一、The main difference between LDPE (low density polyethylene) and HDPE (high density polyethylene) lies in their density, physical properties, uses, etc.
1. Density and appearance:
The density of LDPE is usually between 0.910-0.940g/cm³, while the density of HDPE is between 0.940-0.976g/cm³.
LDPE has a milky white appearance and is translucent to a certain extent in thin sections, while HDPE is generally opaque and has a milky white and translucent appearance.
2. Physical properties:
LDPE is relatively soft, has good toughness, good transparency, and slippery feel. It has poor dimensional stability during molding and processing, and is difficult to connect.
HDPE has high strength, good toughness, and strong rigidity, close to PP (polypropylene), tougher than PP, and has good temperature resistance.
3.Use:
LDPE has low melt viscosity, good fluidity, and is easy to process. It is suitable for the production of drinking water pipes, etc.
HDPE is suitable for making drawing grade, injection molding grade, hollow grade and blown film grade products, such as fishing nets, beverage bottles and packaging bags.
4. Chemical resistance:
Both have excellent resistance to most domestic and industrial chemicals, but HDPE is more resistant to acid, alkali corrosion and organic solvents.
5. Heat resistance and aging resistance:
LDPE has poor heat resistance, aging resistance and environmental stress cracking resistance as HDPE, and is prone to aging, decomposition and discoloration.
HDPE has good high temperature resistance but poor low temperature resistance. The disadvantage is that its aging resistance and environmental stress cracking resistance are not as good as LDPE.
二、The main differences between PP and PE materials are as follows:
1. Ingredients: The main component of PP is polypropylene, while the main component of PE is polyethylene.
2. Characteristics: PP is usually a translucent colorless solid, odorless and non-toxic, with high heat resistance, transparency, mechanical strength and other characteristics; PE is a recognized food contact material in the world, non-toxic, tasteless, It is odorless, feels like wax, complies with hygiene standards for food packaging, has good ductility, is not easily damaged, and has excellent heat sealability.
3. Scope of use: PP can be used to make greenhouse air awnings, mulch films, culture bottles, etc., and can also be used to make food turnover boxes, food bags, etc. PE can be processed by blow molding, extrusion, injection molding and other methods, and is widely used in the manufacture of films, hollow products, etc.
Post time: May-15-2024