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The influence of accelerator M and accelerator NS on dynamic properties of NR vulcanizate was investigated by using rubber processing analyzer (RPA), flexometer and Nuclear Magnetism Resonance (NMR). The results showed that the degree of crosslinking density of NR vulcanizate by using accelerator NS was higher than NR vulcanizate by using accelerator M, the response of dynamic properties of vulcanizate to frequency and temperature was different, and the NR vulcanizate cured with accelerator NS had lower heat built up than NR vulcanizate cured with accelerator M.

Surface modified nanocrystalline cellulose (NCC) was prepared by silicon-69, and then blended into natural rubber latex to prepare nanocomposites. The nanocomposites properties of tensile properties, tear strength, morphology and thermal dynamic mechanical properties were measured by mechanical property testing, scanning electron microscopy (SEM), and dynamic mechanical analysis (DMA), respectively. The results showed that modified NCC is homogeneously distributed throughout NR matrix, which leads to the enhancement on mechanical properties. Moreover, the storage modulus (E) of modified nanocellulose filled NR is higher than unmodified nanocellulose filled NR, and the tanδ is reversed.

Pineapple leaf fiber (PALF) was pretreated by sodium hydroxide, and hydrolyzed by sulfuric acid to obtained nano-cellulose (NC). The SEM showed that size of NC is 30-50nm. Bis[3-(triethoxysilyl)propyl]tetrasulfide (Si-69) was employed to sueface modificate the NC. The results of characterization of particle size, zeta potential, FTIR and contact angle illuminated that particle size of surface modified NC was smaller than NC and zeta potential of -75.8mV was lower than NC’s. The hydrophobicity of surface modifiedNC has been improved.

Test of the rheology behavior for low protein natural rubber(LPNR) were carried out with rubber processing analyzer(RPA), and molecular weight were carried out with gel permeation chromatography(GPC). The results showed that molecular of LPNR is lower than natural rubber(NR), The complex viscosity(n*) of NR is higher than LPNR. The stress relaxation indicate that time of LPNR is faster than NR, it illuminate that LPNR has lower molecular weight than NR, and processing performance have distinct discrepancy between NR and LPNR. The torque(S’) with strain rising indicated that one linear viscoelastic region and one nonlinear viscoelastic region in whole range, and LPNR has lower S’ than NR.