Preparation And Properties Of High Young's Modulus PA9T Composites

Nylon 9T(PA9T)is a kind of high-strength,low-absorbency,high-temperature polymer produced by polycondensation of nonanediamine and terephthalic acid,can replace non-ferrous materials.In terms of replacing metal materials to achieve light weight,PA9 T still needs to be modified.In order to improve the mechanical properties and dimensional stability of PA9 T,the effects of attapulgite,sepiolite,glass fiber on PA9 T Young's modulus,tensile strength,dimensional stability,water absorption and other properties have been studied in this paper.As the process parameters are very critical to the final quality of the plastic parts,the influence of the injection molding process parameters on the dimensional stability of PA9 T have been studied,expecting to prepare a kind of high Young's modulus,dimensional stability PA9 T composite.In this paper,the properties of PA6/PA9 T alloy were studied.The results showed that PA6 could undergo an amide exchange reaction with PA9 T,destroying the regularity of the molecular chain and inhibiting the crystallization of the material,but the mechanical properties of the alloy material were not changed significantly.PA6 could be used as a carrier to prepare filled masterbatch.The effect of attapulgite and sepiolite on the mechanical properties of PA9 T was studied comparatively.Since the Young's modulus of PA6 and PA9 T was little increased by adding the nucleating agent,this paper then studied the effect of inorganic filler modification on the mechanical properties of PA9 T.In order to enhance the reinforcement of the inorganic filler on PA9 T,the effects of the masterbatch method and the one-step method on the properties of the composite material were discussed.The results showed that PA9 T composites made with PA6 as the carrier resin owed better mechanical properties.Then,PA6 as the carrier resin,the effects of attapulgite and sepiolite on the performance of PA9 T were comparatively studied.The results showed that Young's modulus of PA9 T could be effectively increased by both attapulgite and sepiolite,but when the amount of attapulgite reached over 5 wt%,the tensile strength of PA9 T was decreased,while at the same content of sepiolite the tensile strength of PA9 T was still being increased with the increasing of sepiolite content.In order to further improve the Young's modulus of PA9 T and obtain composite materials with high dimensional stability,the glass fiber was ground into powder,screened with a 100 mesh screen,and then made into a composite masterbatch with sepiolite.The synergistic effect of glass fiber and sepiolite on PA9 T mechanical properties,crystallization performance and dimensional stability was studied.The results showed that the Young's modulus of PA9 T could be synergistically increased by glass fiber and sepiolite,but the tensile strength was not significantly improved.When the content of Sep reached 5 wt% and GF reached 35 wt%,the mechanical properties of PA9 T were optimal.The crystallinity,dimensional shrinkage of the composite material decreased with increasing sepiolite content,indicating that sepiolite could improve the dimensional stability of PA9 T more effectively than glass fiber.