Method for preparing thermal stabilizer/lubricant for polyvinyl chloride profiles

Abstract

The invention discloses a method for preparing thermal stabilizer / lubricant for polyvinyl chloride profiles. The method comprises the following steps: firstly reacting part of stearic acid, part of salicylic acid and part of diglycol in a reactor to prepare an auxiliary agent 1; reacting another part of stearic acid, the rest of salicylic acid and the rest of diglycol in the reactor to prepare an auxiliary agent 2; heating part of yellow lead, the rest of stearic acid and paraffins to react in another reactor to prepare an intermediate; reacting the rest of yellow lead, glacial acetic acid and cyanuric acid in the reactor and grinding to prepare a synthetic material; reacting part of the prepared intermediate, the synthetic material and part of the auxiliary agent 1 to prepare a composite; heating and reacting the composite, the rest of intermediate, the rest of auxiliary agent 1, the auxiliary agent 2, bisphenol A and a brightening agent in a kneading machine; and carrying out extrusion molding.

Description

technical field [0001] The invention relates to a preparation method of a thermally stable lubricant for polyvinyl chloride profiles. Background technique [0002] Polyvinyl chloride is also called PVC. Its molecules are relatively polar molecules. Due to the large intermolecular force, its softening temperature and melting temperature are high, and its glass transition temperature is high. Therefore, it generally needs to be heated to above 150-160°C. In order to make it plasticized, the processing temperature is usually between 160 and 210 °C. However, PVC resin is extremely unstable to heat. It is easy to degrade and dehydrochloride at the processing temperature. This reaction causes PVC to produce polyene sequences of colored conjugated double bonds, resulting in discoloration, brittleness and corrosion of equipment. In severe cases, it will make processing impossible. [0003] In order to inhibit the dehydrochlorination reaction of PVC due to degradation and ensure th...

AI Technical Summary

Problems solved by technology

However, the traditional tri-salt and di-salt monomer heat stabilizers are powdery, and there are disadvantages such as backward production technology, large energy consumption, many operating procedures during use, repeated weighing or grinding before use; in PVC resin Poor dispersibility, undispersed white spots, difficult to control the internal quality of the product, large dosage, low thermal stability efficiency, general processability; serious toxic lead dust flying in the process of production and use, not only very harmful to human health , and pollute the environment

[0005] Domestic production of dust-free composite lead-salt stabilizers has not started since the 1980s. Although this stabilizer has solved the problem of flying lead-salt dust, the design concept has not deviated from the traditional three-salt and two-salt as the main heat stabilizer. Mode, the processing technology is to physically mix various monomers and then press them into sheets. Due to poor quality and low grade, it can only be used for low-grade and low-quality PVC products.