Rubber fender

Abstract

The invention discloses a rubber fender, and relates to the technical field of rubber products. The rubber fender prepared by the invention comprises composite rubber, modified calcium carbonate, a vulcanizing agent, a plasticizer and a stabilizer, the composite rubber comprises modified polyurethane rubber and modified ethylene propylene diene monomer, the modified polyurethane rubber is prepared by reacting polycaprolactone polyol with an isocyanate derivative, and the polycaprolactone polyol is 1, 2, 4-trimethyl-1, 3-pentanediol monoisobutyrate. The composite rubber is prepared by reacting 1, 4-butanediol diacrylate with sulfydryl polycaprolactone, so that the strength and wear resistance of the composite rubber are improved; the modified calcium carbonate is prepared by coating the surface of calcium carbonate with adipic acid and then reacting with phosphoric acid silicone oil, and the phosphoric acid silicone oil is prepared by crosslinking epoxy polyether silicone oil and amino silicone oil and then reacting with dioctyl dithiophosphoric acid, so that the wear resistance of the rubber is further improved, the overall strength of the product is enhanced, and the rubber fender has excellent performance.

Description

Technical Field

[0001] The present invention relates to the technical field of rubber products, and particularly to a rubber fender. Background Art

[0002] A rubber fender is an elastic buffer device installed on a wharf or a ship, mainly used to absorb the collision energy between a ship and a wharf or other ships during berthing or mooring, and to protect the ship and the wharf structure from damage. Generally, rubber fenders can be divided into two categories according to their structures: solid rubber fenders (non-floating type) and floating rubber fenders. Solid rubber fenders (non-floating type) are wharf ship anti-collision devices with an earlier application history and a wide application range. According to the force-bearing situation of rubber fenders, they can be divided into shear type, rotation type, compression type, etc.

[0003] Solid rubber fenders have high energy absorption and reaction force, and at the same time have the advantages of low cost, simple installation and maintenance, etc., and are protective devices installed more on wharves and shipyards. However, the rubber fenders prepared by rubber vulcanization molding often have poor strength and wear resistance, which affects the service life of rubber fenders. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a rubber fender.

[0005] A technical solution proposed by the present invention to solve the above technical problem is: a rubber fender, comprising composite rubber, modified calcium carbonate, vulcanizing agent, plasticizer and stabilizer; the composite rubber comprises modified polyurethane rubber and modified ethylene propylene diene monomer rubber.

[0006] Preferably, the modified polyurethane rubber is prepared by reacting polycaprolactone polyol with an isocyanate derivative; the polycaprolactone polyol is prepared by reacting 1,4-butanediol diacrylate with mercapto polycaprolactone; the isocyanate derivative is prepared by reacting dicyclopentadiene with hexamethylene diisocyanate.

[0007] Preferably, the modified ethylene propylene diene monomer rubber is prepared by grafting maleic anhydride onto ethylene propylene diene monomer rubber.

[0008] Preferably, the modified calcium carbonate is prepared by coating the surface of calcium carbonate with adipic acid and then reacting with phosphosilicone oil; the phosphosilicone oil is prepared by crosslinking epoxy polyether silicone oil and amino silicone oil and then reacting with dioctyl dithiophosphoric acid.

[0009] Preferably, the vulcanizing agent is zinc oxide, magnesium oxide or lead tetraoxide; the plasticizer is dipropylene glycol; the stabilizer is antioxidant 4010.

[0010] Preferably, the preparation method of the rubber fender comprises the following specific steps: S1. Under a nitrogen atmosphere, mix 1,4-butanediol diacrylate, mercapto polycaprolactone, triethylamine dichloromethane in a mass ratio of 1:2.2 - 2.4:0.03 - 0.05:50. Cool down to 8 - 10 °C, react for 30 - 50 min, conduct vacuum distillation, and dry in vacuum at 50 - 60 °C to obtain polycaprolactone polyol; S2. Mix the polycaprolactone polyol preheated to 60 - 80 °C, the isocyanate derivative preheated to 70 - 80 °C and the chain extender 1,4-butanediol in a mass ratio of 100:10 - 13:3. React at 60 - 80 °C for 1 - 2 h. Add modified ethylene propylene diene monomer rubber which is 0.2 - 0.4 times the mass of the polycaprolactone polyol, stir evenly and transfer to an oven. Bake at 140 - 160 °C for 8 - 12 h. After cooling, place it in the oven and conduct secondary curing at 110 - 120 °C for 2 - 4 h to obtain the composite rubber; S3. Mix epoxy polyether silicone oil, amino silicone oil and isopropanol in a mass ratio of 1.8 - 2:1:8 - 10. Heat up to 70 - 75 °C and react for 5 - 6 h. Conduct vacuum distillation, transfer to a reaction kettle. Under a nitrogen atmosphere, add dioctyl dithiophosphate which is 0.1 - 0.14 times the mass of the epoxy polyether silicone oil, heat up to 95 - 105 °C and react for 6 - 8 h. Conduct vacuum distillation to obtain phosphosilicone oil; S4. Mix calcium carbonate and deionized water in a mass ratio of 1:50 - 80, stir evenly, add adipic acid which is 2 - 3 times the mass of the calcium carbonate, heat up to 70 - 72 °C and react for 50 - 70 min. Filter and wash with deionized water for 3 - 5 times, then disperse in phosphosilicone oil which is 8 - 10 times the mass of the calcium carbonate, stir evenly and heat up to 120 - 140 °C, stir and react at 800 - 1200 rpm for 60 - 90 min. Cool down to 50 - 60 °C, filter and crush, and dry at 40 - 45 °C to obtain modified calcium carbonate; S5. Place the composite rubber in a mixer for stage plasticizing, add modified calcium carbonate, vulcanizing agent, plasticizer and stabilizer, and continue mixing. The mixing temperature is 90 - 110 °C and the time is 3 - 5 min. The mass ratio of the composite rubber, modified calcium carbonate, vulcanizing agent, plasticizer and stabilizer is 70 - 100:20 - 40:4 - 6:0.5 - 2.5:0.5 - 1.5. After mixing, transfer to an open mill for rolling, then press into sheets with a calender, cut according to the fender size, and vulcanize at 160 - 170 °C to obtain the rubber fender.

[0011] Preferably, in the above step S1, the preparation method of mercapto polycaprolactone is as follows: Mix ε-caprolactone, stannous trifluoromethanesulfonate, toluene, and tetrahydrofuran in a mass ratio of 5:0.1~0.2:8:2, react at room temperature for 20~40 min, then add mercaptoethanol in an amount of 0.06~0.09 times the mass of ε-caprolactone, mix evenly, and perform 3~5 cycles of liquid nitrogen cooling, vacuum pumping, and thawing operations, then vacuum seal and react for 12~14 h. Add trichloromethane with the same mass as ε-caprolactone, stir evenly, precipitate with methanol, filter by suction, and finally dry in vacuum to obtain mercapto polycaprolactone.

[0012] Preferably, in the above step S2, the preparation method of the isocyanate derivative is as follows: Mix dicyclopentadiene, hexamethylene diisocyanate, and tetrahydrofuran in a mass ratio of 1:2~3:20, stir evenly, heat up to 90~110 °C, add dibutyltin dilaurate as a catalyst in an amount of 0.02~0.04 times the mass of dicyclopentadiene, react for 4~6 h, perform vacuum distillation, and dry in vacuum at 50~60 °C to obtain the isocyanate derivative.

[0013] Preferably, in S2, the preparation method of the modified ethylene-propylene-diene monomer rubber is as follows: Mix ethylene-propylene-diene monomer rubber and styrene, stir evenly, then add maleic anhydride, initiator dicumyl peroxide, and hexamethylphosphoric triamide, mix evenly, and use a twin-screw extruder to melt extrude, pelletize, and dry to obtain the modified ethylene-propylene-diene monomer rubber. The mass ratio of ethylene-propylene-diene monomer rubber, styrene, maleic anhydride, initiator dicumyl peroxide, and hexamethylphosphoric triamide is 90~100:2~3:1~3:0.2~0.4:0.4~0.8. The extrusion temperature of the twin-screw extruder is 240~280 °C, the residence time is 3~6 min, the pressure is 12~18 MPa, the temperature of the first zone is 140~145 °C, the temperature of the second zone is 140~150 °C, the temperature of the third zone is 150~160 °C, the temperature of the fourth zone is 145~155 °C, and the temperature of the die head is 150~160 °C.

[0014] Preferably, in the above step S3, the preparation method of epoxy polyether silicone oil is as follows: Mix hydrogen-containing silicone oil, allyl polyether, allyl epoxy polyether, and isopropanol in a mass ratio of 10:8~12:0.5~0.6:5, stir evenly, heat up to 90~92 °C, react for 3~4 h, then dropwise add a 2% solution of chloroplatinic acid in isopropanol with a mass fraction of 0.05~0.1 times the mass of hydrogen-containing silicone oil at a rate of 1~3 ml / min, cool down to 70~72 °C, continue to react for 3~4 h, perform vacuum distillation, and dry in vacuum at 50~60 °C to obtain epoxy polyether silicone oil.

[0015] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: The rubber fender prepared by the present invention comprises a thermoplastic elastomer, a branched polyolefin, a modified tackifying resin, and an additive; The rubber fender prepared by the present invention comprises composite rubber, modified calcium carbonate, vulcanizing agent, plasticizer and stabilizer. The composite rubber includes modified polyurethane rubber and modified ethylene propylene diene monomer (EPDM) rubber. The modified polyurethane rubber is prepared by reacting polycaprolactone polyol with isocyanate derivative. The polycaprolactone polyol is prepared by reacting 1,4-butanediol diacrylate with mercapto polycaprolactone. The isocyanate derivative is prepared by reacting dicyclopentadiene with hexamethylene diisocyanate. The modified EPDM rubber is prepared by grafting maleic anhydride onto EPDM rubber. The modified polyurethane rubber prepared by reacting polycaprolactone polyol with isocyanate derivative has a polycaprolactone structure introduced into the molecular chain. At the same time, the maleic anhydride-grafted EPDM rubber has good interfacial bonding ability, so that the modified polyurethane rubber and the modified EPDM rubber have good biocompatibility, improving the strength and wear resistance of the composite rubber. The modified calcium carbonate is prepared by coating the surface of calcium carbonate with adipic acid and then reacting with phosphosilicone oil. The phosphosilicone oil is prepared by crosslinking epoxy polyether silicone oil and amino silicone oil and then reacting with dioctyl dithiophosphoric acid. Introducing the modified calcium carbonate into the composite rubber enhances the filling property and hardness of the rubber. By double coating adipic acid and phosphosilicone oil on the surface of calcium carbonate, not only the dispersibility of the filler and the bonding force with the composite rubber are improved, but also the wear resistance of the rubber is further enhanced, and the overall strength of the product is increased, making the rubber fender have excellent performance. Specific embodiments

[0016] The present invention will be specifically described below through examples. It is necessary to point out here that the following examples are only used to further illustrate the present invention and cannot be construed as limiting the protection scope of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention according to the above content of the present invention. Unless otherwise defined, all professional and scientific terms used herein have the same meaning as those familiar to those skilled in the art.

[0017] In order to more clearly illustrate the method provided by the present invention, the following examples are used for detailed description. The test methods for each index of the rubber fenders prepared in the examples and comparative examples are as follows: Tensile properties: The rubber fenders prepared in the examples and comparative examples are tested for tensile strength and elongation at break with reference to ASTM D412-16.

[0018] Tear strength: The rubber fenders prepared in the examples and comparative examples are tested for tear strength with reference to ASTM D624-00.

[0019] Wear resistance: The rubber fenders prepared in the examples and comparative examples are tested for abrasion index with reference to ISO 4649. Example 1

[0020] The preparation method of the rubber fender in this embodiment is as follows: S1. Mix ε-caprolactone, stannous trifluoromethanesulfonate, toluene, and tetrahydrofuran in a mass ratio of 5:0.1:8:2. After reacting at room temperature for 20 min, add mercaptoethanol with a mass 0.06 times that of ε-caprolactone, mix evenly, and perform 3 cycles of liquid nitrogen cooling, vacuum pumping, and thawing operations. Then, seal it under vacuum and react for 12 h. Add trichloromethane with the same mass as ε-caprolactone, stir evenly, precipitate with methanol, filter by suction, and finally dry under vacuum to obtain mercapto polycaprolactone. Under a nitrogen atmosphere, mix 1,4-butanediol diacrylate, mercapto polycaprolactone, triethylamine dichloromethane in a mass ratio of 1:2.2:0.03:50, cool down to 8 °C, react for 30 min, perform vacuum distillation, and dry under vacuum at 50 °C to obtain polycaprolactone polyol; S2. Mix ethylene propylene diene monomer (EPDM) and styrene, stir evenly, then add maleic anhydride, initiator dicumyl peroxide, and hexamethylphosphoric triamide. After mixing evenly, use a twin-screw extruder to melt extrude, pelletize, and dry to obtain modified EPDM. The mass ratio of EPDM, styrene, maleic anhydride, initiator dicumyl peroxide, and hexamethylphosphoric triamide is 90:2:1:0.2:0.4. The extrusion temperature of the twin-screw extruder is 240 °C, the residence time is 3 min, the pressure is 12 MPa, the temperature of the first zone is 140 °C, the temperature of the second zone is 140 °C, the temperature of the third zone is 150 °C, the temperature of the fourth zone is 145 °C, and the temperature of the die head is 150 °C. Mix dicyclopentadiene, hexamethylene diisocyanate, and tetrahydrofuran in a mass ratio of 1:2:20, stir evenly, heat up to 90 °C, add dibutyltin dilaurate as a catalyst with a mass 0.02 times that of dicyclopentadiene, react for 4 h, perform vacuum distillation, and dry under vacuum at 50 °C to obtain an isocyanate derivative. Mix the preheated polycaprolactone polyol at 60 °C, the preheated isocyanate derivative at 70 °C, and the chain extender 1,4-butanediol in a mass ratio of 100:10:3, react at 60 °C for 1 h, add modified EPDM with a mass 0.2 times that of polycaprolactone polyol, stir evenly, transfer to an oven, bake at 140 °C for 8 h, cool, and then place in the oven for secondary curing at 1100 °C for 2 h to obtain a composite rubber; S3. Mix hydrogen-containing silicone oil, allyl polyether, allyl epoxy polyether and isopropanol in a mass ratio of 10:8:0.5:5. After stirring evenly, heat up to 90 °C. After reacting for 3 h, dropwise add an isopropanol solution of chloroplatinic acid with a mass fraction of 2% and a mass of 0.05 of the hydrogen-containing silicone oil at a rate of 1 ml / min. Cool down to 70 °C and continue to react for 3 h. Then carry out vacuum distillation and vacuum dry at 50 °C to obtain epoxy polyether silicone oil; Mix epoxy polyether silicone oil, amino silicone oil and isopropanol in a mass ratio of 1.8:1:8, heat up to 70 °C, react for 5 h, carry out vacuum distillation, transfer to a reaction kettle, and under a nitrogen atmosphere, add dioctyl dithiophosphoric acid with a mass 0.1 times that of the epoxy polyether silicone oil, heat up to 95 °C, react for 6 h, and carry out vacuum distillation to obtain phosphoric acid silicone oil; S4. Mix calcium carbonate and deionized water in a mass ratio of 1:50, stir evenly, add adipic acid with a mass twice that of the calcium carbonate, heat up to 70 °C, react for 50 min, filter and wash with deionized water 3 times, then disperse in phosphoric acid silicone oil with a mass 8 times that of the calcium carbonate, stir evenly and heat up to 120 °C, stir and react at 800 rpm for 60 min, cool down to 50 °C, filter and crush, and dry at 40 °C to obtain modified calcium carbonate; S5. Carry out segmented plasticizing of the composite rubber in a mixer, add modified calcium carbonate, vulcanizing agent, plasticizer and stabilizer, and continue mixing. The mixing temperature is 90 °C and the time is 3 min. The mass ratio of the composite rubber, modified calcium carbonate, vulcanizing agent zinc oxide, plasticizer and dipropylene glycol stabilizer antioxidant 4010 is 70:20:4:0.5:0.5. After mixing, transfer to an open mill for remixing, then press into sheets with a calender, cut according to the fender size, and vulcanize at 160 °C to obtain a rubber fender. Example 2

[0021] The preparation method of the rubber fender in this example is as follows: S1. Mix ε-caprolactone, stannous trifluoromethanesulfonate, toluene and tetrahydrofuran in a mass ratio of 5:0.15:8:2. After reacting at room temperature for 30 min, add mercaptoethanol with a mass 0.08 times that of the ε-caprolactone, mix evenly and carry out 4 cycles of liquid nitrogen cooling, vacuum pumping and thawing operations, then vacuum seal and react for 13 h. Add trichloromethane with the same mass as the ε-caprolactone, stir evenly, precipitate with methanol and filter by suction, and finally vacuum dry to obtain mercapto polycaprolactone; Under a nitrogen atmosphere, mix 1,4-butanediol diacrylate, mercapto polycaprolactone, triethylamine dichloromethane in a mass ratio of 1:2.3:0.04:50, cool down to 9 °C, react for 40 min, carry out vacuum distillation, and vacuum dry at 50 - 60 °C to obtain polycaprolactone polyol; S2. Mix ethylene propylene diene monomer (EPDM) with styrene, and after stirring evenly, add maleic anhydride, initiator dicumyl peroxide, and hexamethylphosphoric triamide. After mixing evenly, use a twin-screw extruder to melt, extrude, pelletize, and dry to obtain modified EPDM. The mass ratio of EPDM, styrene, maleic anhydride, initiator dicumyl peroxide, and hexamethylphosphoric triamide is 95:2.5:2:0.3:0.6. The extrusion temperature of the twin-screw extruder is 260 °C, the residence time is 5 min, the pressure is 16 MPa, the temperature of the first zone is 143 °C, the temperature of the second zone is 145 °C, the temperature of the third zone is 155 °C, the temperature of the fourth zone is 150 °C, and the temperature of the die head is 155 °C; Mix dicyclopentadiene, hexamethylene diisocyanate, and tetrahydrofuran in a mass ratio of 1:2.5:20, stir evenly and then heat up to 100 °C, add dibutyltin dilaurate as a catalyst in an amount of 0.03 times the mass of dicyclopentadiene, react for 5 h, carry out vacuum distillation under reduced pressure, and dry in vacuum at 55 °C to obtain an isocyanate derivative; Mix preheated polycaprolactone polyol at 70 °C, preheated isocyanate derivative at 75 °C, and chain extender 1,4-butanediol in a mass ratio of 100:11.5:3, react at 70 °C for 1.5 h, add modified EPDM in an amount of 0.3 times the mass of polycaprolactone polyol, stir evenly and transfer to an oven, bake at 150 °C for 10 h, cool and then place in the oven for secondary curing at 115 °C for 3 h to obtain a composite rubber; S3. Mix hydrogen-containing silicone oil, allyl polyether, allyl epoxy polyether, and isopropanol in a mass ratio of 10:10:0.55:5, stir evenly and then heat up to 91 °C. After reacting for 3.5 h, dropwise add an isopropanol solution of chloroplatinic acid with a mass fraction of 2% and an amount of 0.08 times the mass of hydrogen-containing silicone oil at a rate of 2 ml / min. Cool down to 71 °C and continue to react for 3.5 h. Carry out vacuum distillation under reduced pressure and dry in vacuum at 55 °C to obtain epoxy polyether silicone oil; Mix epoxy polyether silicone oil, amino silicone oil, and isopropanol in a mass ratio of 1.9:1:9, heat up to 73 °C, react for 5.5 h, carry out vacuum distillation under reduced pressure, transfer to a reaction kettle, and under a nitrogen atmosphere, add dioctyl dithiophosphate in an amount of 0.12 times the mass of epoxy polyether silicone oil, heat up to 100 °C, react for 7 h, carry out vacuum distillation under reduced pressure to obtain phosphoric acid silicone oil; S4. Mix calcium carbonate and deionized water in a mass ratio of 1:65, stir evenly, add adipic acid in an amount of 2.5 times the mass of calcium carbonate, heat up to 71 °C, react for 60 min, filter and wash with deionized water 4 times, and then disperse in phosphoric acid silicone oil with a mass 9 times that of calcium carbonate, stir evenly and heat up to 130 °C, stir and react at 1000 rpm for 75 min, cool down to 55 °C, filter and crush, and dry at 43 °C to obtain modified calcium carbonate; S5. The composite rubber is subjected to stepwise plasticizing in a Banbury mixer, and modified calcium carbonate, vulcanizing agent, plasticizer, and stabilizer are added, followed by continuous mixing. The mixing temperature is 100 °C and the time is 4 min. The mass ratio of the composite rubber, modified calcium carbonate, lead tetraoxide as the vulcanizing agent, dipropylene glycol as the plasticizer, and antioxidant 4010 as the stabilizer is 85:30:5:1.8:1. After mixing, it is transferred to an open mill for refining, then pressed into sheets using a calender, cut according to the fender size, and vulcanized at 165 °C to obtain the rubber fender. Example 3

[0022] In this example, the preparation method of the rubber fender is as follows: S1. ε-Caprolactone, stannous trifluoromethanesulfonate, toluene, and tetrahydrofuran are mixed in a mass ratio of 5:0.2:8:2, and reacted at room temperature for 40 min. Then, mercaptoethanol with a mass 0.09 times that of ε-caprolactone is added, and after mixing evenly, 3 - 5 cycles of liquid nitrogen cooling, vacuum pumping, and thawing operations are carried out, and then vacuum sealed and reacted for 14 h. Chloroform with the same mass as ε-caprolactone is added, and after stirring evenly, it is precipitated with methanol and filtered by suction. Finally, it is dried under vacuum to obtain mercapto polycaprolactone; under a nitrogen atmosphere, 1,4-butanediol diacrylate, mercapto polycaprolactone, triethylamine dichloromethane are mixed in a mass ratio of 1:2.4:0.05:50, cooled to 10 °C, and reacted for 50 min, then subjected to vacuum distillation and vacuum dried at 60 °C to obtain polycaprolactone polyol; S2. Ethylene propylene diene monomer rubber and styrene are mixed, and after stirring evenly, maleic anhydride, initiator dicumyl peroxide, and hexamethylphosphoric triamide are added. After mixing evenly, it is melt extruded, pelletized, and dried using a twin-screw extruder to obtain modified ethylene propylene diene monomer rubber. The mass ratio of ethylene propylene diene monomer rubber, styrene, maleic anhydride, initiator dicumyl peroxide, and hexamethylphosphoric triamide is 100:3:3:0.04:0.8. The extrusion temperature of the twin-screw extruder is 280 °C, the residence time is 6 min, the pressure is 18 MPa, the temperature of the first zone is 145 °C, the temperature of the second zone is 150 °C, the temperature of the third zone is 160 °C, the temperature of the fourth zone is 155 °C, and the temperature of the die head is 160 °C; dicyclopentadiene, hexamethylene diisocyanate, and tetrahydrofuran are mixed in a mass ratio of 1:3:20, and after stirring evenly, the temperature is raised to 110 °C, and catalyst dibutyltin dilaurate with a mass 0.02 - 0.04 times that of dicyclopentadiene is added, and reacted for 6 h, then subjected to vacuum distillation and vacuum dried at 60 °C to obtain an isocyanate derivative; preheated polycaprolactone polyol at 80 °C, preheated isocyanate derivative at 80 °C, and chain extender 1,4-butanediol are mixed in a mass ratio of 100:13:3, and reacted at 80 °C for 2 h. Modified ethylene propylene diene monomer rubber with a mass 0.2 - 0.4 times that of polycaprolactone polyol is added, and after stirring evenly, it is transferred to an oven and baked at 160 °C for 12 h. After cooling, it is placed in the oven and secondarily cured at 120 °C for 4 h to obtain the composite rubber; S3. Mix hydrogen-containing silicone oil, allyl polyether, allyl epoxy polyether, and isopropyl alcohol in a mass ratio of 10:12:0.6:5. After stirring evenly, heat it up to 92 °C. After reacting for 4 h, dropwise add an isopropyl alcohol solution of chloroplatinic acid with a mass fraction of 2% and a mass of 0.1% of the hydrogen-containing silicone oil at a rate of 3 ml / min. Cool down to 72 °C and continue reacting for 4 h. Then, perform vacuum distillation and dry it in a vacuum at 60 °C to obtain epoxy polyether silicone oil. Mix epoxy polyether silicone oil, amino silicone oil, and isopropyl alcohol in a mass ratio of 2:1:10. Heat it up to 75 °C and react for 6 h. Perform vacuum distillation, transfer it to a reaction kettle, and under a nitrogen atmosphere, add dioctyl dithiophosphate with a mass 0.14 times that of the epoxy polyether silicone oil. Heat it up to 105 °C and react for 8 h. Perform vacuum distillation to obtain phosphoric acid silicone oil. S4. Mix calcium carbonate and deionized water in a mass ratio of 1:80. Stir evenly, add adipic acid with a mass 3 times that of the calcium carbonate, heat it up to 72 °C, react for 70 min, filter and wash it with deionized water 5 times. Then, disperse it in phosphoric acid silicone oil with a mass 10 times that of the calcium carbonate, stir evenly, heat it up to 140 °C, stir and react at 1200 rpm for 90 min. Cool down to 60 °C, filter and crush it, and dry it at 45 °C to obtain modified calcium carbonate. S5. Place the composite rubber in a mixer for stage plasticization, add modified calcium carbonate, vulcanizing agent, plasticizer, and stabilizer, and continue mixing. The mixing temperature is 110 °C and the time is 5 min. The mass ratio of the composite rubber, modified calcium carbonate, vulcanizing agent lead tetraoxide, plasticizer dipropylene glycol, and stabilizer antioxidant 4010 is 100:40:6:2.5:1.5. After mixing, transfer it to an open mill for rolling, then use a calender to press it into sheets, cut it according to the fender size, and vulcanize it at 170 °C to obtain a rubber fender.

[0023] Comparative Example 1 The preparation method of Comparative Example 1 is the same as that of Example 2. The difference between this rubber fender and that of Example 2 is that the modified polyurethane rubber in this comparative example is prepared by reacting polycaprolactone polyol with hexamethylene diisocyanate.

[0024] Comparative Example 2 The preparation method of Comparative Example 2 is the same as that of Example 2. The difference between this rubber fender and that of Example 2 is that the composite rubber in this comparative example is only modified ethylene propylene diene monomer rubber.

[0025] Comparative Example 3 The preparation method of Comparative Example 3 is the same as that of Example 2. The difference between this rubber fender and that of Example 2 is that the modified polyurethane rubber in this comparative example is prepared by reacting propylene glycol with isocyanate derivatives.

[0026] Comparative Example 4 The preparation method of Comparative Example 4 is the same as that of Example 2. The difference between this rubber fender and that of Example 2 is that for the rubber fender prepared in this comparative example, the modified calcium carbonate is obtained by coating the surface of calcium carbonate with adipic acid.

[0027] Comparative Example 5 The preparation method of Comparative Example 5 is the same as that of Example 2. The difference between this rubber fender and that of Example 2 is that for the rubber fender prepared in this comparative example, the modified calcium carbonate is obtained by coating the surface of calcium carbonate with adipic acid and then reacting with amino silicone oil.

[0028] Effect Example Table 1 below shows the performance test results of the rubber fenders prepared in the examples and comparative examples; Table 1 <![CDATA[Tensile strength (kg / cm2)]]> Elongation at break (%) Tear strength (kN / m) Wear coefficient (%) Example 1 187 316 35.4 92.27 Example 2 188 329 36.2 92.94 Example 3 184 310 33.7 90.35 Comparative Example 1 175 305 29.1 90.13 Comparative Example 2 172 302 28.3 91.00 Comparative Example 3 170 300 28.0 90.21 Comparative Example 4 175 301 28.9 80.53 Comparative Example 5 171 296 28.1 80.67 From the comparison of the performance data in Table 1, it can be seen that the rubber fender prepared by the present invention has wear resistance, stability and adhesiveness; From the comparison of the experimental data of Example 1, Example 2, Example 3 and Comparative Example 1, Comparative Example 2, Comparative Example 3, it can be found that the modified polyurethane rubber prepared by reacting polycaprolactone polyol with isocyanate derivative has a polycaprolactone structure introduced into the molecular chain, and at the same time, the maleic anhydride grafted ethylene propylene diene monomer rubber has good interfacial binding ability, so that the modified polyurethane rubber and the modified ethylene propylene diene monomer rubber have good biocompatibility, and the strength and wear resistance of the composite rubber are improved.

[0029] From the comparison of the experimental data of Example 1, Example 2, Example 3 and Comparative Example 4, Comparative Example 5, it can be found that introducing modified calcium carbonate into the composite rubber enhances the filling property and hardness of the rubber. By double coating adipic acid and phosphosilicone oil on the surface of calcium carbonate, not only the dispersibility of the filler and the binding force with the composite rubber are improved, but also the wear resistance of the rubber is further enhanced, and the overall strength of the product is increased, making the rubber fender have excellent performance.

[0030] Obviously, the above embodiments are only examples for clearly illustrating the embodiments of the present invention, rather than limitations on the embodiments of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. And these obvious changes or modifications derived from the spirit of the present invention are still within the protection scope of the present invention.

Claims

1. A rubber fender, characterized in that, It includes composite rubber, modified calcium carbonate, vulcanizing agent, plasticizer and stabilizer; the composite rubber includes modified polyurethane rubber and modified ethylene propylene diene monomer (EPDM) rubber.

2. A rubber fender according to claim 1, characterized in that, The modified polyurethane rubber is prepared by reacting polycaprolactone polyol with isocyanate derivative; the polycaprolactone polyol is prepared by reacting 1,4-butanediol diacrylate with mercapto polycaprolactone; the isocyanate derivative is prepared by reacting dicyclopentadiene with hexamethylene diisocyanate.

3. A rubber fender according to claim 1, characterized in that, The modified EPDM rubber is prepared by grafting maleic anhydride onto EPDM rubber.

4. A rubber fender according to claim 1, characterized in that, The modified calcium carbonate is prepared by coating the surface of calcium carbonate with adipic acid and then reacting with phosphosilicone oil; the phosphosilicone oil is prepared by crosslinking epoxy polyether silicone oil and amino silicone oil and then reacting with dioctyl dithiophosphoric acid.

5. A rubber fender according to claim 1, characterized in that, The vulcanizing agent is zinc oxide, magnesium oxide or lead tetraoxide; the plasticizer is dipropylene glycol; the stabilizer is antioxidant 4010.

6. The preparation method of a rubber fender according to claim 1, characterized in that, It includes the following specific steps: S1. Under a nitrogen atmosphere, mix 1,4-butanediol diacrylate, mercapto polycaprolactone, triethylamine dichloromethane in a mass ratio of 1:2.2~2.4:0.03~0.05:50, cool down to 8~10 °C, react for 30~50 min, carry out vacuum distillation, and dry in vacuum at 50~60 °C to obtain polycaprolactone polyol. S2. Mix the polycaprolactone polyol preheated to 60~80 °C, the isocyanate derivative preheated to 70~80 °C and the chain extender 1,4-butanediol in a mass ratio of 100:10~13:3, react at 60~80 °C for 1~2 h, add modified EPDM rubber in an amount of 0.2~0.4 times the mass of the polycaprolactone polyol, stir evenly, transfer to an oven, bake at 140~160 °C for 8~12 h, cool and then place in the oven for secondary curing at 110~120 °C for 2~4 h to obtain the composite rubber. S3. Mix epoxy polyether silicone oil, amino silicone oil and isopropanol in a mass ratio of 1.8~2:1:8~10, heat up to 70~75 °C, react for 5~6 h, carry out vacuum distillation, transfer to a reaction kettle, under a nitrogen atmosphere, add dioctyl dithiophosphoric acid in an amount of 0.1~0.14 times the mass of the epoxy polyether silicone oil, heat up to 95~105 °C, react for 6~8 h, carry out vacuum distillation to obtain phosphosilicone oil. S4. Mix calcium carbonate and deionized water in a mass ratio of 1:50~80, stir evenly, add adipic acid in an amount of 2~3 times the mass of the calcium carbonate, heat up to 70~72 °C, react for 50~70 min, filter and wash with deionized water for 3~5 times, then disperse in phosphosilicone oil in an amount of 8~10 times the mass of the calcium carbonate, stir evenly, heat up to 120~140 °C, stir and react at 800~1200 rpm for 60~90 min, cool down to 50~60 °C, filter and crush, and dry at 40~45 °C to obtain modified calcium carbonate. S5. The composite rubber is subjected to stepwise plasticizing in a Banbury mixer, and modified calcium carbonate, vulcanizing agent, plasticizer and stabilizer are added, followed by continuous mixing. The mixing temperature is 90 - 110 °C and the time is 3 - 5 min. The mass ratio of the composite rubber, modified calcium carbonate, vulcanizing agent, plasticizer and stabilizer is 70 - 100:20 - 40:4 - 6:0.5 - 2.5:0.5 - 1.

5. After mixing, it is transferred to an open mill for refining, then pressed into sheets by a calender, cut according to the fender size, and vulcanized at 160 - 170 °C to obtain the rubber fender.

7. The preparation method of a rubber fender according to claim 6, characterized in that, In the above step S1, the preparation method of mercapto polycaprolactone is as follows: ε-caprolactone, stannous trifluoromethanesulfonate, toluene and tetrahydrofuran are mixed according to the mass ratio of 5:0.1 - 0.2:8:2, and reacted at room temperature for 20 - 40 min. Then, mercaptoethanol with a mass 0.06 - 0.09 times that of ε-caprolactone is added, and after mixing evenly, 3 - 5 cycles of liquid nitrogen cooling, vacuum pumping and thawing operations are carried out. Then it is vacuum sealed and reacted for 12 - 14 h. Trichloromethane with the same mass as ε-caprolactone is added, and after stirring evenly, it is precipitated with methanol and filtered by suction. Finally, it is dried under vacuum to obtain mercapto polycaprolactone.

8. A method for preparing a rubber fender according to claim 6, characterized in that, In the above step S2, the preparation method of the isocyanate derivative is as follows: dicyclopentadiene, hexamethylene diisocyanate and tetrahydrofuran are mixed according to the mass ratio of 1:2 - 3:20, and after stirring evenly, the temperature is raised to 90 - 110 °C. Then, dibutyltin dilaurate as a catalyst with a mass 0.02 - 0.04 times that of dicyclopentadiene is added, and the reaction is carried out for 4 - 6 h. Then, it is subjected to vacuum distillation and vacuum dried at 50 - 60 °C to obtain the isocyanate derivative.

9. The preparation method of a rubber fender according to claim 6, characterized in that, In the above step S2, the preparation method of the modified ethylene-propylene-diene monomer rubber is as follows: ethylene-propylene-diene monomer rubber and styrene are mixed, and after stirring evenly, maleic anhydride, initiator dicumyl peroxide and hexamethylphosphoric triamide are added. After mixing evenly, it is melt extruded and pelletized and dried by a twin-screw extruder to obtain the modified ethylene-propylene-diene monomer rubber. The mass ratio of ethylene-propylene-diene monomer rubber, styrene, maleic anhydride, initiator dicumyl peroxide and hexamethylphosphoric triamide is 90 - 100:2 - 3:1 - 3:0.2 - 0.4:0.4 - 0.

8. The extrusion temperature of the twin-screw extruder is 240 - 280 °C, the residence time is 3 - 6 min, the pressure is 12 - 18 MPa, the temperature of the first zone is 140 - 145 °C, the temperature of the second zone is 140 - 150 °C, the temperature of the third zone is 150 - 160 °C, the temperature of the fourth zone is 145 - 155 °C, and the temperature of the die head is 150 - 160 °C.

10. The preparation method of a rubber fender according to claim 6, characterized in that, In the above step S3, the preparation method of epoxy polyether silicone oil is as follows: hydrogen-containing silicone oil, allyl polyether, allyl epoxy polyether and isopropanol are mixed according to the mass ratio of 10:8 - 12:0.5 - 0.6:5, and after stirring evenly, the temperature is raised to 90 - 92 °C. After reacting for 3 - 4 h, a 2% solution of chloroplatinic acid in isopropanol with a mass 0.05 - 0.1 times that of hydrogen-containing silicone oil is added dropwise at a rate of 1 - 3 ml / min. After cooling to 70 - 72 °C, the reaction is continued for 3 - 4 h. Then, it is subjected to vacuum distillation and vacuum dried at 50 - 60 °C to obtain epoxy polyether silicone oil.