DEVELOPMENT AND CHARACTERIZATION OF GLASS FIBER REINFORCED IN-SITU POLYMERIZED THERMOPLASTIC MATRIX COMPOSITE MATERIAL

摘要

This work is aimed at the development and characterization of glass fiber reinforced thermoplastic matrix composite material. High melt viscosities of thermoplastic matrices have traditionally hindered their application as a matrix system for the development of composite materials by liquid composite molding. A novel matrix system consisting of cyclic butylene terephthalate (CBT) oligomers and a suitable catalyst has been used for the development of glass fiber reinforced thermoplastic matrix composite material in this study. The injection and impregnation parameters were determined by differential scanning calorimetry and rheometry analysis of oligomers in the presence of different proportions of the catalyst. After injection and impregnation of textile structures, the ultra-low viscosity CBT oligomers are capable of ring opening in-situ polymerization toward polybutylene terephthalate (PBT). The characterization of the thermoplastic matrix showed an excellent conversion rate of low molecular weight oligomers to high molecular weight polymer. The scanning electron microscopy elucidated good impregnation quality and fiber wet-out. The dynamic mechanical thermal analysis revealed the viscoelastic characteristics of the in-situ polymerized CBT and the glass fiber reinforced thermoplastic composite material.