The Impact of Nano CaCO 3 Modified in situ with Methacrylic Acid on the Structure and Properties of Natural Rubber

Natural rubber (NR) was reinforced in situ with nano CaCO 3 that had been modified with methacrylic acid (MAA)(M-CaCO 3 ). The structures and properties of the resulting composites were studied using attenuated total reflection Fourier transform infrared spectroscopy(ATR-FTIR), scanning electron microscopy(SEM), and Mooney viscometer and mechanical tests. The results show that when NR is physically blended with CaCO 3 and MAA, (Ca2+)-( − OOC) is formed in situ. When dicumyl peroxide (DCP) is added, the (Ca 2+ )-( − OOC) self-homopolymerizes, and during the curing process poly-(Ca 2 +)-( − OOC) is formed and grafts to the molecular chains of the NR via carbon-carbon double bonds. The NR/M-CaCO 3 composites formed have close interfacial interaction and are well dispersed. Compared with the NR composites reinforced with unmodified nano CaCO 3 , the NR/M-CaCO 3 composites have very different cure characteristics, rheological behavior, and mechanical properties, and these characteristics and properties show a significant relationship with the loading of M-CaCO 3 .