Oriented films from recycled poly(ethylene terephthalate)/recycled high-density polyethylene compatibilized blends

摘要

The process for the compatibilized blending of recycled poly(ethylene terephthalate) and recycled high-density polyethylene with ethylene/glycidyl methacrylate copolymer was enlarged to the scale of a pilot plant. The addition of a compatibilizer effectively reduced the size of dispersed inclusions with better bonding to the matrix. The optimum contents of the compatibilizer were found to be around 4 pph. The extrusion and orientation of films from the blend were developed on an industrial scale, and the structure and properties of the obtained films were characterized. The crystalline phase of poly(ethylene terephthalate) in oriented films assumed a strong texture resulting from the plane-strain state of the deformation of the films on the industrial machinery. The origin of the texture was mostly strain-induced crystallization. The chain segments in the amorphous phase were oriented along the machine direction, but there was significant anisotropy of the chain packing in the amorphous phase in the plane perpendicular to the drawing direction, the pseudohexagonal packing of chain fragments being in register over the whole film. Such a texture of an oriented amorphous phase of poly(ethylene terephthalate) is reported here for the first time. The nonoriented and oriented films obtained with the industrial machinery showed good mechanical properties, with strengths up to 120 MPa and elongations to break of 40%. (C) 2002 Wiley Periodicals, Inc. [References: 28]