A composite plasticizer for high and low temperature resistant cables and its preparation method

Abstract

This invention discloses a composite plasticizer for high and low temperature resistant cables and its preparation method, belonging to the technical field of cable plasticizers. It addresses the technical problem that the high and low temperature resistance and UV resistance of existing composite plasticizers for cables need further improvement. The invention includes the following steps: mixing 30-50 parts by weight of a main plasticizer, 20-40 parts by weight of an auxiliary plasticizer, 20-40 parts by weight of an excipient, and 60-70 parts by weight of a solvent to obtain a composite plasticizer. The main plasticizer is obtained by preparing a citric acid copolymer and modified chloroprene rubber and crosslinking them. An auxiliary plasticizer is prepared by reacting epoxidized soybean oil with a functional crosslinking agent. The mixture is then further mixed with the excipient and solvent to obtain a composite plasticizer that enhances the wear resistance, high and low temperature resistance, UV resistance, and toughness of cable materials.

Description

Technical Field

[0001] This invention relates to the field of plasticizer processing technology for cables, specifically to a composite plasticizer for high and low temperature resistant cables and its preparation method. Background Technology

[0002] The use of plasticizers can be traced back to the late 19th and early 20th centuries. The earliest plasticizers were natural resins and vegetable oils, used to improve the plasticity of rubber and plastics. With the development of the chemical industry, synthetic plasticizers began to be widely used after the 1930s. Early plasticizers were mostly phthalates and epoxy esters, used to improve the softness and processing performance of PVC. Overall, plasticizers, as an important chemical, play a key role in modern industry. Continuous technological innovation and application research will help improve their efficiency and environmental friendliness.

[0003] The prior art (CN108699287A) discloses a plasticizer composition containing terephthalate esters and cyclohexane 1,4-diesters. Although the terephthalate esters and cyclohexane 1,4-diesters are optimized during the preparation process, it is still difficult to guarantee the impact of the bioaccumulation of terephthalate esters on the food chain. Furthermore, the temperature resistance of cyclohexane 1,4-diesters is relatively low, and they have high volatility, failing to maintain stability at high temperatures. Research has also revealed the following technical problems: the environmental friendliness of the terephthalate esters as the main plasticizer in this composition needs improvement, and the high-temperature resistance, chemical stability, and mechanical properties of the cyclohexane 1,4-diesters as an auxiliary catalyst all need to be improved.

[0004] To address this technical deficiency, a solution is proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a composite plasticizer for high and low temperature resistant cables and its preparation method, which solves the technical problem that the high and low temperature resistance and UV resistance of composite plasticizers for cables in the prior art need to be further improved.

[0006] The objective of this invention can be achieved through the following technical solution: a composite plasticizer for high and low temperature resistant cables, comprising 30-50 parts by weight of a main plasticizer, 20-40 parts by an auxiliary plasticizer, 20-40 parts by an auxiliary material, and 60-70 parts by a solvent;

[0007] The preparation method of the main plasticizer includes the following steps: adding modified citric acid polymer, modified chloroprene rubber, dimethyl sulfoxide and 0.1-0.5 mol / L aluminum chloride solution into a reaction vessel, raising the temperature of the reaction vessel to 40-60℃, keeping the reaction at this temperature for 2-4 hours, and then performing post-treatment to obtain the main plasticizer.

[0008] The main plasticizer synthesis reaction equation is:

[0009]

[0010] The principle of the synthesis reaction of the main plasticizer is as follows: under the catalysis of Lewis acid aluminum chloride, the chlorine group of the modified chloroprene rubber generates an intermediate with stronger electron affinity, R-Cl-AlCl3. The generated chloride intermediate undergoes a nucleophilic substitution reaction with the hydroxyl group (-OH) in the modified citric acid polymer. The oxygen anion in the hydroxyl group attacks the methylene carbon in the intermediate to form a transition state. After nucleophilic substitution, a main plasticizer linked by ether bonds is prepared.

[0011] Furthermore, the ratio of modified citric acid polymer, modified chloroprene rubber, dimethyl sulfoxide, and 0.1-0.5 mol / L aluminum chloride solution is 5-8 g: 2-3 g: 15-20 mL: 5-10 mL. The post-treatment includes: after the reaction vessel is cooled to room temperature, the reaction solution is added to a rotary evaporator with a water bath temperature of 80-100℃, and the mixture is distilled under reduced pressure until no liquid is collected, thus obtaining the main plasticizer.

[0012] Furthermore, the excipients comprise the following components by weight: 0.1-1 parts stabilizer, 5-15 parts solvent, 1-5 parts plasticizer activity modifier, and 5-20 parts filler; the stabilizer is one or more of zinc diester stabilizer, calcium-zinc heat stabilizer HX-10, and lead-free calcium-zinc stabilizer LX-800; the plasticizer activity modifier is one or more of diisooctyl phthalate, di(2-ethylhexyl) dibenzoate, dibutyl stearate, and di(2-ethylhexyl) benzoate; the filler is one or more of sodium carboxymethyl cellulose, hydroxypropyl methylcellulose, and glyceryl stearate; and the solvent is a mixture of ethanol and xylene in a mass ratio of 1-2:1.

[0013] Furthermore, the preparation method of the modified citric acid polymer is as follows: citric acid, 1,4-butanediol, dimethyl sulfoxide and 70-98 wt% sulfuric acid solution are added to a reaction vessel, the temperature of the reaction vessel is raised to 40-60℃, and the reaction is maintained for 2-4 hours. The modified citric acid polymer is then obtained after post-treatment.

[0014] The reaction equation for the synthesis of modified citric acid polymer is as follows:

[0015]

[0016] The principle of the modified citric acid polymer synthesis reaction is as follows: acidic conditions provide protons for the esterification reaction, which promotes the departure of hydrogen ions from the hydroxyl group of 1,4-butanediol, forming a good leaving group. This enhances the electrophilicity of the hydroxyl group, making it easier to attack the carbonyl carbon on the carboxyl carbon atom of citric acid. This allows citric acid and 1,4-butanediol phenol to be linked by ester bonds. The remaining hydroxyl group at the end then undergoes another esterification reaction with the remaining citric acid molecules to form a long-chain polymer.

[0017] Furthermore, the ratio of citric acid, 1,4-butanediol, dimethyl sulfoxide, and 70-98 wt% sulfuric acid solution is 8-10 g: 3-4 g: 10-15 mL: 5-10 mL. The post-treatment includes: after the reaction vessel is cooled to room temperature, the reaction solution is added to a rotary evaporator with a water bath temperature of 80-100℃ and distilled under reduced pressure until no liquid is collected, to obtain the modified citric acid polymer.

[0018] Furthermore, the preparation method of modified chloroprene rubber is as follows: chloroprene rubber with a molecular weight of 1000-1200, 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol, xylene, and 0.1-0.5 mol / L aluminum chloride solution are added to a reaction vessel at a ratio of 8-10 g:3-5 g:30-40 mL:5-10 mL. The temperature of the reaction vessel is raised to 40-60℃, and the reaction is maintained for 2-4 hours. After post-treatment, modified chloroprene rubber is obtained.

[0019] The reaction equation for the synthesis of modified chloroprene rubber is as follows:

[0020]

[0021] The principle of the modified chloroprene rubber synthesis reaction is as follows: Under the catalysis of Lewis acid aluminum chloride, the chlorine group of chloroprene rubber generates an intermediate with stronger electron affinity, R-Cl-AlCl3. The generated chloride intermediate undergoes a nucleophilic substitution reaction with the hydroxyl group (-OH) in 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol. The oxygen anion in the hydroxyl group attacks the methylene carbon in the intermediate to form a transition state. After nucleophilic substitution, a modified chloroprene rubber linked by ether bonds is prepared.

[0022] Further post-processing includes: after the reactor is cooled to room temperature, the reaction solution is added to a rotary evaporator with a water bath temperature of 80-100℃, and distilled under reduced pressure until no liquid is collected, to obtain modified chloroprene rubber.

[0023] Furthermore, the preparation method of the auxiliary plasticizer is as follows: add functional crosslinking agent, epoxidized soybean oil, triethylamine and N,N-dimethylformamide into a reaction vessel, raise the temperature of the reaction vessel to 60-80℃, keep the reaction at this temperature for 1-3 hours, and then perform post-treatment to obtain the auxiliary plasticizer.

[0024] The reaction equation for the synthesis of auxiliary plasticizers is as follows:

[0025]

[0026] The principle of auxiliary plasticizer synthesis reaction is as follows: Under weakly alkaline conditions, the hydroxyl groups (-OH) of the functional crosslinking agent and the epoxy groups in epoxidized soybean oil undergo a ring-opening reaction. The functional crosslinking agent and epoxidized soybean oil are polymerized by ether bond to modify benzene rings and phosphate groups inside the epoxidized soybean oil, thus preparing the auxiliary plasticizer.

[0027] Furthermore, the ratio of functional crosslinking agent, epoxidized soybean oil, triethylamine and N,N-dimethylformamide is 3-5g:10-12g:1-2g:40-50mL. The post-treatment includes: after the reaction vessel is cooled to room temperature, the reaction solution is added to a rotary evaporator with a water bath temperature of 80-100℃, and the solution is distilled under reduced pressure until no liquid is collected to obtain the auxiliary plasticizer.

[0028] Furthermore, the preparation method of the functional crosslinking agent is as follows: naphthol phosphate, 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane, triethylamine and N,N-dimethylformamide are added to the reaction vessel in a ratio of 8-10g:3-5g:0.5-1g:30-40mL. The temperature of the reaction vessel is raised to 60-80℃ and kept at this temperature for 1-3 hours. The functional crosslinking agent is then obtained after post-treatment.

[0029] The reaction equation for the synthesis of functional crosslinking agents is as follows:

[0030]

[0031] The principle of functional crosslinking agent synthesis reaction is as follows: under weakly alkaline conditions, the hydroxyl group (-OH) of naphthol phosphate and the epoxy group of 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane undergo a ring-opening reaction. Naphthol phosphate and 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane are polymerized by ether bond to prepare functional crosslinking agent.

[0032] Further post-processing includes: after the reactor is cooled to room temperature, the reaction solution is added to a rotary evaporator with a water bath temperature of 80-100℃, and the solution is distilled under reduced pressure until no liquid is collected, thus obtaining the functional crosslinking agent.

[0033] Furthermore, the preparation method of the composite plasticizer for high and low temperature resistant cables is as follows: the main plasticizer, auxiliary plasticizer, excipients and solvent are added to the reaction vessel and mixed evenly, and then passed through a 100-mesh sieve to obtain the composite plasticizer.

[0034] Furthermore, the cable material is prepared by adding polyvinyl chloride, composite plasticizer and auxiliary materials into a twin-screw extruder. The temperature of the eight temperature zones of the twin-screw extruder from the feed port to the discharge port is 160℃, 165℃, 165℃, 170℃, 170℃, 180℃ and 180℃ respectively. The main speed of the twin-screw extruder is 80-120 rpm and the pressure is 100-150 bar. The cable material is obtained by melt extrusion.

[0035] The present invention has the following beneficial effects:

[0036] 1. In the process of preparing a composite plasticizer for high and low temperature resistant cables, this invention involves preparing a primary plasticizer and an auxiliary plasticizer, which are then mixed with fillers to obtain the composite plasticizer. In the preparation of the primary plasticizer, citric acid is used as the base material, and 1,4-butanediol is used as the crosslinking agent to prepare a modified citric acid polymer. Then, 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol is used to treat low molecular weight chloroprene rubber. After modification, chloroprene rubber was grafted onto the modified citric acid polymer to prepare the main plasticizer. In the preparation of the auxiliary catalyst, naphthol phosphate was reacted with 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane to prepare a functional crosslinking agent, which was then further grafted onto the base material epoxidized soybean oil to prepare the auxiliary plasticizer. Through the synergistic effect of the main plasticizer, auxiliary plasticizer and excipients, a composite plasticizer that can enhance the wear resistance, high and low temperature resistance, UV resistance and toughness of cable materials was obtained.

[0037] 2. In the preparation of a composite plasticizer for high and low temperature resistant cables, this invention uses citric acid as the matrix material of the main plasticizer. A modified citric acid copolymer is formed using 1,4-butanediol as a crosslinking agent, creating a complex three-dimensional network structure. This complex network structure not only imparts excellent mechanical properties to the main plasticizer but also interacts with the numerous ester bonds formed, giving the main plasticizer extremely strong thermal stability. A modified chloroprene rubber is prepared by modifying low molecular weight chloroprene rubber with 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol. The low molecular weight chloroprene rubber can react with 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol... The synergistic interaction of UV-resistant groups endows the main catalyst with extremely high UV resistance. Following an organic reaction, a main plasticizer is prepared by linking modified chloroprene rubber and modified citric acid copolymer via ether bonds. The complex spatial network structure, in conjunction with the modified chloroprene rubber, gives the main plasticizer excellent wear resistance and toughness. The numerous ester bonds in the modified chloroprene rubber and the spatial network structure collectively enhance the heat resistance of the main plasticizer, giving it excellent thermal stability. The synergistic interaction of the UV-resistant groups in the modified chloroprene rubber and 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol significantly improves the UV resistance of the main plasticizer. Ultimately, a composite plasticizer main material is prepared that endows cable materials with excellent wear resistance, heat resistance, and UV resistance.

[0038] 3. In the process of preparing a composite plasticizer for high and low temperature resistant cables, this invention uses epoxidized soybean oil as the matrix material of the auxiliary plasticizer, and uses naphthol phosphate and 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane to prepare a functional crosslinking agent. Naphthol phosphate and 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane are linked through a ring-opening reaction. The silicon-oxygen bond of 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane interacts with the phosphate group and benzene ring in naphthol phosphate to give the auxiliary plasticizer extremely strong low temperature resistance. At the same time, the silicon-oxygen bond also enhances the crosslinking ability between organic and inorganic materials in the cable material preparation process, indirectly improving the wear resistance of the plasticizer. A further ring-opening reaction is used to link the functional crosslinking agent with epoxidized soybean oil. The abundant epoxy structure on the epoxidized soybean oil, together with the silicon-oxygen bonds, benzene rings, and phosphate groups on the functional crosslinking agent, enhances the low-temperature resistance of the auxiliary plasticizer. The abundant benzene ring structure on the auxiliary plasticizer also interacts with the complex spatial network structure in the main plasticizer, improving the wear resistance of the composite plasticizer. In the process of preparing cable materials using commonly used PVC resin, the abundant epoxy groups in the auxiliary plasticizer absorb hydrogen sulfide gas generated during the processing of polyvinyl chloride, making the cable preparation process more environmentally friendly. Through the above methods, a composite plasticizer auxiliary material with excellent wear resistance and low-temperature resistance for cable materials is finally prepared. Detailed Implementation

[0039] 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.

[0040] The polyethylene used in this invention has a density of 0.91-0.92 g / cm³. 3 It has a crystallinity of 48-52% and a molecular weight of 25,000-50,000.

[0041] Example 1

[0042] This embodiment provides a method for preparing a composite plasticizer for high and low temperature resistant cables, including the following steps:

[0043] S1. Preparation of the main plasticizer

[0044] 79.4 g of citric acid, 39.4 g of 1,4-butanediol, 99.3 mL of dimethyl sulfoxide and 99.3 mL of 75 wt% sulfuric acid solution were weighed and added to a reaction vessel. The temperature of the reaction vessel was raised to 40 °C and kept at this temperature for 2 h. After the reaction vessel was cooled to room temperature, the reaction solution was added to a rotary evaporator with a water bath temperature of 60 °C and distilled under reduced pressure until no liquid was collected, yielding 117.3 g of modified citric acid polymer.

[0045] 63.2 g of chloroprene rubber with a molecular weight of 1059.3, 39.5 g of 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol, 276.5 mL of xylene, and 79.0 mL of 0.1 mol / L aluminum chloride solution were weighed and added to a reaction vessel. The temperature of the reaction vessel was raised to 40 °C and the reaction was maintained at this temperature for 2 h. After the reaction vessel was cooled to room temperature, the reaction solution was added to a rotary evaporator with a water bath temperature of 80 °C and distilled under reduced pressure until no liquid was collected, yielding 98.3% modified chloroprene rubber.

[0046] 100.0 g of modified citric acid polymer, 60.0 g of modified chloroprene rubber, 300.0 mL of dimethyl sulfoxide and 100.0 mL of 0.1 mol / L aluminum chloride solution were weighed and added to a reaction vessel. The temperature of the reaction vessel was raised to 40 °C and kept at this temperature for 4 h. After the reaction vessel was cooled to room temperature, the reaction solution was added to a rotary evaporator with a water bath temperature of 80 °C and distilled under reduced pressure until no liquid was collected, yielding 156.3 g of the main plasticizer.

[0047] S2, Preparation of auxiliary plasticizers

[0048] Weigh 40.0 g of naphthol phosphate, 12.0 g of 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane, 2.0 g of triethylamine and 120.0 mL of N,N-dimethylformamide and add them to a reaction vessel. Raise the temperature of the reaction vessel to 60 °C and keep it at that temperature for 1 h. After the reaction vessel is cooled to room temperature, add the reaction solution to a rotary evaporator with a water bath temperature of 80 °C and distill under reduced pressure until no liquid is collected, to obtain 48.3 g of functional crosslinking agent;

[0049] Weigh out 36.0g of functional crosslinking agent, 72.0g of epoxidized soybean oil, 7.2g of triethylamine and 360.0mL of N,N-dimethylformamide and add them to the reaction vessel. Raise the temperature of the reaction vessel to 60℃ and keep it at that temperature for 1h. After the reaction vessel is cooled to room temperature, add the reaction solution to a rotary evaporator with a water bath temperature of 80℃ and distill under reduced pressure until no liquid is collected, to obtain 103.7g of auxiliary plasticizer.

[0050] S3, Preparation of composite plasticizers

[0051] Weigh out 1.9g of calcium-zinc heat stabilizer HX-10, 12.4g of dibutyl stearate and 49.7g of glyceryl stearate and mix them to prepare 64.0g of excipients;

[0052] Weigh 100.0g of primary plasticizer, 100.0g of secondary plasticizer, 64.0g of excipients, 100.0g of ethanol and 100.0g of xylene and add them to the reaction vessel. Mix them evenly and pass them through a 100-mesh sieve to obtain 462.5g of composite plasticizer.

[0053] S4. Preparation of cable materials

[0054] Weigh 1500.0g of polyvinyl chloride, 450.0g of composite plasticizer and 225.0g of auxiliary materials and add them to a twin-screw extruder. The temperature of the eight temperature zones of the twin-screw extruder from the feed port to the discharge port is 160℃, 165℃, 165℃, 170℃, 170℃, 180℃ and 180℃ respectively. The main speed of the twin-screw extruder is 80rpm and the pressure is 100bar. The cable material is obtained by melt extrusion.

[0055] Example 2

[0056] This embodiment provides a method for preparing a composite plasticizer for high and low temperature resistant cables, including the following steps:

[0057] S1. Preparation of the main plasticizer

[0058] 82.1 g of citric acid, 32.8 g of 1,4-butanediol, 123.2 mL of dimethyl sulfoxide and 82.1 mL of 85 wt% sulfuric acid solution were weighed and added to a reaction vessel. The temperature of the reaction vessel was raised to 40 °C and kept at this temperature for 2 h. After the reaction vessel was cooled to room temperature, the reaction solution was added to a rotary evaporator with a water bath temperature of 100 °C and distilled under reduced pressure until no liquid was collected, yielding 110.5 g of modified citric acid polymer.

[0059] 63.1 g of chloroprene rubber with a molecular weight of 1123.2, 25.2 g of 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol, 214.4 mL of xylene, and 50.5 mL of 0.5 mol / L aluminum chloride solution were weighed and added to a reaction vessel. The temperature of the reaction vessel was raised to 60 °C and the reaction was maintained at this temperature for 4 h. After the reaction vessel was cooled to room temperature, the reaction solution was added to a rotary evaporator with a water bath temperature of 100 °C and distilled under reduced pressure until no liquid was collected, yielding 84.5 g of modified chloroprene rubber.

[0060] 120.0 g of modified citric acid polymer, 45.0 g of modified chloroprene rubber, 300.0 mL of dimethyl sulfoxide and 120 mL of 0.5 mol / L aluminum chloride solution were weighed and added to a reaction vessel. The temperature of the reaction vessel was raised to 60 °C and kept at that temperature for 4 h. After the reaction vessel was cooled to room temperature, the reaction solution was added to a rotary evaporator with a water bath temperature of 100 °C and distilled under reduced pressure until no liquid was collected, yielding 158.3 g of the main plasticizer.

[0061] S2, Preparation of auxiliary plasticizers

[0062] 60.0 g of naphthol phosphate, 24.0 g of 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane, 4.85 g of triethylamine and 210.0 mL of N,N-dimethylformamide were weighed and added to a reaction vessel. The temperature of the reaction vessel was raised to 80 °C and the reaction was maintained at this temperature for 3 h. After the reaction vessel was cooled to room temperature, the reaction solution was added to a rotary evaporator with a water bath temperature of 100 °C and distilled under reduced pressure until no liquid was collected, yielding 82.3 g of functional crosslinking agent.

[0063] 36.0 g of functional crosslinking agent, 72.0 g of epoxidized soybean oil, 12.0 g of triethylamine and 288.0 mL of N,N-dimethylformamide were added to a reaction vessel. The temperature of the reaction vessel was raised to 80 °C and the reaction was maintained at this temperature for 3 h. After the reaction vessel was cooled to room temperature, the reaction solution was added to a rotary evaporator with a water bath temperature of 100 °C and distilled under reduced pressure until no liquid was collected, yielding 103.5 g of auxiliary plasticizer.

[0064] S3, Preparation of composite plasticizers

[0065] Weigh out 4.1g of calcium-zinc heat stabilizer HX-10, 15.3g of dibutyl stearate and 61.2g of glyceryl stearate and mix them to obtain 80.6g of excipients;

[0066] Weigh 108.0g of main plasticizer, 90.0g of auxiliary plasticizer, 72.0g of excipients, 128.0g of ethanol and 64.0g of xylene and add them to the reaction vessel. Mix them evenly and pass them through a 100-mesh sieve to obtain 458.5g of composite plasticizer.

[0067] S4. Preparation of cable materials

[0068] Weigh 1500.0g of polyvinyl chloride, 450.0g of composite plasticizer and 225.0g of auxiliary materials and add them to a twin-screw extruder. The temperature of the eight temperature zones of the twin-screw extruder from the feed port to the discharge port is 160℃, 165℃, 165℃, 170℃, 170℃, 180℃ and 180℃ respectively. The main speed of the twin-screw extruder is 120rpm and the pressure is 150bar. The cable material is obtained by melt extrusion.

[0069] Example 3

[0070] This embodiment provides a method for preparing a composite plasticizer for high and low temperature resistant cables, including the following steps:

[0071] S1. Preparation of the main plasticizer

[0072] 79.3g of citric acid, 26.4g of 1,4-butanediol, 105.7mL of dimethyl sulfoxide and 98wt% sulfuric acid solution were weighed and added to a reaction vessel. The temperature of the reaction vessel was raised to 50℃ and kept at that temperature for 3h. After the reaction vessel was cooled to room temperature, the reaction solution was added to a rotary evaporator with a water bath temperature of 90℃ and distilled under reduced pressure until no liquid was collected, yielding 102.6g of modified citric acid polymer.

[0073] 61.2 g of chloroprene rubber with a molecular weight of 1032.5, 27.2 g of 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol, 258.4 mL of acetone and 54.4 mL of 0.3 mol / L aluminum chloride solution were weighed and added to a reaction vessel. The temperature of the reaction vessel was raised to 50 °C and the reaction was maintained at this temperature for 3 h. After the reaction vessel was cooled to room temperature, the reaction solution was added to a rotary evaporator with a water bath temperature of 90 °C and distilled under reduced pressure until no liquid was collected, yielding 84.6 g of modified chloroprene rubber.

[0074] 100.0 g of modified citric acid polymer, 50 g of modified chloroprene rubber, 300.0 mL of dimethyl sulfoxide and 150.0 mL of 0.3 mol / L aluminum chloride solution were weighed and added to a reaction vessel. The temperature of the reaction vessel was raised to 50 °C and kept at that temperature for 3 h. After the reaction vessel was cooled to room temperature, the reaction solution was added to a rotary evaporator with a water bath temperature of 90 °C and distilled under reduced pressure until no liquid was collected, yielding 143.6 g of the main plasticizer.

[0075] S2, Preparation of auxiliary plasticizers

[0076] 64.0 g of naphthol phosphate, 32.0 g of 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane, 6.4 g of triethylamine and 288.0 mL of N,N-dimethylformamide were weighed and added to a reaction vessel. The temperature of the reaction vessel was raised to 70 °C and the reaction was maintained at this temperature for 2 h. After the reaction vessel was cooled to room temperature, the reaction solution was added to a rotary evaporator with a water bath temperature of 90 °C and distilled under reduced pressure until no liquid was collected, yielding 92.5 g of functional crosslinking agent.

[0077] 40.0g of functional crosslinking agent, 100.0g of epoxidized soybean oil, 18.0g of triethylamine and 420.0mL of N,N-dimethylformamide were added to a reaction vessel. The temperature of the reaction vessel was raised to 70℃ and the reaction was maintained at this temperature for 2 hours. After the reaction vessel was cooled to room temperature, the reaction solution was added to a rotary evaporator with a water bath temperature of 90℃ and distilled under reduced pressure until no liquid was collected, yielding 128.5g of auxiliary plasticizer.

[0078] S3, Preparation of composite plasticizers

[0079] Weigh out 2.6g of calcium-zinc heat stabilizer HX-10, 17.2g of dibutyl stearate and 64.5g of glyceryl stearate and mix them to prepare 84.3g of excipients;

[0080] Weigh 120.0g of primary plasticizer, 90.0g of secondary plasticizer, 80.0g of excipients, 130.0g of ethanol solvent and 65.0g of xylene and add them to the reaction vessel. Mix them evenly and pass them through a 100-mesh sieve to obtain 483.5g of composite plasticizer.

[0081] S4. Preparation of cable materials

[0082] Weigh 1500.0g of polyvinyl chloride, 450.0g of composite plasticizer and 225.0g of auxiliary materials and add them to a twin-screw extruder. The temperature of the eight temperature zones of the twin-screw extruder from the feed port to the discharge port is 160℃, 165℃, 165℃, 170℃, 170℃, 180℃ and 180℃ respectively. The main speed of the twin-screw extruder is 100rpm and the pressure is 125bar. The cable material is obtained by melt extrusion.

[0083] Comparative Example 1

[0084] The difference between this comparative example and Example 3 is that, in step S1, acetylacetic acid tributyl ester is used to replace the modified citric acid polymer in an equal amount.

[0085] Comparative Example 2

[0086] The difference between this comparative example and Example 3 is that, in step S3, an equal amount of acetylated tributyl citrate is used to replace the main plasticizer.

[0087] Comparative Example 3

[0088] The difference between this comparative example and Example 3 is that, in step S3, epoxidized soybean oil is used to replace the auxiliary plasticizer in an equal amount.

[0089] Comparative Example 4

[0090] The difference between this comparative example and Example 3 is that step S2 is omitted, and an equal amount of triglyceride phosphate is used to replace the auxiliary plasticizer.

[0091] Performance testing:

[0092] The acid gas content released during the preparation of cable materials using composite plasticizers in Examples 1-3 and Comparative Examples 1-4 was determined according to standard GB / T 2917.1-2002 "Determination of hydrogen chloride and any other acidic products at high temperature in blends and products mainly composed of vinyl chloride homopolymers and copolymers" during the cable material preparation process. The abrasion resistance, toughness, and high / low temperature resistance of the cable materials prepared using composite plasticizers in Examples 1-3 and Comparative Examples 1-4 were tested. Abrasion resistance was tested according to GB / T 17737.324-2018 "Coaxial communication cables - Part 1-324: Mechanical test methods - Abrasion resistance test". Toughness was tested according to GB / T 17737.316-2018 "Coaxial communication cables - Part 1-316: Mechanical test methods - Maximum tensile strength test". High temperature resistance was tested according to standard GB / T GB / T 2951.42-2008 "General Test Methods for Insulation and Sheath Materials of Cables and Optical Fibers - Part 42: Test Methods for Polyethylene and Polypropylene Blends" determines the tensile strength and elongation at break after high-temperature treatment, the winding test after high-temperature treatment, the winding test after air aging, the determination of mass increase, the long-term thermal stability test, and the copper catalytic oxidation degradation test method for determining the cracking of cables after high-temperature treatment and 42 days of insulation at 100℃; GB / T 2951.14-2008 "General Test Methods for Insulation and Sheath Materials of Cables and Optical Fibers - Part 14: General Test Methods - Low Temperature Test" determines the cracking of cables after being treated at -40℃. The flexibility and cracking after drop hammer impact of the cable material after 16 hours of low-temperature treatment at ℃ were assessed. The UV-resistant polyolefin cable materials of Examples 1-3 and Comparative Examples 1-4 were subjected to UV aging tests. The test conditions were: irradiation with a 5kW xenon lamp and water spraying at a pressure of 0.20MPa; cyclic UV irradiation was performed in 120-minute cycles, with 20 minutes of simultaneous water spraying and light irradiation, and the remaining 100 minutes of separate light irradiation, for a total of 1000 cycles. Afterwards, the samples were left to stand at room temperature for 24 hours, and the abrasion resistance, toughness, and high and low temperature resistance of the cable material were tested a second time. Specific test data are shown in Tables 1-3.

[0093] Table 1 - Release of acidic gases during sample preparation

[0094]

[0095] Table 2 - Performance Test Data of Samples

[0096]

[0097]

[0098] Table 3 - Performance test data of samples after ultraviolet cyclic irradiation

[0099]

[0100] Data Analysis:

[0101] Comparative analysis of the data in Table 1-2 shows that the process of preparing cable material using the composite plasticizer prepared in this experiment demonstrates that the abundant epoxy groups and other active functional groups within the cable material can effectively neutralize the hydrogen chloride gas released during the preparation of polyvinyl chloride, thus protecting the environment. The cable material prepared using the composite plasticizer prepared in this experiment has a blade abrasion resistance of 143 times, can be wound 8 times after high-temperature treatment, and did not crack after being kept at 100℃ for 42 days. After being kept at -40℃ for 16 hours, it can be wound 9 times and did not crack after a drop hammer impact test, with a tensile strength of 223 MPa.

[0102] Comparing the data from Example 3, Comparative Example 1, and Comparative Example 2, it can be found that the main plasticizer prepared in this experiment improves the high-temperature resistance, toughness, and wear resistance of the cable material through its excellent spatial structure, a large number of high-temperature resistant functional groups, and modified chloroprene rubber.

[0103] Comparing the data of Example 3, Comparative Example 3 and Comparative Example 4, it can be found that the auxiliary plasticizer prepared in this experiment significantly improves the low temperature resistance, toughness and wear resistance of the cable through its large number of low temperature resistant functional groups, epoxy groups and siloxy groups.

[0104] In summary, the composite plasticizer prepared through this experiment has a significant effect on improving the wear resistance, toughness, and high and low temperature resistance of cable materials.

[0105] Analysis of the data in Table 3 shows that the cable material prepared by using the composite plasticizer prepared in this experiment can withstand 125 blade abrasion cycles after 1000 cycles of ultraviolet radiation, can be wound 7 times after high temperature treatment, and does not crack after 42 days of heat preservation at 100℃. After 16 hours of low temperature treatment at -40℃, it can be wound 8 times and does not crack after drop hammer impact test. The tensile strength reaches 223MPa.

[0106] Comparing the data in the table, it can be found that, compared with Examples 1-3, Comparative Examples 3 and 4, Comparative Examples 1 and 2 showed a significant decrease in performance after being subjected to UV cycle radiation. This indicates that the complex spatial structure and UV-resistant groups in the prepared main plasticizer work synergistically to give the cable material prepared by using the composite plasticizer prepared in this experiment excellent UV resistance.

[0107] 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.

[0108] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0109] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A composite plasticizer for high and low temperature resistant cables, characterized in that, It includes 30-50 parts by weight of main plasticizer, 20-40 parts by auxiliary plasticizer, 20-40 parts by excipients and 60-70 parts by solvent; The preparation method of the main plasticizer is as follows: Modified citric acid polymer, modified chloroprene rubber, dimethyl sulfoxide and 0.1-0.5 mol / L aluminum chloride solution are added to the reaction vessel, the temperature of the reaction vessel is raised to 40-60℃, and the reaction is kept at this temperature for 2-4 hours. The main plasticizer is obtained after post-treatment. The excipients comprise the following components by weight: 0.1-1 parts stabilizer, 1-5 parts plasticizer activity modifier, and 5-20 parts filler; the stabilizer is one or more of zinc diester stabilizer, calcium-zinc heat stabilizer HX-10, and lead-free calcium-zinc stabilizer LX-800; the plasticizer activity modifier is one or more of diisooctyl phthalate, di(2-ethylhexyl) dibenzoate, dibutyl stearate, and di(2-ethylhexyl) benzoate; the filler is one or more of sodium carboxymethyl cellulose, hydroxypropyl methylcellulose, and glyceryl stearate; the solvent is a mixture of ethanol and xylene in a mass ratio of 1-2:

1. The modified citric acid polymer is prepared by adding citric acid, 1,4-butanediol, dimethyl sulfoxide and 70-98 wt% sulfuric acid solution into a reaction vessel, raising the temperature of the reaction vessel to 40-60℃, keeping the reaction at this temperature for 2-4 hours, and then performing post-treatment to obtain the modified citric acid polymer. The modified chloroprene rubber is prepared by adding chloroprene rubber with a molecular weight of 1000-1200, 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol, xylene, and 0.1-0.5 mol / L aluminum chloride solution to a reaction vessel at a ratio of 8-10 g:3-5 g:30-40 mL:5-10 mL. The temperature of the reaction vessel is raised to 40-60℃, and the reaction is maintained for 2-4 hours. The modified chloroprene rubber is then obtained after post-treatment. The preparation method of the auxiliary plasticizer is as follows: add functional crosslinking agent, epoxidized soybean oil, triethylamine and N,N-dimethylformamide into a reaction vessel, raise the temperature of the reaction vessel to 60-80℃, keep the reaction at this temperature for 1-3 hours, and then perform post-treatment to obtain the auxiliary plasticizer; The preparation method of the functional crosslinking agent is as follows: naphthol phosphate, 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane, triethylamine and N,N-dimethylformamide are added to a reaction vessel in a ratio of 8-10g:3-5g:0.5-1g:30-40mL. The temperature of the reaction vessel is raised to 80-100℃ and kept at this temperature for 1-3 hours. The functional crosslinking agent is then obtained after post-treatment.

2. The composite plasticizer for high and low temperature resistant cables according to claim 1, characterized in that, The ratio of modified citric acid polymer, modified chloroprene rubber, dimethyl sulfoxide, and 0.1-0.5 mol / L aluminum chloride solution is 5-8 g: 2-3 g: 15-20 mL: 5-10 mL. The post-treatment includes: after the reaction vessel is cooled to room temperature, the reaction solution is added to a rotary evaporator with a water bath temperature of 80-100℃ and distilled under reduced pressure until no liquid is collected to obtain the main plasticizer.

3. The composite plasticizer for high and low temperature resistant cables according to claim 1, characterized in that, The ratio of citric acid, 1,4-butanediol, dimethyl sulfoxide, and 70-98 wt% sulfuric acid solution is 8-10 g: 3-4 g: 10-15 mL: 5-10 mL. The post-treatment includes: after the reaction vessel is cooled to room temperature, the reaction solution is added to a rotary evaporator with a water bath temperature of 80-100℃ and distilled under reduced pressure until no liquid is collected, thus obtaining the modified citric acid polymer.

4. The composite plasticizer for high and low temperature resistant cables according to claim 1, characterized in that, The ratio of functional crosslinking agent, epoxidized soybean oil, triethylamine and N,N-dimethylformamide is 3-5g:10-12g:1-2g:40-50mL. The post-treatment includes: after the reaction vessel is cooled to room temperature, the reaction solution is added to a rotary evaporator with a water bath temperature of 80-100℃ and distilled under reduced pressure until no liquid is collected to obtain the auxiliary plasticizer.

5. A method for preparing a composite plasticizer for high and low temperature resistant cables as described in any one of claims 1-4, characterized in that, The preparation method of the composite plasticizer for high and low temperature resistant cables is as follows: add the main plasticizer, auxiliary plasticizer, excipients and solvent into the reaction vessel and mix evenly, then pass through a 100-mesh sieve to obtain the composite plasticizer.

Images