Astro Advice
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When selecting materials for project, it’s important to consider the effects of density, melt index and molecular weight on polyethylene. The following chart will help you with material selection:
| Property | As Density Increases Property | As Melt Index Increases Property |
| Tensile Strength(at yield) | Increases | Decreases |
| Stiffness | Increases | Decreases slightly |
| Impact Strength | Decreases | Decreases |
| Low Temperature Brittleness | Worsens | Worsens |
| Abrasion Resistance | Increases | Decreases |
| Hardness | Increases | Decreases Slightly |
| Softening Point | Increases | . |
| Stress Crack Resistance | Decreases | Decreases |
| Permeability | Decreases | Increases Slightly |
| Chemical Resistance | Increases | Decreases |
| Melt Strength | . | Decreases |
| Gloss | Increases | Increases |
| Haze | Decreases | Decreases |
| Shrinkage | Increases | Decreases |