There are two types of plastics, thermoplastic and thermoset polymers. Thermoset polymers can only be melted and molded once and remain solid once cooled. Thermoplastics can be repeatedly melted and shaped to be recycled. Both PVC and HDPE are thermoplastics that have much in common: such as lightweight, corrosion resistant, bacteria and chemical accumulation. Both are commercial polymers, so in some cases they can be used interchangeably.
But they are not exactly the same. Thermoplastics are again classified as amorphous or semi-crystalline. Among them, PVC (polyvinyl chloride) is an amorphous plastic, and HDPE (high density polyethylene) is a semi-crystalline plastic. They each have their own characteristics and advantages. Here describes their different features.
1. Different characteristics
Polyvinyl chloride (PVC), light weight and high strength, is ideal for above-ground and underground pipeline applications. Because it is very rugged, it is suitable for both direct and non-excavation installations. High density polyethylene (HDPE) is a polyethylene thermoplastic made from petroleum. It has higher strength, is harder, and can withstand high temperatures. HDPE piping is easy to use in underground pipelines because it suppresses and absorbs shock waves, minimizing surges that can affect the system. HDPE tubes also have optimum joint pressure resistance for better wear and heat resistance.
2. Different connection methods
PVC plastics are joined by gaskets or gluing sealants, while HDPE is joined by hot melt. In some cases, PVC materials can be glued or stitched under water, while HDPE cannot.
3. Installation speed is different
The assembly of HDPE pipes requires well-trained operators and expensive energy-intensive equipment. Fusing HDPE pipes together is more expensive and requires additional generators. The installation of PVC pipes is much faster.
4. Different degrees of convenience
HDPE is not suitable for repeated installation and removal, and is not folded and stored like PVC.
5. Different pressure capacity
The HDPE pipe wall must be 2.5 times thicker than the PVC pipe to reach the same rated pressure as the PVC pipe. HDPE was found to be more suitable for use in the manufacture of fireworks because it is safer and can fire the fireworks shell to the right height.
6. Different prices
Polyvinyl chloride (PVC) is an inexpensive and durable vinyl polymer commonly used in construction projects, while high density polyethylene (HDPE) is a polyethylene thermoplastic made from petroleum and is more expensive than PVC.
7. Different applications
PVC is heavier and stronger, while HDPE is harder, more wear resistant and heat resistant. This is very important when buildings use HDPE in a manufacturing or agricultural environment. HDPE is more resistant to salt, corrosive materials and sand, straw and dust, making it an ideal choice for farm and industrial buildings.
8. Different lengths of use
PVC tarpaulins provide an instant and inexpensive cover for many items around the home, but for longer life and higher work, HDPE is more suitable. Many HDPE overlays have a rated life of 20 years or more, while PVC tarpaulins harden and crack under sunlight and may not last for three years.
In a word, although PVC and HDPE many have many common points, they are two quite different materials and have they own features. If you are considering to buy one, you’d better choose them according to their characteristics and make the wisest choices.
EAGLE Company specializes in the development and manufacture of HDPE/PVC profiles, tanks and related accessories with proven technology and core equipment. If you have a need on HDPE or PVC, please contact us in time, we will try our best to provide you with a satisfactory service to meet your existing needs.