CN-119529446-B - High-elasticity high-stability PVC granules and preparation method and application thereof

Abstract

The invention belongs to the technical field of modification of high polymer materials, and relates to a high-elasticity high-stability PVC pellet, a preparation method and application thereof in medical catheters. The granules are prepared by taking 100 parts of PVC resin powder, 50-60 parts of plasticizer, 5-10 parts of epoxidized soybean oil, 0.6-1.5 parts of composite heat stabilizer, 0.4-6 parts of elastomer, 0.4-0.8 part of processing aid and 0.1-0.4 part of lubricant as raw materials, and carrying out melt extrusion by an extruder after the raw materials are pre-plasticized, and granulating and molding. The pellet is subjected to melt secondary extrusion molding to obtain a high-elasticity high-stability medical catheter body, and the medical catheter body can be assembled to obtain a medical catheter product, wherein the medical catheter product comprises an infusion medical catheter, a nursing medical catheter or an implantation medical catheter. The high-elasticity high-stability PVC granules have excellent elasticity, tensile toughness, thermal stability and long-term stability, and can endow the catheter with excellent elasticity and stability when applied to medical catheter products.

Inventors

• ZHAO PAN
• GAO YU
• WANG GUOFENG
• WANG GUOSHENG
• ZHANG XINZHE
• Kong Mengwei
• WANG GUOCHAO
• LIU ZHIYUAN

Assignees

• 河南省驼人医疗科技有限公司

Dates

Publication Date

20260508

Application Date

20241216

Claims (2)

1. 1. The preparation method of the high-elasticity high-stability PVC granules is characterized by comprising the following steps of: S1, mixing solid raw materials, mixing liquid raw materials with the solid raw materials in batches, controlling a mixing process to obtain a pre-plasticizing raw material, S2, carrying out melt extrusion and granulation molding on the pre-plasticizing raw material by an extruder, wherein: S11, adding the solid raw materials into a high-mixing pot, setting the mixing rotating speed to be 200-300rpm, adding 50% -80% of liquid raw materials after the solid raw materials are heated to 50-80 ℃, S12, adding the rest liquid raw materials after the temperature is raised back to 65-85 ℃, continuously stirring and heating to 90-110 ℃, setting the mixing rotating speed to be 700-900rpm, and finally cooling to 45-65 ℃ after the temperature of the materials is raised to 120-135 ℃; The granulating condition of the extruder in the S2 is that the rotating speed of a main machine is 260+/-20 rpm, the feeding speed is 160+/-20 rpm, the granulating speed is 250+/-20 rpm, and the extruding temperature is 80-120 ℃; the main raw materials of the high-elasticity high-stability PVC granules comprise 100 parts of PVC resin powder, 50-60 parts of plasticizer, 5-10 parts of epoxidized soybean oil, 0.6-1.5 parts of composite heat stabilizer, 0.4-6 parts of elastomer, 0.4-0.8 part of processing aid and 0.1-0.4 part of lubricant, wherein the raw materials are calculated by weight; The composite heat stabilizer comprises 5-7 parts of main stabilizer and 3-5 parts of auxiliary stabilizer, wherein the main stabilizer consists of zinc stearate and calcium stearate in a mass ratio of 1:1-5, the auxiliary stabilizer comprises diisooctyl phosphite, and the elastomer comprises chlorinated polyethylene, PVC elastomer or nitrile rubber in parts by weight; The processing aid is formed by compounding acrylic ester copolymers with different molecular weights, wherein the acrylic ester copolymers are ACR copolymers, the different molecular weights refer to high molecular weight, medium molecular weight and low molecular weight, wherein the ACR copolymer with the high molecular weight is PA-40, the ACR copolymer with the medium molecular weight is PA-20, the ACR copolymer with the low molecular weight is PA-101, the compounded ACR copolymers are compounded by PA-40, PA-20 and PA-101 in a mass ratio of 2:2:1, or the PA-40 and PA-101 in a mass ratio of 3:1, or the PA-20 and PA-101 in a mass ratio of 3:1; the PVC resin powder has an average polymerization degree of 1800-2500, the plasticizer comprises diisooctyl terephthalate, dioctyl adipate or trioctyl trimellitate, and the lubricant comprises any one or more of oxidized polyethylene wax, stearic acid and benzyl silicone oil; The solid raw materials comprise PVC resin powder, zinc stearate and calcium stearate in a stabilizer, a processing aid, oxidized polyethylene wax and stearic acid in a lubricant and PVC elastomer in an elastomer, and the liquid raw materials comprise a plasticizer, epoxidized soybean oil, diisooctyl phosphite in the stabilizer, chlorinated polyethylene and liquid nitrile rubber in the elastomer and benzyl silicone oil in the lubricant.
2. 2. Use of the high-elastic high-stability PVC pellet prepared in the method for preparing high-elastic high-stability PVC pellet as claimed in claim 1 for preparing medical catheter tube or catheter.

Description

High-elasticity high-stability PVC granules and preparation method and application thereof Technical Field The invention belongs to the technical field of modification of high polymer materials, and relates to a high-elasticity high-stability PVC pellet, a preparation method and application thereof in medical catheters. Background Polyvinyl chloride (PVC) is one of five general plastics in the world, is widely applied to various fields, has the second yield, and has excellent insulating and flame-retardant properties. Because the PVC produced in the traditional industrial field at present inevitably has certain defect structures, the PVC can generate yellowing, discoloration and other degradation processes under the external actions of light, oxygen, heat and the like in the use process, so that the original performance of the PVC is reduced, and the use of the PVC is limited. There is therefore a need for an improvement in the thermal stability of PVC. The PVC degradation is generally considered to be dehydrochlorination of PVC molecular chains, and double bonds are formed on the molecular chains to accelerate the degradation of PVC. Along with the dehydrochlorination reaction, the conjugated double bonds on the molecular chain of the PVC are gradually increased, which is shown by the color change and the color deepening of the PVC material, and in addition, the hydrogen chloride released by the degradation of the PVC has a catalytic effect on the degradation of the PVC, so that the degradation of the PVC is further accelerated. Through patent and literature investigation, the main way of carrying out heat stabilization modification on the PVC material in the prior art is to rapidly replace allyl chloride on a PVC molecular chain, inhibit the growth of conjugated double bonds, fundamentally improve the heat stability of PVC, prevent PVC from changing color, and timely absorb hydrogen chloride released by PVC degradation, prevent the catalysis of the PVC degradation, thereby slowing down the degradation of PVC. The main method for improving the heat stability of PVC at present is to add a certain amount of heat stabilizer to delay the thermal degradation of PVC. Examples of the heat stabilizer which is commonly used include lead salts, metal soaps, organotin-based heat stabilizers, rare earth-based heat stabilizers, and the like. However, lead salt heat stabilizers used in the traditional industrial production are too high in toxicity, easy to cause heavy metal pollution, poor in compatibility of metal soap heat stabilizers and resin matrixes, high in processing difficulty, high in price of organic tin heat stabilizers, heavy in smell during processing and easy to cause pollution, and rare earth heat stabilizers are limited in use due to control. The research of nitrogen-containing organic heat stabilizers is focused by researchers, but most of the organic heat stabilizers are small molecular compounds, precipitation phenomenon is easy to occur in the small molecular heat stabilizers, the improvement effect on the PVC heat stability is general, meanwhile, the initial whiteness is general, the color of the main body of the PVC heat stabilizer can sometimes influence the color of PVC products, and the long-term stability is insufficient. Different products of the PVC base material have different performance and functional requirements on materials and products, such as high transparency, high elasticity and the like, and when the special functions are realized on the products, the performances of the materials are often damaged, the tensile toughness of the materials is poor and the like, so that the application development of the PVC base material on medical products with higher performance requirements is restricted, such as the problem that the medical catheter is extruded and deformed due to the demands of stock and the like in the production and storage process, the product is folded due to poor material elasticity, the assembly bonding is further influenced, and the dissolution phenomenon is caused in severe cases, and if the situation occurs in the blood transfusion process of patients, the life safety of the patients is threatened. Therefore, improving the long-term thermal stability of the PVC material and improving the elastic performance of the PVC material can be very important for improving the performance and applying the PVC material. Disclosure of Invention Based on the above, the invention aims to provide a high-elasticity high-stability PVC pellet, which has excellent elastic performance, heat stability and long-term stability. The invention also provides a preparation method of the high-elasticity high-stability PVC granules and application of the PVC granules in medical equipment products. In order to achieve the above purpose, the present invention adopts the following technical scheme: The invention provides a high-elasticity high-stability PVC pellet, which comprises, by weight, 100 par