Preparation method of high-weather-resistant wear-resistant rubber material for floating conveying pipe

Abstract

The invention discloses a preparation method of a high-weather-resistance and wear-resistance rubber material for a floating conveying pipe, belongs to the technical field of rubber material preparation, and aims to solve the technical problem that the weather resistance and wear resistance of a rubber material in the prior art need to be further improved. Comprising the following steps: mixing and foaming composite polyol and isophorone diisocyanate to obtain modified polyurethane foam; according to the preparation method, the reinforcing agent of which the surface is modified by a perfluoro group is prepared and is used for reinforcing the stability of the modified polyurethane foam, and the modified chain extender taking nano titanium dioxide as a matrix is prepared, so that the structure of the modified toughening agent is enriched, and finally, the foam structure is filled by the modified toughening agent; finally, the modified rubber material with wear resistance, impact resistance, corrosion resistance and weather resistance is prepared.

Description

Technical Field

[0001] This invention relates to the field of rubber material preparation technology, specifically to a method for preparing high weather-resistant and wear-resistant rubber materials for floating transport pipes. Background Technology

[0002] Floating conveyor pipes are core components of water transport systems and are commonly used in dredging, cleanup, marine mining, and other fields. They operate in complex and harsh environments and face challenges such as UV aging, salt spray corrosion, and material erosion. Therefore, high weather resistance and high wear resistance are required for their outer rubber coating materials.

[0003] While traditional styrene-butadiene rubber and natural rubber have good processability, they are prone to aging and cracking under strong ultraviolet radiation and long-term erosion. To improve service life, the industry is gradually adopting ethylene propylene diene monomer (EPDM) rubber, combined with fillers such as nano-alumina and carbon black for structural optimization, which effectively improves its aging resistance and wear resistance. At the same time, the introduction of dynamic vulcanization and nanocomposite processes allows the material to achieve a better balance between flexibility and strength, providing stronger support for the stable operation of floating conveyor pipes under more severe working conditions.

[0004] Existing technology CN119081271B discloses a weather-resistant and anti-aging polyethylene pipe and its preparation method. It uses high-density polyethylene resin, linear low-density polyethylene resin, polyimide resin micropowder, nano-silica, nano-hexagonal boron nitride, polybenzimidazole fiber, oxalic acid, zinc glycyrrhizate, antioxidant 1010, hindered amine light stabilizer, polydimethylsiloxane titanate crosslinked polymer, and 3-methacryloyloxypropyltriethoxysilane as raw materials. Specifically, the polyimide resin micropowder, oxalic acid, and zinc glycyrrhizate are mixed evenly, and then modified at 300℃-350℃ for 30-60 minutes to obtain a modified product. This modified product effectively improves the weather resistance and anti-aging properties of the pipe. The components are well-matched, and the special modification preparation method better leverages the synergistic effect of the components, significantly improving the weather resistance and anti-aging properties of the polyethylene pipe.

[0005] However, the above invention improves the composite properties of materials such as weather resistance by utilizing the synergistic effect of polyimide resin micro powder, oxalic acid and zinc glycyrrhizate. However, this improvement relies more on the functional superposition of the additives themselves. Its mechanism of action is mainly reflected in physical shielding, free radical scavenging and ultraviolet absorption. Although it can indeed improve the stability of materials in complex environments in the short term, its long-term effect is easily affected by problems such as component migration, thermal degradation or uneven distribution.

[0006] In addition, the compatibility between the filler and the polyethylene matrix has always been an issue. Due to the significant difference in polarity, micro-defects are easily formed during processing and service, thereby weakening the consistency and controllability of the overall material properties, which means that the material properties need to be further improved. Summary of the Invention

[0007] The purpose of this invention is to provide a method for preparing a high weather-resistant and wear-resistant rubber material for floating conveying pipes, which solves the technical problem that the weather resistance and wear resistance of rubber materials in the prior art need to be further improved.

[0008] The objective of this invention can be achieved through the following technical solution: a method for preparing a high weather-resistant and wear-resistant rubber material for floating conveying pipes, comprising the following steps:

[0009] S1. Modified polyurethane foam is obtained by mixing and foaming a composite polyol and isophorone diisocyanate.

[0010] S2. The modified polyurethane foam is transferred to a mold, and a modified toughening agent is added to the mold and the foamed polyurethane is immersed in it. The mold is then transferred to a vacuum instrument, vacuum injection molded, and post-processed to obtain the modified rubber material.

[0011] The reaction principle for preparing modified rubber materials is as follows: After the modified toughening agent is completely filled into the modified polyurethane foam through vacuum injection molding, under heating conditions, the epoxy three-membered ring is prone to ring opening due to tension. Unreacted amino or secondary amino groups in the foam structure can act as nucleophiles to attack the epoxy carbon, resulting in a nucleophilic ring-opening reaction and forming a stable β-hydroxyamine structure. This enhances the interfacial strength between the foam and the toughening agent through chemical bonding, closes the cell structure, and thus prepares the modified rubber material.

[0012] Furthermore, in step S2, the vacuum degree of the vacuum instrument is -0.09MPa; the post-processing includes: transferring the material to an oven at a temperature of 80-100℃, keeping it warm and standing for 1-2 hours, repeating the operation until the modified toughening agent completely fills the modified polyurethane foam, and then obtaining the modified rubber material.

[0013] Furthermore, in step S1, the method for preparing modified polyurethane foam includes the following steps:

[0014] A1. Add polyethylene glycol, glycerol, L-580, stannous octoate T-9, reinforcing agent and deionized water to a reaction vessel, and stir at 1600-1800 rpm for 10-15 min at room temperature to obtain a composite polyol.

[0015] A2. Add the composite polyol to the reactor, purge with nitrogen for protection, raise the reactor temperature to 40-60℃, add the calculated amount of isophorone diisocyanate to the reactor, stir at 3200-3600 rpm for 10-15 seconds, transfer the reaction solution to the mold, allow it to mature naturally for 20-24 hours, and then perform post-treatment to obtain modified polyurethane foam.

[0016] The reaction equation for preparing modified polyurethane foam is as follows:

[0017]

[0018] In the formula:

[0019] The reaction principle for preparing modified polyurethane foam is as follows: under the action of a catalyst, isophorone diisocyanate undergoes an addition reaction with the active sites on polyol compounds and reinforcing agents to generate a polyurethane structure. At the same time, the deionized water added to the reaction system reacts with the isocyanate groups to release carbon dioxide gas, thereby initiating the foaming process and forming a modified polyurethane foam with a porous structure.

[0020] Further, in step A1, the ratio of the amount of polydiethanol, glycerol, L-580, stannous octoate T-9, reinforcing agent, and deionized water is 40-60g:5-6g:1-2g:1-2g:4-5g:2-3g; in step A2, the amount of isophorone diisocyanate is 0.8-1.0 times the molar amount of hydroxyl groups in the composite polyol; the post-treatment includes: after curing, washing the foam material 3-5 times with deionized water and anhydrous ethanol, then transferring the foam material to a vacuum drying oven at a temperature of 70-80℃ and vacuum drying to constant weight to obtain modified polyurethane foam.

[0021] Furthermore, the preparation method of the reinforcing agent is as follows: graphene oxide, deionized water and anhydrous ethanol are added to the reaction vessel and stirred. After nitrogen protection is introduced, the pH of the reaction system is adjusted to 4-5 with acetic acid. Then, the temperature of the reaction vessel is raised to 40-50℃ and perfluorooctyltrimethoxysilane is added to the reaction vessel. The mixture is kept at this temperature and stirred for 1-2 hours. The reinforcing agent is then obtained after post-treatment.

[0022] The reaction principle for preparing the reinforcing agent is as follows: Under acidic conditions, the methoxysilane in perfluorooctyltrimethoxysilane hydrolyzes to produce silanol groups, which then react with active functional groups such as hydroxyl, epoxy, and carboxyl groups on graphene oxide, thereby grafting perfluorinated groups onto the surface of graphene oxide to prepare the reinforcing agent.

[0023] Furthermore, the ratio of graphene oxide, deionized water, anhydrous ethanol, and perfluorooctyltrimethoxysilane is as follows. The post-treatment includes: after the reaction is completed, wait for the temperature of the reaction vessel to drop to room temperature, filter the reaction solution to collect the filter cake, wash the filter cake 3-5 times with deionized water and anhydrous ethanol, transfer the filter cake to a vacuum drying oven, and vacuum dry it at 60-80℃ to constant weight to obtain the reinforcing agent.

[0024] Furthermore, the preparation method of the modified toughening agent includes the following steps:

[0025] B1. 2,4,6-trivinyl-2,4,6-trimethylcyclotrisiloxane, trifluoropropylmethylcyclotrisiloxane and N,N-dimethylformamide are added to a reaction vessel. After the temperature of the reaction vessel is raised to 100-120℃, sodium hydroxide is added to the reaction vessel. After the reaction is kept at this temperature for 4-5 hours, a modified chain extender is added to the reaction vessel. The reaction is kept at this temperature for 2-3 hours. The post-treatment yields telomerized silicone oil.

[0026] B2. Add telomerized silicone oil and N,N-dimethylformamide to the reactor, purge with nitrogen for protection, and then reduce the reactor temperature to 10-15℃. Add an oxidant to the reactor and keep it at the temperature for 1-2 hours. The modified toughening agent is then obtained through post-treatment.

[0027] The reaction equation for preparing the modified toughening agent is as follows:

[0028]

[0029] In the formula: This indicates a modified chain extender.

[0030] The reaction principle for preparing the modified toughening agent is as follows: Under alkaline catalysis, 2,4,6-trivinyl-2,4,6-trimethylcyclotrisiloxane and trifluoropropylmethylcyclotrisiloxane are converted into telomerized silicone oil containing vinyl side chains through ring-opening polymerization. Multiple active sites are generated by hydrolysis of the siloxy groups on the modified chain extender, thereby achieving chain growth and hybridization, thus preparing the telomerized silicone oil. Under low temperature and inert atmosphere, benzoic acid peroxide is used to selectively oxidize the vinyl groups on the polysiloxane chain to epoxy groups, thereby preparing the modified toughening agent.

[0031] Further, in step B1, the ratio of 2,4,6-trivinyl-2,4,6-trimethylcyclotrisiloxane, trifluoropropylmethylcyclotrisiloxane, N,N-dimethylformamide, sodium hydroxide, and modified chain extender is 4-5g:6-8g:50-54mL:0.3-0.5g:2-3g. The post-treatment includes: after the reaction is completed, wait for the temperature of the reaction vessel to drop to room temperature, adjust the reaction system to neutral using 1M dilute hydrochloric acid aqueous solution, allow the organic layer to stand and separate, wash the organic layer with deionized water 3-5 times, dry the organic phase with anhydrous sodium sulfate, filter and collect the filtrate, transfer the filtrate to a rotary evaporator at a temperature of 80-100℃, and distill under reduced pressure until no liquid is collected to obtain telomerized silicone oil;

[0032] Further, in step B2, the ratio of the polymerized silicone oil, N,N-dimethylformamide, and oxidant is 6-8g:20-24mL:1-2g, wherein the oxidant is benzoic acid peroxide. The post-treatment includes: after the reaction is completed, wait for the temperature of the reaction vessel to drop to room temperature, add sodium bicarbonate to the reaction vessel until no bubbles are generated, extract the reaction solution with dichloromethane 3-5 times to obtain an organic layer, wash the organic layer with deionized water 3-5 times, dry the organic phase with anhydrous sodium sulfate, filter and collect the filtrate, transfer the filtrate to a rotary evaporator at a temperature of 80-100℃, and distill under reduced pressure until no liquid is collected to obtain the modified toughening agent.

[0033] Furthermore, the modified chain extender is prepared by adding nano-titanium dioxide, anhydrous ethanol and triethylamine into a reaction vessel and stirring. After purging with nitrogen, the temperature of the reaction vessel is raised to 40-60℃, and 3-(2,3-epoxypropoxy)propyltrimethoxysilane is added to the reaction vessel. The mixture is kept at this temperature and stirred for 40-60 minutes. The modified chain extender is then obtained through post-treatment.

[0034] The structural diagram of the modified chain extender is as follows:

[0035] The reaction principle for preparing the modified chain extender is as follows: under the promotion of triethylamine and heating, the epoxy group on 3-(2,3-epoxypropoxy)propyltrimethoxysilane undergoes ring opening, and the resulting active free radicals react with the silanol groups on nano-titanium dioxide, thereby crosslinking the silanol structure on the modified nano-titanium dioxide, and finally preparing the modified chain extender.

[0036] Furthermore, the ratio of nano-titanium dioxide, anhydrous ethanol, triethylamine, and 3-(2,3-epoxypropoxy)propyltrimethoxysilane is 5-6g:40-50mL:0.3-0.5g:1-2g. The post-treatment includes: after the reaction is completed, wait for the temperature of the reaction vessel to drop to room temperature, filter the reaction solution to collect the filter cake, wash the filter cake 3-5 times with deionized water and anhydrous ethanol, transfer the filter cake to a vacuum drying oven, and vacuum dry it at 60-80℃ to constant weight to obtain the modified chain extender.

[0037] The present invention has the following beneficial effects:

[0038] 1. This invention modifies graphene oxide with perfluoroalkyltrimethoxysilane, forming stable covalent bonds with a polyurethane matrix. Its layered structure provides rigid support at the microscopic level, effectively inhibiting the propagation of microcracks during wear. The modified chain extender is uniformly dispersed and enhances interfacial adhesion through an epoxy silane coupling agent. Its nano-skeleton structure and foam network synergistically construct a microscale reinforced support network, improving the overall deformation resistance of the material. Simultaneously, the introduction of polymerized silicone oil and chain extender forms flexible organosilicon segments that can undergo reversible deformation under impact loads, absorbing impact energy and delaying crack propagation. After the foam structure is fully filled, a reinforcing network with a supporting function is formed, which not only retains the buffering and shock absorption functions but also works together with the modified toughening agent to form a strong and tough composite material. The distribution of the foam allows energy to be effectively absorbed and dispersed when external forces are applied, reducing the direct impact of impacts on the material and improving impact resistance. Finally, a wear-resistant and impact-resistant composite rubber material is obtained.

[0039] 2. This invention utilizes graphene oxide as a two-dimensional layered material. Its high specific surface area and excellent chemical stability endow it with outstanding barrier function. Furthermore, the perfluorinated groups modified on its surface possess extremely low surface energy and excellent hydrophobic and oleophobic properties, which can significantly reduce the affinity of the material surface for polar or corrosive media, thereby effectively blocking the penetration of water molecules, oxygen, and corrosive ions and delaying the diffusion of corrosive media into the interior. Secondly, the foam structure is fully filled through vacuum injection molding to form a continuous and dense three-dimensional network, which significantly extends the corrosion path and improves the overall barrier performance. At the same time, the cross-linked network structure formed by the modified chain extender and polysiloxane in the system further seals the micro-channels, enhances the overall density and chemical inertness of the material, and thus effectively inhibits the structural deterioration and performance loss of the material in corrosive environments. Through the organic combination of barrier effect, path delay effect, and cross-linking sealing effect, the corrosion resistance of the material is significantly improved.

[0040] 3. The modified toughening agent prepared in this invention fully penetrates and fills the interior of the polyurethane foam structure during vacuum injection molding. Its highly reactive epoxy structure undergoes a nucleophilic ring-opening reaction with the residual amino groups in the foam to form stable β-hydroxyamine chemical bonds, thereby constructing a dense and stable interface structure. At the same time, the modified nano-titanium dioxide introduced into the toughening agent is uniformly dispersed in the foam pores, forming a three-dimensional UV-resistant nano-network. This network can not only directly absorb and scatter ultraviolet light and slow down the degradation of the main chain, but also has a certain free radical capture ability, effectively interrupting the UV-induced aging chain reaction. Furthermore, the covalent connection between the perfluoroalkyl modified graphene oxide and the polyurethane enhances the interface stability. Its low surface energy characteristics help to construct a hydrophobic self-cleaning layer, thereby reducing the participation of water and oxygen required for photo-oxidation reactions. Under the structural closure and functional synergy among the multiple components, the material as a whole exhibits excellent UV stability and long-term weather resistance. Detailed Implementation

[0041] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] The L-580 used in this invention was purchased from Shanghai Kaiyin Chemical Co., Ltd., and its brand name is Momentive silicone oil L-580 (USA); stannous octoate was purchased from Guangdong Wengjiang Chemical Reagent Co., Ltd., and its product number is T-9PA42718; polyethylene glycol was purchased from Guangdong Wengjiang Chemical Reagent Co., Ltd., and its product number is DC00328; graphene oxide was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., and its product number is G405797; nano silica was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., and its product number is S104597.

[0043] Example 1

[0044] This embodiment provides a method for preparing modified polyurethane foam for use in the fabrication of highly weather-resistant and wear-resistant rubber materials for floating transport pipes, including the following steps:

[0045] Step ①: Preparation of reinforcing agent

[0046] Weigh out 40.0 g of graphene oxide, 100.0 mL of deionized water, and 100.0 mL of anhydrous ethanol and add them to a reaction vessel. Stir the mixture and purge it with nitrogen. Adjust the pH of the reaction system to 5 with acetic acid. Then, raise the temperature of the reaction vessel to 40°C and add 10.0 g of perfluorooctyltrimethoxysilane. Keep the mixture warm and stir for 1 hour. After the reaction is complete, let the temperature of the reaction vessel drop to room temperature. Filter the reaction solution and collect the filter cake. Wash the filter cake three times with deionized water and anhydrous ethanol. Transfer the filter cake to a vacuum drying oven and vacuum dry it at 60°C to constant weight to obtain the reinforcing agent.

[0047] Step ②: Preparation of composite polyols

[0048] Weigh out 400.0g of polyethylene glycol, 50.0g of glycerol, 10.0g of L-580, 10.0g of stannous octoate T-9, 40.0g of reinforcing agent and 20.0g of deionized water and add them to the reaction vessel. Stir at 1600rpm for 10min at room temperature to obtain the composite polyol.

[0049] Step 3: Preparation of modified polyurethane foam

[0050] Weigh 400.0g of the composite polyol and add it to the reaction vessel. After purging with nitrogen, raise the temperature of the reaction vessel to 40℃. Add isophorone diisocyanate at 0.8 times the molar amount of hydroxyl groups in the composite polyol to the reaction vessel. Stir at 3200rpm for 10s. Transfer the reaction solution to a mold and allow it to mature naturally for 20h. After maturation, wash the foam material three times with deionized water and anhydrous ethanol. Transfer the foam material to a vacuum drying oven at 70℃ and vacuum dry it to constant weight to obtain modified polyurethane foam.

[0051] Example 2

[0052] This embodiment provides a method for preparing modified polyurethane foam for use in the fabrication of highly weather-resistant and wear-resistant rubber materials for floating transport pipes, including the following steps:

[0053] Step ①: Preparation of reinforcing agent

[0054] Weigh out 50.0 g of graphene oxide, 120.0 mL of deionized water, and 120.0 mL of anhydrous ethanol and add them to a reaction vessel. Stir the mixture and purge it with nitrogen. Adjust the pH of the reaction system to 4 with acetic acid. Then, raise the temperature of the reaction vessel to 50°C and add 20.0 g of perfluorooctyltrimethoxysilane. Keep the mixture warm and stir for 2 hours. After the reaction is complete, let the temperature of the reaction vessel drop to room temperature. Filter the reaction solution and collect the filter cake. Wash the filter cake 5 times with deionized water and anhydrous ethanol. Transfer the filter cake to a vacuum drying oven and vacuum dry it at 80°C to constant weight to obtain the reinforcing agent.

[0055] Step ②: Preparation of composite polyols

[0056] Weigh out 600.0g of polyethylene glycol, 60.0g of glycerol, 20.0g of L-580, 20.0g of stannous octoate T-9, 50.0g of reinforcing agent and 30.0g of deionized water and add them to the reaction vessel. Stir at 1800rpm for 15min at room temperature to obtain the composite polyol.

[0057] Step 3: Preparation of modified polyurethane foam

[0058] Weigh 400.0g of the composite polyol and add it to the reaction vessel. After purging with nitrogen, raise the temperature of the reaction vessel to 60℃. Add isophorone diisocyanate at 1.0 times the molar amount of hydroxyl groups in the composite polyol to the reaction vessel. Stir at 3600rpm for 15s. Transfer the reaction solution to a mold and allow it to mature naturally for 24h. After maturation, wash the foam material 5 times with deionized water and anhydrous ethanol. Transfer the foam material to a vacuum drying oven at 80℃ and vacuum dry it to constant weight to obtain modified polyurethane foam.

[0059] Example 3

[0060] This embodiment provides a method for preparing modified polyurethane foam for use in the fabrication of highly weather-resistant and wear-resistant rubber materials for floating transport pipes, including the following steps:

[0061] Step ①: Preparation of reinforcing agent

[0062] Weigh out 45.0 g of graphene oxide, 120.0 mL of deionized water, and 120.0 mL of anhydrous ethanol and add them to a reaction vessel. Stir the mixture and purge it with nitrogen. Adjust the pH of the reaction system to 4 with acetic acid. Then, raise the temperature of the reaction vessel to 45°C and add 16.0 g of perfluorooctyltrimethoxysilane. Keep the mixture warm and stir for 2 hours. After the reaction is complete, let the temperature of the reaction vessel drop to room temperature. Filter the reaction solution and collect the filter cake. Wash the filter cake four times with deionized water and anhydrous ethanol. Transfer the filter cake to a vacuum drying oven and vacuum dry it at 70°C to constant weight to obtain the reinforcing agent.

[0063] Step 2: Preparation of composite polyols

[0064] Weigh out 500.0g of polyethylene glycol, 54.0g of glycerol, 16.0g of L-580, 16.0g of stannous octoate T-9, 45.0g of reinforcing agent and 25.0g of deionized water and add them to the reaction vessel. Stir at 1700rpm for 12min at room temperature to obtain the composite polyol.

[0065] Step 3: Preparation of modified polyurethane foam

[0066] Weigh 400.0g of the composite polyol and add it to the reaction vessel. After purging with nitrogen, raise the temperature of the reaction vessel to 50℃. Add isophorone diisocyanate at 0.9 times the molar amount of hydroxyl groups in the composite polyol to the reaction vessel. Stir at 3600rpm for 12s. Transfer the reaction solution to a mold and allow it to mature naturally for 21h. After maturation, wash the foam material four times with deionized water and anhydrous ethanol. Transfer the foam material to a vacuum drying oven at 75℃ and vacuum dry it to constant weight to obtain modified polyurethane foam.

[0067] Example 4

[0068] This embodiment provides a method for preparing a modified toughening agent for the preparation of a high-weather-resistant and wear-resistant rubber material for floating conveying pipes, including the following steps:

[0069] Step I: Preparation of modified chain extender

[0070] Weigh out 50.0g of nano titanium dioxide, 400.0mL of anhydrous ethanol and 3.0g of triethylamine and add them to the reaction vessel. Stir and purge with nitrogen to raise the temperature of the reaction vessel to 40℃. Add 10.0g of 3-(2,3-epoxypropoxy)propyltrimethoxysilane to the reaction vessel and keep it heated and stirred for 40min. After the reaction is complete, wait for the temperature of the reaction vessel to drop to room temperature, filter the reaction solution and collect the filter cake. Wash the filter cake three times with deionized water and anhydrous ethanol. Transfer the filter cake to a vacuum drying oven and vacuum dry it at 60℃ to constant weight to obtain the modified chain extender.

[0071] Step II: Preparation of telomerized silicone oil

[0072] Weigh out 40.0g of 2,4,6-trivinyl-2,4,6-trimethylcyclotrisiloxane, 60.0g of trifluoropropylmethylcyclotrisiloxane, and 500.0mL of N,N-dimethylformamide and add them to a reaction vessel. After the temperature of the reaction vessel is raised to 100℃, add 3.0g of sodium hydroxide and keep the reaction at this temperature for 4 hours. Then add 20.0g of modified chain extender and keep the reaction at this temperature for 2 hours. After the reaction is completed, wait for the temperature of the reaction vessel to drop to room temperature. Adjust the reaction system to neutral using 1M dilute hydrochloric acid aqueous solution, allow it to stand and separate the organic layer. Wash the organic layer three times with deionized water, dry the organic phase with anhydrous sodium sulfate, and then filter to collect the filtrate. Transfer the filtrate to a rotary evaporator at 80℃ and distill it under reduced pressure until no liquid is collected, thus obtaining the polymerized silicone oil.

[0073] Step III: Preparation of Modified Toughening Agent

[0074] Weigh out 60.0g of telomerized silicone oil and 200.0mL of N,N-dimethylformamide and add them to the reactor. After purging with nitrogen for protection, lower the reactor temperature to 15℃ and add 10.0g of benzoic acid peroxide. Keep the reactor at this temperature for 1 hour. After the reaction is complete, wait for the reactor temperature to drop to room temperature and add sodium bicarbonate until no more bubbles are generated. Extract the reaction solution three times with dichloromethane to obtain the organic layer. Wash the organic layer three times with deionized water and dry the organic phase with anhydrous sodium sulfate. Filter and collect the filtrate. Transfer the filtrate to a rotary evaporator at 80℃ and distill under reduced pressure until no liquid is collected, thus obtaining the modified toughening agent.

[0075] Example 5

[0076] This embodiment provides a method for preparing a modified toughening agent for the preparation of a high-weather-resistant and wear-resistant rubber material for floating conveying pipes, including the following steps:

[0077] Step I: Preparation of modified chain extender

[0078] Weigh out 60.0g of nano titanium dioxide, 500.0mL of anhydrous ethanol and 5.0g of triethylamine and add them to the reaction vessel. Stir and purge with nitrogen to raise the temperature of the reaction vessel to 60℃. Add 20.0g of 3-(2,3-epoxypropoxy)propyltrimethoxysilane to the reaction vessel and keep it heated and stirred for 60min. After the reaction is completed, wait for the temperature of the reaction vessel to drop to room temperature, filter the reaction solution and collect the filter cake. Wash the filter cake 5 times with deionized water and anhydrous ethanol, and then transfer the filter cake to a vacuum drying oven and vacuum dry it at 70℃ to constant weight to obtain the modified chain extender.

[0079] Step II: Preparation of telomerized silicone oil

[0080] Weigh out 50.0g of 2,4,6-trivinyl-2,4,6-trimethylcyclotrisiloxane, 80.0g of trifluoropropylmethylcyclotrisiloxane, and 540.0mL of N,N-dimethylformamide and add them to a reaction vessel. After the temperature of the reaction vessel is raised to 120℃, add 5.0g of sodium hydroxide and keep the reaction at this temperature for 5 hours. Then add 30.0g of modified chain extender and keep the reaction at this temperature for 2-3 hours. After the reaction is complete, wait for the temperature of the reaction vessel to drop to room temperature. Adjust the reaction system to neutral using 1M dilute hydrochloric acid aqueous solution, allow it to stand and separate the organic layer. Wash the organic layer 5 times with deionized water, dry the organic phase with anhydrous sodium sulfate, and then filter to collect the filtrate. Transfer the filtrate to a rotary evaporator at 100℃ and distill it under reduced pressure until no liquid is collected, thus obtaining the polymerized silicone oil.

[0081] Step III: Preparation of Modified Toughening Agent

[0082] Weigh out 80.0g of telomerized silicone oil and 240.0mL of N,N-dimethylformamide and add them to the reactor. After purging with nitrogen for protection, the reactor temperature is lowered to 10℃. Then, add 20.0g of benzoic acid peroxide to the reactor and keep it at this temperature for 2 hours. After the reaction is complete, wait for the reactor temperature to drop to room temperature and add sodium bicarbonate to the reactor until no more bubbles are generated. Then, extract the reaction solution with dichloromethane five times to obtain an organic layer. Wash the organic layer five times with deionized water and dry the organic phase with anhydrous sodium sulfate. Filter and collect the filtrate. Transfer the filtrate to a rotary evaporator at 100℃ and distill it under reduced pressure until no liquid is collected, thus obtaining the modified toughening agent.

[0083] Example 6

[0084] This embodiment provides a method for preparing a modified toughening agent for the preparation of a high-weather-resistant and wear-resistant rubber material for floating conveying pipes, including the following steps:

[0085] Step I: Preparation of modified chain extender

[0086] Weigh out 54.0g of nano-titanium dioxide, 450.0mL of anhydrous ethanol and 4.0g of triethylamine and add them to the reaction vessel. Stir the mixture and then raise the temperature of the reaction vessel to 50℃ after purging with nitrogen. Add 16.0g of 3-(2,3-epoxypropoxy)propyltrimethoxysilane to the reaction vessel and keep it heated and stirred for 50min. After the reaction is complete, wait for the temperature of the reaction vessel to drop to room temperature, filter the reaction solution and collect the filter cake. Wash the filter cake four times with deionized water and anhydrous ethanol, and then transfer the filter cake to a vacuum drying oven and vacuum dry it at 70℃ to constant weight to obtain the modified chain extender.

[0087] Step II: Preparation of telomerized silicone oil

[0088] Weigh out 45.0g of 2,4,6-trivinyl-2,4,6-trimethylcyclotrisiloxane, 70.0g of trifluoropropylmethylcyclotrisiloxane, and 540.0mL of N,N-dimethylformamide and add them to a reaction vessel. After the temperature of the reaction vessel is raised to 120℃, add 4.0g of sodium hydroxide and keep the reaction at this temperature for 5h. Then add 25.0g of modified chain extender and keep the reaction at this temperature for 3h. After the reaction is completed, wait for the temperature of the reaction vessel to drop to room temperature. Adjust the reaction system to neutral using 1M dilute hydrochloric acid aqueous solution, and then let it stand to separate the organic layer. Wash the organic layer with deionized water 4 times, dry the organic phase with anhydrous sodium sulfate, and then filter to collect the filtrate. Transfer the filtrate to a rotary evaporator at a temperature of 90℃ and distill it under reduced pressure until no liquid is collected, thus obtaining the polymerized silicone oil.

[0089] Step III: Preparation of Modified Toughening Agent

[0090] Weigh out 70.0g of telomerized silicone oil and 210.0mL of N,N-dimethylformamide and add them to the reactor. After purging with nitrogen for protection, lower the reactor temperature to 12℃ and add 16.0g of benzoic acid peroxide. Keep the reactor at this temperature for 2 hours. After the reaction is complete, wait for the reactor temperature to drop to room temperature and add sodium bicarbonate until no more bubbles are generated. Extract the reaction solution with dichloromethane four times to obtain an organic layer. Wash the organic layer with deionized water four times and dry the organic phase with anhydrous sodium sulfate. Filter and collect the filtrate. Transfer the filtrate to a rotary evaporator at 90℃ and distill under reduced pressure until no liquid is collected, thus obtaining the modified toughening agent.

[0091] Example 7

[0092] This embodiment provides a method for preparing a modified toughening agent for the preparation of a high-weather-resistant and wear-resistant rubber material for floating conveying pipes, including the following steps:

[0093] The modified polyurethane foam prepared in Example 1 was transferred into a mold, and the modified toughening agent prepared in Example 4 was added to the mold and the foamed polyurethane was immersed in it. The mold was then transferred to a vacuum instrument, and the vacuum degree of the vacuum instrument was set to -0.09 MPa. After vacuum injection molding, the material was transferred to an oven at a temperature of 80°C and kept at that temperature for 1 hour. The operation was repeated until the modified toughening agent completely filled the modified polyurethane foam, and the modified rubber material was obtained.

[0094] Example 8

[0095] This embodiment provides a method for preparing a modified toughening agent for the preparation of a high-weather-resistant and wear-resistant rubber material for floating conveying pipes, including the following steps:

[0096] The modified polyurethane foam prepared in Example 2 was transferred into a mold, and the modified toughening agent prepared in Example 5 was added to the mold and the foamed polyurethane was immersed in it. The mold was then transferred to a vacuum instrument, and the vacuum degree of the vacuum instrument was set to -0.09 MPa. After vacuum injection molding, the material was transferred to an oven at 100°C and kept at that temperature for 2 hours. The operation was repeated until the modified toughening agent completely filled the modified polyurethane foam, and the modified rubber material was obtained.

[0097] Example 9

[0098] This embodiment provides a method for preparing a modified toughening agent for the preparation of a high-weather-resistant and wear-resistant rubber material for floating conveying pipes, including the following steps:

[0099] The modified polyurethane foam prepared in Example 3 was transferred into a mold, and the modified toughening agent prepared in Example 6 was added to the mold and the foamed polyurethane was immersed in it. The mold was then transferred to a vacuum instrument, and the vacuum degree of the vacuum instrument was set to -0.09 MPa. After vacuum injection molding, the material was transferred to an oven at a temperature of 90°C and kept at that temperature for 2 hours. The operation was repeated until the modified toughening agent completely filled the modified polyurethane foam, and the modified rubber material was obtained.

[0100] Comparative Example 1

[0101] The difference between this comparative example and Example 9 is that, in the preparation process of the modified polyurethane foam used, step ① is omitted, and in step ②, graphene oxide is used to replace the reinforcing agent in an equal amount.

[0102] Comparative Example 2

[0103] The difference between this comparative example and Example 9 is that the modified polyurethane foam used in this example omits the use of a reinforcing agent in step ② of the preparation process.

[0104] Comparative Example 3

[0105] The difference between this comparative example and Example 9 is that the modified toughening agent used in step II of the preparation process omits the use of the modified chain extender.

[0106] Performance testing:

[0107] The impact resistance of the modified rubber materials prepared in Examples 7-9 and Comparative Examples 1-3 was tested in accordance with the standard GB / T 1843-2008 "Determination of Impact Strength of Plastic Cantilever Beams".

[0108] The volumetric abrasion of the modified rubber materials prepared in Examples 7-9 and Comparative Examples 1-3 was tested in accordance with the standard GB / T 9867-2008 "Determination of abrasion resistance of vulcanized rubber or thermoplastic rubber (rotary roller abrasion mill method)".

[0109] The corrosion resistance of the modified rubber materials prepared in Examples 7-9 and Comparative Examples 1-3 was tested in accordance with the standard HG / T 4087-2009 "Plastic Alloy Corrosion-Resistant Composite Pipes".

[0110] The modified rubber materials prepared in Examples 7-9 and Comparative Examples 1-3 were subjected to ultraviolet irradiation treatment according to standard GB / T 16422.3-2022 "Laboratory Light Source Exposure Test Methods for Plastics - Part 3: Fluorescent Ultraviolet Lamps". The performance change rate of the modified rubber materials was determined according to standards GB / T 1843-2008 and GB / T 9867-2008. The specific data are shown in Table 1.

[0111] Table 1 - Performance Test Data for Each Sample

[0112]

[0113] Data Analysis:

[0114] A comparative analysis of the data in Table 1 reveals that the impact strength of the cantilever beam prepared by this invention is 70.1 kJ·m. -2 The volumetric wear amount is 11mm. 3 The corrosion rate of 30% H2SO4 is 0.9 g·m. -2 The corrosion rate of 40% NaOH is 1.1 g·m -2 Meanwhile, after UV aging, the cantilever beam retained 99.4% of its impact strength and 100.7% of its volumetric wear, with all data being superior to the comparative example.

[0115] Comparative analysis of the data in Table 1 revealed that although Comparative Example 1 retained graphene oxide as a reinforcing agent, its interfacial affinity in the polyurethane matrix was significantly reduced due to the lack of perfluoroalkyl modification. The unmodified graphene oxide surface is rich in polar functional groups such as carboxyl and hydroxyl groups, which are prone to aggregation and difficult to disperse uniformly in the microporous structure of the foam. Consequently, graphene cannot effectively transfer load at the interface, and stress concentration exists between the reinforcing phase and the matrix. Secondly, during impact, the impact load is not dispersed and absorbed in time, making the material more prone to fracture. At the same time, the lack of hydrophobic protection from perfluoro groups also reduces the surface stability of the material, making it easier for corrosive media to penetrate into the foam structure and cause chemical degradation, thus significantly weakening the corrosion resistance. In addition, although graphene oxide has a certain UV shielding ability, its shielding effect is unstable and prone to failure due to aggregation without dispersants and modifying groups, which in turn significantly reduces the weather resistance of the material.

[0116] Completely eliminating the use of reinforcing agents in Comparative Example 2 means that the foam structure lacks any nano-reinforcing filler materials, which significantly weakens the overall mechanical support of the material. This leads to easy wear and peeling of the material surface during frictional contact. Due to the lack of high-modulus filler support, the foam matrix softens and its load-bearing capacity decreases. Secondly, due to the lack of reinforcing phase to share stress, the material is prone to deformation accumulation when subjected to instantaneous impact loads, which can easily lead to crack initiation and propagation. At the same time, since no spatial barrier is formed inside the material to block the medium, corrosive media can spread rapidly in the micropores, causing accelerated chemical degradation inside the structure. Furthermore, the lack of hydrophobic functional groups or ultraviolet absorbing components on the material surface means that UV radiation directly acts on the polymer backbone, accelerating the aging reaction and causing the material's weather resistance to deteriorate rapidly.

[0117] In Comparative Example 3, the use of modified chain extender was eliminated, stripping the original dual functions of nano-reinforcement and chain extension in the system. This significantly and adversely affected the structural stability and service performance of the material. First, the lack of a chain extension reaction pathway directly leads to a shortening of the polymer backbone and a narrowing of the molecular weight distribution, resulting in an overall decrease in the mechanical properties of the rubber material. This manifests as a significant reduction in compression modulus and resilience, and a significant weakening of the structure's ability to resist loads. Second, the absence of nano-titanium dioxide as an inorganic reinforcing phase results in a lack of effective stress transfer and dispersion mechanisms within the system. Under the action of periodic friction or instantaneous impact loads, stress concentration is likely to occur within the material, inducing the initiation and propagation of cracks. Furthermore, due to the lack of a uniform reinforcing phase distribution in the cell structure, the ability of the micropores to effectively block corrosive media is weakened, allowing liquid or gaseous media to propagate rapidly within the cell channels, thereby accelerating the internal chemical degradation process.

[0118] Ultimately, it is demonstrated that graphene oxide modified with perfluoroalkyl groups not only enhances its interfacial affinity with the polyurethane matrix and significantly improves its uniform dispersion in the cell structure, but also endows the material with excellent hydrophobicity and shielding properties. While improving mechanical properties, it effectively blocks the diffusion of corrosive media, enhancing the material's corrosion resistance and environmental stability. On the other hand, the introduction of nano-titanium dioxide not only plays an inorganic reinforcing role, but its surface activity can also form stable interfacial bonds with the matrix, further promoting stress transmission and structural stability, and improving impact resistance and wear resistance. In addition, the modified chain extender, based on the control of the polyurethane molecular weight distribution, optimizes the cell structure, enhances the continuity and density of the matrix, and provides solid support for the overall performance. The three elements form a synergistic effect at multiple levels, including structural construction, interfacial control, and performance enhancement, thereby achieving a balanced and significant improvement in multiple dimensions of performance, such as mechanical properties, corrosion resistance, wear resistance, and weather resistance.

[0119] The above description is merely an example and illustration of the structure of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the structure of the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A method for preparing a high weather-resistant and wear-resistant rubber material for floating conveying pipes, characterized in that, Includes the following steps: S1. Modified polyurethane foam is obtained by mixing and foaming a composite polyol and isophorone diisocyanate. S2. The modified polyurethane foam is transferred to a mold, and a modified toughening agent is added to the mold and the foamed polyurethane is immersed in it. The mold is then transferred to a vacuum instrument, vacuum injection molded, and post-processed to obtain the modified rubber material.

2. The method for preparing the high weather-resistant and wear-resistant rubber material for floating conveying pipes according to claim 1, characterized in that, In step S1, the method for preparing the modified polyurethane foam includes the following steps: A1. Add polyethylene glycol, glycerol, L-580, stannous octoate T-9, reinforcing agent and deionized water to a reaction vessel, and stir at 1600-1800 rpm for 10-15 min at room temperature to obtain a composite polyol. A2. Add the composite polyol to the reactor, purge with nitrogen for protection, raise the reactor temperature to 40-60℃, add the calculated amount of isophorone diisocyanate to the reactor, stir at 3200-3600 rpm for 10-15 seconds, transfer the reaction solution to the mold, allow it to mature naturally for 20-24 hours, and then perform post-treatment to obtain modified polyurethane foam.

3. The method for preparing the high weather-resistant and wear-resistant rubber material for floating conveying pipes according to claim 2, characterized in that, In step A1, the ratio of the amounts of polyethylene glycol, glycerol, L-580, stannous octoate T-9, reinforcing agent, and deionized water is 40-60g:5-6g:1-2g:1-2g:4-5g:2-3g; in step A2, the amount of isophorone diisocyanate is 0.8-1.0 times the molar amount of hydroxyl groups in the composite polyol.

4. The method for preparing the high weather-resistant and wear-resistant rubber material for floating conveying pipes according to claim 1, characterized in that, The preparation method of the reinforcing agent is as follows: graphene oxide, deionized water and anhydrous ethanol are added to the reaction vessel and stirred. After nitrogen protection, the pH of the reaction system is adjusted to 4-5 with acetic acid. Then, the temperature of the reaction vessel is raised to 40-50℃ and perfluorooctyltrimethoxysilane is added to the reaction vessel. The mixture is kept at this temperature and stirred for 1-2 hours. The reinforcing agent is then obtained after post-treatment.

5. The method for preparing the high weather-resistant and wear-resistant rubber material for floating conveying pipes according to claim 4, characterized in that, The ratio of graphene oxide, deionized water, anhydrous ethanol, and perfluorooctyltrimethoxysilane is 4-5g:10-12mL:10-12mL:1-2g.

6. The method for preparing the high weather-resistant and wear-resistant rubber material for floating conveying pipes according to claim 1, characterized in that, The preparation method of the modified toughening agent includes the following steps: B1. 2,4,6-trivinyl-2,4,6-trimethylcyclotrisiloxane, trifluoropropylmethylcyclotrisiloxane and N,N-dimethylformamide are added to a reaction vessel. After the temperature of the reaction vessel is raised to 100-120℃, sodium hydroxide is added to the reaction vessel. After the reaction is kept at this temperature for 4-5 hours, a modified chain extender is added to the reaction vessel. The reaction is kept at this temperature for 2-3 hours. The post-treatment yields telomerized silicone oil. B2. Add telomerized silicone oil and N,N-dimethylformamide to the reactor, purge with nitrogen for protection, and then reduce the reactor temperature to 10-15℃. Add an oxidant to the reactor and keep it at the temperature for 1-2 hours. The modified toughening agent is then obtained through post-treatment.

7. The method for preparing the high weather-resistant and wear-resistant rubber material for floating conveying pipes according to claim 6, characterized in that, In step B1, the ratio of 2,4,6-trivinyl-2,4,6-trimethylcyclotrisiloxane, trifluoropropylmethylcyclotrisiloxane, N,N-dimethylformamide, sodium hydroxide, and modified chain extender is 4-5g:6-8g:50-54mL:0.3-0.5g:2-3g; in step B2, the ratio of telomerized silicone oil, N,N-dimethylformamide, and oxidant is 6-8g:20-24mL:1-2g, wherein the oxidant is benzoic acid peroxide.

8. The method for preparing the high weather-resistant and wear-resistant rubber material for floating conveying pipes according to claim 6, characterized in that, The modified chain extender is prepared by adding nano-titanium dioxide, anhydrous ethanol and triethylamine into a reaction vessel and stirring. After purging with nitrogen, the temperature of the reaction vessel is raised to 40-60℃, and 3-(2,3-epoxypropoxy)propyltrimethoxysilane is added to the reaction vessel. The mixture is kept at this temperature and stirred for 40-60 minutes. The modified chain extender is then obtained through post-treatment.

9. The method for preparing the high weather-resistant and wear-resistant rubber material for floating conveying pipes according to claim 8, characterized in that, The ratio of nano-titanium dioxide, anhydrous ethanol, triethylamine, and 3-(2,3-epoxypropoxy)propyltrimethoxysilane is 5-6g:40-50mL:0.3-0.5g:1-2g.

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