Metal catalysis to improve compatibility at PO/PET blends interfaces

Reactive blending of 70/30 by weight PET/polyolefin (PO) mixtures was carried out in a discontinuous mixer using a polyolefin functionalized with dialkyl maleates and potential transesterification catalysts to improve the formation of graft PO-PET copolymers. The yield of this reaction was evaluated by the analysis of FTIR spectra of blends residual fraction after selective extractions of unreacted polyester. The building of a calibration curve and the analysis of the spectra by deconvolution was performed to evaluate the percentage of grafted PET. The results are discussed in terms of influence of the different catalysts and of polyolefin structure on the blends morphology.