Research and Comparison of Applications of PPTA Polyparaphenylene Terephthalamide Fibers in Composites

Polyparaphenylene terephthalamide (PPTA) fibers, with the trade name Kevlar, are made from a combination of strong and lightweight para-aramid with other aramids such as Nomex and Technora. This fiber is an organic compound containing carbon, hydrogen, oxygen, and nitrogen and contains both aromatic and amide molecular groups. The amide groups form hydrogen bonds between the polymer chains, which results in a very strong chemical structure. The aromatic structure is radially oriented, providing a greater degree of symmetry and strength to the internal structure of Kevlar fibers. As a result, it has a crystalline arrangement with polymer chains parallel to the fiber axis. Kevlar fibers are typically in the form of chopped fibers, yarns, or woven fabrics and are used as a component of composite materials. The advantages of these fibers include low weight, low density, high tensile strength, low thermal expansion, high thermal resistance or fire resistance, high degradation temperature, and appropriate energy absorption characteristics and dielectric or non-conductive properties, which have made them more widely used in a variety of composites than other fibers such as carbon and glass fibers. In this research, Kevlar fibers are examined and compared with other fibers such as carbon and glass fibers and their use in composites by conducting tests such as determining thermal resistance, physical properties, and determining the specific surface area, shape, and size of pores using the BET method. As a result, Kevlar fibers are introduced as a fiber with a wide range of uses, suitable properties, and low cost compared to other synthetic fibers.

کلیدواژه ها:

Kevlar fibers ، tensile strength ، thermal resistance ، multilayer composites