PROCESSING AND CHARACTERIZATION OF CARBON FIBRE-REINFORCED POLYNAPHTHOXAZINE COMPOSITE

摘要

In order to attain a high-temperature resistant composite with good performance as well as processability, a polynaphthoxazine composite with 60% by volume of carbon fibre has been successfully developed. The naphthoxazine monomer was modified to obtain lower melting point and higher solubility for improved processability. The density and void content of this composite were measured at room temperature. The T-g and the activation enthalpy of the glass transition process were measured by dynamic mechanical analysis, and the effect of cure temperature on the T-g of the composite was studied. The thermal characteristics of this composite were studied in terms of the weight loss after isothermal ageing, the decomposition temperature from thermogravimetric analysis, and the change in dynamic storage moduli at high temperatures. Flexural and interlaminar shear tests were performed to evaluate the mechanical properties of this composite. A good balance between strength and toughness of this composite was achieved. A very high char yield of 90% was gained after carbonization in a nitrogen atmosphere. This polynaphthoxazine composite compares favourably with the bismaleimide composites in terms of mechanical properties and thermal stabilities. [References: 23]