Difference Between High Density Polyethylene and Low Density Polyethylene

I. Different production processes

The production processes of HDPE and LDPE are different, so they differ in molecular structure and physical properties. In the process of producing HDPE, Ziegler-Natta catalyst is used and reacted under high pressure, which makes the molecular weight of polyethylene molecular chain very high, the degree of crystallinity is high and the density is relatively high; while LDPE is manufactured under low pressure and high temperature, the molecular weight is low, the molecular chain is more dispersed and the density is relatively low.

Second, different properties and characteristics

The physical properties of high-density polyethylene are relatively more superior, such as mechanical strength, pressure resistance, abrasion resistance, rigidity, chemical resistance and other aspects of outstanding performance, while there is a high temperature resistance and flame retardant, the cost is also relatively high. While low-density polyethylene shows good flexibility and ductility, while more transparent, easy to process, and relatively low price.

Third, different application areas

Due to the differences in the nature and characteristics of the two polythene materials, they have their own focus in the field of application. HDPE is mainly used in products that require firmness and hardness, such as bottle caps, plastic buckets, water pipes, cables, etc., while LDPE is mainly used in products that require flexibility and transparency, such as cling film, plastic bags, toys, medical equipment, etc.

In summary, HDPE and LDPE are different in terms of production process, property characteristics and application areas, etc. It is hoped that this article has provided readers with a better understanding of these two polyethylene forms.