Tensile behaviour of some high performance filaments after sulphuric acid treatment

Quartz, aramid, and glass filaments were treated by sulphuric acid with various concentrations and periods. During the treatment, temperature of the acid was changed accordingly. Tensile behaviour of the treated fibres was tested and analyzed; it was shown that the tensile strength of the treated fibres was greatly decreased. The outward appearance of the treated filaments was shown.