Preparation method of linear low density polyethylene

Abstract

The invention relates to a preparation method of linear low density polyethylene. The preparation method comprises the following steps: 1, taking methyl methacrylate and benzoyl peroxide, adding polyisobutylene, and reacting to obtain methyl methacrylate grafting polyisobutylene at 85-105DEG C, wherein the weight of the methyl methacrylate accounts for 5-15% of the weight of polyisobutylene, and the weight of the benzoyl peroxide accounts for 1-5% of the weight of polyisobutylene; 2, taking methyl methacrylate grafting polyisobutylene, an organic anti-block agent stearamide, a dispersant zincstearate and an oxidant beta-(3,5-di-t-butyl-4-hydroxyphenyl)propionic acid n-octadecyl alcohol ester, wherein the weight of methyl methacrylate grafting polyisobutylene accounts for 3-15% of the weight of the linear low density polyisobutylene, the weight of the organic anti-block agent accounts for 0.1-1% of the weight of the linear low density polyisobutylene, the weight of the dispersant accounts for 0.05-0.5% of the weight of the linear low density polyisobutylene, and the weight of the antioxidant accounts for 0.1-0.5% of the weight of the linear low density polyisobutylene; and 3, mixing above materials in a high speed mixer, and extruding by a double screw extruder to prepare a low density polyethylene film. The method has the advantages of low cost, high softness, good stability and high speed printing performance.

Description

technical field [0001] The invention relates to a preparation method of linear low-density polyethylene with high softness and high printability. Background technique [0002] Packaging is a very active field, with new products emerging all the time. In the field of packaging, the consumption potential of plastic flexible packaging is huge. High flexibility, high printability LLDPE resin is a special resin mainly developed for the field of flexible packaging. In order to obtain flexible packaging materials with high product quality and excellent performance, it is required that the polymer chain of the plastic substrate should have good flexibility, so that the polymer chain or segment has a good diffusion effect under the action of higher temperature Ability, and the mechanical properties such as elongation at break of raw materials are required to be better. Flexible packaging printing based on plastic film occupies an important position in packaging printing. It requi...

AI Technical Summary

Problems solved by technology

[0005] At present, the softening additive used in polyethylene PE is mainly ethylene-octene copolymer POE, which can improve the softness of PE, but there are certain problems. Since no polar groups are introduced, it needs to be blown into a film. Only by adding a process of increasing the polarity of the film can the film product be easily printed at high speed, the process is very complicated, and the cost will be correspondingly increased

Therefore, the existing technology cannot improve the softness and high-speed printability of the film at the same time before blowing the film