Shape memory gel composition, method of preparation and use thereof

Abstract

The application provides a shape memory gel composition, a preparation method and application thereof, and the shape memory gel composition comprises the following raw material components in mass fractions: modified rubber 30-45 parts; modified organic silicon 10-20 parts; tackifying resin 15-45 parts; aging agent 0.2 parts; catalyst 1 part; and filler 0.5-2 parts. The shape memory gel composition disclosed by the application has excellent bonding performance, tensile performance, impact resistance and heat resistance, and can meet the application requirements in the electronic field.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, and in particular to a shape memory gel composition, its preparation method, and its application. Background Technology

[0002] Shape memory polymers (SMPs) are a new type of functional polymer material that combines the properties of both plastics and rubber. They are produced by using modern polymer physics theories and polymer synthesis and modification techniques to molecularly combine and modify general-purpose polymer materials such as polyethylene, polyisoprene, polyester, copolyester, polyamide, copolyamide, and polyurethane. Through molecular design and structural adjustment, these materials are endowed with a specific shape (initial state) under certain conditions. When external conditions change, they can correspondingly change their shape and fix it (morphological transformation). If the external environment changes again in a specific way and according to a certain pattern, they can reversibly return to their initial state. This material possesses reversibility, repeatability, and programmability, and therefore is widely used in mechanical, medical, electronic, and environmental fields.

[0003] Shape memory polymers are composed of hard and soft segments as basic units. The hard segments determine the material's stiffness and strength, while the soft segments determine its deformation capacity. Hard and soft segments are usually arranged alternately or mixed together, forming an entangled network structure. The shape memory properties of the material can be controlled by adjusting the ratio of hard to soft segments. However, as a novel smart material, it suffers from drawbacks such as complex preparation processes, high process requirements, poor aging resistance, and stress relaxation after long-term use leading to a slower shape recovery rate.

[0004] In view of this, it is necessary to improve the existing shape memory polymers and their preparation methods to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to solve the problems of complex preparation process and high process requirements of shape memory polymers in the prior art, as well as poor aging resistance and stress relaxation caused by long-term use, which leads to a slowdown in shape recovery.

[0006] To achieve the above objectives, the present invention provides a shape memory gel composition comprising the following raw materials in parts by weight:

[0007] 30-45 parts of modified rubber;

[0008] 10-20 parts of modified organosilicon;

[0009] 15-45 parts of tackifying resin;

[0010] 0.2 parts of aging agent;

[0011] 1 part catalyst;

[0012] 0.5-2 parts of filler;

[0013] The shape memory gel composition is formed by swelling the modified rubber, the modified organosilicon, the tackifying resin, the aging agent, the catalyst, and the filler in a mixed solution of polyvinyl alcohol, water, and ethylene glycol, wherein the total mass parts of the modified rubber, the modified organosilicon, the tackifying resin, the aging agent, the catalyst, and the filler are 100 parts.

[0014] As a further improvement of the present invention, the mass ratio of the polyvinyl alcohol, the water and the ethylene glycol in the mixed solution is 1:3.7:4;

[0015] The modified rubber is selected from isobutylene-isoprene block copolymer (butyl rubber), butadiene-styrene block copolymer, natural rubber, and epoxides of cis-butadiene rubber.

[0016] As a further improvement of the present invention, the tackifying resin is selected from solid tackifying resins, or from a mixture of solid tackifying resins and liquid tackifying resins, and the softening temperature of the liquid tackifying resin is 0-35°C.

[0017] As a further improvement of the present invention, the catalyst is selected from one or any combination of potassium carbonate, sodium carbonate, tetrabutylammonium bromide, tetrabutylammonium fluoride, benzyltriethylammonium chloride, tetrabutylammonium hydrogen sulfate, triethylamine, 4-methylaminopyridine, 1,5,7-triazidobicyclo(4,4,0)dec-5-ene, and triphenylphosphine.

[0018] As a further improvement of the present invention, the filler is selected from one or any combination of several of the following: silver nanowires, silver powder, nickel powder, copper powder, silver-coated copper powder, carbon nanotubes, graphene, fumed silica, alumina, boron nitride, calcium carbonate, and titanium dioxide.

[0019] As a further improvement of the present invention, the aging agent is selected from one or any combination of several of the following: pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, butyl malonate mixtures, tris[2,4-di-tert-butylphenyl] phosphite, and 2,2-dimethylenebis-(4-methyl-6-tert-butylphenol).

[0020] Based on the same inventive concept, this invention also discloses a method for preparing a shape memory gel composition, comprising:

[0021] S1. Modified rubber, modified organosilicon, tackifying resin, catalyst, filler, aging agent and toluene are placed in a container, mixed evenly and allowed to stand to defoam, to obtain organosilicon-grafted rubber solution.

[0022] S2. The silicone-grafted rubber liquid is injected into a mold and baked in succession in temperature zones of 30-35℃, 40-45℃, 60-75℃, 90-100℃, and 110-120℃ to obtain a preliminary product with a fixed shape.

[0023] S3. Immerse the initial product in a mixed solution of polyvinyl alcohol, water and ethylene glycol, freeze it, and form a polyvinyl alcohol coating on the surface of the initial product to obtain the shape memory gel composition.

[0024] As a further improvement of the present invention, step S1 further includes: preparing the modified rubber, specifically as follows:

[0025] S11. Add n-hexane to a container to dissolve the rubber raw materials to prepare a primary rubber solution, and fully react the m-chloroperoxybenzoic acid added to the primary rubber solution to obtain a rubber solution.

[0026] S12. The rubber solution is washed sequentially with sodium hydroxide solution and deionized water until it is neutral. The neutral rubber solution is then precipitated in anhydrous ethanol, filtered, and dried to obtain the modified rubber.

[0027] As a further improvement of the present invention, in step S11, the mass concentration of the primary rubber solution is 5 wt%, the molar ratio of double bond to m-chloroperoxybenzoic acid is 1:1.1, and the reaction time is 30 minutes.

[0028] In step S12, the sodium hydroxide solution has a mass concentration of 4 wt%, and the modified rubber has an epoxy degree of 20-45%.

[0029] As a further improvement of the present invention, step S1 further includes: preparing the modified organosilicon, specifically as follows:

[0030] S13. Add hexamethyldisiloxane, mercaptopropylmethyldimethoxysilane, and dimethoxydisiloxane to excess toluene to obtain a mixture, wherein the molar ratio of hexamethyldisiloxane, mercaptopropylmethyldimethoxysilane, and dimethoxydisiloxane is 1:20:80.

[0031] S14. Slowly add concentrated hydrochloric acid to the mixture while keeping the temperature below 50°C. After uniform mixing, raise the temperature to 120°C and remove toluene by rotary evaporation to obtain the modified organosilicon.

[0032] Based on the same inventive concept, this invention also discloses an application of the shape memory gel composition according to any of the above inventions, wherein the shape memory gel composition is used as an adhesive.

[0033] Compared with the prior art, the beneficial effects of the present invention are:

[0034] The shape memory gel composition disclosed in this invention uses a graft copolymer of modified rubber and modified organosilicon as the main material. Polyvinyl alcohol and fillers are added, and the gel composition is formed through intermolecular interactions. Simultaneously, a mild curing and crosslinking technology enhances the gel's impact resistance and heat resistance. Under normal use conditions, it exhibits excellent adhesion strength to metal substrates, and after being subjected to tensile deformation, it can recover to its original state within a certain time. Attached Figure Description

[0035] Figure 1 This is a schematic diagram illustrating the steps of a method for preparing a shape memory gel composition disclosed in this invention;

[0036] Figure 2 This is a schematic diagram of the steps involved in preparing modified rubber.

[0037] Figure 3 This is a schematic diagram of the steps involved in preparing modified organosilicon. Detailed Implementation

[0038] The present invention will now be described in detail with reference to the embodiments shown in the accompanying drawings. However, it should be noted that these embodiments are not intended to limit the present invention. Equivalent changes or substitutions in function, method, or structure made by those skilled in the art based on these embodiments are all within the scope of protection of the present invention.

[0039] Please refer to Figures 1 to 3 As shown, this invention illustrates a specific embodiment of a method for preparing a shape memory gel composition. This preparation method includes at least the following steps S1 to S3.

[0040] Step S1: The modified rubber, modified organosilicon, tackifying resin, catalyst, filler, aging agent and toluene are placed in a container, mixed evenly and allowed to stand to defoam, to obtain organosilicon-grafted rubber solution.

[0041] Step S2: Inject the silicone-grafted rubber liquid into the mold and bake it in the temperature ranges of 30-35℃, 40-45℃, 60-75℃, 90-100℃, and 110-120℃ in sequence to obtain a preliminary product with a fixed shape.

[0042] Step S3: Immerse the initial product in a mixed solution of polyvinyl alcohol, water and ethylene glycol, and freeze it to form a polyvinyl alcohol coating on the surface of the initial product, thus obtaining a shape memory gel composition.

[0043] In one implementation, the reference Figure 2 As shown, step S1 further includes: preparing modified rubber, specifically including the following steps S11 to S12.

[0044] S11. Add n-hexane to a container to dissolve the rubber raw materials to prepare a primary rubber solution, and fully react the m-chloroperoxybenzoic acid added to the primary rubber solution to obtain the rubber solution.

[0045] S12. The rubber solution is washed sequentially with sodium hydroxide solution and deionized water until it is neutral. The neutral rubber solution is then precipitated in anhydrous ethanol, filtered, and dried to obtain modified rubber.

[0046] It should be noted that in step S11, the mass concentration of the primary rubber solution is 5 wt%, the molar ratio of double bond to m-chloroperoxybenzoic acid is 1:1.1, and the reaction time is 30 minutes; in step S12, the mass concentration of sodium hydroxide solution is 4 wt%, and the epoxy degree of the modified rubber is 20-45%.

[0047] In one implementation, the reference Figure 3 As shown, step S1 further includes: preparing modified organosilicon, specifically including the following steps S13 to S14.

[0048] S13. Add hexamethyldisiloxane, mercaptopropylmethyldimethoxysilane, and dimethoxydisiloxane to excess toluene to obtain a mixture with a molar ratio of hexamethyldisiloxane, mercaptopropylmethyldimethoxysilane, and dimethoxydisiloxane of 1:20:80.

[0049] S14. Slowly add concentrated hydrochloric acid to the mixture while keeping the temperature below 50°C. After uniform mixing, raise the temperature to 120°C. Use the azeotropic system of toluene and water to carry methanol and water out of the azeotropic system. After removing toluene by rotary evaporation, the modified organosilicon is obtained.

[0050] Meanwhile, this invention also discloses a shape memory gel composition, prepared based on the method for preparing the shape memory gel composition disclosed above, which comprises the following raw materials in parts by weight:

[0051] 30-45 parts of modified rubber;

[0052] 10-20 parts of modified organosilicon;

[0053] 15-45 parts of tackifying resin;

[0054] 0.2 parts of aging agent;

[0055] 1 part catalyst;

[0056] 0.5-2 parts of filler.

[0057] The shape memory gel composition is formed by swelling modified rubber, modified silicone, tackifying resin, aging agent, catalyst, and filler in a mixed solution of polyvinyl alcohol, water, and ethylene glycol, wherein the total mass parts of the modified rubber, modified silicone, tackifying resin, aging agent, catalyst, and filler are 100 parts. The mass ratio of polyvinyl alcohol, water, and ethylene glycol in the mixed solution is 1:3.7:4.

[0058] It should be noted that the modified rubber is selected from isobutylene-isoprene block copolymer (butyl rubber), butadiene-styrene block copolymer, natural rubber, and epoxides of cis-butadiene rubber. The tackifying resin is selected from solid tackifying resins, or a mixture of solid and liquid tackifying resins, wherein the softening temperature of the liquid tackifying resin is 0-35℃. The catalyst is selected from one or any combination of potassium carbonate, sodium carbonate, tetrabutylammonium bromide, tetrabutylammonium fluoride, benzyltriethylammonium chloride, tetrabutylammonium hydrogen sulfate, triethylamine, 4-methylaminopyridine, 1,5,7-triazidobicyclo(4,4,0)dec-5-ene, and triphenylphosphine. The filler is selected from one or any combination of silver nanowires, silver powder, nickel powder, copper powder, silver-coated copper powder, carbon nanotubes, graphene, fumed silica, alumina, boron nitride, calcium carbonate, and titanium dioxide. The aging agent is selected from one or any combination of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, a mixture of butyl malonate esters, tris[2,4-di-tert-butylphenyl] phosphite, and 2,2-dimethylenebis-(4-methyl-6-tert-butylphenol).

[0059] The shape memory gel composition disclosed in this invention uses butyl rubber (isobutylene-isoprene block copolymer) as the main material to achieve shape memory function. The dense arrangement of methyl groups on the side of the macromolecular chain of the isobutylene-isoprene block copolymer restricts the thermal motion of polymer molecules, and the high saturation gives the material good heat resistance and aging resistance. However, its slow vulcanization rate, poor mutual adhesion, and weak interaction with reinforcing agents limit its application range. This invention introduces polar epoxy groups into the macromolecular chain of the isobutylene-isoprene block copolymer through an oxidation reaction, and forms an effective organosilicon graft crosslinking structure through the mild click reaction of thiol-epoxy groups, increasing the molecular weight of the resin matrix and enhancing its impact resistance, heat resistance, adhesion, and compatibility with other polar polymer materials.

[0060] The shape memory gel composition disclosed in this invention uses a graft copolymer of modified rubber and modified organosilicon as the main material. Polyvinyl alcohol and fillers are added, and the gel composition is formed through intermolecular interactions. Simultaneously, a mild curing and crosslinking technology enhances the gel's impact resistance and heat resistance. Under normal use conditions, it exhibits excellent adhesion strength to metal substrates, and after being subjected to tensile deformation, it can recover to its original state within a certain time.

[0061] To better understand the preparation method of the shape memory gel composition provided in this application, specific examples are shown below to illustrate the preparation method.

[0062] Example 1:

[0063] 380 g of n-hexane and 20 g of isobutylene-isoprene block copolymer were added to a three-necked flask and mechanically stirred until completely dissolved. 0.1 mg of m-chloroperoxybenzoic acid was then added, and the mixture was reacted at 350 rpm and 40 °C for 30 minutes. The product was washed successively with 4 wt% sodium hydroxide solution and deionized water until neutral, then precipitated in anhydrous ethanol. The filtered product was dried in a vacuum oven at 45 °C to obtain epoxidized modified butyl rubber (i.e., the aforementioned modified rubber). The isobutylene-isoprene block copolymer was selected from butyl rubber, Yanshan Petrochemical IIR1751, with a viscosity-average relative molecular weight of 5.6 × 10⁻⁶. 5 g / mol, glass transition temperature -65℃, unsaturation 1.5%mol; chloroperoxybenzoic acid was selected from Aladdin, with a purity of 85%. The degree of epoxidation was determined by... 1 Characterized by ¹H NMR (Advance II 400M, Bruker, solvent d-CDCl₃, δ = 7.26), epoxy degree = A 2.73 / (A 2.73 +A' 5.07 )×100%, where A 2.73 A' represents the peak area of ​​the proton absorption peak on the epoxy group in the epoxidation product. 5.07 This represents the peak area of ​​the proton absorption peak on the double-bonded carbon at δ=5.07 in the epoxidized product. After testing, the epoxy degree of the epoxidized rubber product was calculated to be 30%.

[0064] A 1L three-necked flask was equipped with a mechanical stirrer, a thermometer, and a constant-pressure dropping funnel, and cooled using a water bath. 3.25g (0.02mol) of hexamethyldisiloxane, 72.1g (0.4mol) of mercaptopropylmethyldimethoxysilane, 192g (1.6mol) of dimethoxydisiloxane, and 260g of toluene were added sequentially to the flask. After thorough mixing with mechanical stirring, 344g (37wt%) of concentrated hydrochloric acid was added dropwise to the system from the constant-pressure dropping funnel, while maintaining the system temperature below 50°C. After the addition was complete, stirring continued for 48 hours to ensure complete hydrolysis of the raw materials. The system was then heated to 120°C in an oil bath. The methanol and water products were removed from the system through an azeotropic reaction of toluene and water. Trace amounts of toluene were removed by rotary evaporation, yielding the mercapto-modified organosilicon (i.e., the aforementioned modified organosilicon). After vacuum drying, the yield was calculated to be approximately 81%.

[0065] According to the mass fraction, add the ingredients in the following proportions:

[0066] 45 parts of modified rubber;

[0067] 15 parts of modified organosilicon;

[0068] 38 parts of tackifying resin;

[0069] 0.8 parts of fumed silica;

[0070] 0.2 parts of aging agent;

[0071] One part of tetrabutylammonium fluoride.

[0072] The above materials were dissolved / dispersed in toluene at a solid content of 50%, then thoroughly mixed using a three-roll mill. After standing to defoam, an organosilicon-grafted rubber solution was obtained. The rubber solution was injected into a mold and baked sequentially in ovens at 30℃, 40℃, 60℃, 90℃, and 110℃ for 10 minutes each to solidify and form samples. The samples were then immersed in a mixed solution of 15g of polyvinyl alcohol, 55mL of deionized water, and 55mL of ethylene glycol. After freezing, a uniform polyvinyl alcohol coating was applied to the surface to obtain a shape memory gel composition.

[0073] It should be noted that the modified rubber refers to epoxidized butyl rubber, selected from the epoxidized modified product of isobutylene-isoprene block copolymer, butyl rubber, Yanshan Petrochemical IIR1751. The modified organosilicon refers to mercapto-modified organosilicon. The tackifying resin includes 5 parts of CrayValley, Wingtack STS with a softening point of 94℃, 15 parts of Eastman PICCOLYTES135 terpene resin with a softening point of 135℃, 15 parts of Kraton, SylvarestrB115 terpene resin with a softening point of 115℃, and 3 parts of Kraton, Sylvatac RE10L liquid rosin ester. The fumed silica is selected from Wacker HDK H15. The aging agent is selected from Irganox 1076, BASF. Tetrabutylammonium fluoride is selected from Sigma-Aldrich.

[0074] Example 2:

[0075] The preparation methods of the modified rubber and modified organosilicon in Example 2 can be referred to in Example 1, and will not be repeated here.

[0076] By weight, add the following proportions:

[0077] 43 parts of modified rubber;

[0078] 16 parts of modified organosilicon;

[0079] 39 parts of tackifying resin;

[0080] 0.8 parts of fumed silica;

[0081] 0.2 parts of aging agent;

[0082] One part of tetrabutylammonium fluoride.

[0083] The above materials were dissolved / dispersed in toluene at a solid content of 50%, then thoroughly mixed using a three-roll mill. After standing to defoam, an organosilicon-grafted rubber solution was obtained. The rubber solution was injected into a mold and baked sequentially in ovens at 30℃, 40℃, 60℃, 90℃, and 110℃ for 10 minutes each to solidify and form samples. The samples were then immersed in a mixed solution of 15g of polyvinyl alcohol, 55mL of deionized water, and 55mL of ethylene glycol. After freezing, a uniform polyvinyl alcohol coating was applied to the surface to obtain a shape memory gel composition.

[0084] It should be noted that the modified rubber refers to epoxidized butyl rubber, which is selected from the epoxidized modified product of isobutylene-isoprene block copolymer, butyl rubber, and Yanshan Petrochemical IIR1751. The modified organosilicon refers to mercapto-modified organosilicon. The tackifying resin includes 5 parts of CrayValley, Wingtack STS with a softening point of 94℃, 14 parts of Eastman PICCOLYTE S135 terpene resin with a softening point of 135℃, 14 parts of Kraton, SylvarestrB115 terpene resin with a softening point of 115℃, and 6 parts of Kraton, Sylvatac RE10L liquid rosin ester. The fumed silica is selected from Wacker HDK H15. The aging agent is selected from Irganox 1076, BASF. Tetrabutylammonium fluoride is selected from Sigma-Aldrich.

[0085] Example 3:

[0086] The preparation methods of the modified rubber and modified organosilicon in Example 3 can be referred to in Example 1, and will not be repeated here.

[0087] By weight, add the following proportions:

[0088] 41 parts of modified rubber;

[0089] 18 parts of modified organosilicon;

[0090] 39 parts of tackifying resin;

[0091] 0.8 parts of fumed silica;

[0092] 0.2 parts of aging agent;

[0093] One part of tetrabutylammonium fluoride.

[0094] The above materials were dissolved / dispersed in toluene at a solid content of 50%, then thoroughly mixed using a three-roll mill. After standing to defoam, an organosilicon-grafted rubber solution was obtained. The rubber solution was injected into a mold and baked sequentially in ovens at 30℃, 40℃, 60℃, 90℃, and 110℃ for 10 minutes each to solidify and form samples. The samples were then immersed in a mixed solution of 15g of polyvinyl alcohol, 55mL of deionized water, and 55mL of ethylene glycol. After freezing, a uniform polyvinyl alcohol coating was applied to the surface to obtain a shape memory gel composition.

[0095] It should be noted that the modified rubber refers to epoxidized butyl rubber, which is selected from the epoxidized modified product of isobutylene-isoprene block copolymer, butyl rubber, and Yanshan Petrochemical IIR1751. The modified organosilicon refers to mercapto-modified organosilicon. The tackifying resin includes 6 parts of CrayValley, Wingtack STS with a softening point of 94℃, 14 parts of Eastman PICCOLYTE S135 terpene resin with a softening point of 135℃, 14 parts of Kraton, SylvarestrB115 terpene resin with a softening point of 115℃, and 5 parts of Kraton, Sylvatac RE10L liquid rosin ester. The fumed silica is selected from Wacker HDK H15. The aging agent is selected from Irganox 1076, BASF. Tetrabutylammonium fluoride is selected from Sigma-Aldrich.

[0096] Example 4:

[0097] The preparation methods of the modified rubber and modified organosilicon in Example 4 can be referred to in Example 1, and will not be repeated here.

[0098] By weight, add the following proportions:

[0099] 40 parts of modified rubber;

[0100] 19 parts of modified organosilicon;

[0101] 39 parts of tackifying resin;

[0102] 0.8 parts of fumed silica;

[0103] 0.2 parts of aging agent;

[0104] One part of tetrabutylammonium fluoride.

[0105] The above materials were dissolved / dispersed in toluene at a solid content of 50%, then thoroughly mixed using a three-roll mill. After standing to defoam, an organosilicon-grafted rubber solution was obtained. The rubber solution was injected into a mold and baked sequentially in ovens at 30℃, 40℃, 60℃, 90℃, and 110℃ for 10 minutes each to solidify and form samples. The samples were then immersed in a mixed solution of 15g of polyvinyl alcohol, 55mL of deionized water, and 55mL of ethylene glycol. After freezing, a uniform polyvinyl alcohol coating was applied to the surface to obtain a shape memory gel composition.

[0106] It should be noted that the modified rubber refers to epoxidized butyl rubber, which is selected from the epoxidized modified product of isobutylene-isoprene block copolymer, butyl rubber, and Yanshan Petrochemical IIR1751. The modified organosilicon refers to mercapto-modified organosilicon. The tackifying resin includes 5 parts of CrayValley, Wingtack STS with a softening point of 94℃, 14 parts of Eastman PICCOLYTE S135 terpene resin with a softening point of 135℃, 14 parts of Kraton, SylvarestrB115 terpene resin with a softening point of 115℃, and 6 parts of Kraton, Sylvatac RE10L liquid rosin ester. The fumed silica is selected from Wacker HDK H15. The aging agent is selected from Irganox 1076, BASF. Tetrabutylammonium fluoride is selected from Sigma-Aldrich.

[0107] Example 5

[0108] The preparation methods of the modified rubber and modified organosilicon in Example 5 can be referred to in Example 1, and will not be repeated here.

[0109] By weight, add the following proportions:

[0110] 30 parts of modified rubber;

[0111] 20 parts of modified organosilicon;

[0112] 48 parts of tackifying resin;

[0113] 0.8 parts of fumed silica;

[0114] 0.2 parts of aging agent;

[0115] One part of tetrabutylammonium fluoride.

[0116] The above materials were dissolved / dispersed in toluene at a solid content of 50%, then thoroughly mixed using a three-roll mill. After standing to defoam, an organosilicon-grafted rubber solution was obtained. The rubber solution was injected into a mold and baked sequentially in ovens at 30℃, 40℃, 60℃, 90℃, and 110℃ for 10 minutes each to solidify and form samples. The samples were then immersed in a mixed solution of 15g of polyvinyl alcohol, 55mL of deionized water, and 55mL of ethylene glycol. After freezing, a uniform polyvinyl alcohol coating was applied to the surface to obtain a shape memory gel composition.

[0117] It should be noted that the modified rubber refers to epoxidized butyl rubber, which is selected from the epoxidized modified product of isobutylene-isoprene block copolymer, butyl rubber, and Yanshan Petrochemical IIR1751. The modified organosilicon refers to mercapto-modified organosilicon. The tackifying resin includes 5 parts of CrayValley, Wingtack STS with a softening point of 94℃, 14 parts of Eastman PICCOLYTE S135 terpene resin with a softening point of 135℃, 14 parts of Kraton, SylvarestrB115 terpene resin with a softening point of 115℃, and 6 parts of Kraton, Sylvatac RE10L liquid rosin ester. The fumed silica is selected from Wacker HDK H15. The aging agent is selected from Irganox 1076, BASF. Tetrabutylammonium fluoride is selected from Sigma-Aldrich.

[0118] Example 6

[0119] The preparation methods of the modified rubber and modified organosilicon in Example 6 can be referred to in Example 1, and will not be repeated here.

[0120] By weight, add the following proportions:

[0121] 45 parts of modified rubber;

[0122] 10 parts of modified organosilicon;

[0123] 43 parts of tackifying resin;

[0124] 0.8 parts of fumed silica;

[0125] 0.2 parts of aging agent;

[0126] One part of tetrabutylammonium fluoride.

[0127] The above materials were dissolved / dispersed in toluene at a solid content of 50%, then thoroughly mixed using a three-roll mill. After standing to defoam, an organosilicon-grafted rubber solution was obtained. The rubber solution was injected into a mold and baked sequentially in ovens at 30℃, 40℃, 60℃, 90℃, and 110℃ for 10 minutes each to solidify and form samples. The samples were then immersed in a mixed solution of 15g of polyvinyl alcohol, 55mL of deionized water, and 55mL of ethylene glycol. After freezing, a uniform polyvinyl alcohol coating was applied to the surface to obtain a shape memory gel composition.

[0128] It should be noted that the modified rubber refers to epoxidized butyl rubber, which is selected from the epoxidized modified product of isobutylene-isoprene block copolymer, butyl rubber, and Yanshan Petrochemical IIR1751. The modified organosilicon refers to mercapto-modified organosilicon. The tackifying resin includes 5 parts of CrayValley, Wingtack STS with a softening point of 94℃, 14 parts of Eastman PICCOLYTE S135 terpene resin with a softening point of 135℃, 14 parts of Kraton, SylvarestrB115 terpene resin with a softening point of 115℃, and 6 parts of Kraton, Sylvatac RE10L liquid rosin ester. The fumed silica is selected from Wacker HDK H15. The aging agent is selected from Irganox 1076, BASF. Tetrabutylammonium fluoride is selected from Sigma-Aldrich.

[0129] Example 7

[0130] The preparation methods of the modified rubber and modified organosilicon in Example 7 can be referred to in Example 1, and will not be repeated here.

[0131] By weight, add the following proportions:

[0132] 45 parts of modified rubber;

[0133] 38 parts of modified organosilicon;

[0134] 15 parts of tackifying resin;

[0135] 0.8 parts of fumed silica;

[0136] 0.2 parts of aging agent;

[0137] One part of tetrabutylammonium fluoride.

[0138] The above materials were dissolved / dispersed in toluene at a solid content of 50%, then thoroughly mixed using a three-roll mill. After standing to defoam, an organosilicon-grafted rubber solution was obtained. The rubber solution was injected into a mold and baked sequentially in ovens at 30℃, 40℃, 60℃, 90℃, and 110℃ for 10 minutes each to solidify and form samples. The samples were then immersed in a mixed solution of 15g of polyvinyl alcohol, 55mL of deionized water, and 55mL of ethylene glycol. After freezing, a uniform polyvinyl alcohol coating was applied to the surface to obtain a shape memory gel composition.

[0139] It should be noted that the modified rubber refers to epoxidized butyl rubber, which is selected from the epoxidized modified product of isobutylene-isoprene block copolymer, butyl rubber, and Yanshan Petrochemical IIR1751. The modified organosilicon refers to mercapto-modified organosilicon. The tackifying resin includes 5 parts of CrayValley, Wingtack STS with a softening point of 94℃, 14 parts of Eastman PICCOLYTE S135 terpene resin with a softening point of 135℃, 14 parts of Kraton, SylvarestrB115 terpene resin with a softening point of 115℃, and 6 parts of Kraton, Sylvatac RE10L liquid rosin ester. The fumed silica is selected from Wacker HDK H15. The aging agent is selected from Irganox 1076, BASF. Tetrabutylammonium fluoride is selected from Sigma-Aldrich.

[0140] Comparative Example 1:

[0141] By weight, add the following proportions:

[0142] 45 parts of butyl rubber;

[0143] 40 parts of tackifying resin;

[0144] 0.8 parts of fumed silica;

[0145] 14 parts naphthenic oil;

[0146] 0.2 parts of aging agent.

[0147] The above materials were dissolved / dispersed in toluene at a solid content of 50%, then thoroughly mixed using a three-roll mill. After standing to defoam, a rubber adhesive was obtained. The rubber adhesive was injected into a mold and baked sequentially in ovens at 30℃, 40℃, 60℃, 90℃, and 110℃ for 10 minutes each to solidify and form samples. The samples were then immersed in a mixed solution of 15g of polyvinyl alcohol, 55mL of deionized water, and 55mL of ethylene glycol. After freezing, a uniform polyvinyl alcohol coating was applied to the surface to obtain a shape memory gel composition.

[0148] It should be noted that the butyl rubber is selected from Yanshan Petrochemical IIR1751. The tackifying resins include 5 parts of Cray Valley, Wingtack STS (softening point 94℃), 15 parts of Eastman PICCOLYTE S135 terpene resin (softening point 135℃), 15 parts of Kraton, Sylvarestr B115 terpene resin (softening point 115℃), and 5 parts of Kraton, Sylvatac RE10L liquid rosin ester. Fumed silica is selected from Wacker HDK H15. Naphthenic oil is selected from KN4010 (Karamay). The aging agent is selected from Irganox 1076 (BASF).

[0149] Comparative Example 2:

[0150] By weight, add the following proportions:

[0151] 45 parts of styrene-isoprene-styrene block copolymer;

[0152] 40 parts of tackifying resin;

[0153] 0.8 parts of fumed silica;

[0154] 14 parts naphthenic oil;

[0155] 0.2 parts of aging agent.

[0156] The above materials were dissolved / dispersed in toluene at a solid content of 50%, then thoroughly mixed using a three-roll mill. After standing to defoam, a rubber adhesive was obtained. The rubber adhesive was injected into a mold and baked sequentially in ovens at 30℃, 40℃, 60℃, 90℃, and 110℃ for 10 minutes each to solidify and form samples. The samples were then immersed in a mixed solution of 15g of polyvinyl alcohol, 55mL of deionized water, and 55mL of ethylene glycol. After freezing, a uniform polyvinyl alcohol coating was applied to the surface to obtain a shape memory gel composition.

[0157] It should be noted that the styrene-isoprene-styrene block copolymer is selected from SIS, Kraton, D1163 P. The tackifying resin includes 5 parts of Cray Valley, Wingtack STS with a softening point of 94℃, 15 parts of Eastman PICCOLYTE S135 terpene resin with a softening point of 135℃, 15 parts of Kraton, Sylvarestr B115 terpene resin with a softening point of 115℃, and 5 parts of Kraton, Sylvatac RE10L liquid rosin ester. The fumed silica is selected from Wacker HDK H15. The naphthenic oil is selected from KN4010, Karamay. The aging agent is selected from Irganox 1076, BASF.

[0158] Tensile properties were tested on the shape memory gel compositions prepared in the seven examples (i.e., examples 1 to 7) and the two comparative examples (i.e., comparative example 1 and comparative example 2). The samples were prepared in accordance with the standard DIN-53504S3 and tensile tests were performed using an electronic universal tensile testing machine at a speed of 100 mm / min. Each sample was tested in parallel three times.

[0159] The shape memory gel compositions prepared in the seven examples (i.e., examples 1 to 7) and the two comparative examples (i.e., comparative example 1 and comparative example 2) were subjected to deformation recovery performance tests. During the test, an electronic universal tensile testing machine was used, and the program was set to cyclic stretching mode. The samples were stretched to different deformations (50%, 100%, 200%, 400%, 800%, and 1200%) at a rate of 400% / min. Then, the load was unloaded and the samples were returned to their original positions at the original rate. The load-unloading curves were obtained and the rebound rate was calculated.

[0160] Following the method defined in ASTM D 3330, the prepared hydrogel sample was cut into 25mm*25mm pieces and adhered to two metal substrates. The adhesion strength was then tested using a tensile testing machine. The test data are shown in Table 1 below.

[0161]

[0162]

[0163] Table 1

[0164] Comparative Example 1 and Comparative Example 2 used butyl rubber and SIS, two unmodified rubbers, as the main materials of the rubber strips, respectively. Without the addition of modified organosilicon, there is no cross-linking reaction process. Although the adhesive force, tensile strength and elongation at break are relatively good, the deformation recovery performance after stretching is poor. It is easy to break after stretching and cannot achieve rebound.

[0165] Examples 1 to 7 are 150μm shape memory gel strips prepared according to the present invention. Examples 1 to 7 all use the modified rubber, modified silicone, and tackifying resin mentioned in the present invention as the main materials for the strip structure. Examples 1 to 7 illustrate the median, lower limit, and upper limit of the above three main materials. As can be seen from the table above, examples 1 to 7 all achieved crosslinking of the modified rubber and modified silicone. Under different test conditions, the adhesive force, tensile strength, elongation at break, and deformation resilience of the strips remained at a high level. Therefore, the shape memory gel composition disclosed in this application has good impact resistance and heat resistance, excellent bonding strength to metal substrates under normal use conditions, and can recover to its original state within a certain period of time after being subjected to tensile deformation by external force.

[0166] Based on the same inventive concept, this invention also discloses the application of shape memory gel composition as an adhesive, which can be used as an adhesive in fields such as machinery, medicine, electronics, and environment.

[0167] The detailed descriptions listed above are merely specific descriptions of feasible embodiments of the present invention, and are not intended to limit the scope of protection of the present invention. All equivalent embodiments or modifications made without departing from the spirit of the present invention should be included within the scope of protection of the present invention.

[0168] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims. Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity, and those skilled in the art should consider the specification as a whole. The technical solutions in each embodiment can also be...

[0169] With appropriate combinations, other implementation methods can be formed that can be understood by those skilled in the art.

Claims

1. A shape memory gel composition, characterized in that, The raw materials include the following parts by weight: Epoxidized modified butyl rubber, 30-45 parts; 10-20 parts of mercapto-modified organosilicon; 15-45 parts of tackifying resin; 0.2 parts of aging agent; 1 part catalyst; 0.5-2 parts of filler; The shape memory gel composition is formed by swelling the epoxidized butyl rubber, the mercapto-modified organosilicon, the tackifying resin, the aging agent, the catalyst, and the filler in a mixed solution of polyvinyl alcohol, water, and ethylene glycol, wherein the sum of the mass parts of the epoxidized butyl rubber, the mercapto-modified organosilicon, the tackifying resin, the aging agent, the catalyst, and the filler is 100 parts. The epoxidized butyl rubber is prepared by dissolving isobutylene-isoprene block copolymer in hexane in a container to prepare a primary rubber solution, and then adding m-chloroperoxybenzoic acid to the primary rubber solution for a complete reaction to obtain a rubber solution. The rubber solution is washed sequentially with sodium hydroxide solution and deionized water until neutral. The neutral rubber solution is then precipitated in anhydrous ethanol, filtered, and dried to obtain the final product. The mercapto-modified organosilicon is prepared by adding hexamethyldisiloxane, mercaptopropylmethyldimethoxysilane, and dimethoxydisiloxane to an excess of toluene to obtain a mixture. Concentrated hydrochloric acid is slowly added dropwise to the mixture while maintaining the temperature below 50°C. After uniform mixing, the temperature is raised to 120°C, and toluene is removed by rotary evaporation.

2. The shape memory gel composition according to claim 1, characterized in that, The mass ratio of the polyvinyl alcohol, the water, and the ethylene glycol in the mixed solution is 1:3.7:

4.

3. The shape memory gel composition according to claim 1, characterized in that, The tackifying resin is selected from solid tackifying resins, or from a mixture of solid tackifying resins and liquid tackifying resins, and the softening temperature of the liquid tackifying resin is 0-35°C.

4. The shape memory gel composition according to claim 1, characterized in that, The catalyst is selected from one or any combination of potassium carbonate, sodium carbonate, tetrabutylammonium bromide, tetrabutylammonium fluoride, benzyltriethylammonium chloride, tetrabutylammonium hydrogen sulfate, triethylamine, 4-methylaminopyridine, and 1,5,7-triazidobicyclo(4,4,0)dec-5-ene.

5. The shape memory gel composition according to claim 1, characterized in that, The filler is selected from one or any combination of fumed silica, alumina, boron nitride, calcium carbonate, and titanium dioxide.

6. The shape memory gel composition according to claim 1, characterized in that, The aging agent is selected from one or any combination of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, tris[2,4-di-tert-butylphenyl]phosphite, and 2,2-dimethylenebis-(4-methyl-6-tert-butylphenol).

7. A method for preparing a shape memory gel composition according to any one of claims 1-6, characterized in that, include: S1. Epoxidized modified butyl rubber, mercapto modified organosilicon, tackifying resin, catalyst, filler, aging agent and toluene are placed in a container, mixed evenly and allowed to stand to defoam, to obtain organosilicon-grafted rubber solution. S2. The silicone-grafted rubber liquid is injected into a mold and baked in succession in temperature zones of 30-35℃, 40-45℃, 60-75℃, 90-100℃, and 110-120℃ to obtain a preliminary product with a fixed shape. S3. Immerse the initial product in a mixed solution of polyvinyl alcohol, water and ethylene glycol, freeze it, and form a polyvinyl alcohol coating on the surface of the initial product to obtain the shape memory gel composition. Step S1 further includes: preparing the epoxidized modified butyl rubber, specifically as follows: S11. Add n-hexane to a container to dissolve the isobutylene-isoprene block copolymer to prepare a primary rubber solution, and add m-chloroperoxybenzoic acid to the primary rubber solution to react fully to obtain a rubber solution. S12. The rubber solution is washed sequentially with sodium hydroxide solution and deionized water until it is neutral. The neutral rubber solution is precipitated in anhydrous ethanol, filtered, and dried to obtain the epoxidized modified butyl rubber. Step S1 further includes: preparing the thiol-modified organosilicon, specifically as follows: S13. Add hexamethyldisiloxane, mercaptopropylmethyldimethoxysilane, and dimethoxydisiloxane to excess toluene to obtain a mixture; S14. Slowly add concentrated hydrochloric acid to the mixture while keeping the temperature below 50°C. After uniform mixing, raise the temperature to 120°C and remove toluene by rotary evaporation to obtain the mercapto-modified organosilicon.

8. The method for preparing the shape memory gel composition according to claim 7, characterized in that, In step S11, the mass concentration of the primary rubber solution is 5 wt%, the molar ratio of double bond to m-chloroperoxybenzoic acid is 1:1.1, and the reaction time is 30 minutes. In step S12, the sodium hydroxide solution has a mass concentration of 4 wt%, and the epoxy degree of the epoxidized butyl rubber is 20-45%.

9. The method for preparing the shape memory gel composition according to claim 7, characterized in that, The molar ratio of hexamethyldisiloxane, mercaptopropylmethyldimethoxysilane, and dimethoxydisiloxane is 1:20:

80.

10. The application of a shape memory gel composition according to any one of claims 1-6, characterized in that, The shape memory gel composition serves as an adhesive.

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