Reinforced unsaturated polyester composites by chemically grafting amino-POSS onto carbon fibers with active double spiral structural spiralphosphodicholor

The grafting of amino-POSS on the carbon fibers (CFs) surface was achieved through the reaction of the spiralphosphodicholor (SPDPC) grafted on the CFs surface with aminopropylphenyl polyhedral oligomeric silsesquioxane (amino-POSS). X-ray photoelectron spectroscopy (XPS) showed that the phosphorus, chlorine and silicon containing functional groups were obviously increased after the modifications. Both CFs grafted with SPDPC and CFs grafted with SPDPC plus amino-POSS have been used to prepare unsaturated polyester resin (UPR) composites. The grated SPDPC and grafted with a combined SPDPC and amino-POSS improved the interfacial performance of the CFs/UPR composites, respectively. Atomic force microscopy (AFM) results showed that the surface roughness of the CFs grafted with SPDPC was lower than that of the CFs grafted with a combined SPDPC and amino-POSS. Dynamic contact angle analysis of the CFs grafted with SPDPC showed higher wettability to UPR than that of the CFs grafted with a combined SPDPC and amino-POSS. Force modulation atomic force microscopy (FMAFM) and interlaminar shear strength (ILSS) were used to characterize the interfacial properties of the composites. After grafted with a combined SPDPC and amino-POSS, the ILSS of the composites was increased by 22.9% due to the well interfacial properties that were caused by the improvement of CFs surface roughness.