Low temperature solid‐state extrusion of recycled poly(ethylene terephthalate) bottle scraps

Abstract

The processing of poly(ethylene terephthalate) (PET) involves thermal and hydrolytic degradation of the polymer chain, which reduces not only the intrinsic viscosity and molecular weight, but also the mechanical properties of recycled materials. A novel PET/bisphenol A polycarbonate/styrene-ethylene-butylene-styrene alloy based on recycled PET scraps is prepared by low temperature solid-state extrusion. Hydrolysis and thermal degradation of PET can be greatly reduced by low temperature solid-state extrusion because the extrusion temperature is between the glass-transition temperature and cold-crystallization temperature of PET. Modification of recycled PET by low temperature solid-state extrusion is an interesting method; it not only provides an easy method to recycle PET scraps by blend processing, but it can also form novel structures such as orientation, crystallization, and networks in the alloy.

Thermal properties and morphology of recycled poly(ethylene terephthalate)/maleic anhydride grafted linear low‐density polyethylene blends

“…In our previous work, low-temperature solid-state extrusion technology was investigated intensively, which is different from other kinds of extrusion. [17][18][19] The hydrolytic degradation and thermal degradation of PET result in poor mechanical properties. For recycled PET, it is difficult to maintain its mechanical properties after melt extrusion.…”

“…For recycled PET, it is difficult to maintain its mechanical properties after melt extrusion. [17][18][19][20][21][22][23] In this research, recycled PET was extruded at a temperature lower than cold-crystallization temperature of PET (T c ) at prezone and close to the melting temperature of PET (T m ) at die. Materials were crushed, plasticized, and blended by the shear force of screws rotating.…”

“…Extrusion process was successfully conducted, and the degradation of PET was improved. [17][18][19] In this research, maleic anhydride grafted linear low-density polyethylene (LLDPE-g-MA) was used to modify recycled PET beverage bottles by low-temperature solid-state extrusion. The effects of the LLDPE-g-MA content on mechanical properties, thermal properties, and morphology have been investigated systematically.…”

“…The hydrolytic degradation and thermal degradation of PET result in poor mechanical properties. For recycled PET, it is difficult to maintain its mechanical properties after melt extrusion 17–23. In this research, recycled PET was extruded at a temperature lower than cold‐crystallization temperature of PET ( T c ) at prezone and close to the melting temperature of PET ( T m ) at die.…”

Effect of modified carbon black on the UV/IR screening ability of poly(ethylene terephthalate) transparent films

“…Poly(ethylene terephthalate) (PET) is a semicrystalline polymer with high performance and low cost, which is widely used in many areas including fibers, films, bottles for beverage and engineering components [3]. To satisfy the requirement of transparent window membrane, it is necessary for PET to be mixed with some certain particular photo stabilizers.…”