Differences in Core PE Grades

PE is an indispensable raw material in the plastics industry, including blown film, blow molding, and injection molding. The market is flooded with various PE grades, and many industry players cannot distinguish the essential differences between high-density and low-density polyethylene (HDPE) and linear polyethylene. Blindly purchasing these grades can easily lead to problems such as brittleness, softness, poor shape retention, and processing difficulties in the finished product.

Today, we summarize the five most frequently used PE grades in the plastics industry, providing a comprehensive comparison of their parameters, performance, and applications. This practical information will help you avoid making mistakes when selecting materials.

I. HDPE (High-Pressure Polyethylene)

1. 5502
   Density: 0.954
   Melt Flow Index: 0.25
   Core Properties: Ultra-high rigidity, high hardness, acid and alkali resistance, corrosion resistance, dense structure, and extremely high stiffness; Weakness: Moderate toughness, prone to brittleness in low-temperature environments.

Applicable Scenarios: Primarily used in hollow blow molding, chemical drums, oil cans, daily chemical bottles, and large hollow containers.

2. 5000S
   Density: 0.950
   Melt Index: 0.9
   Core Properties: Balanced rigidity and toughness, high tensile strength, good wear resistance, strong processing stability, and high overall cost-effectiveness.
   Applications: Filament, woven bags, ropes, mesh materials, general injection molded daily necessities, extruded products.
3. 8008H
   Density: 0.950
   Melt Index: 8
   Core Properties: High flowability + high rigidity, dimensional stability, not prone to warping, superior toughness compared to ordinary low-density polyethylene, resistant to low-temperature cracking.
   Applications: For thin-walled injection molding, beverage bottle caps, plastic pump heads, turnover boxes, small auto parts, storage products.

II. LLDPE (Linear Low-Density Polyethylene)

4. 7042
   Density: 0.920
   Melt Index: 2.0
   Core Properties: Outstanding toughness, tear resistance, puncture resistance, low-temperature resistance, good ductility, an excellent toughening and improving raw material.

Applications: Various packaging films, express delivery bags, agricultural films, stretch films; often blended with HDPE to solve the problem of brittleness in rigid materials.

III. LDPE (Low-Pressure Polyethylene)

5. 2426H
   Density: 0.922
   Melt Flow Index: 2.0
   Core Properties: Soft texture, strong waxy surface, high transparency, excellent heat-sealing performance, smooth processing and not easily broken.

Applications: Food preservation film, supermarket shopping bags, composite soft films, lightweight packaging film products.