The graft polymerizations of stearyl methacrylate (SMA) and divinylbenzene (DVB) onto natural rubber (NR) were carried out in a solution process using benzoyl peroxide (BPO) as an initiator in toluene or chloroform. The main products of the grafted NR include an uncrosslinked (sol) part [sol(SMA–NR–DVB): s-SNRD] and a crosslinked (gel) part [gel(SMA–NR–DVB), g-SNRD]. s-SNRD was obtained by extraction using tetrahydrofuran. It was identified by IR and 1H-NMR spectroscopies. The glass transition temperature (Tg) and thermal properties of s-SNRD and g-SNRD were studied by DSC and TGA. The glass transition temperature and thermal decomposition temperature of s-SNRD and g-SNRD were higher than were those of NR. The light resistance and weatherability of s-SNRD were measured with a Weather-o-Meter. The light resistance and weatherability of s-SNRD are better than are those of NR. The effects of the initiator concentration, mol ratio of SMA to DVB, reaction time, temperature on grafting ratio, and crosslinking ratio were investigated. The highest grafting ratio and crosslinking ratio in the graft polymerization of SMA and DVB onto NR were obtained when the mol ratio of SMA to DVB and BPO were 4.0 and 2 wt %, at 80°C for 48 h, respectively. Following several studies on oil-absorptive polymers in our laboratory,9 the oil absorptivity of g-SNRD was examined using crude oil. The oil absorptivity of g-SNRD was 600% when the immersion time was 10 min. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 79: 2464–2470, 2001
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