HDPE and PVC

Plastic materials are very elastic and malleable. They can be moulded, pressed or cast into different shapes. They are mainly made of oil and natural gas. There are two types of plastics; thermoplastics and thermoset polymers.

While thermoset polymers can only be melted and shaped once and remain solid once cooled, thermoplastics can be melted and shaped repeatedly and are therefore recyclable.

Thermoplastics are used to make containers, bottles, fuel tanks, folding tables and chairs, sheds, plastic bags, cable insulators, bulletproof panels, pool toys, upholstery, clothing and plumbing.

There are several types of thermoplastics, and they are classified as amorphous or semi-crystalline. Two of them are amorphous PVC (polyvinyl chloride) and semi-crystalline HDPE (high density polyethylene). Both are commodity polymers.

Polyvinyl chloride (PVC) is an inexpensive and durable vinyl polymer used in construction projects. It is the third most widely used plastic after polyethylene and polypropylene and is widely used in the production of pipes. It is lightweight and strong, making it very popular in above-ground and underground plumbing applications. It is very sturdy and suitable for direct burial and trenchless installation.

On the other hand, high density polyethylene (HDPE) is a polyethylene thermoplastic made from petroleum. It has higher strength, is harder, and can withstand high temperatures.
HDPE pipes are convenient for use in underground pipes, as they have been found to dampen and absorb shock waves, thereby minimizing surges that can affect the system. They also have the best joint compression resistance and are more abrasion and heat resistant.

While both materials are strong and durable, they vary in strength and other aspects. On the one hand, they are designed to withstand different stresses. To achieve the same pressure rating as PVC pipe, HDPE pipe wall must be 2.5 times thicker than PVC pipe.

While both materials are also used to make fireworks, HDPE has been found to be more suitable and safer to use because it can fire the fireworks to the proper height. If it fails to start inside the container and breaks, the HDPE container will not break with as much force as the PVC container.

To summarize:

1. Polyvinyl Chloride (PVC) is an inexpensive and durable vinyl polymer used in construction projects, while High Density Polyethylene (HDPE) is a polyethylene thermoplastic made from petroleum.
2. Polyvinyl chloride is the third most widely used plastic, and polyethylene is one of the most widely used plastics.
3. PVC is amorphous, while HDPE is semi-crystalline.
4. Both are strong and durable, but with different strength and different applications. PVC is heavier and stronger, while HDPE is harder, more abrasion-resistant and more heat-resistant.
5. HDPE pipes have been found to suppress and absorb shock waves, thereby minimizing surges that can affect the system, while PVC cannot.
6. HDPE is more suitable for low pressure installation, while PVC is more suitable for direct burial and trenchless installation.