Thermoplastics are one of the most widely used plastics and are formulated with plastics as the main component of a thermoplastic resin and with various additives. Thermoplastic plastic resin chains are linear or branched structure, no chemical bonds between the molecular chains, in a certain temperature conditions, can be softened or melted into any shape, the same shape after cooling; this state can be Repeatedly and always has plasticity, and this repetition is just a physical change.
Common thermoplastics are the following:
Polyvinyl chloride (PVC)
Other polyolefins and their copolymers
Through the modification of plastics and the addition of fibrous substances in plastics, the following properties of ordinary plastics can be greatly improved:
1. Improve the mechanical strength, such as tensile, bending, compression, elastic modulus and creep resistance;
2, increase the heat distortion temperature;
3, reduce the linear expansion coefficient;
4, reduce water absorption, increase the dimensional stability;
5, increase the hardness;
6, inhibit stress cracking.
Various thermoplastics have different reinforcing effects, among which the most significant and most widely used are polyamides, and polyvinyl chloride, polycarbonate, ABS, polyethylene, polypropylene and other reinforcing effects are also very good.
Reinforcing fiber material
Thermoplastic reinforced fiber materials must have high strength, low elongation, good rigidity, small creep, excellent heat resistance and other characteristics, mainly include: glass fiber, carbon fiber, basalt fiber, aramid fiber and so on.
Among them, glass fiber is the most widely used and has the largest amount, because glass fiber not only meets the above characteristics, but also is suitable for industrial production with low price and wide source. It is the most important raw material of fiber-reinforced thermoplastics (FRTP).