Silica gel, silica gel product and preparation method thereof

Abstract

The invention relates to the field of organic silicon, in particular to silica gel, a silica gel product and a preparation method of the silica gel product. The silica gel is prepared from the following components in parts by mass: 80 to 90 parts of vinyl silicone oil, 0 to 10 parts of silicon resin, 3 to 50 parts of hydrogen-containing silicone oil, 0.1 to 1.25 parts of an anti-aging agent, 0.1 to 1 part of a platinum catalyst and 0.001 to 0.01 part of an inhibitor, wherein the molar ratio of hydrogen content to vinyl content is gt; 1; the anti-aging agent is a reactive anti-aging agent and participates in the reaction in the vulcanization process of the silica gel, and a compound generated after the reaction can influence the activity of the platinum catalyst. The adhesive layer of the breast patch can keep viscosity to skin and the like for a long time under the condition of medium and low temperature.

Description

Technical Field

[0001] The present invention relates to the field of organic silicon, and more specifically, to a silicone gel, a silicone gel product and a preparation method thereof. Background Art

[0002] Silicone gel is a type of low cross-link density silicone rubber without fillers. It is environmentally friendly, non-toxic and tasteless. Silicone gel is different from ordinary silicone rubber elastomers. It has a transparent or translucent gel appearance and very low mechanical strength. In addition to the advantages of general silicone materials such as safety, non-toxicity and good biocompatibility, silicone gel also has the properties of gel-like substances such as vibration absorption and adhesion. It has been widely used in wearable devices, medical dressings, medical prostheses, electronic and electrical potting and other fields.

[0003] Nipple stickers are a kind of stickers that replace bras to achieve the effect of invisible underwear. They make people feel comfortable, safe, and beautiful, and have a decorative effect from a visual perspective. Nipple stickers mainly include three parts: base material, adhesive layer, and release film. The base materials involved in nipple stickers are mainly silicone and sponge cups. Silicone includes liquid silicone rubber, mixed silicone rubber, and products made by filling liquid silicone rubber in TPU film and then vulcanizing (the surface of the product is TPU film). Sponge cups are mainly composed of one or more of sponge, polyester, cloth, etc., and have larger pores than silicone. The adhesive layer is the adhesive layer of the nipple sticker. After vulcanization, it must have good adhesion to the base material and appropriate adhesion to the skin. At the same time, it must have moderate strength, that is, no adhesive residue should remain on the skin / release film during use.

[0004] Among the prior art patents on silicone gels, most involve silicone gels in the fields of medical health or electronic and electrical potting, while there are fewer patents on nipple patches and chest patches. Moreover, there is also such a technical problem in the field of nipple patches. When the molar ratio of hydrogen content / vinyl content (H / Vi) is greater than 1, that is, when there is a large excess of hydrogen, the large excess of hydrogen will continue to dehydrogenate in the presence of a platinum catalyst, causing the colloid to continue to age and affect its use. Therefore, it is very meaningful to develop a nipple patch adhesive layer that is storage-resistant and anti-aging when the molar ratio of hydrogen content / vinyl content (H / Vi) is greater than 1. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a silicone gel, which comprises, by mass: 80 to 90 parts of vinyl silicone oil, 0 to 10 parts of silicone resin, 3 to 50 parts of hydrogen-containing silicone oil, 0.1 to 1.25 parts of an anti-aging agent, 0.1 to 1 parts of a platinum catalyst and 0.001 to 0.01 parts of an inhibitor;

[0006] Wherein, the molar ratio of hydrogen content / vinyl content is >1;

[0007] The anti-aging agent is a reactive anti-aging agent, which participates in the reaction during the silicone gel vulcanization process, and the compounds generated after the reaction can affect the activity of the platinum catalyst.

[0008] Further, the N-containing substance is a substance containing an isocyanate group;

[0009] Furthermore, the anti-aging agent includes one or more of tris(3-trimethoxysilylpropyl)isocyanurate and 1,3,5-tris(trimethoxysilylpropyl)polyisocyanate.

[0010] Furthermore, the vinyl content of the vinyl silicone oil is 0.1 to 10 wt % and the viscosity is 100 to 200000 mPa·s.

[0011] Furthermore, the silicone resin is vinyl MQ silicone resin.

[0012] Furthermore, the average molecular weight Mn of the silicone resin is 2000-5000, and the molar ratio of the M / Q group is 0.6-0.9.

[0013] Furthermore, the hydrogen atom content is 0.001-1 wt%.

[0014] Furthermore, the hydrogen-containing silicone oil is a mixture of terminal methyl side hydrogen-containing silicone oil and terminal hydrogen-containing silicone oil.

[0015] Furthermore, the inhibitor is one or a mixture of more than one of 1-ethynyl-1-cyclohexanol, 2-methyl-3-butynyl-2-ol, 3-methyl-1-ethynyl-3-ol or 3,5-dimethyl-1-hexynyl-3-ol.

[0016] The present invention also provides a silicone gel product, which is obtained by coating the silicone gel on a substrate and then heating and vulcanizing it.

[0017] The present invention also provides a method for preparing a silicone gel product, comprising the following steps:

[0018] Vinyl silicone oil, silicone resin, hydrogen-containing silicone oil, inhibitor and anti-aging agent are mixed in proportion, stirred evenly, and a catalyst is added and stirred evenly to obtain silicone gel;

[0019] The silicone gel is coated on a substrate, heated and vulcanized to obtain the silicone gel product, the heating temperature is 100-150° C., and the vulcanization time is 2-30 minutes.

[0020] Beneficial effects of this patent:

[0021] The nipple adhesive layer prepared by the invention can maintain the stickiness to the skin for a long time under the condition of medium and low temperature, that is, it solves the problem of the stickiness reduction of the nipple due to long-term aging (storage), and through the combination of vinyl silicone oil and hydrogen-containing silicone oil, when the molar amount of hydrogen content / vinyl content (H / Vi) is greater than 1 and the cone penetration of silicone gel is between 200 and 260, it can be applied to various substrates such as mixed silicone rubber, liquid silicone rubber, TPU, sponge cups and the like involved in the nipple, and has good adhesion, and at the same time has good stickiness to the skin, the obtained nipple product has excellent performance and good versatility, and can also be applied to wearable silicone, medical dressings, scar patches and the like, and has broad market prospects.

[0022] The anti-aging agent used in the present invention is a reactive anti-aging agent, which can effectively promote the adhesion between the adhesive layer of the nipple patch and the substrate. At the same time, under medium and low temperature conditions, the anti-aging agent participates in the vulcanization process, and the N-containing substances generated after the reaction affect the activity of the platinum catalyst, thereby reducing the activity of the platinum catalyst, further playing an anti-aging role, and can effectively inhibit the decrease in viscosity of the adhesive layer of the nipple patch during storage, solve the problem of the decrease in viscosity of the nipple patch under long-term aging, and achieve the anti-aging effect.

[0023] The silicone gel provided by the present invention couples and bonds with the vinyl, active hydrogen, hydroxyl and the like on the surfaces of various substrates of the nipple patch through the combined action of the vinyl and active hydrogen groups of the rubber material itself and the nitrogen-containing active groups such as the isocyanate groups in the anti-aging agent, so that the prepared nipple patch adhesive layer is firmly bonded to various substrates.

[0024] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is the infrared spectrum of Example 3 before and after high temperature vulcanization. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described in conjunction with the appendix of the specific embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] An embodiment of the present invention provides a silicone gel, which includes, by mass, 80 to 90 parts of vinyl silicone oil, 0 to 10 parts of silicone resin, 3 to 50 parts of hydrogen-containing silicone oil, 0.1 to 1.25 parts of an anti-aging agent, 0.1 to 1 parts of a platinum catalyst and 0.001 to 0.01 parts of an inhibitor; wherein the molar ratio of hydrogen content to vinyl content is >1; the anti-aging agent is a reactive anti-aging agent, which participates in the reaction during the vulcanization process of the silicone gel, and the compound generated after the reaction can affect the activity of the platinum catalyst.

[0028] The anti-aging agent described in the present invention is a reactive anti-aging agent. On the one hand, it does not affect the activity of initial platinum and other catalysts, but can react chemically with the coated substrate during the silicone gel vulcanization process to greatly promote adhesion; on the other hand, the anti-aging agent undergoes thermal decomposition reaction to generate inhibitory substances such as urea and ammonia. At the same time, the anti-aging agent can also react with hydrogen-containing substances to promote adhesion. The produced substances such as carbamate also have a certain effect of inhibiting aging, which can effectively inhibit the decrease in viscosity of the nipple adhesive layer during storage.

[0029] In another embodiment of the present invention, the N-containing compound is a substance containing an isocyanate group.

[0030] In another embodiment of the present invention, the anti-aging agent includes one or more of tris(3-trimethoxysilylpropyl)isocyanurate and 1,3,5-tris(trimethoxysilylpropyl)polyisocyanate.

[0031] The silicone gel provided by the present invention uses hydrogen-containing silicone oil as a crosslinking agent, and the hydrogen atom content is 0.001-1wt%.

[0032] In another embodiment of the present invention, the hydrogen-containing silicone oil is a mixture of terminal methyl side hydrogen-containing silicone oil and terminal hydrogen-containing silicone oil. By introducing the terminal hydrogen-containing silicone oil, the hardness and stickiness of the silicone gel to the skin can be adjusted.

[0033] The silicone gel provided by the present invention, when the molar ratio of hydrogen content / vinyl content (H / Vi) is greater than 1 and the cone penetration of the silicone gel is between 200 and 260, can be applied to various substrates such as mixed silicone rubber, liquid silicone rubber, TPU, sponge cups, etc. involved in nipple covers and has good adhesion and good adhesion to the skin. The obtained nipple cover product has excellent performance and good versatility.

[0034] In another embodiment of the present invention, the silicone resin is vinyl MQ silicone resin.

[0035] As an example, the average molecular weight Mn of the vinyl MQ silicone resin is 2000-5000, for example, it can be 2000, 2500, 3000, 3500, 4000, 4500 or 5000, wherein the M / Q group molar ratio of the vinyl MQ silicone resin is 0.6-0.9, preferably 0.6-0.8, and the vinyl content of the vinyl MQ silicone resin (the content of vinyl in silicone oil determined by iodine titration) is 0.1-10wt%, preferably 1-5wt%.

[0036] In another embodiment of the present invention, the viscosity of the vinyl silicone oil at 25°C is 100-200000 mPa·s, for example, it may be 1000 mPa·s, 10000 mPa·s, 20000 mPa·s, 50000 mPa·s or 100000 mPa·s, etc.; the vinyl content of the vinyl silicone oil is 0.1-10wt%, preferably 0.1-1wt%, for example, it may be 0.1wt%, 0.2wt%, 0.3wt%, 0.9wt% or 1wt%, etc.

[0037] In another embodiment of the present invention, the vinyl silicone oil is a methyl-terminated vinyl silicone oil.

[0038] In another embodiment of the present invention, the inhibitor is one or a mixture of more than one of 1-ethynyl-1-cyclohexanol, 2-methyl-3-butynyl-2-ol, 3-methyl-1-ethynyl-3-ol or 3,5-dimethyl-1-hexynyl-3-ol.

[0039] The silicone gel provided by the present invention couples and bonds with the vinyl, active hydrogen, hydroxyl and the like on the surface of various substrates of the nipple patch through the combined action of the vinyl and active hydrogen groups of the rubber material itself and the active groups such as the isocyanate group in the anti-aging agent, so that the prepared nipple patch adhesive layer is firmly bonded to various substrates.

[0040] The present invention also provides a silicone gel product, which is obtained by coating the silicone gel on a substrate and then heating and vulcanizing it.

[0041] Furthermore, the silicone gel product is an adjustable, anti-aging nipple adhesive layer.

[0042] In another embodiment of the present invention, the nipple adhesive layer can be applied to various substrates such as compound silicone rubber, liquid silicone rubber, TPU, sponge cups, etc.

[0043] In another embodiment of the present invention, the adhesive layer of the nipple patch of the present invention is also applicable to the fields of wearing silicone, medical dressings, scar patches, etc., and has a wide range of applications and better meets the use requirements. In addition, the adhesive layer of the nipple patch of the present invention is expected to produce significant economic benefits and has broad market prospects.

[0044] In another embodiment of the present invention, a method for preparing a silicone gel product is provided, comprising the following steps:

[0045] Vinyl silicone oil, silicone resin, hydrogen-containing silicone oil, inhibitor and anti-aging agent are mixed in proportion, stirred evenly, and a catalyst is added and stirred evenly to obtain silicone gel;

[0046] The silicone gel is coated on a substrate, and heated and vulcanized to obtain the silicone gel product. In another embodiment of the present invention, the heating temperature is 100-150° C., and the vulcanization time is 2-30 minutes.

[0047] In another embodiment of the present invention, the substrate is at least one of compound silicone rubber, liquid silicone rubber or TPU.

[0048] Several embodiments and comparative examples of silicone gel specifically involved in the research and development process of the present invention are listed below to facilitate a better understanding of the present invention. The raw material composition is shown in Table 1 below.

[0049] Table 1 is based on the addition of 8 parts of silicone resin, 85 parts of vinyl silicone oil, 0.01 parts of inhibitor, and 0.3 parts of platinum catalyst. Liquid silicone rubber substrate adhesion represents: when silicone gel is applied to liquid glue substrate, adhesion to substrate / adhesion to skin before aging / adhesion to skin after aging for 3 months; solid silicone rubber and other substrates represent the same meaning.

[0050] Table 1 Silicone gel ratio and test results of the embodiments and comparative examples

[0051]

[0052] Note: After the product of comparative example 3 is vulcanized, some residual adhesive adheres to the skin and the release film when it is peeled off for use

[0053] Table 2 is based on the addition of 8 parts of MQ silicone resin, 85 parts of vinyl silicone oil, 10 parts of methyl side hydrogen silicone oil, 20 parts of terminal hydrogen silicone oil, 0.01 parts of inhibitor, and 0.3 parts of platinum catalyst. Viscosity represents: the viscosity of silicone gel when mixed evenly according to the formula without adding catalyst / the viscosity of silicone gel after adding catalyst according to the formula and storing at room temperature for 60 minutes.

[0054] Table 2 Silicone gel ratios and test results of the embodiments and comparative examples

[0055]

[0056] Note: After the product of comparative example 5 is vulcanized, some residual adhesive adheres to the skin and the release film when it is peeled off for use

[0057] The raw materials in Table 1 are used in parts by mass, and the same measurement unit can be used when weighing. Enlarging or reducing the same multiple will not affect the properties of the final silicone gel.

[0058] The MQ silicone resin in Table 1 is a vinyl silicone resin, wherein the M / Q group molar ratio of the MQ silicone resin is 0.65, the average molecular weight Mn is 2900, and the vinyl content is 3.5 wt %.

[0059] The vinyl silicone oils in Table 1 are all methyl-terminated vinyl silicone oils, wherein the viscosity of the vinyl silicone oil at 25° C. is 60,000 mPa·s and the vinyl content is 0.3 wt %.

[0060] The viscosity of the terminal methyl side hydrogen silicone oil in Table 1 is 35 cs at 25°C, and the hydrogen atom content is 0.1 wt%; the viscosity of the terminal hydrogen silicone oil is 90 cs at 25°C, and the hydrogen atom content is 0.04 wt%.

[0061] The catalysts in Table 1 are all platinum catalysts, and their main components are polysiloxane and platinum (0) divinyltetramethyldisiloxane.

[0062] The inhibitor in Table 1 is 1-ethynyl-1-cyclohexanol.

[0063] In Table 2, the anti-aging agent 1 is tris(3-trimethoxysilylpropyl)isocyanurate, the anti-aging agent 2 is 1,3,5-tris(trimethoxysilylpropyl)polyisocyanate, the anti-aging agent 3 is γ-aminopropyltriethoxysilane, and the anti-aging agent 4 is triazole.

[0064] Test example

[0065] The raw materials in Examples 1 to 9 and Comparative Examples 1 to 7 are weighed in proportion by mass, and then mixed and stirred evenly, and then evacuated until there are no bubbles. A certain mass of rubber is weighed, and after high-temperature vulcanization for a certain period of time, it is placed at room temperature to obtain a cone penetration sample; the vacuumed rubber is then coated on the liquid silicone rubber, solid silicone rubber, TPU film, and sponge cup substrate corresponding to the nipple patch, respectively, and high-temperature vulcanization is performed to obtain a nipple patch product. The cone penetration samples obtained above and the finished nipple patch products formed after the nipple patch adhesive layer is vulcanized on various substrates are placed in an oven at 60°C for 3 months of aging test, and the changes in the cone penetration after aging and the adhesion of the nipple patch products to the skin are observed. The test results of the cone penetration and the adhesion of the nipple patch adhesive layer to the skin before and after aging when applied to the surfaces of various substrates are shown in Tables 1 and 2

[0066] The test method for cone penetration refers to DIN ISO 2137.

[0067] The adhesion between the adhesive layer of the nipple patch and the base material / skin is set at levels 1-7, with the larger the number, the better the adhesion.

[0068] It can be seen from Examples 1 and 2 and Comparative Examples 1 and 3 in Table 1 that when the cone penetration of the prepared silicone gel is similar, the bonding effect to liquid silicone rubber, solid silicone rubber and TPU film substrate is generally better than that of H / Vi<1 when H / Vi>1.

[0069] From the comparison of Examples 1-4 and Comparative Examples 2-4 in Table 1, it can be seen that when H / Vi>1, the more the amount of end-hydrogenated silicone oil added, the greater the cone penetration of the prepared silicone gel, that is, the rubber material gradually softens, which is manifested as the adhesion to the skin first increases and then decreases. Comparative Example 3 shows low strength and residual glue after use, and the viscosity is reduced compared with Example 4. Comparative Examples 1 and 2 show poor adhesion to the skin. Therefore, when H / Vi>1, the cone penetration of silicone gel within 200-260 is more suitable for the adhesive layer of the nipple patch.

[0070] It can be clearly seen from the comparison between Examples 3, 5-9 and Comparative Example 5 in Table 2 that the addition of an anti-aging agent can effectively inhibit the decrease in cone penetration and skin adhesion. This is because the N-containing compounds (such as Figure 1 , is the infrared spectrum of Example 3 before and after high temperature vulcanization. It can be seen that before vulcanization, at 2270 cm -1 The infrared characteristic peak of isocyanate at about 1720cm -1 The infrared characteristic peaks of new carbamates are generated around 60°C, which is caused by the breaking of chemical bonds and the formation of new bonds during high-temperature vulcanization. During the three-month aging process at 60°C, the decrease in viscosity caused by the continued reaction of the rubber in the adhesive layer of the nipple patch can be effectively suppressed, so that the adhesive layer of the nipple patch can maintain good adhesion to the skin at medium and low temperatures for a long time. At the same time, it can be seen that the addition of anti-aging agents can effectively promote the adhesion of silicone gel to liquid silicone rubber, solid silicone rubber, and TPU film. This is because the active groups in the anti-aging additives couple and bond with the vinyl, active hydrogen, hydroxyl and other groups on the surface of the substrate, so that the adhesive layer of the nipple patch is better bonded to the substrate.

[0071] From Table 1 and Table 2, the adhesive layer of the breast cover has good adhesion to the sponge cup at the H / Vi ratio of each embodiment and the comparative example. This is because the sponge cup has relatively large gaps, and the rubber material can partially penetrate into the substrate and then be vulcanized and formed.

[0072] It can be clearly seen from the comparison between Examples 3, 5-8 and Comparative Example 5 in Table 2 that the addition of reactive anti-aging agents can effectively inhibit the decrease in cone penetration and skin adhesion. However, when the amount of the anti-aging agent added is 1.5 parts, the adhesion to the substrate and the adhesion to the skin are reduced. At the same time, when the vulcanized product is peeled off for use, some residual adhesive adheres to the skin and the covering release film. Therefore, the addition of reactive anti-aging agents in an amount of 0.1-1.25 parts is more suitable for preparing the adhesive layer of the nipple patch.

[0073] From the comparison of Examples 8 and 9 in Table 2 with Comparative Examples 7 and 8, it can be seen that within a certain range, the reactive anti-aging agents, namely tris(3-trimethoxysilylpropyl)isocyanurate and 1,3,5-tris(trimethoxysilylpropyl)polyisocyanate, after being mixed with the raw materials of silicone gel, basically do not affect the increase in the viscosity of the silicone gel when stored at room temperature for 60 minutes and the cone penetration, i.e., the hardness, after high-temperature vulcanization. At the same time, during the three-month aging process at 60°C, the decrease in viscosity and cone penetration caused by the continued reaction of the rubber material in the adhesive layer of the nipple patch can be effectively suppressed; and the N-containing compounds that directly affect platinum vulcanization, namely γ-aminopropyltriethoxysilane and triazole, after being mixed with the raw materials of silicone gel, the viscosity of the silicone gel after being stored at room temperature for 60 minutes remains basically unchanged, and after being added to the silicone gel formula, it does not vulcanize after the high-temperature stage.

[0074] Although the embodiments disclosed in the present invention are as above, the contents described are only embodiments adopted to facilitate understanding of the present invention and are not intended to limit the present invention. Any technician in the field to which the present invention belongs can make any modifications and changes in the form and details of implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A silicone gel, characterized in that: The composition comprises, by mass, 80 to 90 parts of vinyl silicone oil, 0 to 10 parts of silicone resin, 3 to 50 parts of hydrogen-containing silicone oil, 0.1 to 1.25 parts of an anti-aging agent, 0.1 to 1 parts of a platinum catalyst and 0.001 to 0.01 parts of an inhibitor; Wherein, the molar ratio of hydrogen content / vinyl content is >1; The anti-aging agent is a reactive anti-aging agent, which participates in the reaction during the silicone gel vulcanization process, and the compounds generated after the reaction can affect the activity of the platinum catalyst.

2. The silicone gel according to claim 1, characterized in that: The anti-aging agent is a substance containing an isocyanate group.

3. According to the silicone gel of claim 1, the anti-aging agent comprises one or more of tris(3-trimethoxysilylpropyl)isocyanurate and 1,3,5-tris(trimethoxysilylpropyl)polyisocyanate.

4. The silicone gel according to claim 1, characterized in that: The vinyl silicone oil has a vinyl content of 0.1 to 10 wt % and a viscosity of 100 to 200,000 mPa·s; The vinyl content is preferably 0.1 to 1 wt %.

5. The silicone gel according to claim 1, characterized in that: The silicone resin is vinyl MQ silicone resin; And / or the average molecular weight Mn of the silicone resin is 2000-5000, and the molar ratio of the M / Q group is 0.6-0.9, preferably 0.6-0.

8.

6. The silicone gel according to claim 1, characterized in that: The hydrogen atom content of the hydrogen-containing silicone oil is 0.001-1wt%.

7. The silicone gel according to claim 6, wherein the hydrogen-containing silicone oil is a mixture of terminal methyl side hydrogen-containing silicone oil and terminal hydrogen-containing silicone oil.

8. The silicone gel according to claim 1, characterized in that: The inhibitor is one of 1-ethynyl-1-cyclohexanol, 2-methyl-3-butynyl-2-ol, 3-methyl-1-ethynyl-3-ol or 3,5-dimethyl-1-hexynyl-3-ol or a mixture of more than one thereof.

9. A silicone gel product, characterized in that: The silicone gel product is obtained by coating the silicone gel according to any one of claims 1 to 8 on a substrate and then heating and vulcanizing it.

10. A method for preparing a silicone gel product, characterized in that: The following steps are involved: Vinyl silicone oil, silicone resin, hydrogen-containing silicone oil, inhibitor and anti-aging agent are mixed in proportion, stirred evenly, and a catalyst is added and stirred evenly to obtain silicone gel; The silicone gel is coated on a substrate, heated and vulcanized to obtain the silicone gel product, the heating temperature is 100-150° C., and the vulcanization time is 2-30 minutes.

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