogen polysiloxane and the diene compound at a molar ratio of 1:2, the terminal hydrogen polysiloxane can be added dropwise to the diene compound during the reaction. The hydrosilylation reaction is well known to those skilled in the art and can be carried out under an inert gas atmosphere using a Pt-based catalyst (such as Karstedt catalyst, Speier catalyst, etc.) at 110-140°C.

[0046] For example, diene compounds can be 1,7-octadiene, 1,8-nonadiene, 1,11-dodecadiene, 1,15-hexadecadiene, 1,17-octadecadiene, 1,21-docosadiene, etc.

[0047] In some embodiments, the hydrogen-containing silicone oil has a viscosity of 50-500 mPa·s at 25°C, an H content of 0.1-0.5 wt%, and a structure as shown in formula (4).

[0048] R 2 SiMe2O d (SiMeHO)e SiMe2R 2 (4)

[0049] Among them, R 2 Selected from H or C1-C4 alkyl groups, d=10-200, e≥3.

[0050] Hydrogen-containing silicone oils are obtained directly from the market. For example, the viscosity of hydrogen-containing silicone oils can be any value or any value between 50 mPa·s, 100 mPa·s, 150 mPa·s, 200 mPa·s, 250 mPa·s, 300 mPa·s, 350 mPa·s, 400 mPa·s, 450 mPa·s, and 500 mPa·s, without any particular restrictions; the hydrogen content can be any value or any value between 0.1 wt%, 0.15 wt%, 0.2 wt%, 0.25 wt%, 0.3 wt%, 0.35 wt%, 0.4 wt%, 0.45 wt%, and 0.5 wt%, without any particular restrictions.

[0051] In some embodiments, the molar ratio of vinyl groups in the modified polysiloxane to Si-H groups in the hydrogen-containing silicone oil is 1:1.02-1.1. An appropriate excess of Si-H relative to vinyl groups can promote complete crosslinking. For example, the molar ratio of vinyl groups in the modified polysiloxane to Si-H groups in the hydrogen-containing silicone oil can be any value or any value between 1:1.02, 1:1.03, 1:1.04, 1:1.05, 1:1.06, 1:1.07, 1:1.08, 1:1.09, 1:1.1, etc., without particular limitation.

[0052] In some embodiments, the dispersion medium is selected from one or both of dimethylsiloxane cyclic compounds and polydimethylsiloxanes with a viscosity of 2-10 mPa·s at 25°C. The dimethylsiloxane cyclic compound can be octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), dodecylcyclohexasiloxane (D6), etc. Polydimethylsiloxanes with a viscosity of 2-10 mPa·s at 25°C are generally referred to as low-viscosity silicone oils, and their viscosities can be 2 mPa·s, 3 mPa·s, 4 mPa·s, 5 mPa·s, 6 mPa·s, 7 mPa·s, 8 mPa·s, 9 mPa·s, 10 mPa·s, etc.

[0053] In some embodiments, the weight ratio of crosslinked polysiloxane to dispersion medium is 1:5-9. For example, the weight ratio of crosslinked polysiloxane to dispersion medium can be any value or any value between 1:5, 1:5.5, 1:6, 1:6.5, 1:7, 1:7.5, 1:8, 1:8.5, 1:9, etc., without any particular limitation.

[0054] In some embodiments, the raw material components of the organosilicon elastomer further include a long-chain alkyl hydrogen-containing silicone oil as shown in formula (5), wherein the H content is 0.05-0.2 wt%.

[0055] R 3 SiMe2O f (SiMeHO) g (SiMeR 4 O) h SiMe2R 3 (5)

[0056] Among them, R 3 Selected from H or C1-C4 alkyl, or R 3 With R 4 Same, R 4 Selected from C12-C24 alkyl groups, f=20-200, g>0, h>0, h / g=0.3-2.

[0057] Long-chain alkyl hydrogen-containing silicone oil is further added to the raw materials of organosilicon elastomers. The R in the long-chain alkyl hydrogen-containing silicone oil... 4 By giving it a waxy structure at room temperature, Si-H can participate in the cross-linking reaction. Therefore, the addition of long-chain alkyl hydrogen-containing silicone oil can further form a local waxy structure during the film formation of silicone elastomers, thereby improving the film-forming properties of silicone elastomers and enhancing their waterproof performance.

[0058] For example, the h / g value can be 0.3, 0.5, 0.7, 0.8, 1, 1.2, 1.5, 1.7, 1.8, 2, etc.

[0059] For the long-chain alkyl hydrogen-containing silicone oil shown in formula (5) above, it can be obtained from the corresponding hydrogen-containing silicone oil R. 3 SiMe2O f (SiMeHO) g+h SiMe2R 3 It is obtained by hydrosilylation reaction with C12-C24 α-olefins at a molar ratio of 1:h.

[0060] In some embodiments, the weight percentage of long-chain alkyl hydrogen-containing silicone oil in the silicone elastomer is 2-10%. For example, the weight percentage of long-chain alkyl hydrogen-containing silicone oil in the silicone elastomer can be 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc.

[0061] On the other hand, the present invention also proposes an application of the silicone elastomer described in any of the above embodiments in cosmetics. The silicone elastomer of the present invention has good film-forming properties and film-forming waterproof properties. When applied to cosmetics, especially makeup, mascara, foundation, lipstick and other cosmetics that require good waterproof performance, it can improve their water resistance, for example, it can prevent or delay the fading of makeup under sweat.

[0062] The technical solution of the present invention will be further described and explained below with reference to various preparation examples and embodiments. Unless otherwise specified, the parts mentioned in the following preparation examples and embodiments are parts by weight.

[0063] Preparation Examples 1-4: Preparation of Modified Polysiloxanes

[0064] Preparation Example 1

[0065] The structure of the hydrogen-terminated polysiloxane is shown in formula (2) above, where a=110 and b=0.

[0066] The molar ratio of 1,21-docosadiene to hydrogen-terminated polysiloxane is 2:1.

[0067] 1,21-Eocodecanediene was added to the reaction vessel, nitrogen gas was purged, the temperature was raised to 90°C, Karstedt catalyst (10 ppm based on Pt) was added, and terminal hydrogen polysiloxane was added dropwise. The reaction temperature was controlled not to exceed 135°C. After the addition was complete, the reaction was continued at 130-135°C for 3 hours. No Si-H groups were detected in the reaction system. The temperature was then lowered to obtain the modified polysiloxane.

[0068] Preparation Example 2

[0069] The molar ratio of 1,11-dodecadiene to the hydrogen-terminated polysiloxane in Preparation Example 1 was 3:1.

[0070] 1,11-dodecanediene was added to a reaction vessel, protected with nitrogen, and the temperature was raised to 90°C. Karstedt catalyst (10 ppm based on Pt) was added, and terminal hydrogen polysiloxane was added dropwise. The reaction temperature was controlled to not exceed 135°C. After the addition was complete, the reaction was continued at 130-135°C for 2 hours. No Si-H groups were detected in the reaction system. The pressure was reduced to below 100 Pa, and unreacted 1,11-dodecanediene was removed by vacuum distillation. The temperature was then lowered to obtain modified polysiloxane.

[0071] Preparation Example 3

[0072] The molar ratio of 1,7-octadiene to the hydrogen-terminated polysiloxane in Preparation Example 1 is 3:1.

[0073] 1,7-Octopadiene was added to a reaction vessel, protected with nitrogen, and the temperature was raised to 90°C. Karstedt catalyst (10 ppm based on Pt) was added, and terminal hydrogen polysiloxane was added dropwise. The reaction temperature was controlled to not exceed 135°C. After the addition was complete, the reaction was continued at 130-135°C for 3 hours. No Si-H groups were detected in the reaction system. The pressure was reduced to below 500 Pa, and unreacted 1,7-octadiene was removed by vacuum distillation. The temperature was then lowered to obtain modified polysiloxane.

[0074] Preparation Example 4

[0075] The structure of the hydrogen-terminated polysiloxane is shown in formula (2) above, where a=200 and b=40.

[0076] The molar ratio of 1,15-hexadecadiene to hydrogen-terminated polysiloxane is 4:1.

[0077] 1,15-hexadecadiene was added to a reaction vessel, protected with nitrogen, and the temperature was raised to 90°C. Karstedt catalyst (10 ppm based on Pt) was added, and terminal hydrogen polysiloxane was added dropwise. The reaction temperature was controlled not to exceed 135°C. After the addition was complete, the reaction was continued at 130-135°C for 2 hours. No Si-H groups were detected in the reaction system. The pressure was reduced to below 50 Pa, and the temperature was raised to 160°C to remove unreacted 1,15-hexadecadiene by vacuum distillation. The temperature was then lowered to obtain modified polysiloxane.

[0078] Comparative Preparation Example 1

[0079] The comparative preparation example uses a vinyl-terminated polysiloxane with the structure ViSiMe2O(SiMe2O). 116 SiMe2Vi.

[0080] Comparative Preparation Example 2

[0081] The comparative preparation example is 1,11-dodecanediene.

[0082] Examples 1-9 Preparation of Organosilicon Elastomers

[0083] Example 1

[0084] The hydrogen-containing silicone oil is as shown in formula (4) above, with a viscosity (25℃) of 130 mPa·s and an H content of 0.28 wt%.

[0085] In the modified polysiloxane of Preparation Example 1, the molar ratio of vinyl groups to Si-H in the hydrogen-containing silicone oil was 1:1.05.

[0086] The ratio of the weight of the modified polysiloxane and the hydrogen-containing silicone oil to the weight of D6 is 1:7.

[0087] Modified polysiloxane, hydrogen-containing silicone oil and D6 were added to a container, and then Speier catalyst (15 ppm based on Pt) was added. The mixture was stirred and mixed evenly, and placed at 50°C for 6 hours to obtain a solid organosilicon elastomer.

[0088] Solid silicone elastomers were pulverized using a three-roll mill to obtain a paste-like silicone elastomer gel.

[0089] Example 2

[0090] The difference between this embodiment and Example 1 is that in Example 1, the modified polysiloxane used in Preparation Example 1 was replaced with the modified polysiloxane used in Preparation Example 2. All other steps remained unchanged.

[0091] Example 3

[0092] The difference between this embodiment and Example 1 is that in Example 1, the modified polysiloxane used in Preparation Example 1 was replaced with the modified polysiloxane used in Preparation Example 3. All other steps remained unchanged.

[0093] Example 4

[0094] The difference between this embodiment and Example 1 is that in Example 1, the modified polysiloxane used in Preparation Example 1 was replaced with the modified polysiloxane used in Preparation Example 4. All other steps remained unchanged.

[0095] Comparative Example 1

[0096] The difference between this comparative example and Example 1 is that in Example 1, the modified polysiloxane of Preparation Example 1 was replaced with the vinyl-terminated polysiloxane of Comparative Preparation Example 1. All other steps remained unchanged.

[0097] Comparative Example 2

[0098] The difference between this comparative example and Example 1 is that in Example 1, the modified polysiloxane used in Preparation Example 1 was replaced with 1,11-dodecanediene used in Comparative Preparation Example 2. All other steps remained unchanged.

[0099] Example 5

[0100] The hydrogen-containing silicone oil is as shown in formula (4) above, with a viscosity (25℃) of 280 mPa·s and an H content of 0.21 wt%.

[0101] In the modified polysiloxane of Preparation Example 2, the molar ratio of vinyl groups to Si-H in the hydrogen-containing silicone oil was 1:1.04.

[0102] The ratio of the sum of the weights of the modified polysiloxane and the hydrogen-containing silicone oil to the weight of the dimethyl silicone oil with a viscosity (25℃) of 3 mPa·s is 1:9.

[0103] Modified polysiloxane, hydrogen-containing silicone oil and dimethyl silicone oil were added to a container, and then Speier catalyst (15 ppm based on Pt) was added. The mixture was stirred and mixed evenly, and placed at 50°C for 6 hours to obtain a solid organosilicon elastomer.

[0104] Solid silicone elastomers were pulverized using a three-roll mill to obtain a paste-like silicone elastomer gel.

[0105] Example 6

[0106] The difference between this embodiment and Embodiment 5 is that in Embodiment 5, before the mixture is stirred and homogenized, a long-chain alkyl hydrogen-containing silicone oil accounting for 2 wt% of the weight of the silicone elastomer raw material is added to the silicone elastomer. The molar amount of Si-H in the reaction system remains unchanged, that is, the weight of the hydrogen-containing silicone oil is reduced accordingly. The remaining steps remain unchanged.

[0107] Long-chain alkyl hydrogen-containing silicone oils are SiMe3O (SiMe2O). 70 (SiMeHO) 18 (SiMeR 4 O) 11 SiMe3,R 4 It is an octadecyl group.

[0108] Example 7

[0109] The difference between this embodiment and Embodiment 6 is that in Embodiment 6, the weight percentage of long-chain alkyl hydrogen-containing silicone oil in the organosilicon elastomer is adjusted from 2% to 5%. The remaining steps remain unchanged.

[0110] Example 8

[0111] The difference between this embodiment and Embodiment 6 is that in Embodiment 6, the weight percentage of long-chain alkyl hydrogen-containing silicone oil in the organosilicon elastomer composition was adjusted from 2% to 10%. The remaining steps remain unchanged.

[0112] Example 9

[0113] The difference between this embodiment and Embodiment 5 is that in Embodiment 5, before the mixture is stirred and homogenized, a long-chain alkyl hydrogen-containing silicone oil accounting for 5 wt% of the weight of the silicone elastomer composition is added to the silicone elastomer composition. The molar amount of Si-H in the reaction system remains unchanged, that is, the weight of the hydrogen-containing silicone oil is reduced accordingly. The remaining steps remain unchanged.

[0114] Long-chain alkyl hydrogen-containing silicone oils are SiMe3O (SiMe2O). 105 (SiMeHO) 15 (SiMeR 4 O) 27 SiMe3,R 4 It is a dodecyl group.

[0115] Performance testing

[0116] Hydrophobic angle: The silicone elastomer gel to be tested is placed on a clean glass surface at a concentration of 2 mg / cm². 2 The coating is applied to form a film, and the hydrophobic angle (i.e., contact angle) is tested using a water contact angle tester.

[0117] Film-forming and waterproof performance evaluation: The silicone elastomer gels prepared in Examples 1-9 and Comparative Examples 1-2 were diluted with 9 times their volume of dodecylcyclohexasiloxane. Ten trained female volunteers aged 20-35 were selected. Every morning after facial cleansing, 0.7g of the diluted silicone elastomer gel was applied to the face and washed off before bedtime. After one week, the film-forming and waterproof performance scores were evaluated. The highest and lowest scores were removed, and the average of the remaining 8 scores was taken. Film-forming performance was scored out of 5: 5 points, good film-forming performance, suitable softness and hardness, and no impact on breathability; 4 points, relatively good film-forming performance, suitable softness and hardness, and no impact on breathability; 3 points, relatively good film-forming performance, average breathability or slightly firm softness and hardness; 2 points, average film-forming performance or slightly firm softness and hardness, and average breathability; 1 point, poor film-forming performance or relatively firm softness and hardness, and poor breathability. Waterproofing performance is rated on a scale of 5: 5 points for excellent waterproofing; 4 points for good waterproofing; 3 points for average waterproofing; 2 points for poor waterproofing; and 1 point for very poor waterproofing. The results are shown in Table 1 below.

[0118] Table 1:

[0119] Hydrophobic angle / ° Film-forming properties / Water resistance / parts Hydrophobic angle / ° Film-forming properties / Water resistance / parts Example 1 114 4.1 4.6 Example 5 110 4.2 4.6 Example 2 110 4.3 4.4 Example 6 112 4.4 4.8 Example 3 108 4.8 4.0 Example 7 114 4.5 5.0 Example 4 111 4.4 4.5 Example 8 115 4.7 5.0 Comparative Example 1 105 3.8 3.4 Example 9 113 4.5 4.6 Comparative Example 2 109 3.1 4.0

[0120] Therefore, as can be seen from the data in Table 1 above, the organosilicon elastomer of this application has good hydrophobicity after coating and film formation, and has good film formation and waterproof properties on the face.

[0121] As described above, the basic principles, main features, and advantages of the present invention have been shown and described. Those skilled in the art should understand that the present invention is not limited to the above embodiments, which are merely preferred embodiments and should not be construed as limiting the scope of the invention. All equivalent changes and modifications made in accordance with the scope of the patent and the description should still fall within the scope of the present invention. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. An organosilicon elastomer, characterized in that: The mixture includes a crosslinked polysiloxane and a dispersion medium, wherein the crosslinked polysiloxane is prepared by crosslinking a modified polysiloxane of formula (1) with a hydrogen-containing silicone oil: CH2=CH(CH2) c SiMe2O(SiMe2O) a (SiMeR 1 Oh) b SiMe2(CH2) c CH=CH2 (1) Among them, R 1 Selected from C1-C4 alkyl or C6-C12 aromatic groups, Me represents methyl, a=10-500, b=0-50, c=6-20.

2. The organosilicon elastomer according to claim 1, characterized in that: The R 1 Selected from phenyl, b / a = 0.1-0.5, c = 10-20.

3. The organosilicon elastomer according to claim 1, characterized in that: The modified polysiloxane is obtained by hydrosilylation reaction of the hydrogen-terminated polysiloxane shown in formula (2) and the diene compound shown in formula (3). HSiMe2O(SiMe2O) a (SiMeR 1 O) b SiMe2H (2), CH2=CH(CH2) c-2 CH=CH2 (3), The molar ratio of the terminal hydrogen polysiloxane to the diene compound is 1:2-10.

4. The organosilicon elastomer according to claim 1, characterized in that: The hydrogen-containing silicone oil has a viscosity of 50-500 mPa·s at 25°C, an H content of 0.1-0.5 wt%, and a structure as shown in formula (4). R 2 SiMe2O(SiMe2O) d (SiMeHO) e SiMe2R 2 (4) Among them, R 2 Selected from H or C1-C4 alkyl groups, d=10-200, e≥3.

5. The organosilicon elastomer according to claim 1, characterized in that: The molar ratio of vinyl groups in the modified polysiloxane to Si-H groups in the hydrogen-containing silicone oil is 1:1.02-1.

1.

6. The organosilicon elastomer according to claim 1, characterized in that: The dispersion medium is selected from one or two of dimethylsiloxane cyclic compounds and polydimethylsiloxane with a viscosity of 2-10 mPa·s at 25°C.

7. The organosilicon elastomer according to claim 1, characterized in that: The weight ratio of the crosslinked polysiloxane to the dispersion medium is 1:5-9.

8. The organosilicon elastomer according to claim 1, characterized in that: It also contains long-chain alkyl hydrogen-containing silicone oil as shown in formula (5), with an H content of 0.05-0.2 wt%. R 3 SiMe2O(SiMe2O) f (SiMeHO) g (SiMeR 4 Oh) h SiMe2R 3 (5) Among them, R 3 Selected from H or C1-C4 alkyl, or R 3 With R 4 Same, R 4 Selected from C12-C24 alkyl groups, f=20-200, g>0, h>0, h / g=0.3-2.

9. The organosilicon elastomer according to claim 8, characterized in that: The long-chain alkyl hydrogen-containing silicone oil accounts for 2-10% of the weight of the organosilicon elastomer raw material.

10. An application of the organosilicon elastomer according to any one of claims 1-9, characterized in that: Used in cosmetics.