METHOD OF MODIFYING SURFACE OF POLYETHYLENE TEREPHTHALATE GRANULATE Russian patent published in 2013 - IPC C08G63/91 C08G63/88 C08G63/183 C08J7/12 C08F8/00 

FIELD: chemistry.

SUBSTANCE: present invention relates to a method of modifying the surface of a polyethylene terephthalate granulate in order to increase heat-, light-, wear- and hydrolytic resistance, as well as reduce gas permeability of polymer materials. The method involves treating the surface of a polyethylene terephthalate granulate with a modifier while heating. The modifier used is a mixture of fluorine-containing prepolymers in amount of 2 pts.wt per 100 pts.wt polyethylene terephthalate in weight ratio of 83(I):12(II+III):5(IV), represented by formulae (I)-(IV) in the claim. Said compounds are obtained in advance by reacting 4,4'-diphenylmethane diisocyante with 1,1,5-trihydroperfluoropentanol-1 in the presence of catalytic amounts of di-n-butyltin dilaurate in molar ratio of 1:1:0.005, respectively, in a medium of chlorobenzene and n-hexane in volume ratio of 8:1, at temperature of 80°C, ultrasound frequency 40 kHz for 2 hours. Modification is carried out in a medium of chlorobenzene at 150°C for 4 hours.

EFFECT: method widens the operating temperature range of articles made from polyethylene terephthalate.

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