阅读说明：本技术 一种有机硅凝胶及其制备方法 (Organic silicon gel and preparation method thereof ) 是由 郝开强 王聪伟 陶高峰 钱特蒙 陶小乐 何永富 于 2021-08-25 设计创作，主要内容包括：本发明公开了一种有机硅凝胶及其制备方法,有机硅凝胶包含质量比为1:1的A组分与B组分,A组分至少包含如下质量份的组分：端乙烯基硅油：25～80份；端含氢硅油：10～30份；交联氢硅油：0～5份；抑制剂：0.001～0.01份；增粘剂：0.3～1.2份；B组分至少包含如下质量份的组分：乙烯基硅油99～99.99份；铂催化剂：0.01～1份；增粘剂采用增粘剂A、增粘剂B与增粘剂C的一种或多种,所述增粘剂A含有硅氢基,还含有环氧基与烷氧基；所述增粘剂B含有烷氧基、环氧基和至少二个乙烯基,增粘剂C为锆酸酯螯合物,且其活性含量＞70%；有机硅凝胶体系中硅氢基与乙烯基的数量比＞0.85。本申请的硅凝胶不仅具有较高的粘接力,还具有较高的强度。(The invention discloses an organic silicon gel and a preparation method thereof, wherein the organic silicon gel comprises a component A and a component B in a mass ratio of 1:1, and the component A at least comprises the following components in parts by mass: vinyl-terminated silicone oil: 25-80 parts; hydrogen-containing silicone oil end: 10-30 parts; cross-linked hydrogen silicone oil: 0-5 parts; inhibitor (B): 0.001-0.01 part; tackifier: 0.3-1.2 parts; the component B at least comprises the following components in parts by mass: 99-99.99 parts of vinyl silicone oil; platinum catalyst: 0.01-1 part; the tackifier is one or more of a tackifier A, a tackifier B and a tackifier C, wherein the tackifier A contains a hydrosilyl group and also contains an epoxy group and an alkoxy group; the tackifier B contains alkoxy, epoxy and at least two vinyl groups, and the tackifier C is zirconate chelate, and the active content of the tackifier C is more than 70 percent; the ratio of the number of hydrosilation groups to the number of vinyl groups in the silicone gel system is > 0.85. The silicone gel has high bonding force and high strength.)

1. The silicone gel is characterized by comprising a component A and a component B in a mass ratio of 1:1, wherein the component A at least comprises the following components in parts by mass:

vinyl-terminated silicone oil: 25-80 parts;

hydrogen-containing silicone oil end: 10-30 parts;

cross-linked hydrogen silicone oil: 0-5 parts;

inhibitor (B): 0.001-0.01 part;

tackifier: 0.3-1.2 parts;

the component B at least comprises the following components in parts by mass:

99-99.99 parts of vinyl silicone oil;

platinum catalyst: 0.01-1 part;

the tackifier A is one or more of a tackifier A, a tackifier B and a tackifier C, and the tackifier A contains a hydrosilyl group and also contains an epoxy group and an alkoxy group; the tackifier B contains alkoxy, epoxy and at least two vinyl groups, and the tackifier C is zirconate chelate, and the active content of the tackifier C is more than 70 percent; the number ratio of hydrosilation groups to vinyl groups in the organosilicon gel system is more than 0.85.

2. A silicone gel according to claim 1, wherein said tackifier A is one or more of UM-DA71, DT-0231 and DT-0864.

3. The silicone gel of claim 1, wherein said tackifier B is SYL-OFF SL 9250.

4. The silicone gel of claim 1, wherein the tackifier C is one or a combination of Tyzor NPZ and Tyzor NBZ.

5. The silicone gel according to claim 1, wherein the component A further comprises 2 to 20 parts by mass of an MQ resin solution, the MQ resin solution is a mixture of a vinyl-containing methyl MQ resin and a vinyl-terminated silicone oil, the vinyl content of the MQ resin solution is 0.1 to 1mmol/g, and the viscosity is less than or equal to 20000mPa s.

6. The silicone gel of claim 1, wherein the inhibitor is one or more of 2,4,6, 8-tetramethyl-2, 4,6, 8-tetravinyl cyclotetrasiloxane, 1,3, 3-tetramethyl-1, 3-divinylsiloxane, 3-methyl-1-butyn-3-ol, 1-ethynylcyclohexanol, 3-phenyl-1-butyn-3-ol, 3-propyl-1-butyn-3-ol, and 3-octyl-1-butyn-3-ol.

7. The silicone gel according to claim 1, wherein the hydrogen content of the hydrogen-terminated silicone oil is 0.01 to 0.18%, and the mass molar ratio of the hydrosilation groups of the hydrogen-terminated silicone oil to the vinyl groups in the silicone gel is 0.6 to 0.85.

8. The silicone gel of claim 1, wherein the platinum catalyst is one or more of an alcoholic solution of chloroplatinic acid, a tetrahydrofuran complexed platinum catalyst, and a divinyltetramethylsiloxane complexed platinum catalyst.

9. The method of preparing a silicone gel according to any one of claims 1 to 8, comprising the steps of:

preparing a component A: mixing the vinyl-terminated silicone oil, the hydrogen-terminated silicone oil, the cross-linked hydrogen silicone oil, the inhibitor, the MQ resin solution and the tackifier according to the weight ratio, and uniformly dispersing to obtain the water-based oil-based paint;

preparing a component B: mixing the vinyl-terminated silicone oil and the platinum catalyst according to the weight ratio, and uniformly dispersing to obtain the catalyst;

preparing the organic silicon gel: mixing the component A and the component B according to the weight ratio of 1: 1.

Technical Field

The invention relates to the field of organic silicon gel, in particular to organic silicon gel and a preparation method thereof.

Background

The organic silicon gel is an adhesive with higher transparency, and has the performances of dust prevention, water prevention, corrosion prevention and the like, so that the organic silicon gel is widely applied to the field of electronic packaging to ensure the optical performance of the organic silicon gel.

Because the organic silicon gel is an unsaturated crosslinking system, the crosslinking density of the organic silicon gel is low, the flexibility of the organic silicon gel is high, and the problems of insufficient adhesive layer strength and poor shearing resistance exist after the organic silicon gel is cured. In addition, the adhesive force between the adhesive layer and the base material is low, so that the phenomenon of interface damage between the adhesive layer and the base material is easy to occur.

Disclosure of Invention

In order to improve the bonding force and hardness of the organic silicon gel, the application provides the organic silicon gel and the preparation method thereof.

In a first aspect, the present application provides a silicone gel comprising an a component and a B component in a mass ratio of 1:1, the a component comprising at least the following components in parts by mass:

vinyl-terminated silicone oil: 25-80 parts;

hydrogen-containing silicone oil end: 10-30 parts;

cross-linked hydrogen silicone oil: 0-5 parts;

inhibitor (B): 0.001-0.01 part;

tackifier: 0.3-1.2 parts;

the component B at least comprises the following components in parts by mass:

99-99.99 parts of vinyl silicone oil;

platinum catalyst: 0.01-1 part;

the tackifier A is one or more of a tackifier A, a tackifier B and a tackifier C, and the tackifier A contains a hydrosilyl group and also contains an epoxy group and an alkoxy group; the tackifier B contains alkoxy, epoxy and at least two vinyl groups, and the tackifier C is zirconate chelate, and the active content of the tackifier C is more than 70 percent; the number ratio of hydrosilation groups to vinyl groups in the organosilicon gel system is more than 0.85.

By adopting the technical scheme, the quantity ratio of the hydrosilyl to the vinyl is more than 85% by controlling the proportion of the raw materials, and meanwhile, the tackifier is adopted to be matched together, so that the adhesive force of the silicone gel can be improved, the strength of the silicone gel after curing can be enhanced, and the silicone gel can be ensured to have better curing speed.

It should be noted that the number of hydrosilation groups in the silicone gel system is smaller than the number of vinyl groups, and an unsaturated crosslinking system is formed by crosslinking the hydrosilation groups with the vinyl groups. When the number ratio of hydrosilyl groups to vinyl groups (H/Vi ratio) is more than 0.85, the crosslinking density of the silicone gel system can be obviously improved, but the bonding force of the silicone gel system and a substrate is reduced. By adopting the three tackifiers, the adhesive force between the silicone gel and the base material can be obviously improved.

The action mechanism for realizing the tackifying and improving the hardness may be that the tackifier A contains more hydrosilyl groups and can provide sufficient hydrosilyl groups for a system, so that the crosslinking density is improved, and the hardness of a silica gel layer is finally enhanced. Meanwhile, the adhesion promoter contains active groups such as epoxy groups, alkoxy groups and the like, and can be in reactive association with the active groups on the surface of the base material under the action of a platinum catalyst, so that the adhesive force of the silicone gel and the base material is improved. In addition, when the hydrosilyl group in the tackifier is enough to ensure that the H/Vi ratio is more than 0.85, no crosslinking hydrosilicone oil needs to be added into the system. For the tackifier B, the tackifier B needs to be matched with the cross-linked hydrogen silicone oil, so that the H/Vi ratio in the system is more than 0.85, and the aim of improving the hardness is fulfilled. And the contained vinyl group is utilized to be in crosslinking association with the hydrosilyl in the system; the alkoxy and epoxy groups contained in the adhesive are associated with active groups on the surface of a base material to form an interface connection effect, so that the adhesive force is improved. For the tackifier C, the tackifier C needs to be matched with the cross-linked hydrogen silicone oil, so that the H/Vi ratio in a system is more than 0.7, and the H/Vi ratio is preferably more than 0.85, and the aim of improving the hardness is fulfilled; and it achieves the purpose of adhesion promotion through coupling.

The vinyl-terminated silicone oil in the application is polydimethylsiloxane with vinyl at two ends, the viscosity is 1-20000 mPa.s, one kind of vinyl-terminated silicone oil with the viscosity can be independently used, and the vinyl-terminated silicone oils with different viscosities can be compounded for use so as to adjust the viscosity to be proper. Cross-linked hydrogen silicone oil

The cross-linked hydrogen silicone oil can be singly cross-linked hydrogen silicone oil with one hydrogen content or compounded by a plurality of cross-linked hydrogen silicone oils, and the aim of improving the hardness of the silicon gel can be achieved only by meeting the requirement that the ratio of the number of the hydrosilates to the number of the vinyls (H/Vi ratio) in the silicon gel system is 0.85-1. In addition, the cross-linked hydrosilicon oil usually contains at least 3 hydrosilyl groups in the molecule, and the hydrogen content is higher, and the hydrogen content refers to the mass fraction of the hydrogen of the hydrosilyl groups in the molecule. The molecular mechanism of the cross-linked hydrogen silicone oil comprises the following chemical formulas 1-3.

Chemical formula 1, structural formula I of cross-linked hydrogen silicone oil;

chemical formula 2, cross-linked hydrogen silicone oil structural formula II;

chemical formula 3, structural formula III of crosslinked hydrogen silicone oil;

wherein in chemical formula 1, n is an integer not less than 0, and m is an integer not less than 1; in the chemical formula 2, x is an integer of 1 or more, and y is an integer of 3 or more.

Preferably, the tackifier A is one or more of UM-DA71, DT-0231 and DT-0864.

By adopting the technical scheme, the UM-DA71, DT-0231 and DT-0864 molecules contain more hydrosilyl groups, and can be used as a crosslinking agent to crosslink with vinyl in a system to promote the formation of gel; and because the epoxy group and the alkoxy group are contained, the epoxy group and the alkoxy group can react with active groups on the interface of the base material to enhance the bonding effect.

The above UM-DA71 is obtained from Wuhan Arecaceae; DT-0231 and DT-0864 were obtained from Deltay silicone, Guangzhou.

Preferably, the tackifier B is SYL-OFF SL 9250.

By adopting the technical scheme, SYL-OFF SL9250 is obtained from Dow Corning, the molecule of the SYL-OFF SL9250 contains alkoxy, epoxy and polyvinyl, and the plurality of vinyl enables the tackifier to have more crosslinking sites and can form more tight connection with hydrosilyl in a system; the alkoxy and the epoxy can be bonded with the active group on the surface of the base material, and the alkoxy and the epoxy form excellent adhesion.

Preferably, the tackifier C is usedAndor a combination thereof.

By adopting the technical scheme, the two zirconate chelates are n-propyl zirconate, the active contents of the two zirconate chelates are more than 70%, the two zirconate chelates have high hydrolytic stability and good coupling effect, the curing speed can be accelerated by adding the silicon gel system, and the transparency of the silicon gel is not influenced.

Preferably, the component A also comprises 2-20 parts of MQ resin solution, the MQ resin solution is a mixture of methyl MQ resin containing vinyl and vinyl-terminated silicone oil, and the viscosity of the MQ resin solution is less than or equal to 20000 mPa.

By adopting the technical scheme, the MQ resin has a body structure and contains certain functional vinyl, can be used for adjusting the H/Vi ratio in a system, and is finally beneficial to improving the hardness of a silicone gel system.

Preferably, the inhibitor is one or more of 2,4,6, 8-tetramethyl-2, 4,6, 8-tetravinyl cyclotetrasiloxane, 1,3, 3-tetramethyl-1, 3-divinyl siloxane, 3-methyl-1-butyn-3-ol, 1-ethynylcyclohexanol, 3-phenyl-1-butyn-3-ol, 3-propyl-1-butyn-3-ol and 3-octyl-1-butyn-3-ol.

By adopting the technical scheme, the inhibitor has the function of regulating the curing speed of the silicone gel, and the mechanism is that the inhibition of the platinum catalyst is realized to inhibit the crosslinking reaction, so that the crosslinking curing process is controlled.

Preferably, the hydrogen content of the hydrogen-terminated silicone oil is 0.01-0.18%, and the mass molar ratio of the hydrosilation of the hydrogen-terminated silicone oil to the vinyl in the silicone gel is 0.6-0.85.

By adopting the technical scheme, the terminal hydrogen-containing silicone oil is usually polydimethylsiloxane (shown in chemical formula 4) with hydrosilyl groups at two ends, and the main function of the terminal hydrogen-containing silicone oil is to extend the chain of the terminal vinyl silicone oil, so that the colloid has higher adhesive force and flexibility.

Chemical formula 4, structural formula of terminal hydrogen-containing silicone oil;

preferably, the platinum catalyst is one or more of alcohol solution of chloroplatinic acid, platinum catalyst coordinated with tetrahydrofuran and platinum catalyst coordinated with divinyltetramethylsiloxane.

By adopting the technical scheme, the catalyst can effectively promote the hydrosilylation and vinyl addition reaction, and the curing speed is increased.

In a second aspect, the present application provides a method of preparing a silicone gel comprising the steps of:

preparing a component A: mixing the vinyl-terminated silicone oil, the hydrogen-terminated silicone oil, the cross-linked hydrogen silicone oil, the inhibitor and the tackifier according to a ratio, and uniformly dispersing to obtain the water-based paint;

preparing a component B: mixing the vinyl-terminated silicone oil and the platinum catalyst according to a ratio, and uniformly dispersing to obtain the catalyst;

preparing the organic silicon gel: mixing the component A and the component B according to the weight ratio of 1: 1.

The A component and the B component of the organic silicon gel need to be stored separately before use, and when the organic silicon gel is used, after the A component and the B component are mixed, the catalyst in the B component is utilized to catalyze and promote the crosslinking and curing.

In summary, the present application has the following beneficial effects:

1. according to the application, the ratio of hydrosilation to vinyl in the silicon gel system is controlled to be 0.85-1, so that the crosslinking density of the silicon gel is effectively improved, and the strength of the cured silicon gel is increased; and the viscosity reduction caused by the increase of the crosslinking density is compensated by adding the specific tackifier, and the problem of weak bonding force between the tackifier and the base material is effectively solved.

2. According to the application, the tackifier containing a large amount of hydrosilyl groups is adopted, the hydrosilyl content in a system is provided, the increase of the crosslinking density and the hardness is promoted, and meanwhile, the reactive groups contained in the tackifier react and bond with the interface of the base material, so that the bonding force between the silicone gel and the base material is enhanced.

Examples

Example 1, a silicone gel, the selection of the raw material components are shown in table 1 and was prepared as follows:

preparing a component A: adding vinyl-terminated silicone oil, hydrogen-terminated silicone oil, cross-linked hydrogen silicone oil, inhibitor and tackifier into a planetary mixer according to a ratio, and mixing for 30min to obtain the final product;

preparing a component B: adding the vinyl-terminated silicone oil and the platinum catalyst into a planetary stirrer according to the proportion for mixing for 30min to obtain the catalyst;

preparing the organic silicon gel: mixing the component A and the component B according to the weight ratio of 1: 1.

Examples 2 to 5, a silicone gel, were different from example 1 in that the selection of the raw material components was as shown in table 1.

Raw material selection and dosage (kg) of the silicone gels in Table 1 and examples 1-5

Examples 6 to 9, a silicone gel, were different from example 1 in that the selection of each raw material component was as shown in table 2.

Raw material selection and dosage (kg) of the silicone gels in Table 2 and examples 6-9

In tables 1 and 2, a vinyl-terminated silicone oil having a vinyl content of 0.1185mmol/g was obtained from Anbia; the vinyl-terminated silicone oil having a vinyl content of 0.057mmol/g was obtained from Anbia; 0.17% of cross-linked hydrogen silicone oil was obtained from Huazhi moist silicone; the terminal hydrogen-containing silicone oil with 0.07 percent of hydrogen content is obtained from lubricating organic silicon; the MQ resin solution with the vinyl content of 0.722mmol/g is obtained from the organic silicon of wheat-rice-moistening; the MQ resin solution with the vinyl content of 0.485mmol/g is obtained from the organic silicon of lubricating rice; crosslinked hydrogen silicone oil having a hydrogen content of 0.11% was obtained from ambia; the platinum catalyst was obtained from heili using a vinyl tetramethylsiloxane coordinated platinum catalyst.

The raw materials can be obtained from different manufacturers, and only the required parameter indexes are required to be met.

Comparative example

Comparative example 1, a silicone gel, differs from example 6 in that the selection of the raw material components is shown in table 3 and the H/Vi ratio in the silicone gel system is 0.81.

Comparative example 2, a silicone gel, differs from example 1 in that the selection of the raw material components is shown in table 3, and no tackifier is added to the a component.

Raw material selection and application rates (kg) of the silicone gels in Table 3 and comparative examples 1 to 2

Performance test

Silicone gel performance testing:

the test method comprises the following steps: (1) testing the cone penetration of the silica gel according to the regulations and standards in GB/T269; wherein, the cone adopts 1/4 proportional cone.

(2) The samples were prepared and tested according to the specifications and standards of GB/T7124, in which glass was used as the substrate, and two glass substrates were bonded with silicone gel at a bond line thickness of 0.2mm and a drawing speed of 100 mm/min.

(3) The refractive index was measured according to the provisions and standards of GB/T614 and using an Abbe refractometer.

The test results of the above test are shown in Table 4.

TABLE 4 organosilicon Performance test results

And (3) analyzing test results:

(1) by combining examples 1-9 and comparative examples 1-2 and combining table 4, it can be seen that the strength of the silicone gel is effectively improved while the adhesive property of the silicone gel is improved by controlling the ratio of the hydrosilyl group to the vinyl group in the system to be 0.85-1 and combining with a tackifier. The principle of the method is that the cross-linking density of a silica gel system can be remarkably improved by controlling the ratio of H/Vi to be 0.85-1, so that the hardness of the silica gel system is improved. The viscosity of the silicone gel is reduced while the crosslinking density is increased, and the silicone gel is crosslinked and associated with vinyl or hydrosilyl in a silicone gel system by adding the tackifier by utilizing hydrosilyl or vinyl contained in the tackifier; on the other hand, the active groups on the surface of the substrate are bonded by the epoxy groups and the alkoxy groups contained in the thickener, thereby improving the interfacial adhesion between the silicone gel and the substrate. Finally, the use requirement of hardness and stickiness is met.

The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.