The Preparation of Thermostable Fiber From Condensed Polynuclear Aromatic (COPNA) Resint

Abstract

A continuous filament yarn was made from the B stage resin with a softeing point of 45 °C. This resin named COPNA resin was prepared using a mixture of 1-methylnaphthalene (α-MN) and 1, 4-benzenedimethanol (PXG) of 2.5 times in molar ratio to α-MN. The continous filament yarn was immersed and cured in over 95% conce ntrated sulfuric acid for a few minutes to prevent it from melting and reacting at higher temperature. The cured filament yarn was then washed with water and dried in air. The cured filament yarn was insoluble and infusible, and did not deform even when the fiber was heated at 300°C in air. The mechanical properties o f the cured filament were measured. The tensile strength was ca.250 MPa and the Young 's modulus was ca.6 GPa. The carbonized filament yarn obtained by heating at 2500°C in a stream of argon was mechanically fragile. The filament yarn from a pitch based resin was continously made by the use of 2, 5dmithyl-1, 4-benzene dimethanol (DMPXG) as a crosslinking agent. This filament had a mechanical strength of ca.490 MPa in tensile strength and ca.5 GPa in Young's modulus by immersing and curing the filament yarn in sulfuric acid in a manner similar to theα-MN based filament yarn.