Hydrolysis of Kevlar fibres

Kevlar fibres were hydrolyzed in a concentrated aqueous solution of either sulphuric acid or sodium hydroxide. The hydrolyzed fibres were characterize d by measuring the tensile strength and the interlaminar sheer strength (IL SS). The active sites on the hydrolyzed surface were determined by the dyei ng-decolorizing method. The tensile strength of the hydrolyzed fibres decre ased with an increase in hydrolysis time and showed a turning point. The al kaline hydrolysis improved the ILSS by about 4%, while acid hydrolysis show ed insignificant improvement. From the experimental results, the better hyd rolyzing condition is by treating the fibres in 10 M NaOH at 100 degreesC f or 5 h.