Coupling rubber pad and preparation method thereof

Abstract

The invention relates to the technical field of rubber pads, in particular to a coupling rubber pad and a preparation method thereof.Copolymerized epichlorohydrin rubber and homopolymerized epichlorohydrin rubber are compounded to serve as a rubber pad base material, compound rosin is introduced to serve as a tackifier, an acrylate group is introduced into rosin, hydrogenated rosin-based acrylate is obtained, copolymerization is initiated through light, and the coupling rubber pad is prepared. Grafting double-bond terminated poly (carbamate-urea) and 3-acrylamido phenylboronic acid to obtain composite rosin; due to the introduction of double-bond terminated poly (carbamate-urea), the rubber pad has certain self-repairability, and the durability and fatigue resistance of the rubber pad are improved; 3-acrylamido phenylboronic acid is introduced, so that the biocompatibility of the rubber pad is improved; carbon black is subjected to modification treatment, the carbon black is subjected to double bond treatment through vinyl trimethylsilane, then a salicylaldehyde derivative containing double bonds and ammonium is grafted through light click, modified carbon black is obtained, and therefore the service life of the coupling rubber pad is prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of rubber pads, in particular to a coupling rubber pad and a preparation method thereof. BACKGROUND

[0002] As a key component of acoustic transmission medium, the coupling pad is widely used in medical ultrasonic diagnosis and industrial nondestructive testing fields. At present, the coupling pad is mostly based on hydrogel as the base material. Although the hydrogel has good biocompatibility and initial acoustic performance, its inherent defects, such as harsh storage environment, usually as a one-time consumable, high single detection cost, poor strength and the like also limit its application place.

[0003] At present, the reusable solid coupling pad on the market is mostly based on rubber as the base material. However, the interface between the rubber matrix and the reinforcing filler is weak, which can easily lead to interface debonding under long-term dynamic stress or in a humid heat environment, resulting in micro defects, thereby increasing the scattering loss of acoustic waves and reducing the effect. In addition, in order to improve the self-adhesion and processability of the rubber, the conventional tackifying resin is added, and the chemical stability of the tackifying resin is often insufficient, which can migrate in long-term use, thereby affecting the uniformity and durability of the product. At the same time, the poor antibacterial property of the tackifying resin can easily breed bacteria in a humid heat environment, thereby bringing health and safety hazards. SUMMARY

[0004] The present application aims to provide a coupling rubber pad and a preparation method thereof to solve the problems in the prior art.

[0005] In order to solve the above technical problems, the present application provides the following technical scheme:

[0006] A preparation method of a coupling rubber pad, comprising the following steps:

[0007] The chloroether rubber is put into a banbury mixer, then the tackifier, the scorch retarder, the plasticizer, the antioxidant, the lubricant, the acid absorber and the carbon black are sequentially added, mixed, sheeted, cooled and placed, then the vulcanizing agent and the accelerator are added, filtered, sheeted, placed and vulcanized to obtain a coupling rubber pad.

[0008] Further, the raw material components of the coupling rubber pad are chloroether rubber 60-65 parts, tackifier 1-3 parts, vulcanizing agent 0.5-1.5 parts, accelerator 2.1-3.2 parts, scorch retarder 0.4-0.5 parts, plasticizer 6.5-9 parts, antioxidant 0.3-0.5 parts, lubricant 1.5-2.8 parts, acid absorber 0.3-0.5 parts and carbon black 18-21 parts by weight.

[0009] Further, the raw material components for coupling the rubber pad are, by weight parts: chloro ether rubber 62-63 parts, tackifier 1-2 parts, vulcanizing agent 0.5-1.5 parts, accelerator 2.1-3.2 parts, anti-scorching agent 0.4-0.5 parts, plasticizer 6.5-9 parts, antioxidant 0.3-0.5 parts, lubricant 1.5-2.8 parts, acid absorber 0.3-0.5 parts, and carbon black 20-21 parts.

[0010] Further, the chloro ether rubber is a copolymer chloro ether rubber and a homopolymer chloro ether rubber compounded at a mass ratio of 2:1.

[0011] Further, the tackifier is rosin, the vulcanizing agent is trithiocyanuric acid, the anti-scorching agent is N-cyclohexyl thio phthalimide, the antioxidant is nickel dibutyl dithiocarbamate, and the acid absorber is zeolite.

[0012] Further, the accelerator is one or a compound of magnesium oxide and triallyl isocyanurate.

[0013] Further, the accelerator is a compound of magnesium oxide and triallyl isocyanurate at a mass ratio of (2-3):(0.1-0.2).

[0014] Further, the plasticizer is one or a compound of di[2-(2-butoxyethoxy)ethyl] adipate, paraffin oil, and dioctyl sebacate.

[0015] Further, the plasticizer is a compound of di[2-(2-butoxyethoxy)ethyl] adipate, paraffin oil, and dioctyl sebacate at a mass ratio of (5-6):(1-2):(0.5-1).

[0016] Further, the lubricant is one or a compound of glyceryl stearate, stearic amide, stearic acid, dioctyl phthalate, and triethyl citrate.

[0017] Further, the lubricant is a compound of glyceryl stearate, stearic amide, stearic acid, dioctyl phthalate, and triethyl citrate at a mass ratio of (0.1-0.2):(0.3-0.4):(1-2):(0.05-0.1):(0.05-0.1).

[0018] Further, the tackifier is a compound of rosin and complex rosin at a mass ratio of 1:1, and the preparation of the complex rosin comprises the following steps:

[0019] 1) mixing hydrogenated rosin, glycidyl methacrylate, p-hydroxyanisole, and triethylamine under a nitrogen atmosphere, heating to 85-88°C for 2-3h, and then heating to 115-120°C for 3-4h to obtain a hydrogenated rosin-based acrylate resin;

[0020] 2) mixing polytetrahydrofuran, isophorone diisocyanate, toluene-2, 4-diisocyanate, N, N-dimethylacetamide, dibutyl tin dilaurate under nitrogen atmosphere, stirring at 55-60℃ for 50-70min, adding the mixed solution of adipic dihydrazide, N, N-dimethylacetamide, warming to 115-120℃, keeping for 5-6h, adding 2- (tert-butylamino) ethyl methacrylate, keeping for 20-30min, to obtain double bond capped poly (urethane-urea) ;

[0021] 3) mixing hydrogenated rosin-based acrylate resin, double bond capped poly (urethane-urea), 3-acrylamidophenylboronic acid, N, N-dimethylformamide, adding photoinitiator, warming to 50-60℃, irradiating under 365nm light for 5-6h, centrifuging, washing, drying, to obtain composite rosin.

[0022] Further, the carbon black is modified by the following preparation steps:

[0023] (1) mixing vinyltrimethylsilane, anhydrous ethanol, acetic acid, stirring for 30-40min, adding the mixed solution of anhydrous ethanol, carbon black, ultrasonic treatment for 30-40min, warming to 75-80℃, keeping for 4-5h under stirring, centrifuging, washing, drying, to obtain double bond modified carbon black;

[0024] (2) mixing double bond modified carbon black, double bond and ammonium containing salicylaldehyde derivative, N, N-dimethylformamide, adding photoinitiator, warming to 40-50℃, irradiating under 365nm light for 5-6h, centrifuging, washing, drying, to obtain modified carbon black.

[0025] Further, the preparation of double bond and ammonium containing salicylaldehyde derivative includes the following steps:

[0026] A. mixing 2- (dimethylamino) ethyl methacrylate, acetone under nitrogen atmosphere, stirring at 0℃ for 8-12min, adding the mixed solution of 5- (chloromethyl) -2-hydroxybenzaldehyde, acetone, keeping for 4-5h, filtering, recrystallizing, drying, to obtain N- (3-aldehyde-4-hydroxybenzyl) -2- (methacryloyloxy) -N, N-dimethyl ethyl-1-ammonium chloride;

[0027] B. mixing N- (3-aldehyde-4-hydroxybenzyl) -2- (methacryloyloxy) -N, N-dimethyl ethyl-1-ammonium chloride, methanol under nitrogen atmosphere, adding the mixed solution of methanol, 3, 4-dihydroxybenzhydrazide, stirring at 18-25℃ for 11-12h, vacuum rotary evaporation, recrystallizing, drying, to obtain double bond and ammonium containing salicylaldehyde derivative.

[0028] Compared with the prior art, the present application has the following advantages:

[0029] The application provides a coupling rubber pad and a preparation method thereof.

[0030] In the application, copolymerization type and homopolymerization type chloro-ether rubber are used as rubber pad base materials, and rosin is used as tackifier, in order to improve the chemical stability and durability of the tackifier, composite rosin is introduced as the tackifier, hydrogenated rosin-based acrylate is obtained by introducing acrylate groups into rosin, and a multifunctional composite rosin is obtained by using light-induced copolymerization to graft double bond end-capped poly (urethane-urea) and 3-acrylamide benzene boronic acid, wherein the double bond end-capped poly (urethane-urea) is prepared by using polytetrahydrofuran as a soft segment, isophorone diisocyanate and toluene-2,4-diisocyanate as hard segments, adipic acid dihydrazide as a chain extender, introducing dynamic reversible crosslinking points and multiple hydrogen bonds, and reacting 2- (tert-butylamino) ethyl methacrylate with isocyanate groups to further enhance the dynamic crosslinking points; the introduction of the double bond end-capped poly (urethane-urea) endows the rubber pad with certain self-repairing property, improves the durability and fatigue resistance of the rubber pad; and the introduction of 3-acrylamide benzene boronic acid improves the biocompatibility of the rubber pad.

[0031] In the application, carbon black is used as a reinforcing filler, in order to improve the bonding strength of carbon black and rubber pad base material, the carbon black is modified, first, the carbon black is double-bonded by using vinyl trimethylsilane, and then the salicylaldehyde derivative containing double bonds and ammonium is grafted by light; wherein the salicylaldehyde derivative containing double bonds and ammonium is prepared by reacting 5- (chloromethyl) -2-hydroxybenzaldehyde with 2- (dimethylamino) ethyl methacrylate to obtain N- (3-aldehyde-4-hydroxybenzyl) -2- (methacryloyloxy) -N, N-dimethyl ethyl-1-ammonium chloride, and then Schiff base reaction with 3, 4-dihydroxybenzoyl hydrazine; the introduction of the quaternary ammonium salt cation of the salicylaldehyde derivative containing double bonds and ammonium endows the rubber pad with antibacterial property and improves the use safety of the rubber pad, the o-diphenol structure can reversibly react with the benzene boronic acid group in the composite rosin to form a dynamic borate ester bond; through the modification of carbon black and the cooperation of composite rosin, a multiple crosslinking network integrating covalent bond, dynamic borate ester bond, urethane-urea dynamic bond and hydrogen bond is constructed in the rubber matrix, which greatly improves the internal defects, enables the sound wave energy to pass more efficiently, significantly reduces the scattering loss, improves the stability of the acoustic performance, and the dense crosslinking network and self-repairing mechanism enable the rubber pad to have excellent mechanical properties and effectively restore the micro-damage generated during use, thereby prolonging the service life of the coupling rubber pad. DETAILED DESCRIPTION

[0032] The technical solutions in the present application will be described clearly and completely below in combination with the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0033] In addition, the technical solutions among various embodiments can be combined with each other, but it must be based on the premise that a person of ordinary skill in the art can realize it. When the combination of technical solutions appears to be contradictory or unachievable, it should be considered that the combination of technical solutions does not exist and is not within the protection scope required by the present application.

[0034] The technical solutions of the present application will be described in further detail below in combination with specific embodiments. It should be understood that the following embodiments are only used to explain the present application, and are not used to limit the present application.

[0035] Embodiment 1: A preparation method of a coupling rubber pad, comprising the following steps:

[0036] The chloro ether rubber is put into a mixer, then the tackifier, scorch retarder, plasticizer, antioxidant, lubricant, acid absorber, and carbon black are sequentially added, mixed, sheeted, cooled and placed, then the vulcanizing agent and accelerator are added, filtered, sheeted, placed, and vulcanized to obtain a coupling rubber pad;

[0037] The raw material components of the coupling rubber pad are chloro ether rubber 60 parts, tackifier 1 part, vulcanizing agent 0.5 part, accelerator 2.1 parts, scorch retarder 0.4 part, plasticizer 6.5 parts, antioxidant 0.3 part, lubricant 1.5 parts, acid absorber 0.3 part, and carbon black 18 parts, by weight;

[0038] The vulcanizing agent is trithiocyanuric acid, the scorch retarder is N-cyclohexylthiophthalimide, the antioxidant is nickel dibutyldithiocarbamate, and the acid absorber is zeolite;

[0039] The accelerator is magnesium oxide and triallyl isocyanurate, which are compounded in a mass ratio of 2:0.1;

[0040] The plasticizer is di[2-(2-butoxyethoxy)ethyl] adipate, paraffin oil, and dioctyl sebacate, which are compounded in a mass ratio of 5:1:0.5;

[0041] The lubricant is glyceryl stearate, stearic amide, stearic acid, dioctyl phthalate, and triethyl citrate, which are compounded in a mass ratio of 0.1:0.3:1:0.05:0.05;

[0042] The tackifier is rosin and compound rosin, which are compounded in a mass ratio of 1:1. The preparation of the compound rosin comprises the following steps:

[0043] 1) 3.34 g of hydrogenated rosin, 1.4 g of glycidyl methacrylate, 3 mg of p-hydroxyanisole, 6 mg of triethylamine were mixed under a nitrogen atmosphere, warmed to 85°C for 3 h, and then warmed to 115°C for 4 h to obtain a hydrogenated rosin-based methacrylate resin;

[0044] 2) 2 g of polytetrahydrofuran, 0.71 g of isophorone diisocyanate, 0.14 g of toluene-2,4-diisocyanate, 5 mL of N,N-dimethylacetamide, 5.7 mg of dibutyltin dilaurate were mixed under a nitrogen atmosphere, stirred at 55°C for 70 min, and then a mixture of 0.17 g of adipic acid dihydrazide and 5 mL of N,N-dimethylacetamide was added, warmed to 115°C, and held for 6 h. Then, 0.37 g of 2-(tert-butylamino)ethyl methacrylate was added, and held for 20 min to obtain a double bond-terminated poly(urethane-urea);

[0045] 3) 4.2 g of the hydrogenated rosin-based methacrylate resin, 1.8 g of the double bond-terminated poly(urethane-urea), 1.2 g of 3-acrylamidophenylboronic acid, and 30 mL of N,N-dimethylformamide were mixed, 0.08 g of a photoinitiator was added, warmed to 50°C, and irradiated under 365 nm light for 6 h. Then, the mixture was centrifuged, washed, and dried to obtain a composite rosin;

[0046] The carbon black was modified by the following preparation steps:

[0047] (1) 134 mg of vinyltrimethylsilane, 20 mL of anhydrous ethanol, and 2 mL of acetic acid were mixed and stirred for 30 min. Then, a mixture of 60 mL of anhydrous ethanol and 2 g of carbon black was added, ultrasonically treated for 30 min, warmed to 75°C, and stirred for 4 h. Then, the mixture was centrifuged, washed, and dried to obtain double bond-modified carbon black;

[0048] (2) 1.5 g of the double bond-modified carbon black, 0.3 g of a salicylaldehyde derivative containing a double bond and an ammonium group, and 20 mL of N,N-dimethylformamide were mixed, 0.02 g of a photoinitiator was added, warmed to 40°C, and irradiated under 365 nm light for 5 h. Then, the mixture was centrifuged, washed, and dried to obtain modified carbon black;

[0049] The salicylaldehyde derivative containing a double bond and an ammonium group was prepared by the following steps:

[0050] A. 5.2 mL of 2-(dimethylamino)ethyl methacrylate and 16 mL of acetone were mixed under a nitrogen atmosphere, stirred at 0°C for 8 min, and then a mixture of 5.4 g of 5-(chloromethyl)-2-hydroxybenzaldehyde and 4 mL of acetone was added. The mixture was held for 4 h, filtered, recrystallized, and dried to obtain N-(3-formyl-4-hydroxybenzyl)-2-(methacryloyloxy)-N,N-dimethylethyl-1- ammonium chloride;

[0051] B. Under a nitrogen atmosphere, 1 mmol of N-(3-formyl-4-hydroxybenzyl)-2- (methacryloyloxy)-N,N-dimethylethyl-1-aminium chloride, 4 mL of methanol, 1 mmol of 3,4-dihydroxybenzhydrazide were mixed, and the mixture was stirred at 18°C for 12 h, vacuum rotary evaporation, recrystallization, and drying to obtain a salicylaldehyde derivative containing a double bond and an ammonium group.

[0052] Example 2: A preparation method of a coupling rubber pad, comprising the following steps:

[0053] The chloro ether rubber was put into a mixer, then tackifier, scorch retarder, plasticizer, antioxidant, lubricant, acid absorbent, and carbon black were sequentially added, mixed, sheeted, cooled and placed, then vulcanizing agent and accelerator were added, filtered, sheeted, placed, and vulcanized to obtain a coupling rubber pad;

[0054] The raw material components of the coupling rubber pad are chloro ether rubber 62 parts, tackifier 2 parts, vulcanizing agent 1 part, accelerator 2.65 parts, scorch retarder 0.45 parts, plasticizer 7.6 parts, antioxidant 0.4 parts, lubricant 2.12 parts, acid absorbent 0.4 parts, and carbon black 19 parts, by weight;

[0055] The vulcanizing agent is trithiocyanuric acid, the scorch retarder is N-cyclohexylthiophthalimide, the antioxidant is nickel dibutyldithiocarbamate, and the acid absorbent is zeolite;

[0056] The accelerator is magnesium oxide and triallyl isocyanurate, which are compounded at a mass ratio of 2.5:0.15;

[0057] The plasticizer is di[2-(2-butoxyethoxy)ethyl] adipate, paraffin oil, and dioctyl sebacate, which are compounded at a mass ratio of 5.5:1.5:0.6;

[0058] The lubricant is glyceryl stearate, stearic amide, stearic acid, dioctyl phthalate, and triethyl citrate, which are compounded at a mass ratio of 0.15:0.35:1.5:0.06:0.06;

[0059] The tackifier is rosin and composite rosin, which are compounded at a mass ratio of 1:1, and the preparation of the composite rosin comprises the following steps:

[0060] 1) Under a nitrogen atmosphere, 3.34 g of hydrogenated rosin, 1.4 g of glycidyl methacrylate, 3 mg of p-hydroxyanisole, and 6 mg of triethylamine were mixed, heated to 86°C for 2.5 h, then heated to 118°C for 3.5 h to obtain a hydrogenated rosin-based acrylate resin;

[0061] 2) Under nitrogen atmosphere, mix 2 g polytetrahydrofuran, 0.71 g isophorone diisocyanate, 0.14 g toluene-2, 4-diisocyanate, 5 mL N, N-dimethylacetamide, 5.7 mg dibutyltin dilaurate, stir at 58 °C for 60 min, add 0.17 g adipic acid dihydrazide, 5 mL N, N-dimethylacetamide, warm up to 118 °C, keep for 5.5 h, add 0.37 g 2- (tert-butylamino) ethyl methacrylate, keep for 25 min, to obtain double bond terminated poly (urethane-urea) ;

[0062] 3) Mix 4.2 g hydrogenated rosin based acrylate resin, 1.8 g double bond terminated poly (urethane-urea), 1.2 g 3-acrylamidophenylboronic acid, 30 mL N, N-dimethylformamide, add 0.08 g photoinitiator, warm up to 55 °C, irradiate under 365 nm light for 5.5 h, centrifuge, wash, dry, to obtain composite rosin;

[0063] The carbon black is modified by the following preparation steps:

[0064] (1) Mix 134 mg vinyltrimethylsilane, 20 mL anhydrous ethanol, 2 mL acetic acid, stir for 35 min, add 60 mL anhydrous ethanol, 2 g carbon black, ultrasonic treatment for 35 min, warm up to 78 °C, keep for 4.5 h under stirring, centrifuge, wash, dry, to obtain double bond modified carbon black;

[0065] (2) Mix 1.5 g double bond modified carbon black, 0.3 g salicylaldehyde derivative containing double bond and ammonium, 20 mL N, N-dimethylformamide, add 0.02 g photoinitiator, warm up to 45 °C, irradiate under 365 nm light for 5.5 h, centrifuge, wash, dry, to obtain modified carbon black;

[0066] The preparation of salicylaldehyde derivative containing double bond and ammonium includes the following steps:

[0067] A. Under nitrogen atmosphere, mix 5.2 mL 2- (dimethylamino) ethyl methacrylate, 16 mL acetone, stir at 0 °C for 8-12 min, add 5.4 g 5- (chloromethyl) -2-hydroxybenzaldehyde, 4 mL acetone, keep for 4.5 h, filter, recrystallize, dry, to obtain N- (3-aldehyde-4-hydroxybenzyl) -2- (methacryloyloxy) -N, N-dimethyl ethyl-1- ammonium chloride;

[0068] B. Under nitrogen atmosphere, 1 mmol of N-(3-formyl-4-hydroxybenzyl)-2-(methacryloyloxy)-N,N-dimethylethyl-1- ammonium chloride, 4 mL of methanol, 1 mmol of 3,4-dihydroxybenzohydrazide were mixed, and the mixture was stirred at 20°C for 11.5 h, vacuum rotary evaporation, recrystallization, and drying to obtain a salicylaldehyde derivative containing a double bond and an ammonium group.

[0069] Example 3: A preparation method of a coupling rubber pad, comprising the following steps:

[0070] The chloro ether rubber is put into a mixer, then tackifier, scorch retarder, plasticizer, antioxidant, lubricant, acid absorber, and carbon black are sequentially added, mixing, sheeting, cooling and standing, then vulcanizing agent and accelerator are added, filtering, sheeting, standing, and vulcanization to obtain a coupling rubber pad;

[0071] The raw material components of the coupling rubber pad are chloro ether rubber 65 parts, tackifier 3 parts, vulcanizing agent 1.5 parts, accelerator 3.2 parts, scorch retarder 0.5 parts, plasticizer 9 parts, antioxidant 0.5 parts, lubricant 2.8 parts, acid absorber 0.5 parts, and carbon black 21 parts by weight;

[0072] The vulcanizing agent is trithiocyanuric acid, the scorch retarder is N-cyclohexylthiophthalimide, the antioxidant is nickel dibutyldithiocarbamate, and the acid absorber is zeolite;

[0073] The accelerator is magnesium oxide and triallyl isocyanurate with a mass ratio of 3:0.2;

[0074] The plasticizer is di[2-(2-butoxyethoxy)ethyl] adipate, paraffin oil, and dioctyl sebacate with a mass ratio of 6:2:1;

[0075] The lubricant is glyceryl stearate, stearic amide, stearic acid, dioctyl phthalate, and triethyl citrate with a mass ratio of 0.2:0.4:2:0.1:0.1;

[0076] The tackifier is rosin and composite rosin with a mass ratio of 1:1, and the preparation of the composite rosin comprises the following steps:

[0077] 1) Under nitrogen atmosphere, 3.34 g of hydrogenated rosin, 1.4 g of glycidyl methacrylate, 3 mg of p-hydroxyanisole, and 6 mg of triethylamine are mixed, heated to 88°C for 2 h, and then heated to 120°C for 3 h to obtain a hydrogenated rosin-based acrylate resin;

[0078] 2) 2 g of polytetrahydrofuran, 0.71 g of isophorone diisocyanate, 0.14 g of toluene-2, 4-diisocyanate, 5 mL of N, N-dimethylacetamide, 5.7 mg of dibutyltin dilaurate were mixed under nitrogen atmosphere, stirred at 60°C for 50 min, a mixture of 0.17 g of adipic acid dihydrazide, 5 mL of N, N-dimethylacetamide was added, the temperature was raised to 120°C, and kept for 5 h, 0.37 g of 2- (tert-butylamino) ethyl methacrylate was added, and kept for 30 min to obtain a double bond-terminated poly (urethane-urea) ;

[0079] 3) 4.2 g of a hydrogenated rosin-based acrylate resin, 1.8 g of a double bond-terminated poly (urethane-urea), 1.2 g of 3-acrylamidophenylboronic acid, 30 mL of N, N-dimethylformamide were mixed, 0.08 g of a photoinitiator was added, the temperature was raised to 60°C, and irradiated under 365 nm light for 5 h, centrifuged, washed, and dried to obtain a composite rosin;

[0080] The carbon black was modified by the following preparation steps:

[0081] (1) 134 mg of vinyltrimethylsilane, 20 mL of anhydrous ethanol, 2 mL of acetic acid were mixed, stirred for 40 min, a mixture of 60 mL of anhydrous ethanol, 2 g of carbon black was added, ultrasonically treated for 40 min, the temperature was raised to 80°C, and kept for 5 h with stirring, centrifuged, washed, and dried to obtain a double bond-modified carbon black;

[0082] (2) 1.5 g of the double bond-modified carbon black, 0.3 g of a salicylaldehyde derivative containing a double bond and an ammonium group, 20 mL of N, N-dimethylformamide were mixed, 0.02 g of a photoinitiator was added, the temperature was raised to 50°C, and irradiated under 365 nm light for 6 h, centrifuged, washed, and dried to obtain a modified carbon black;

[0083] The salicylaldehyde derivative containing a double bond and an ammonium group was prepared by the following steps:

[0084] A. 5.2 mL of 2- (dimethylamino) ethyl methacrylate, 16 mL of acetone were mixed under nitrogen atmosphere, stirred at 0°C for 12 min, a mixture of 5.4 g of 5- (chloromethyl) -2-hydroxybenzaldehyde, 4 mL of acetone was added, kept for 5 h, filtered, recrystallized, and dried to obtain N- (3-aldehyde-4-hydroxybenzyl) -2- (methacryloyloxy) -N, N-dimethyl ethyl-1- ammonium chloride;

[0085] B. Under nitrogen atmosphere, 1 mmol of N-(3-formyl-4-hydroxybenzyl)-2- (methacryloyloxy)-N,N-dimethylethyl-1-aminium chloride, 4 mL of methanol were mixed, and a mixture of 4 mL of methanol, 1 mmol of 3,4-dihydroxybenzohydrazide was added. The mixture was stirred at 25 °C for 11 h, vacuum rotary evaporation, recrystallization, and drying to obtain a salicylaldehyde derivative containing a double bond and an ammonium group.

[0086] Comparative Example 1: As a control group, the modified carbon black was replaced with carbon black, and the other procedures were normal.

[0087] Comparative Example 2: As a control group, no double bond capping poly (urethane-urea) was added when preparing the composite rosin, and the other procedures were normal.

[0088] In the examples and comparative examples, the chloroether rubber was a copolymer chloroether rubber and a homopolymer chloroether rubber compounded at a mass ratio of 2:1.

[0089] The sources of the raw materials used (only exemplary) are as follows:

[0090] Copolymer chloroether rubber ECO (C2000L): Japan Zeon; homopolymer chloroether rubber CO (H-50): Wuhan Organic Chemical Co., Ltd.; trimer thiocyanic acid S49411, paraffin oil S68179: Shanghai Yuan Ye Biological Technology Co., Ltd.; carbon black N330: Wuhan Jiyesheng Chemical Co., Ltd.; rosin HC4756: Tianmen Hengchang Chemical Co., Ltd.; hydrogenated rosin (acid value 168 mgKOH / g, softening point 80 °C), photoinitiator 1173 (2-hydroxy-2-methylpropiophenone): commercially available; polytetrahydrofuran P118599, isophorone diisocyanate I109582, toluene-2,4-diisocyanate T135411, adipic acid dihydrazide A109760, 2-(tert-butylamino)ethyl methacrylate B303600, 3-acrylamidophenylboronic acid A188951, 2-(dimethylamino)ethyl methacrylate A168938, 3,4-dihydroxybenzohydrazide D698215: Aladdin Reagent.

[0091] Performance test: The rubber pads prepared in the examples and comparative examples were tested.

[0092] Antibacterial property: the test sample was cut into a sample with a length of 5 mm, a width of 2 mm and a thickness of 1 mm, and the sample was subjected to 30 times of deionized water flushing, each time for 1 min, and then subjected to antibacterial test after being dried, with Escherichia coli as the test bacteria, and a plate method was used for testing; tear strength: determined according to GB / T 529-2008, using a right-angle sample, and the tensile speed was 500 mm / min; acoustic attenuation coefficient: determined according to ASTM E494, using a pulse echo method for acoustic attenuation coefficient test, and the test temperature was 25 DEG C; self-repairing property: the test sample was cut into a sample with a length of 5 mm, a width of 2 mm and a thickness of 1 mm, a 1 mm long, 0.5 mm deep and 4 microns wide scratch was drawn on the surface, then the sample was kept at 60 DEG C for 12 hours, and the length of the scratch was observed by an electron microscope, and the self-repairing rate = (L 初始划痕长度 -L 现有划痕长度 ) / L 初始划痕长度 x 100%; the obtained results are shown in Table 1;

[0093]

[0094] The application provides a coupling rubber pad and a preparation method thereof.

[0095] It can be known from the comparison between Example 3 and Comparative Example 1 that, in the application, carbon black is used as a reinforcing filler, in order to improve the bonding strength of carbon black and the rubber pad base material, the carbon black is modified, that is, the carbon black is double-bonded by using vinyl trimethylsilane, and then a salicylaldehyde derivative containing a double bond and an ammonium radical is grafted by light clicking; the salicylaldehyde derivative containing a double bond and an ammonium radical is prepared from 5- (chloromethyl) -2-hydroxybenzaldehyde as a raw material and 2- (dimethylamino) ethyl methacrylate by reaction to obtain N- (3-aldehyde-4-hydroxybenzyl) -2- (methacryloyloxy) -N, N-dimethyl ethyl-1-ammonium chloride, and then Schiff base reaction with 3, 4-dihydroxybenzoyl hydrazine to prepare; the introduction of the quaternary ammonium salt cation in the salicylaldehyde derivative containing a double bond and an ammonium radical endows the rubber pad with antibacterial property and improves the use safety of the rubber pad; the o-diphenol structure can reversibly react with the phenylboronic acid group in the complex rosin to form a dynamic borate ester bond; through the modification of carbon black and the cooperation of the complex rosin, a multiple crosslinking network integrating covalent bond, dynamic borate ester bond, urethane-urea dynamic bond and hydrogen bond is constructed in the rubber matrix, which greatly improves the internal defects, enables the sound wave energy to pass more efficiently, significantly reduces the scattering loss, improves the stability of the acoustic performance, and the dense crosslinking network and the self-repairing mechanism enable the rubber pad to have excellent mechanical properties and effectively restore the micro-damage generated in use, thereby prolonging the service life of the coupling rubber pad.

[0096] Comparing Example 3 with Comparative Example 2, it can be seen that rosin is used as a tackifier. To improve the chemical stability and durability of the tackifier, a composite rosin compound is introduced as a tackifier. By introducing acrylate groups into the rosin, hydrogenated rosin-based acrylate resin is obtained. Photo-initiated copolymerization is then used to graft double-bond-terminated poly(carbamate-urea) and 3-acrylamidophenylboronic acid to obtain a multifunctional composite rosin. Among them, the double-bond-terminated poly(carbamate-urea) uses polytetrahydrofuran as the soft segment and isophorone as the soft segment. Diisocyanate and toluene-2,4-diisocyanate are used as hard segments, and adipic acid dihydrazide is used as a chain extender to introduce dynamic reversible crosslinking points and multiple hydrogen bonds. 2-(tert-butylamino)ethyl methacrylate reacts with isocyanate groups to further enhance the dynamic crosslinking points, thus preparing a flexible crosslinking agent. The introduction of double-bond-terminated poly(urethane-urea) endows the rubber pad with certain self-healing properties, improving the durability and fatigue resistance of the rubber pad. The introduction of 3-acrylamidophenylboronic acid improves the biocompatibility of the rubber pad.

[0097] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the present invention's specification under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A method for preparing a coupling rubber pad, characterized in that, Includes the following steps: Chlorinated ether rubber is put into a mixer, and then tackifier, anti-scorching agent, plasticizer, antioxidant, lubricant, acid absorber and carbon black are added in sequence. The mixture is then mixed, pressed into sheets, cooled and allowed to stand. Then vulcanizing agent and accelerator are added, filtered, sheeted, allowed to stand, and vulcanized to obtain a coupling rubber pad.

2. The method for preparing a coupling rubber pad according to claim 1, characterized in that, By weight, the raw material components of the coupling rubber pad are: 60-65 parts of chloroprene rubber, 1-3 parts of tackifier, 0.5-1.5 parts of vulcanizing agent, 2.1-3.2 parts of accelerator, 0.4-0.5 parts of anti-scorching agent, 6.5-9 parts of plasticizer, 0.3-0.5 parts of antioxidant, 1.5-2.8 parts of lubricant, 0.3-0.5 parts of acid absorber, and 18-21 parts of carbon black.

3. The method for preparing a coupling rubber pad according to claim 1, characterized in that, The chloroprene rubber is a compound of copolychloroprene rubber and homopolychloroprene rubber in a mass ratio of 2:1; the tackifier is rosin, the vulcanizing agent is trithiocyanate, the scorching inhibitor is N-cyclohexylthiophthalimide, the antioxidant is nickel dibutyldithiocarbamate, and the acid absorber is zeolite.

4. The method for preparing a coupling rubber pad according to claim 1, characterized in that, The accelerator is one or a combination of magnesium oxide and triallyl isocyanurate.

5. The method for preparing a coupling rubber pad according to claim 1, characterized in that, The plasticizer is one or more of the following: di[2-(2-butoxyethoxy)ethyl adipic acid], paraffin oil, and dioctyl sebacate.

6. The method for preparing a coupling rubber pad according to claim 1, characterized in that, The lubricant is a compound of one or more of the following: glyceryl stearate, stearamide, stearic acid, dioctyl phthalate, and triethyl citrate.

7. The method for preparing a coupling rubber pad according to claim 1, characterized in that, The tackifier is obtained by compounding rosin and composite rosin in a mass ratio of 1:

1. The preparation of the composite rosin includes the following steps: 1) Under a nitrogen atmosphere, hydrogenated rosin, glycidyl methacrylate, p-hydroxyanisole, and triethylamine are mixed, heated to 85-88℃ and kept at that temperature for 2-3 hours, and then heated to 115-120℃ and kept at that temperature for 3-4 hours to obtain hydrogenated rosin-based acrylate resin. 2) Under a nitrogen atmosphere, polytetrahydrofuran, isophorone diisocyanate, toluene-2,4-diisocyanate, N,N-dimethylacetamide, and dibutyltin dilaurate are mixed and stirred at 55-60℃ for 50-70 min. A mixture of adipic acid dihydrazide and N,N-dimethylacetamide is added, the temperature is raised to 115-120℃, and the temperature is maintained for 5-6 h. Then, 2-(tert-butylamino)ethyl methacrylate is added, and the temperature is maintained for 20-30 min to obtain double-bond-terminated poly(urethane-urea). 3) Mix hydrogenated rosin-based acrylate resin, double-bond-terminated poly(urethane-urea), 3-acrylamidophenylboronic acid, and N,N-dimethylformamide, add a photoinitiator, heat to 50-60℃, irradiate under 365nm light for 5-6 hours, centrifuge, wash, and dry to obtain composite rosin.

8. The method for preparing a coupling rubber pad according to claim 1, characterized in that, The modification of carbon black includes the following preparation steps: (1) Mix vinyltrimethylsilane, anhydrous ethanol and acetic acid, stir for 30-40 min, add anhydrous ethanol and carbon black mixture, sonicate for 30-40 min, heat to 75-80℃, keep warm for 4-5 h with stirring, centrifuge, wash and dry to obtain double bonded carbon black. (2) Mix double-bonded carbon black, salicylaldehyde derivative containing double bonds and ammonium groups, and N,N-dimethylformamide, add a photoinitiator, heat to 40-50℃, irradiate under 365nm light for 5-6h, centrifuge, wash, and dry to obtain modified carbon black.

9. The method for preparing a coupling rubber pad according to claim 8, characterized in that, The preparation of salicylaldehyde derivatives containing double bonds and ammonium groups includes the following steps: A. Under a nitrogen atmosphere, 2-(dimethylamino)ethyl methacrylate and acetone were mixed and stirred at 0°C for 8-12 min. A mixture of 5-(chloromethyl)-2-hydroxybenzaldehyde and acetone was added, and the mixture was kept at this temperature for 4-5 h. The mixture was then filtered, recrystallized, and dried to obtain N-(3-aldehyde-4-hydroxybenzyl)-2-(methacryloyloxy)-N,N-dimethylethyl-1-ammonium chloride. B. Under a nitrogen atmosphere, N-(3-aldehyde-4-hydroxybenzyl)-2-(methacryloyloxy)-N,N-dimethylethyl-1-ammonium chloride and methanol were mixed, and a mixture of methanol and 3,4-dihydroxybenzoylhydrazine was added. The mixture was stirred at 18-25°C for 11-12 h, dried under vacuum, recrystallized, and dried to obtain a salicylaldehyde derivative containing double bonds and ammonium groups.

10. A coupling rubber pad, characterized in that, Prepared by the method according to any one of claims 1-9.

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