几种低粘度恒粘天然橡胶的性能研究

Properties of Different Constant Viscosity NR with Low Viscosity

采用盐酸羟胺、硫酸羟胺、盐酸氨基脲和促进剂M作为恒粘剂分别制备了天然橡胶(NR)-HH,NR-HS,NR-SH和NR-MB低粘度恒粘NR,并研究NR的理化性质、贮存性能、硫化特性和物理性能。结果表明:与未采用恒粘剂的NR-CK相比,4种恒粘NR的塑性初值稍小,NR-MB的塑性保持率明显降低;NR-MB胶料的硫化速度大于NR-CK胶料,NR-HS,NR-HH和NR-SH胶料的硫化速度则小于NR-CK胶料;NR-HH,NR-HS和NR-SH硫化胶的拉伸强度和撕裂强度相当,均低于NR-CK硫化胶,而NR-MB硫化胶的拉伸强度和撕裂强则高于NR-CK硫化胶。几种恒粘剂均能有效降低NR的门尼粘度,改善其耐热空气老化性能,其中盐酸羟胺和硫酸羟胺对NR的恒粘效果较好。

Several kinds of constant viscosity natural rubber(NR) with low viscosity(NR-HH,NR-HS, NR-SH and NR-MB) were prepared with hydroxylamine hydrochloride,hydroxylammonium sulphate, semicarbazide hydrochloride and accelerator M as viscosity stabilizer,respectively,and their physicochemical properties,storage performance,curing behavior and physical properties were studied. The results showed that,P0 values of NR-HH,NR-HS,NR-SH and NR-MB were lower than that of NR-CK,and PRI of NRMB was significantly lower compared with that of NR-CK. The curing rate of NR-MB compound was faster than that of NR-CK compound,and the curing rates of NR-HS,NR-HH and NR-SH compound were slower than that of NR-CK compound. The tensile strength and tear strength of NR-HH,NR-HS and NRSH vulcanizates were equivalent and all worse than those of NR-CK vulcanizate,but the tensile strength and tear strength of NR-MB vulcanizate were higher than those of NR-CK vulcanizate,respectively. All these viscosity stabilizers could effectively decrease the Mooney viscosity of NR and improve the hot air aging resistance. Among them,hydroxylamine hydrochloride and hydroxylammonium sulphate showed a better effect on the stabilization of NR viscosity.