Study On The Preparation And Properties Of PET/Inorganic Powder Composites

In thise paper three kinds of inoganic powder modified CaO-A,unmodified CaO-B and precipitated CaCO₃ were added into the esterification stages of PET synthesis.The influence of the different powders,different concents,and ultrasonic pretreatment on the in-situ polymerization of PET/CaO-A,PET/CaO-B and PET/CaCO₃ composites and the performance of the composites has been studied.The esterification kinetics results showed that in low and the same adding amount of different powders,CaCO₃ and CaO-A promoted the esterification.For CaO-A,the increase of adding amount could slow down the esterification,and increase the activation energy of esterification.Treating with coupling agent the amount of CaO-A could be increased and the esterification activation energy could be decreased in a certain extent.DSC,TG,WAXD,SEM,IR,capillary rheometer,tensile testing machine was used to test and characterize the obtained PET composites.The results showed that in the same dosage,CaO-A was obviously enlarged crystallization temperature range,the T_mc was increased,T_ccdecreased.The thermal stability of PET/CaO-A is better than PET/CaO-B and PET/CaCO₃.With the increase of CaO-A content,the crystallization temperature range of PET/CaO-A composites tends to increase,and the crystallinity of PET/CaO-A composites increases.SEM showed that CaO-A has been dispersed well in the matrix.The rheological results showed that the composites were all pseuoplastic fluids.The non-isothermal crystallization kinetics of pure PET and PET/CaO-A composites were studied by Jeziorny,Ozawa,and Mo.The results showed that PET/CaO-A was accord with Mo's equation.CaO-A improved the crystallization rate of the PET/CaO-A composite.With the increase of CaO-A,the crystallization rate and the crystallinity both increased.For the same composites,with the increase of DSC cooling rate the rate of crystallization increased and the crystallinity decreased.The tensile test showed that PET/CaO-A composites had higher tensile strength and elongation at breakage.