Studies On Up-montmorillonite Nanocomposites

Polymer/montmorillonite nanocomposites is a kind of novel composites due to the excellent properties as well as their wide applications in the future. The aims of this study on unsaturated polyester (UP)/montmorillonite nanocomposites are to improve the properties and to provide valuable instructions for thermosetting resin systems.In this thesis, the blends of different organic amines or ammonium and unsaturated organic amine were used to modified montmorillonite to prepare organic montmorillonite.UP/montmorillonite nanocomposites was prepared by in situ intercalation polymerization. Its microstructure was characterized by TGA, XRD and TEM. The results show that the UP/montmorillonite nanocomposites is intercalated nanocomposites.The mechanical properties, thermal properties and wear properties were studied in this thesis. Compared to pure UP, the tensile strength and impact strength of nanocomposites with about lwt% organic montmorillonite increase by 20% and 100%, respectively. These results show that the nanocomposites is toughened and strengthened. The thermal stability of nanocomposites is improved and when organic montmorillonite content is lwt%, heating distortion temperature (HDT) of nanocomposites increases by 17.6癈 from 75.8癈 to 97.4癈. The wear loss of nanocomposites with 2wt% organic montmorillonite content is 1/10 of pure UP's. The SEM photos show the wear mechanisms of pure UP are fatigue detachment and light cut form, but wear mechanisms of nanocomposites are abrasive filler wear and adhesion wear.The FT-IR results show organic montmorillonite has inhibition to the curing reaction of unsaturated polyester. The curing kinetics parameters of UP with lwt% organicmontmorillonite were determined by the dynamic DSC. Its apparent activation energy is higher than pure UP's, but reaction order is similar. These results show the addition of organic montmorillonite increase difficulty degree of curing reaction.The thermal decompostion kinetics of UP/montmorillonite nanocomposites under nitrogen was studied. The reaction order and apparent activation energy of nanocomposites were obtained by Freeman-Carroll method. The results indicate the thermal stability of nanocomposites is higher than pure UP's.