Abstract: Using benzoyl peroxide (BPO) as an initiator, vinyl silane was grafted onto nature rubber via melt-blend forming NR-g-silane, which could be further treated via hot water crosslinking. The grafted rubbers were characterized using Fourier transform infrared spectroscopy (FTIR) and scanning electric microscopy (SEM). The effects of contents of silane and BPO, grafting and crosslinking conditions (time and temperature) on the gel content of crosslinked NR-g-silane were studied in this article. At the same time, the relationship between the gel content and mechanical property of the crosslinked NR-g-silane was also explored. With increasing contents of silane and BPO, blending time and temperature, crosslinking time and temperature, the gel content of the crosslinked NR-g-silane increased monotonously. With increasing gel content, an obvious improvement in mechanical property was observed. Compared with raw nature rubber, tensile strength and elongation at break of the crosslinked silane grafted nature rubber (80wt% gel) were improved by 30 % and 8.5 times, respectively.

Key words: grafing, natural rubber, silane, crosslinking in hot water