HDPE Melting Point, Repeat Unit, Properties, Advantages & Disadvantages
Name and Identification of the Polymer –
HiTec, Playboard, Paxon, King Colorboard , Densetec, Polystone, King PlastiBal, and Plexar.
Thermo-Physical Properties –
|Melting Point||130 °C (266°F)|
|Density||0.960 g mL-1|
|Heat Deflection Temperature, 0.5 MPa||72 °C|
|Heat Deflection Temperature, 1.8 MPa||77 °C|
|Coefficient of Thermal Expansion x 10-5||14 cm °C|
|Thermal Conductivity||0.42 W/ mk|
|Shore Hardness, D Scale||55-67|
Mechanical Properties –
|Tensile Strength, Break at 23 C||32 MPa|
|Tensile Strength, Yield at 23 C||26 MPa|
|Tensile Modulus at 23 C||900-1500 MPa|
|Flexural Modulus||970-1250 MPa|
71-155 J/m (kJ/m2)
|Izod Unnotched||No Break J/m|
Electrical Properties –
2.1-3.5 V/mm x 104
6 x 1015 Ohm-cm
|Dielectric Constant @ 1 MHz||2.2-2.4|
|Dissipation Factor @ 1 MHz||0.0001 – 0.0005|
HDPE is a beneficial material with many salient advantages. Let us have a look at some of them:
- One of HDPE’s standout features is its malleability and moldability, which improves its applications substantially in the infrastructure industry. A good example is the underground piping sector, where HDPE is the most preferred plastic material, thanks to its good weatherability and long-lastingness.
- HDPE has an outstanding strength to weight ratio of 0.93 to 0.97 g. That might not seem very impressive compared to LDPE. However, HDPE’s more linear structure with little branching gives it an edge over LDPE with greater tensile strength and greater molecular structure.
- It is corrosion-resistant, has good rigidity, and has a high melting point of 130 to 210°C. It’s difficult to melt, but its liquid form is easily processable to manufacture products like water tanks, shampoo bottles, cutting boards, detergent bottles, etc.
- It is easily recyclable and doesn’t lose its ability a slightest after being recycled. In fact, the recycled material is said to be as good as virgin material.
- Non-resistant to chlorinated hydrocarbons.
- Non-resistant to oxidizing acids.
- High flammability
- High thermal expansion
1. Is HDPE safe to melt?
Ans. HDPE doesn’t get sticky once melted and can’t be easily removed once it cools down and while burning. If not added with any additives, it will burn clean and won’t release any toxic fumes. However, when you add pigments, antioxidants, antistats, and other lubricants, the outcome differs, and toxic fumes are released. So, in a nutshell, it’s fine to burn HDPE using general laboratory equipment.
2. What type of material is HDPE?
Ans. HDPE comes from a polyethylene family of thermoplastics and is produced from the monomer ethylene. Therefore, it is also sometimes referred to as “alkathene” or “polythene” when used for HDPE pipes.
3. Why HDPE melting point is higher than LDPE?
Ans. HDPE has a more linear and crystalline structure, and LDPE is softer and more flexible. Their fundamentally different internal composition results in differences in many physical attributes, and melting point is one of them.
4. Why is HDPE being used more in Hospitals?
Ans. HDPE is becoming very popular these days for healthcare and medical applications. Its salient features include high impact resistance, low moisture absorption, corrosion resistance, chemical resistance, and easy processing. Hospitals rely on HDPE to create cost-effective and dependable medical devices that don’t splinter, rot, and retain bacteria.
5. Can I recycle HDPE and LDPE together?
Ans. Unlike other plastics, HDPE and LDPE are miscible to be recycled together, but it is advisable to recycle them separately to keep their physical properties intact.
The Conclusion –
That was all I had to say about HDPE melting point, properties, repeat unit, advantages & disadvantages. The reason for choosing to write this piece was that HDPE is still one of the most popular thermoplastics in the world, and keeping track of the most basic things can sometimes be very crucial to accomplish big things.
Thanks for bearing with my awful writing 🙂 Share your thoughts and questions in the comment box.
Have an outstanding day ahead 🙂