PP vs PE Case
PP (polypropylene) and PE (polyethylene) are both common case materials. PP is harder, more rigid, used for cases. PE is softer, more flexible, used for bags and liners. Both are food-safe, recyclable, and cost-effective.
Detailed Comparison
| Aspect | Pp | Pe |
|---|---|---|
| Density | 0.91 g/cm³ | 0.92-0.96 g/cm³ |
| Tensile strength | 30-40 MPa | 20-30 MPa |
| Hardness (Shore D) | 70-80 | 50-65 |
| Heat deflection | 100°C | 65-80°C |
| Chemical resistance | Excellent | Good |
| Recycling code | 5 | 4 (LDPE) or 2 (HDPE) |
| Cost | Lower | Higher |
| Best for | Cases, rigid packaging | Bags, liners, flexible packaging |
Verdict
Choose PP for: cases, rigid packaging, higher temperature. Choose PE for: bags, liners, flexible packaging, lower temperature. For cases, PP is standard. For inner liners, PE is common.
Are PP and PE the same?
No. PP and PE are different polymers with different properties. PP is harder, more rigid, used for cases. PE is softer, used for bags and films. Both are recyclable but with different codes (5 vs 2/4).