Effect of copolymers synthesized by nitroxide‐mediated polymerization as chain extenders of postconsumer poly(ethylene terephthalate) waste

In this contribution, the use of glycidyl methacrylate and styrene copolymers synthesized by nitroxide‐mediated polymerization (NMP) as chain extenders of postconsumer poly(ethylene terephthalate) waste (r‐PET) is described. Our observations revealed that the copolymers synthesized by NMP act as efficient chain extenders for the regeneration of PET waste. Epoxide groups in the copolymers react with PET end reactive groups producing chain extended PET with higher molecular weight and improving performance. The increase in molecular weight of PET waste results in important improvement in both, elongation‐at‐break, and strength impact. r‐PET complex viscosity and rheological moduli are also greatly improved as the epoxide content in the chain extenders increases. The loss tangent and phase angle versus angular frequency plots for chain‐extended r‐PET reveal that melt elasticity is also improved. These results confirm that use of NMP‐synthesized copolymers is a plausible solution for the recycling of PET. POLYM. ENG. SCI., 59:2255–2264, 2019. © 2019 Society of Plastics Engineers