Polyamide 66 Polymorphic Single Polymer Composites

Exploring the polymorphism phenomenon of polyamide 66 (PA 66) a single polymer composite (SPC) was prepared. The matrix was obtained via compression molding and quenching in ice water expecting to comprise the modi- fication with lower melting temperature (Tm). The reinforcement was commercial textile yarn of PA 66, characterized by a higher Tm. Layers of the yarn were sandwiched between matrix films and compression molded at 250 °C, i.e. 10 °C below Tm of the reinforcement. SEM observations revealed the layered structure of SPC as well as a good adhesion between the composite components due to surface premelting. The tensile testing showed, as compared with the matrix, an increase of the initial modulus by 28% and of the tensile strength by 160% when the reinforcing component of the SPC amounted to only 20 wt%. Optimization of the preparation conditions, including variation of the matrix/reinforcement ratio as well as trialing of other polyamides, is in progress.