ANELASTIC DEFORMATION OF A THERMOPLASTIC-MATRIX FIBER-COMPOSITE AT ELEVATED-TEMPERATURE .2. TIME-TEMPERATURE DEPENDENT MATRIX BEHAVIOR

The tensile deformation and failure behavior, dynamic mechanical prope rties and creep behavior of PACM-12 (DuPont, poly(bis 4-4' dicyclohexy lmethane) n-dodecanediamide), a representative thermoplastic polymer f or use as a matrix in advanced composites and as an engineering plasti c, as a function of processing history are described. Although injecti on molded PACM-12 fails in a brittle fashion at room temperature, comp letely amorphous PACM-12 is ductile; the difference is attributed to v ariations in cooling in the interior of the samples due to sample thic kness effects. Partially crystalline samples are brittle at room tempe rature, with all samples being ductile near and above T(g). A master c reep curve for the partially crystalline samples can be obtained by ho rizontal shift alone.