不同地域天然橡胶的结构与性能对比

Comparison of Structure and Properties of Natural Rubber from Different Regions

以4种不同地域天然橡胶为目标样品,利用DSC、FT-IR和ARES流变仪等分析手段,分析了目标样品微观结构与结晶性能差异。结果表明,4种天然橡胶的零切粘度(η0)大小顺序为SIR>SMR>STR>SCR,其相对分子质量大小顺序为SIR>SMR>STR>SCR。4种不同地域天然橡胶分子链具有不同的CH3/CH2基团数量,相应的3,4异构体含量大小顺序为STR>SIR>SMR>SCR。4种天然橡胶在-25℃下等温结晶后的熔融曲线呈现明显的双峰结构,具有α和β2种晶型结构,结晶度大小顺序为SMR>SIR>SCR>STR,结晶速度大小顺序为SIR>SMR>SCR>STR,自补强性能大小顺序为SCR>SMR>SIR>STR,SMR和SCR的玻璃化转变温度高于SIR和STR。

4 kinds of NR from different regions were used as target samples,the differences of microstructure and crystallization properties of the target samples were analyzed by using DSC,FT-IR and ARES technology.The results showed that the order of zero tangent viscosity of the 4 kinds of NR was SIR>SMR>STR>SCR,the order of the molecular mass was SIR>SMR>STR>SCR.The molecular chains of the 4 kinds of natural rubber from different regions had different number of CH3/CH2 groups,the order of the 3,4 isomers content was STR>SIRS>MR>SCR.The melt curves of the4 kinds of natural rubber had obvious two peak structure after constant temperature crystallization at-25℃ withαandβcrystalline,the order of the crystallinity was SMR>SIR>SCR>STR,the order of crystallization rate was SIR>SMR>SCR>STR,the order of the self reinforcement was SCR>SMR>SIR>STR.The glass transition temperature of SMR and SCR was higher than that of SIR and STR.