Natural rubber(NR)grafted with 2-ethylhexyl acrylate(2-EHA)and methacrylic acid(MAA,collectively NR-g-PEHA/MAA)was synthesized by emulsion polymerization.Tetraethylenepentamine and cumene hydroperoxide were used as re...Natural rubber(NR)grafted with 2-ethylhexyl acrylate(2-EHA)and methacrylic acid(MAA,collectively NR-g-PEHA/MAA)was synthesized by emulsion polymerization.Tetraethylenepentamine and cumene hydroperoxide were used as redox initiators.The successful grafting of 2-EHA and MAA onto NR was confirmed by Fourier transform infrared spectroscopy.The morphology of the NR latex particles was observed by transmission electron microscopy.The effects of reaction temperature,initiator dosage,feeding mode,and hard monomer content on the mechanical properties of the modified NR film were investigated.Grafted polymer chains were unevenly wrapped on the outside of NR particles,and smaller particles were more easily grafted.Crosslinking was characterized using a toluene swelling method.Thermal stability and glass transition temperature were examined by differential scanning calorimetry and thermogravimetric analysis.The results showed that the thermal stability of NR-g-PEHA/MAA had been improved,and the glass transition temperature(Tg)was unchanged.展开更多
通过熔体流动速率、热变形温度和力学性能等指标变化评价了ASA胶含量及用量对PC/ASA合金性能的影响。结果表明,随着ASA用量的增加,合金的热变形温度下降;可以通过ASA胶含量和用量调节合金的流动性;不论合金的组成,ASA胶含量为30%的PC/AS...通过熔体流动速率、热变形温度和力学性能等指标变化评价了ASA胶含量及用量对PC/ASA合金性能的影响。结果表明,随着ASA用量的增加,合金的热变形温度下降;可以通过ASA胶含量和用量调节合金的流动性;不论合金的组成,ASA胶含量为30%的PC/ASA合金的低温冲击强度最高;当PC/ASA比例为7∶3,ASA胶含量为30%时,PC/ASA合金的低温冲击强度最高为36 k J/m^(2)。展开更多
文摘Natural rubber(NR)grafted with 2-ethylhexyl acrylate(2-EHA)and methacrylic acid(MAA,collectively NR-g-PEHA/MAA)was synthesized by emulsion polymerization.Tetraethylenepentamine and cumene hydroperoxide were used as redox initiators.The successful grafting of 2-EHA and MAA onto NR was confirmed by Fourier transform infrared spectroscopy.The morphology of the NR latex particles was observed by transmission electron microscopy.The effects of reaction temperature,initiator dosage,feeding mode,and hard monomer content on the mechanical properties of the modified NR film were investigated.Grafted polymer chains were unevenly wrapped on the outside of NR particles,and smaller particles were more easily grafted.Crosslinking was characterized using a toluene swelling method.Thermal stability and glass transition temperature were examined by differential scanning calorimetry and thermogravimetric analysis.The results showed that the thermal stability of NR-g-PEHA/MAA had been improved,and the glass transition temperature(Tg)was unchanged.
文摘通过熔体流动速率、热变形温度和力学性能等指标变化评价了ASA胶含量及用量对PC/ASA合金性能的影响。结果表明,随着ASA用量的增加,合金的热变形温度下降;可以通过ASA胶含量和用量调节合金的流动性;不论合金的组成,ASA胶含量为30%的PC/ASA合金的低温冲击强度最高;当PC/ASA比例为7∶3,ASA胶含量为30%时,PC/ASA合金的低温冲击强度最高为36 k J/m^(2)。
