HDPE: is defined by a density of greater or equal to 0.941 g/cm3. HDPE has a low degree of branching and thus stronger intermolecular forces and tensile strength. PE-UHMW is not melt processable, because of its extremely high viscosity. It can be processed by ram extrusion and compression molding.
Key Points: With HDPE properties can be tailored by controlling the molecular weight distribution or by generating very high or very low MW species.
APPLICATIONS OF HDPE
Agriculture
Drip irrigation drippers, sprinkler parts, agricultural nets, pipes for irrigation.
Automobile
Fuel tank, petrol and lubricating oil containers, propellers for boats, break handles.
Electrical
Insulation for electrical and telephone wires
Furniture
Chairs, chair handles & table
Household
Buckets, mugs, trays, soap boxes, tubes and pipes, bowls, water tanks, dust bins, suitcases, toys
Industrial
Chemical storage tanks, gasoline tank impellers, pipes and fittings for chemical and gas transportation
Packaging
Containers for dairy products, bottle caps, milk crates, containers for pesticides, woven sacks for packaging of grains and powder products.
Strengths:
1. Higher notched impact strength than other PE
2. Higher wear resistance than other PE
3. Higher energy absorption capacity at high stress rates than other PE
4. Higher heat deflection temperature than other PE
5. Higher stress crack resistance than other PE
6. Very low water absorption FDA compliant
7. Good thermal stability
8. Tg is well below room temperature
9. High tensile strength, stiffness, creep resistance, abrasion resistance than LDPE
10. Non-polar in nature
11. Very good chemical resistance
Limitations:
1. Not melt processable
2. Higher Cost than PE
Properties
1. Very good chemical resistance
2. High tensile strength, stiffness, creep resistance, abrasion resistance than LDPE
3. Tg is well below room temperature
4. Excellent low temperature toughness
5. Good thermal stability
6. Non-polar in nature
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