Synthesis Of PMMA/SiO₂ Hybrid Materials And Its Modification Of Polyolefin

Poly(methyl methacrylate)/silica hybrid materials were synthesised by three methods with precursor of silicate. The three methods were direct dispersion in solution, introducing hydroxypropyl methy methacrylate(HPMA) as active monomer and introducing 3-(trimethyloxysilyl)propyl methacrylate(MPTMS) as active monomer. The hybrid materials were also used to modify PP and HDPE as fillings.The phenomena of phase separation were avoided in hybrid material at the presence of HPMA. The result hybrid material was powdery and the glass transition temperature (Tg) was over 210. The hybrid material was organic-inorganic crosslinkage macromolecules within the dimensions of colloid at the presence of MPTMS. There were covalence bonds between organic and inorganic phases in the result hybrid material and Tg was about 125.The impact strength of PP two-element composites and three-element composites was improved. When the content of hybrid material in PP hybrid composites was lwt%, impact strength increased by 14% and 40%.respectively. The structure of PP hybrid composites was analyzed through polari-microscope and SEM.The hybrid material exhibitted selectivity in the modification of HDPE. The hybrid material had reinforcing and toughening effects on the lower crystallization HDPE such as HDPE5000S.At the filling rate 0.5%, tensile strength was improved by 8% and impact strength was improved by 20 percents.respectively. The configuration of fractured surface was analyzed by SEM.