Preparation, Properties And Characterization Of HNBR Composites

Raw rubber and compounding system are important factors affecting rubber performance. Suitable raw rubber and its compounding system can make rubber show excellent performance. In this thesis, effects of raw rubbers and their compounding system on properties of HNBR composites investigated by advanced analysis test methods.The first part, the influence of raw rubbers on properties of HNBR composites was studied.The results indicated that the glass-transition temperature enhanced with an increase in the acrylonitrile content and hydrogenation and the crosslinking density rised with increase of the acrylonitrile and double bond content. High unsaturated HNBR showed low break elongation and tear strength and higher stress at100%, and tensile strength was improved little. With an increase in crylonitrile content, both tensile strength and tear strength improved and stress at100%increased, however, break elongation had little change. NBR/HNBR blends have low break elongation, mechanical properties and aging resistance, while the vulcanization rate accelerate.The second part, the influence of active agent and plasticizer on properties of HNBR composites was studied. The results indicated that compared with ordinary zinc oxide, active zinc oxide can entrust the rubber more excellent mechanical properties, aging resistance performance and heat resistance. Aging resistance performance of HNBR composites plasticized by HTBN decreased. When the amount of plasticizer HTBN was3phr, aging resistance and tensile strength improved. Plastification, crosslinking and reinforcement were mainly effects of coumarone on HNBR.With an increase in coumarone contents, elongation at break and mooney viscosity increased. Glass-transition temperature and storage modulus of composites filled coumarone increased.The vulcanizate had the biggest tensile strength and stress at100%, the lowest loss factor(tanδ) when coumarone content of compsites was5phr, The tearing strength was79.1kN/m when coumarone content of composites was7.5phr. The third part, the influence of different reinforcers such as carbon black,OMMT or HZMMA on properties of HNBR composites was studied. The results indicated that vulcanization rate of composites accelerated if N401was partly replaced by OMMT, however tensile strength and break elongation improved little. HZMMA can significantly improve the vulcanization rate and mechanical properties. HNBR composites filled with N220and HZMMA showed super mechanical properties at high temperature. It was found that homopolymerization of HZMMA occurred in vulcanization process, and the ionic bond formed, which had good reinforcing effect on rubber.The forth part,the effect of DCP on HNBR composites was studied. Crosslink densities of HNBR vulcanizates were measured by pulsed nuclear magnetic resonance(NMR). The influence of DCP contents on mechanical properties, thermal performance and damping property of rubber were researched. The results indicated that with an increase in content of DCP, vulcanizates had resulted in an increase in Tg, E’and crosslink density, an improvement of the resistance, an decrease in tan5, and there was a maximum in tensile strength. At the same time, area of loss temperature broadened.