Fabrication and characterization of nanocomposites with high-impact polystyrene and hydroxyapatite with well-defined polystyrene via ATRP

An efficient technique for the SI-ATRP of PS at the HAP surfaces was achieved through immobilization of the macroinitiator (BIBB). FTIR, TGA, NMR, and TEM studies confirmed that the modified individual nanoparticles composed of a HAP core and well-defined, densely grafted outer PS, which demonstrated that the surface of HAP was grafted with polymer chains successfully. Then, HAP/HIPS nanocomposites with different loadings of pristine HAP and modified HAP were prepared by solution mixing. The mechanical properties of the nanocomposites increased remarkably by introducing surface-coated nanoparticles due to the strong interfacial interaction and good compatibility between the two components, which was further confirmed by the SEM images of the brittle fracture face of the nanocomposites. Compared with the corresponding HIPS samples, DSC results demonstrated that the HAP/HIPS nanocomposites exhibited higher glass transition temperature (T_g).