Equal‐channel multiangular extrusion of semicrystalline polymers

Potentialities of a new simple shear-based scheme of the solid-phase extrusion of polymers, named the equal channel multiple angular extrusion (ECMAE), for modification of semicrystalline polymer structure have been investigated by the example of low- and high-density polyethylene (LDPE, HDPE), polyamide-6 (PA-6), and polytetrafluoroethylene (PTFE). The effects of velocity and extrusion temperature, plastic deformation intensity, and accumulated equivalent plastic strain value on properties of a number of crystallizing polymers have been studied. It has been shown that the highest strength characteristics are attained for the extrusion temperatures of (0.8–0.95) of the melting temperature and deformation velocity of (0.6–1.1) mm s−1. For the ECMAE-processed specimens, the density, the enthalpy, and the melting temperature have become higher. In the oriented structure of semicrystalline polymers formed by the ECMAE, the lamellae are oriented along the extrudate axis. POLYM. ENG. SCI., 2010. © 2010 Society of Plastics Engineers