Polyethylene is the simplest macromolecular organic compound and the most widely used macromolecular material in the world today. It is made by polymerizing ethylene and is divided into high-density polyethylene, medium-density polyethylene, and low-density polyethylene according to different densities.

Introduction

Low-density polyethylene is softer and is mostly polymerized by high pressure.

High-density polyethylene has the characteristics of rigidity, hardness and high mechanical strength and is mostly used for low-pressure polymerization.

High-density polyethylene can be used as containers and pipes, as well as high-frequency electrical insulation materials for radar and television.

Main functions

Low-density (high-pressure) polyethylene is often used in large quantities. Polyethylene is waxy and has a waxy smoothness. When not dyed, low-density polyethylene is transparent, while high-density polyethylene is opaque. Polyethylene is a high-polymer chain formed by repeated -CH2- units linked by addition reaction and polymerization reaction of ethylene (CH2=CH2). The performance of polyethylene depends on its polymerization method; high-density polyethylene (HDPE) is formed by Ziegler-Natta polymerization under the catalytic conditions of organic compounds at medium pressure (15-30 atmospheres). The polyethylene molecules polymerized under this condition are linear, and the molecular chain is very long, with a molecular weight of up to hundreds of thousands. If it is free radical polymerization under high pressure (100-300MPA), high temperature (190-210C) peroxide catalysis, low-density polyethylene (LDPE) is produced. It is a PE plastic bag with a branched structure.

Polyethylene is insoluble in water and has very low water absorption. Even for some chemical solvents, such as toluene and acetic acid, it is only slightly soluble at temperatures above 70буC. However, micro-particle polyethylene can also melt or solidify with changes in temperature between 15буC and 40буC. It melts when the temperature rises and absorbs heat; it solidifies when the temperature drops and releases heat. Because it absorbs very little water, is not easy to get wet, and has insulating properties, it is a good building material.

Characteristics

PE bag weight = L (cm) * w (cm) * T (cm) * 0.155 * 0.00263 / 2.2046

Expression method of PE bag size: the opening size is at the front and the thickness is at the back.

PE bag width = square tube side length * 2.5

Structural formula

CH2=CH2+CH2=CH2-CH2---CH2---CH2

Abbreviation: CH2=CH2---{CH2---CH2---CH2}

Polymerization pressure: high pressure, medium pressure, low pressure;

Polymerization implementation method: slurry method, solution method, gas phase method;

Product density: high density, medium density, low density, linear low density;

Product molecular weight: low molecular weight, ordinary molecular weight, ultra-high molecular weight;

Classification function

Ordinary PE plastic bag production environment is completed without environmental factory requirements and applied to use without special requirements.

Medical PE plastic bags

The production environment of medical PE plastic bags is completed in the dust-free grade inspection requirements. The raw materials, production workshop and packaging workshop are completely isolated to ensure the high quality and high cleanliness requirements of medical PE plastic bags.

Dust-free PE plastic bags

The production environment of dust-free PE plastic bags and the quality of raw materials directly affect the cleanliness requirements of plastic bags. Dust-free plastic bags are produced in a fully enclosed clean room to ensure that the plastic bags are not contaminated

Silicon-free PE plastic bags

Silicon-free PE plastic bags are cut in a dust-free environment to ensure that the surface of the plastic bags is free of pollution and the cleanliness requirements of the plastic bags are guaranteed.

Sterile PE plastic bags

The production environment of sterile PE plastic bags is completed in a Class 100 environment. During the production process of sterile plastic bags, the raw materials and production workshops are separated to avoid external contamination of sterile plastic bags during the production process. The cutting workshop of sterile plastic bags adopts high-intensity ultraviolet sterilization to ensure the sterile quality of plastic bags.

Application scope

Application fields:

1 Medical device packaging, medical product packaging, sterile product packaging, dust-free product packaging

2 Electronic industry parts packaging, direct contact product inner packaging

3 Semiconductors, optical instrument packaging, dust-free room product packaging

4 Hard disk drives, hardware product outer packaging, component packaging

5 Product outer packaging, product packaging without special requirements, and other industries

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