Fast Functionalisation of Polypropylene (Pp) by Ultraviolet Irradiation and Compatibilised Pp/Caco ₃ Composite

Some oxygen-containing groups such as C–O and C=O were quickly introduced onto polypropylene (PP) chains by ultraviolet irradiation at high light intensity and high environmental temperature in air. The content of the groups increased with increasing time of ultraviolet irradiation. There was no gel in ultraviolet-irradiated PP. Compared with those of unirradiated PP, the crystal form and the phase space of ultraviolet-irradiated PP did not change, but its melt temperature decreased, and its crystallinity, liquidity and hydrophilicity increased. The ultraviolet-irradiated PP used as compatibiliser was melt blended with PP and CaCO ₃ , and a PP/irradiated PP/CaCO ₃ composite was prepared. Compared with those of PP/CaCO ₃ composite, the compatibility and dispersion of the PP/irradiated PP/CaCO ₃ composite were improved, and its tensile strength and notched impact strength were increased.