S. Rhee et Jl. White, Investigation of double bubble tubular film extrusion of polyamide 6 and film structural characteristics, POLYM ENG S, 39(7), 1999, pp. 1160-1175
Biaxially oriented polyamide 6 films were made by double bubble tubular fil
m extrusion. The crystalline character and biaxial orientation of the films
were investigated by measuring (in plane and out of plane) birefringences,
IR (infrared) spectroscopy, and wide angle X-ray diffraction (WAXS) flat f
ilm patterns and pole figures. The samples were also examined by tensile st
retching tests in different sampling directions.