Source: Flickr

Thermoplasticity refers to the property of certain materials to become more pliable and malleable when heated and retain their new shape once cooled down. Thermoplastics can be melted and reshaped several times without suffering significant changes or degradation of their molecular structure.

Thermoplastic materials actually encompass a whole array of different plastics with different mechanical properties, all of which share that one fundamental property. In this article, we’ll discuss different types of thermoplastics and their respective properties and advantages.

Types of Thermoplastics

Listing all the different types of thermoplastics would be a tedious job since there are over a hundred different types with unique properties. However, we’ll list the types most commonly used by different industries.

• Polythene/Polyethylene — Perhaps one of the best-known and mass-produced thermoplastics, as it’s used for product packaging. It can be classified as high-density polyethylene (HDPE) or low-density polyethylene (LDPE). The former is used for plastic bottles and food containers, while the latter is used for plastic bags and films.
• Polycarbonate (PC) — PC is a strong, transparent type of plastic that has excellent impact resistance and can withstand high levels of stress without breaking. It’s used for the fabrication of bullet-proof glass, DVDs, eyewear lenses, smartphone components, greenhouse panels, and similar durable products.
• Acrylic — Most commonly used as an alternative to glass, acrylic is most often used in windows, fish tanks, and bike helmet visors due to its rigidity and high impact resistance.
• Polyamide — Better known as nylon, polyamide is an extremely tough material with a high abrasion resistance and resistance to corrosion and impact. It’s used in sporting equipment, 3D printing, footwear, and medical products.
• Polystyrene — Gained by modifying styrene with rubber, which grants the material great impact resistance. One flaw is that this material is flammable, however, flame-retardant versions also exist. This type of plastic is non-toxic and FDA-approved for storing consumable goods.
• Polypropylene — Polypropylene is a very flexible thermoplastic polymer with great chemical resistance to acids, a very high melting point, and high impact resistance. Due to its versatility, PP is used by various industries, such as the automotive and aerospace industry, for making parts that need to bend into position.
• Acrylonitrile Butadiene Styrene — Commonly known as ABS, this plastic material boasts some fantastic physical properties. It can be modified during the production process to produce the exact properties specified by the manufacturer. This includes high-temperature resistance, tensile strength, and impact resistance.
• Polyester — This thermoplastic is perhaps best known for its use in clothing, but it's also used for conveyor belts, seat belts, bed covers, electrical insulation coatings, and more.
• Polyvinyl Chloride — Gained from vinyl chloride monomer through polymerization, PVC is a thermoplastic resin with fantastic physical properties, such as chemical resistance, toughness, and durability, making it a very popular material for a wider range of applications.

Advantages of Thermoplastics

Besides being extremely durable and moldable at high temperatures, thermoplastics are also available at high volume at a relatively low cost, which is why they’re among the most popular materials used by designers and engineers. However, they aren’t without other benefits, such as:

• High-impact resistance
• Recyclable
• Visually aesthetic
• Good chemical resistance
• Good heat resistance
• Good Shore hardness scale

Choosing Thermoplastics for Industrial Use

There are more than a hundred thermoplastics available; in this guide, we listed some of the most commonly used thermoplastic materials to help you make an informed decision about your next project. If you want to learn more about thermoplastics or other types of materials, check out our Engineering Resources or download free CAD models of the parts you might be interested in.