Vinyl MQ resin, preparation method and release agent

Abstract

The invention discloses a method for improving the end-capping rate of vinyl MQ resin by improving a two-step end-capping process, the vinyl MQ resin is generated by a component A) high-hydroxyl MQ resin, a component B) organic silicon vinyl double-end-capping agent and a component C) five-membered ring or six-membered ring polar small molecule compound containing single heteroatoms (oxygen, sulfur and nitrogen), and compared with a reaction system without the component C), the end-capping rate of the vinyl MQ resin is improved. The introduction of a five-membered ring or six-membered ring polar small molecule compound containing a single heteroatom in the component C) can obviously improve the blocking rate of the high hydroxyl MQ resin. The obtained MQ resin with high vinyl content is applied to a formula of a heavy stripping force control agent of a release agent, provides high and stable release force for a release material, and can be applied to a system needing relatively high release force.

Description

Technical Field

[0001] The invention relates to a method for improving the end-capping efficiency of a vinyl MQ resin, a prepared vinyl MQ resin and application thereof. Background Art

[0002] Release agent is an important component of pressure-sensitive adhesive products. It is used between the substrate and the pressure-sensitive adhesive layer. Its main function is to protect the pressure-sensitive adhesive layer coated on the substrate to prevent the pressure-sensitive adhesive layer from being contaminated or sticking to other objects and becoming ineffective. With the increasing application of pressure-sensitive adhesives, higher requirements are placed on the various properties of release materials. Among them, release force is one of the key performance indicators of release agents. Under specific conditions, at a certain peeling angle and peeling speed, the value measured by bonding the release material with a standard test tape is the release force of the release material. Silicone release agents are commonly composed of five components: main agent, cross-linking agent, anchoring agent, release force controller, and catalyst. The release force controller mainly includes two types: heavy release force controller and light release force controller. Its main function is to adjust the release force of the release agent. Heavy release force controller can help the release agent achieve a higher release force value and maintain long-term stability. These advantages make it indispensable in the tape, protective film and electronic die-cutting industries. MQ resins with high vinyl content can be used in the formulation of heavy release force controllers to provide higher and more stable release force for release agents.

[0003] At present, the main methods for producing vinyl MQ silicone resins are sodium silicate method and silicate method. The synthesis process is relatively complicated, the vinyl content of the obtained vinyl MQ silicone resin is relatively low, the vinyl content is not easy to control, and the post-processing is complicated. U.S. Patent US2016326320A1 discloses a method for using a halogenated silane end-capping agent to perform two-step end-capping on a high-hydroxy MQ resin to obtain a vinyl MQ resin. The halogenated silane end-capping agent used in this method, such as vinyl dimethyl chlorosilane, has a high end-capping activity, and no catalyst is required during the reaction. However, hydrochloric acid is produced during the reaction, and the product needs to be washed with water, producing acidic wastewater that is difficult to treat. Chinese patent CN102718971A discloses a method for using a non-halogenated silane end-capping agent to perform two-step end-capping on a high-hydroxy MQ resin to obtain a vinyl MQ resin. This method requires the use of an appropriate amount of acidic catalyst, and the acidic substance treatment method left after the reaction is simple.

[0004] Therefore, how to further effectively improve the end-capping rate of high-hydroxyl MQ resin and provide a higher and more stable release force for the release material is an urgent problem to be solved. Summary of the invention

[0005] In view of this, the present invention studies the process of preparing vinyl MQ resin by modifying high hydroxyl MQ resin, provides a capping method with high vinyl content and easy to control, and then applies the prepared vinyl MQ resin with high vinyl content to the formulation of the release agent to provide the release material with higher and more stable release force.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] In one aspect, the present invention provides a method for preparing a vinyl MQ resin, the method comprising the following steps:

[0008] 1) adding a solvent to the high hydroxyl MQ silicone resin and stirring thoroughly at room temperature until the silicone resin is dissolved;

[0009] 2) adding a capping agent, a catalyst A, and a polar small molecule compound having a five-membered ring or a six-membered ring containing a single heteroatom as an auxiliary agent, and heating the reaction;

[0010] 3) adding alkaline inorganic salt powder and stirring to carry out neutralization reaction;

[0011] 4) After standing, filtering and evaporating, vinyl MQ resin is obtained.

[0012] In the present invention, the high hydroxyl MQ type silicone resin in step 1) has the formula: (R 3 SiO 1 / 2 ) m (SiO 4 / 2 ) n , wherein R is hydrogen or methyl, the m / n molar ratio is 0.7 to 0.9, the (OH) group content is between 2.6 and 3.5 wt %, the weight average molecular weight is between 16,000 and 20,000 g / mol, and the molecular weight distribution coefficient is less than 2.0. Preferably, the (OH) group content is between 2.65 and 2.98 wt %, the weight average molecular weight is between 16,000 and 19,000 g / mol, and the molecular weight distribution coefficient is between 1.58 and 1.70.

[0013] In the present invention, the solvent in step 1) is selected from one or more of naphtha, toluene and xylene, preferably xylene.

[0014] In the present invention, the mass ratio of high hydroxyl MQ silicone resin to solvent in step 1) is 7-5:4-1.25;

[0015] In the present invention, the end-capping agent in step 2) is selected from one or more of tetramethyldivinyldisiloxane and dimethylvinylethoxysilane, preferably tetramethyldivinyldisiloxane; the catalyst A is selected from one or more of trifluoroacetic acid, trifluoromethanesulfonic acid, HCl, and HBr, preferably trifluoromethanesulfonic acid;

[0016] In the present invention, the five-membered or six-membered polar small molecule compound containing a single heteroatom in step 2) is selected from one or more of dihydrofuran, thiophene, tetrahydrothiophene, pyrrole, tetrahydropyrrole, and pyridine, preferably thiophene. The structural formula is as follows:

[0017]

[0018] In the present invention, in step 2), the amount of the end-capping agent added is 10 to 20 parts, preferably 14 to 20 parts, relative to 100 parts of high hydroxyl MQ silicone resin; the amount of catalyst A added is 0.2 to 1 part, preferably 0.2 to 0.6 parts; and the amount of the auxiliary agent added is 0.5 to 10% of the mass of the high hydroxyl silicone resin solution.

[0019] In the present invention, the temperature of the temperature-raising reaction in step 2) is 50-100° C., and the reaction time is 2-8 hours; preferably, the reaction temperature is 60-90° C., and the reaction time is 3-5 hours.

[0020] In the present invention, the alkaline inorganic salt in step 3) is selected from any one of calcium carbonate, sodium bicarbonate or sodium carbonate, preferably calcium carbonate; the added mass of the alkaline inorganic salt is 5 to 10 times that of the acid catalyst, preferably 3 to 5 times. The neutralization reaction time is 0.5 to 3 hours, preferably 0.5 to 1.5 hours.

[0021] In the present invention, the process of standing, filtering and evaporating in step 4) is not particularly limited, as long as the solvent and impurities in the vinyl MQ resin product can be removed.

[0022] In a second aspect, the present invention also provides a vinyl MQ resin prepared by the above method.

[0023] On the other hand, the present invention further provides a release agent, which comprises, in parts by mass:

[0024] 100 parts of vinyl silicone oil A;

[0025] 15 to 30 parts of a peel force control agent;

[0026] 1 to 9 parts of a cross-linking agent;

[0027] 1 to 9 parts of catalyst B;

[0028] The release force control agent comprises, in parts by mass:

[0029] 50-70 parts of vinyl MQ resin;

[0030] Vinyl silicone oil B 10-30 parts;

[0031] 20 to 30 parts of hydrocarbon solvent.

[0032] In the present invention, the release force control agent of the release material is obtained by mixing the vinyl MQ resin, the vinyl silicone oil B and the long-chain hydrocarbon solvent in proportion to form a clear and transparent liquid.

[0033] In the present invention, the viscosity of the vinyl silicone oil B is 30000-60000 mPa·s, preferably 50000-60000 mPa·s, and the vinyl content is 0.05-0.15 wt%, preferably 0.08-0.10 wt%; the hydrocarbon solvent is selected from long-chain olefins with 8 to 19 carbon atoms, preferably long-chain olefins with 10 to 15 carbon atoms.

[0034] In the present invention, the viscosity of the vinyl silicone oil A is 200-800 mPa·s, and the vinyl content is 0.5-1.5 wt %; preferably, the viscosity of the vinyl silicone oil A is 300-500 mPa·s, and the vinyl content is 0.8-1.2 wt %.

[0035] In the present invention, the crosslinking agent is a pendant hydrogen-containing silicone oil with a viscosity of 10 to 100 mPa·s and a hydrogen mass fraction of 1.0 to 2.0 wt %; preferably, the viscosity is 50 to 80 mPa·s and the hydrogen mass fraction is 0.5 to 1.5 wt %.

[0036] In the present invention, the catalyst B is a platinum catalyst, which contains platinum at a concentration of 1000 to 5000 ppm; preferably a karstedt catalyst, which contains platinum at a concentration of 3000 to 5000 ppm.

[0037] In the present invention, the mass ratio of the vinyl silicone oil A, the release force control agent, the crosslinking agent and the catalyst B is: 100: (15-30): (2-5): (1-5).

[0038] In the present invention, the method for preparing the release agent comprises the following steps: uniformly mixing the vinyl silicone oil and the release force control agent, and then adding a crosslinking agent and a catalyst to prepare the release agent.

[0039] The beneficial effects of the present invention are:

[0040] The present invention effectively improves the end-capping efficiency of high-hydroxyl MQ resin by introducing a five-membered ring or six-membered ring polar small molecule compound containing a single heteroatom as an auxiliary agent, and the vinyl content of the obtained silicone resin is significantly increased. The prepared high-vinyl content vinyl MQ resin is applied to the formulation of the release agent, providing the release agent with a higher and more stable release force. DETAILED DESCRIPTION

[0041] In order to further illustrate the present invention, the preferred embodiments of the present invention are described below in conjunction with specific embodiments. However, it should be pointed out and understood that these specific embodiments are only for further illustrating the features and methods of the present invention, rather than limiting the present invention.

[0042] Raw materials and sources:

[0043] High hydroxyl MQ resin: prepared by referring to the method disclosed in Example 3 of patent CN114230795A, with an (OH) group content of 2.6 wt%.

[0044] Naphtha: ≥99%, Guangdong Wengjiang Chemical Reagent Co., Ltd.

[0045] Toluene: analytical grade AR, Beijing Inokai Technology Co., Ltd.

[0046] Xylene: ≥99.5%, Sinopec Qingdao Refining and Chemical Company

[0047] Trifluoromethanesulfonic acid: ≥98%, aladdin

[0048] Trifluoroacetic acid: ≥98%, aladdin

[0049] HCl: analytical grade AR, Beijing Inokai Technology Co., Ltd.

[0050] HBr:>99%, Shanghai Reference Pharmaceutical Technology Co., Ltd.

[0051] Tetramethyldivinyldisiloxane:>96%, Beijing Inokai Technology Co., Ltd.

[0052] Dimethylvinylethoxysilane: >97%, Shanghai Mairui Biochemical Technology Co., Ltd.

[0053] 1-Decene: >98%, Shanghai MacLean Biochemical Technology Co., Ltd.

[0054] 1-Tridecene: >97%, Anhui Zesheng Technology Co., Ltd.

[0055] 1-Pentadecene:>99%, Henan Evonik Biotechnology Co., Ltd.

[0056] Vinyl silicone oil: Ningbo Runhe High-tech Materials Technology Co., Ltd.

[0057] Crosslinking agent: Ningbo Runhe High-tech Materials Technology Co., Ltd.

[0058] karstedt catalysts: Heraeus Precious Metals

[0059] Example 1

[0060] S1 Add 500g of high hydroxyl MQ silicone resin (hydroxyl content 2.65wt%, weight average molecular weight 16000g / mol, molecular weight distribution coefficient 1.58) and 125g of naphtha to a three-necked flask equipped with a stirrer, a thermometer and a condenser, and stir at room temperature until the high hydroxyl MQ silicone resin is completely dissolved. Add 100g of dimethylvinylethoxysilane, 3g of trifluoroacetic acid and 3.125g of dihydrofuran, heat to 60°C, stir and react for 5 hours, stop heating, add 10g of sodium carbonate, neutralize, stir for 0.5 hours, stop stirring, let stand, and filter with a positive pressure filter. Finally, transfer the filtrate to a flask, evaporate the low-boiling substances under reduced pressure, and obtain a white powdery solid, which is dissolved in deuterated chloroform, dimethyl terephthalate as the internal standard, and the vinyl content is 1.81wt% determined by 1HNMR; the weight average molecular weight is 15900g / mol and the molecular weight distribution coefficient is 1.58 determined by GPC.

[0061] S2: 70g of vinyl MQ resin, 10g of vinyl silicone oil and 20g of 1-decene are mixed and stirred to form a clear and transparent liquid, which is the peeling force control agent. The viscosity of the vinyl silicone oil is 60000mPa·s and the vinyl content is 0.10wt%. The vinyl content of the peeling force control agent is 3.93wt% and the viscosity is 491mPa·s.

[0062] S3: After 100g of vinyl silicone oil and 30g of peeling force control agent are evenly mixed, 5g of cross-linking agent and 5g of catalyst are added to prepare a release agent, wherein the vinyl silicone oil has a viscosity of 500mPa·s and a vinyl content of 1.2wt%; the cross-linking agent is a pendant hydrogen-containing silicone oil with a viscosity of 80mPa·s and a hydrogen mass fraction of 1.9wt%; the catalyst is a karstedt catalyst, and the platinum concentration contained in it is 5000ppm.

[0063] Example 2

[0064] S1 Add 500g of high hydroxyl MQ silicone resin (hydroxyl content 2.65wt%, weight average molecular weight 16000g / mol, molecular weight distribution coefficient 1.64) and 125g of toluene to a three-necked flask equipped with a stirrer, a thermometer and a condenser, and stir at room temperature until the high hydroxyl MQ silicone resin is completely dissolved. Add 100g of tetramethyl divinyl disiloxane, 3g of HBr and 6.25g of thiophene, heat to 60°C, stir and react for 4 hours, stop heating, add 10g of sodium bicarbonate, neutralize, stir for 1 hour, stop stirring, let stand, and filter with a positive pressure filter. Finally, transfer the filtrate to a flask, evaporate the low boiling point under reduced pressure, and obtain a white powdery solid, which is dissolved in deuterated chloroform, dimethyl terephthalate as the internal standard, and the vinyl content is 2.01wt% determined by 1H NMR; the weight average molecular weight is 16200g / mol and the molecular weight distribution coefficient is 1.62 determined by GPC.

[0065] S2: 70g of vinyl MQ resin, 10g of vinyl silicone oil and 20g of 1-1-tridecene are mixed and stirred to form a clear and transparent liquid, which is the peeling force control agent. The viscosity of the vinyl silicone oil is 55000mPa·s and the vinyl content is 0.10wt%. The vinyl content of the peeling force control agent is 4.14wt% and the viscosity is 502mPa·s.

[0066] S3: After 100g of vinyl silicone oil and 30g of peeling force control agent are evenly mixed, 5g of cross-linking agent and 5g of catalyst are added to prepare a release agent, wherein the vinyl silicone oil has a viscosity of 400mPa·s and a vinyl content of 1.2wt%; the cross-linking agent is a pendant hydrogen-containing silicone oil with a viscosity of 80mPa·s and a hydrogen mass fraction of 1.9wt%; the catalyst is a karstedt catalyst, and the platinum concentration contained in it is 5000ppm.

[0067] Example 3

[0068] S1 Add 600g of high hydroxyl MQ silicone resin (hydroxyl content 2.76wt%, weight average molecular weight 16800g / mol, molecular weight distribution coefficient 1.63) and 257.14g of xylene to a three-necked flask equipped with a stirrer, a thermometer and a condenser, and stir at room temperature until the high hydroxyl MQ silicone resin is completely dissolved. Add 85.12g of tetramethyl divinyl disiloxane, 1g of trifluoromethanesulfonic acid and 17.14g of pyrrole, heat to 90°C, stir and react for 3.5 hours, stop heating, add 5g of calcium carbonate, neutralize, stir for 1 hour, stop stirring, let stand, and filter with a positive pressure filter. Finally, transfer the filtrate to a flask, evaporate the low-boiling substances under reduced pressure, and obtain a white powdery solid, which is dissolved in deuterated chloroform, with dimethyl terephthalate as the internal standard, and the vinyl content is 2.14wt% determined by 1H NMR; the weight average molecular weight is 16500g / mol and the molecular weight distribution coefficient is 1.62 determined by GPC.

[0069] S2: 60g of vinyl MQ resin, 20g of vinyl silicone oil and 25g of 1-pentadecene are mixed and stirred to form a clear and transparent liquid, which is the peeling force control agent. The vinyl silicone oil has a viscosity of 50000mPa·s and a vinyl content of 0.09wt%. The vinyl content of the peeling force control agent is 4.25wt% and the viscosity is 508mPa·s.

[0070] S3: 100g of vinyl silicone oil and 15g of release force control agent are mixed evenly, and then 4g of cross-linking agent and 4g of catalyst are added to prepare a release agent, wherein the vinyl silicone oil has a viscosity of 300mPa·s and a vinyl content of 1.0wt%; the cross-linking agent is a pendant hydrogen-containing silicone oil with a viscosity of 60mPa·s and a hydrogen mass fraction of 1.7wt%; the catalyst is a karstedt catalyst, and the platinum concentration contained in it is 5000ppm.

[0071] Example 4

[0072] S1: Add 500g of high-hydroxyl MQ silicone resin (hydroxyl content 2.98wt%, weight average molecular weight 19000g / mol, molecular weight distribution coefficient 1.68) and 214.29g of xylene to a three-necked flask equipped with a stirrer, a thermometer and a condenser, and stir at room temperature until the high-hydroxyl MQ silicone resin is completely dissolved. Add 81.06g of 1,3-tetramethyldivinyldisiloxane, 2.5g of trifluoromethanesulfonic acid and 28.57g of thiophene, heat to 80°C, stir and react for 3 hours, stop heating, add 7.85g of calcium carbonate, neutralize, stir for 1 hour, stop stirring, let stand, and filter with a positive pressure filter. Finally, the filtrate was transferred to a flask, and low-boiling products were evaporated under reduced pressure to obtain a white powdery solid, which was dissolved in deuterated chloroform with dimethyl terephthalate as the internal standard. The vinyl content was determined by 1H NMR to be 2.25 wt %; the weight average molecular weight was determined by GPC to be 18870 g / mol, and the molecular weight distribution coefficient was 1.67.

[0073] S2: 60g of vinyl MQ resin, 20g of vinyl silicone oil and 30g of 1-1-tridecene are mixed and stirred to form a clear and transparent liquid, which is the peeling force control agent. The vinyl silicone oil has a viscosity of 50000mPa·s and a vinyl content of 0.08wt%. The vinyl content of the peeling force control agent is 4.36wt% and the viscosity is 542mPa·s.

[0074] S3: After 100g of vinyl silicone oil and 20g of release force control agent are mixed evenly, 3g of cross-linking agent and 3g of catalyst are added to prepare a release agent, wherein the vinyl silicone oil has a viscosity of 300mPa·s and a vinyl content of 0.8wt%; the cross-linking agent is a pendant hydrogen-containing silicone oil with a viscosity of 50mPa·s and a hydrogen mass fraction of 1.5wt%; the catalyst is a karstedt catalyst, and the platinum concentration contained in it is 4000ppm.

[0075] Example 5

[0076] S1: Add 500g of high-hydroxyl MQ silicone resin (hydroxyl content 2.98wt%, weight average molecular weight 19000g / mol, molecular weight distribution coefficient 1.66) and 214.29g of xylene to a three-necked flask equipped with a stirrer, a thermometer and a condenser, and stir at room temperature until the high-hydroxyl MQ silicone resin is completely dissolved. Add 71.12g of tetramethyl divinyl disiloxane, 2.5g of trifluoromethanesulfonic acid and 42.86g of thiophene, heat to 80°C, stir and react for 3 hours, stop heating, add 7.85g of calcium carbonate, neutralize, stir for 1 hour, stop stirring, let stand, and filter with a positive pressure filter. Finally, the filtrate was transferred to a flask, and the low-boiling products were evaporated under reduced pressure to obtain a white powdery solid, which was dissolved in deuterated chloroform with dimethyl terephthalate as the internal standard. The vinyl content was determined by 1HNMR to be 2.38 wt %; the weight average molecular weight was determined by GPC to be 19110 g / mol, and the molecular weight distribution coefficient was 1.68.

[0077] S2: 50g of vinyl MQ resin, 30g of vinyl silicone oil and 20g of 1-1-tridecene are mixed and stirred to form a clear and transparent liquid, which is the peeling force control agent. The vinyl silicone oil has a viscosity of 50000mPa·s and a vinyl content of 0.08wt%. The vinyl content of the peeling force control agent is 4.50wt% and the viscosity is 546mPa·s.

[0078] S3: After 100g of vinyl silicone oil and 20g of release force control agent are mixed evenly, 2g of cross-linking agent and 3g of catalyst are added to prepare a release agent, wherein the vinyl silicone oil has a viscosity of 300mPa·s and a vinyl content of 0.8wt%; the cross-linking agent is a pendant hydrogen-containing silicone oil with a viscosity of 50mPa·s and a hydrogen mass fraction of 1.5wt%; the catalyst is a karstedt catalyst, and the platinum concentration contained in it is 3000ppm.

[0079] Example 6

[0080] S1: Add 500g of high-hydroxyl MQ silicone resin (hydroxyl content 2.98wt%, weight average molecular weight 19000g / mol, molecular weight distribution coefficient 1.70) and 214.29g of xylene to a three-necked flask equipped with a stirrer, a thermometer and a condenser, and stir at room temperature until the high-hydroxyl MQ silicone resin is completely dissolved. Add 71.12g of tetramethyl divinyl disiloxane, 2.5g of trifluoromethanesulfonic acid and 57.14g of thiophene, heat to 80°C, stir and react for 3 hours, stop heating, add 7.85g of calcium carbonate, neutralize, stir for 1 hour, stop stirring, let stand, and filter with a positive pressure filter. Finally, the filtrate was transferred to a flask, and the low-boiling products were evaporated under reduced pressure to obtain a white powdery solid, which was dissolved in deuterated chloroform with dimethyl terephthalate as the internal standard. The vinyl content was determined to be 2.40 wt% by 1HNMR; the weight-average molecular weight was determined to be 18500 g / mol by GPC, and the molecular weight distribution coefficient was 1.71.

[0081] S2: 50g of vinyl MQ resin, 30g of vinyl silicone oil and 20g of 1-1-tridecene are mixed and stirred to form a clear and transparent liquid, which is the peeling force control agent. The vinyl silicone oil has a viscosity of 50000mPa·s and a vinyl content of 0.08wt%. The vinyl content of the peeling force control agent is 4.55wt% and the viscosity is 549mPa·s.

[0082] S3: After 100g of vinyl silicone oil and 20g of release force control agent are mixed evenly, 2g of cross-linking agent and 3g of catalyst are added to prepare a release agent, wherein the vinyl silicone oil has a viscosity of 300mPa·s and a vinyl content of 0.8wt%; the cross-linking agent is a pendant hydrogen-containing silicone oil with a viscosity of 50mPa·s and a hydrogen mass fraction of 1.5wt%; the catalyst is a karstedt catalyst, and the platinum concentration contained in it is 3000ppm.

[0083] Example 7

[0084] S1 Add 700g of high hydroxyl MQ silicone resin (hydroxyl content 2.98wt%, weight average molecular weight 19000g / mol, molecular weight distribution coefficient 1.69) and 400g of xylene to a three-necked flask equipped with a stirrer, a thermometer and a condenser, and stir at room temperature until the high hydroxyl MQ silicone resin is completely dissolved. Add 100g of tetramethyl divinyl disiloxane, 3g of trifluoromethanesulfonic acid and 110g of thiophene, heat to 80°C, stir and react for 3 hours, stop heating, add 10g of calcium carbonate, neutralize, stir for 1.5 hours, stop stirring, let stand, and filter with a positive pressure filter. Finally, transfer the filtrate to a flask, evaporate the low-boiling substances under reduced pressure, and obtain a white powdery solid, which is dissolved in deuterated chloroform, dimethyl terephthalate as the internal standard, and the vinyl content is 2.41wt% determined by 1HNMR; the weight average molecular weight is 18980g / mol and the molecular weight distribution coefficient is 1.67 determined by GPC.

[0085] S2: 50g of vinyl MQ resin, 30g of vinyl silicone oil and 20g of 1-1-tridecene are mixed and stirred to form a clear and transparent liquid, which is the peeling force control agent. The viscosity of the vinyl silicone oil is 50000mPa·s and the vinyl content is 0.08wt%. The vinyl content of the peeling force control agent is 4.57wt% and the viscosity is 547mPa·s.

[0086] S3: After 100g of vinyl silicone oil and 20g of release force control agent are mixed evenly, 2g of cross-linking agent and 3g of catalyst are added to prepare a release agent, wherein the vinyl silicone oil has a viscosity of 300mPa·s and a vinyl content of 0.8wt%; the cross-linking agent is a pendant hydrogen-containing silicone oil with a viscosity of 50mPa·s and a hydrogen mass fraction of 1.5wt%; the catalyst is a karstedt catalyst, and the platinum concentration contained in it is 3000ppm.

[0087] Comparative Example 1

[0088] S1 Add 500g of high hydroxyl MQ silicone resin (hydroxyl content 2.65wt%, weight average molecular weight 16000g / mol, molecular weight distribution coefficient 1.58) and 125g of xylene to a three-necked flask equipped with a stirrer, a thermometer and a condenser, and stir at room temperature until the high hydroxyl MQ silicone resin is completely dissolved. Add 100g of dimethylvinylethoxysilane and 3g of trifluoroacetic acid, heat to 60°C, stir and react for 5 hours, stop heating, add 10g of sodium carbonate, neutralize, stir for 0.5 hours, stop stirring, let stand, and filter with a positive pressure filter. Finally, transfer the filtrate to a flask, evaporate the low-boiling substances under reduced pressure, and obtain a white powdery solid, which is dissolved in deuterated chloroform, dimethyl terephthalate as the internal standard, and the vinyl content is 1.50wt% determined by 1H NMR; the weight average molecular weight is 16240g / mol and the molecular weight distribution coefficient is 1.55 determined by GPC.

[0089] S2: 70g of vinyl MQ resin, 10g of vinyl silicone oil and 20g of 1-decene are mixed and stirred to form a clear and transparent liquid, which is the peeling force control agent. The vinyl silicone oil has a viscosity of 60000mPa·s and a vinyl content of 0.10wt%. The vinyl content of the peeling force control agent is 3.78wt% and the viscosity is 493mPa·s.

[0090] S3: After 100g of vinyl silicone oil and 30g of peeling force control agent are evenly mixed, 5g of cross-linking agent and 5g of catalyst are added to prepare a release agent, wherein the vinyl silicone oil has a viscosity of 500mPa·s and a vinyl content of 1.2wt%; the cross-linking agent is a pendant hydrogen-containing silicone oil with a viscosity of 80mPa·s and a hydrogen mass fraction of 1.9wt%; the catalyst is a karstedt catalyst, and the platinum concentration contained in it is 5000ppm.

[0091] Comparative Example 2

[0092] S1: Add 500g of high-hydroxyl MQ silicone resin (hydroxyl content 2.98wt%, weight average molecular weight 19000g / mol, molecular weight distribution coefficient 1.66) and 214.29g of xylene to a three-necked flask equipped with a stirrer, a thermometer and a condenser, and stir at room temperature until the high-hydroxyl MQ silicone resin is completely dissolved. Add 71.12g of tetramethyl divinyl disiloxane and 2.5g of trifluoromethanesulfonic acid and 42.86g of cyclohexane (non-polar small molecule), heat to 80°C, stir and react for 3 hours, stop heating, add 7.85g of calcium carbonate, neutralize, stir for 1 hour, stop stirring, let stand, and filter with a positive pressure filter. Finally, the filtrate was transferred to a flask, and low-boiling products were evaporated under reduced pressure to obtain a white powdery solid, which was dissolved in deuterated chloroform with dimethyl terephthalate as the internal standard. The vinyl content was determined by 1H NMR to be 1.46 wt %; the weight average molecular weight was determined by GPC to be 19140 g / mol, and the molecular weight distribution coefficient was 1.68.

[0093] S2: 50g of vinyl MQ resin, 30g of vinyl silicone oil and 20g of 1-1-tridecene are mixed and stirred to form a clear and transparent liquid, which is the peeling force control agent. The viscosity of the vinyl silicone oil is 50000mPa·s and the vinyl content is 0.08wt%. The vinyl content of the peeling force control agent is 3.72wt% and the viscosity is 550mPa·s.

[0094] S3: After 100g of vinyl silicone oil and 20g of release force control agent are mixed evenly, 2g of cross-linking agent and 3g of catalyst are added to prepare a release agent, wherein the vinyl silicone oil has a viscosity of 300mPa·s and a vinyl content of 0.8wt%; the cross-linking agent is a pendant hydrogen-containing silicone oil with a viscosity of 50mPa·s and a hydrogen mass fraction of 1.5wt%; the catalyst is a karstedt catalyst, and the platinum concentration contained in it is 3000ppm.

[0095] Test Case

[0096] Use an applicator to coat the release agent evenly on the PET film, put it in an oven, and cure it at 120°C for 15 seconds to obtain a release film. Use a standard test tape to stick to the release film to measure the release force of the release agent. Release force test method: stick the standard test tape, Japanese 31B tape, with a width of 25mm, on the release film sample, roll it back and forth with a 2kg standard roller for 2 times, then place it at room temperature (23±2°C, relative humidity 50%) for 10 minutes, then use a computerized peel strength tester to peel it 180° at 300mm / min, test it 3 times, and take the average value. .

[0097] Table 1 Release force test results of release agents containing MQ resins with different vinyl contents

[0098]

[0099]

[0100] The present invention significantly improves the end-capping rate of high-hydroxyl MQ resin by introducing a five-membered ring or six-membered ring polar small molecule compound containing a single heteroatom as an auxiliary agent, and obtains an MQ resin with a high vinyl content. Compared with before the improvement, the vinyl content of the vinyl MQ resin prepared by the modification method of the present invention is 1.81% to 2.41wt%. The data of Example 5 and Comparative Example 2 further prove the positive effect of these polar small molecules on the end-capping reaction. The vinyl MQ resin prepared by the present invention is applied to the heavy peeling force control agent formulation of the release agent. As shown in the data of Table 1, the increase in the vinyl content of the MQ resin provides the release agent with a higher and more stable release force, and can be applied to systems requiring a higher release force.

[0101] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a vinyl MQ resin, the method comprising the following steps: 1) adding a solvent to the high hydroxyl MQ silicone resin and stirring thoroughly at room temperature until the silicone resin is dissolved; 2) adding a capping agent, a catalyst A, and a polar small molecule compound having a five-membered ring or a six-membered ring containing a single heteroatom as an auxiliary agent, and heating the reaction; 3) adding alkaline inorganic salt powder and stirring to carry out neutralization reaction; 4) After standing, filtering and evaporating, vinyl MQ resin is obtained.

2. The method according to claim 1, It is characterized in that In the step 1), the high hydroxyl MQ type silicone resin has the formula: (R 3 SiO 1 / 2 ) m (SiO 4 / 2 ) n , wherein R is hydrogen or methyl, the m / n molar ratio is 0.7 to 0.9, the OH group content is between 2.6 and 3.5 wt %, the weight average molecular weight is between 16,000 and 20,000 g / mol, and the molecular weight distribution coefficient is less than 2.0; preferably, the OH group content is between 2.65 and 2.98 wt %, the weight average molecular weight is between 16,000 and 19,000 g / mol, and the molecular weight distribution coefficient is between 1.58 and 1.

70.

3. The method according to claim 1 or 2, It is characterized in that In the step 1), the solvent is selected from one or more of naphtha, toluene and xylene, preferably xylene; and / or, in the step 1), the mass ratio of the high hydroxyl MQ silicone resin to the solvent is 7-5:4-1.

25.

4. The method according to any one of claims 1 to 3, It is characterized in that In the step 2), the polar small molecule compound containing a single heteroatom and a five-membered ring or a six-membered ring is selected from one or more of dihydrofuran, thiophene, tetrahydrothiophene, pyrrole, tetrahydropyrrole and pyridine.

5. The method according to any one of claims 1 to 4, It is characterized in that In the step 2), the end-capping agent is selected from one or more of tetramethyldivinyldisiloxane and dimethylvinylethoxysilane, preferably tetramethyldivinyldisiloxane; and / or, the catalyst A is selected from one or more of trifluoroacetic acid, trifluoromethanesulfonic acid, HCl, and HBr, preferably trifluoromethanesulfonic acid; and / or, in the step 2), the amount of the end-capping agent added is 10 to 20 parts, preferably 14 to 20 parts, relative to 100 parts of high hydroxyl MQ silicone resin; and / or, the amount of catalyst A added is 0.2 to 1 part, preferably 0.2 to 0.6 parts; and / or, the amount of the auxiliary agent added is 0.5 to 10% of the mass of the high hydroxyl silicone resin solution.

6. The method according to any one of claims 1 to 5, It is characterized in that The temperature of the temperature-raising reaction in step 2) is 50-100° C., and the reaction time is 2-8 hours; preferably, the reaction temperature is 60-90° C., and the reaction time is 3-5 hours; and / or, the alkaline inorganic salt in step 3) is selected from any one of calcium carbonate, sodium bicarbonate or sodium carbonate, preferably calcium carbonate; and / or, the added mass of the alkaline inorganic salt is 5-10 times, preferably 3-5 times, of the acid catalyst; and / or, the neutralization reaction time is 0.5-3 hours, preferably 0.5-1.5 hours.

7. Vinyl MQ resin prepared by the preparation method according to any one of claims 1 to 6.

8. A release agent, It is characterized in that The release agent comprises, in parts by mass: 100 parts of vinyl silicone oil A; 15 to 30 parts of a peel force control agent; 1 to 9 parts of a cross-linking agent; 1 to 9 parts of catalyst B; The release force control agent comprises, by weight: 50-70 parts of vinyl MQ resin; Vinyl silicone oil B 10-30 parts; 20-30 parts of hydrocarbon solvent; The vinyl MQ resin is selected from the vinyl MQ resin prepared by the preparation method according to any one of claims 1 to 6 or the vinyl MQ resin according to claim 7.

9. The release agent according to claim 8, It is characterized in that The viscosity of the vinyl silicone oil B is 30000-60000 mPa·s, preferably 50000-60000 mPa·s, and the vinyl content is 0.05-0.15 wt%, preferably 0.08-0.10 wt%; the hydrocarbon solvent is selected from long-chain olefins with 8-19 carbon atoms, preferably 10-15 carbon atoms; and / or, the viscosity of the vinyl silicone oil A is 200-800 mPa·s, and the vinyl content is 0.5-1.5 wt%; preferably, the viscosity of the vinyl silicone oil A is 300-500 mPa·s, and the vinyl content is 0.8-1.2 wt%.

10. The release agent according to claim 8 or 9, It is characterized in that The cross-linking agent is a pendant hydrogen-containing silicone oil with a viscosity of 10 to 100 mPa·s and a hydrogen-based mass fraction of 1.0 to 2.0 wt%; preferably, the viscosity is 50 to 80 mPa·s and the hydrogen-based mass fraction is 0.5 to 1.5 wt%; and / or, the catalyst B is a platinum catalyst containing a platinum concentration of 1000 to 5000 ppm; preferably, the catalyst B is a karstedt catalyst containing a platinum concentration of 3000 to 5000 ppm.

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