Organic polymer fibers include aramid (aromatic polyamide) and polyethylene terephthalate (PET) fibers. Aramid fibers usually exist in the form of chopped and surface treated fibers. The composite material made of aramid fiber is especially suitable for the situation where high damping is required. Because of the low compressive strength of these fibers, they are easy to wear (shorten) when composite; therefore, the mechanical properties of aramid fiber composite are not obvious, especially when considering its cost. Aramid fiber is not straight rod like glass fiber or carbon fiber, but curly or twisted. This feature makes the aramid fibers in Aramid composites not fully oriented along the flow direction during processing, so the distribution of properties in all directions is more uniform. Plastic sheet production line www.handern.com
Pet chopped fiber bundles can be mixed with glass fiber to improve the impact strength of brittle resin matrix. Although PET fiber can not provide the mechanical strength or hardness of the composites, its cost is lower than that of other glass fiber reinforced components, and the abrasion effect of PET fiber on the mold surface is also lower than that of glass fiber. Plastic sheet production line www.handern.com
Kevlar fiber is a kind of aramid fiber, which was industrialized by DuPont company in 1972. It has super rigid molecular chain and super high modulus. Through many experiments, the tensile modulus of the wet spun fiber is more than 50gpa (353cn / dtex), which is two and a half times higher than that of glass fiber. Under the same mass, the fiber is more rigid than glass fiber. In 1970, DuPont blades invented the dry jet wet spinning process, which increased the fiber strength by two times and the spinning speed by four times. Since then, DuPont started the industrialization of aromatic polyamide fiber, and then commercial named Kevlar. The difference from general polyamide is that the main chain of polymer is mainly aliphatic group and cyclic aliphatic group. Plastic sheet production line www.handern.com
Aromatic polyamide fibers include Kevlar, no mex, conex, technora and Twaron. The two kinds of fibers developed in China in the early 1980s have the same structure as Kevlar fiber, named aramid 1414 and aramid 14, which are collectively called aramid fiber.