Thermal properties of α,ա- aminoalkylterephthalamides prepared from waste poly(ethyleneterephthalate) bottle and aliphatic diamines

Trimers and pentamers of α,ա- aminoalkylterephthalamides were prepared from aminolysis of waste poly(ethyleneterephthalate) (PET) bottle with tetramethylene diamine (TMDA) and hexamethylene diamine (HMDA). The thermal properties of these products determined by DSC and TG showed that the melting points were the temperatures at which physical melting process and chemical transamidation polymerization occured concurrently. This chemical reaction had converted trimers and pentamers into polymers, then at the higher temperature ranges, the observed decomposition temperatures were just specific for newly formed polyamides, not for initial trimers or pentamers. The application of thermogravimetric chamber as mini reactor is quite useful to investigate the heating conditions for solid-state polymerization of α,ա- aminoalkylterephthalamides.