Nucleation and Crystallization of PA6 Composites Prepared by T-RTM: Effects of Carbon and Glass Fiber Loading

Polymers

Agnieszka Tercjak¹  Nerea Zaldua²  Jon Maiz²  AlejandroJ. Müller²  Sonia García-Arrieta³  Amaia de la Calle³  Isabel Harismendy³  Cristina Elizetxea³ 

[1] Group ‘Materials + Technologies’ (GMT), Department of Chemical and Environmental Engineering, Faculty of Engineering, Gipuzkoa, University of the Basque Country, UPV/EHU, Plaza Europa 1, 20018 Donostia-San Sebastián, Spain;POLYMAT and Polymer Science and Technology Department, Faculty of Chemistry, University of the Basque Country, UPV/EHU, Paseo Manuel de Lardizábal 3, 20018 Donostia-San Sebastián, Spain;TECNALIA, Parque Tecnológico de San Sebastián, Mikeletegi Pasealekua 2, Donostia, E-20009 San Sebastián, Spain;

关键词: thermoplastic;    caprolactam;    glass fibers;    carbon fibers;    crystallization;    elastic modulus;    tensile strength;   

DOI  :  10.3390/polym11101680

来源: DOAJ

【 摘 要 】

Thermoplastic resin transfer molding (T-RTM) is attracting much attention due to the need for recyclable alternatives to thermoset materials. In this work, we have prepared polyamide-6 (PA6) and PA6/fiber composites by T-RTM of caprolactam. Glass and carbon fibers were employed in a fixed amount of 60 and 47 wt.%, respectively. Neat PA6 and PA6 matrices (of PA6-GF and PA6-CF) of approximately 200 kg/mol were obtained with conversion ratios exceeding 95%. Both carbon fibers (CF) and glass fibers (GF) were able to nucleate PA6, with efficiencies of 44% and 26%, respectively. The α crystal polymorph of PA6 was present in all samples. The lamellar spacing, lamellar thickness and crystallinity degree did not show significant variations in the samples with or without fibers as result of the slow cooling process applied during T-RTM. The overall isothermal crystallization rate decreased in the order: PA6-CF > PA6-GF > neat PA6, as a consequence of the different nucleation efficiencies. The overall crystallization kinetics data were successfully described by the Avrami equation. The lamellar stack morphology observed by atomic force microscopy (AFM) is consistent with 2D superstructural aggregates (n = 2) for all samples. Finally, the reinforcement effect of fibers was larger than one order of magnitude in the values of elastic modulus and tensile strength.

【 授权许可】

Unknown