Interpolymers of PA-6 and PET were synthesized in the presence of oligocarbodiimides having a degree of polymerisation of 5 and 20. The synthesis was carried out by blending PA-6 with PET in the melt at 280°C. IR-spectroscopy and selective extraction experiments demonstrated the main features of the chemical structure of the reaction products, which can be considered as interpolymer concentrates. A significant increase in Charpy impact strength occurred when at least 2 parts per hundred by weight of interpolymer concentrate was introduced into a PA-6/PET polyblend.
