Preparation and characterization of quartz fiber/polyamide-46 composites

To prepare one kind of composites with excellent mechanical properties, which would be used in long load-bearing bone repairing, different contents of quartz fiber (QF )with mass ratio of 30wt% and 45wt% were used to enhance polyamide-46 (PA46) and QF/PA46 composites were prepared by extrusion and injection molding. The structure, interface, mechanical performance and nonisothermal crystallization behavior of composites were studied by using burning test, FTIR, XRD, SEM and DSC. The results show that QF is uniformly distributed in composites and is quasi-isotropic. QF and PA46 matrix are mainly linked by hydrogen bond. The crystallinity of materials decreases with increasing QF contents. QF enhances the crystallization growth rate of PA46 and contributes to heterogeneous nucleating agent, but the interface action between QF and PA46 hinders the molecules' order arrangement, which decreases the crystallization degree. The crystallization peaks of PA46 and QF/PA46 move from higher temperature to lower with the increase of cooling rate, meanwhile, the width of crystallization peak becomes larger. The mechanical test indicates that more QF (within a certain limits) in composites leads to an increase in tensile strength and bending strength, which are close to those of the natural compact bone. The cytotoxicity test (adopting L929 fibroblast) shows that cytotoxicity level of the composites is grade 1, indicating it has a better biological safety. The QF/PA46 composites have potential application in long load-bearing bone repairing.