国产溶聚丁苯橡胶T2000 R的微观结构及基本性能

采用傅里叶变换红外光谱分析、凝胶渗透色谱-激光光散射-自动黏度在线检测仪、动态力学性能分析及差示扫描量热仪等手段对国产溶聚丁苯橡胶(SSBR-T2000 R)的微观结构及其基本性能进行了分析与表征,并与乳聚丁苯橡胶(ESBR-1502)作了对比。结果表明,与ESBR-1502相比,SSBR-T2000 R具有分子量分布窄、数均分子量较高、重均分子量明显低、支化度低的特点;其链结构中顺式-1,4-结构含量高、反式-1,4-结构、1,2-结构含量低;热稳定性高于ESBR-1502;玻璃化转变温度比ESBR-1502低,说明其具有优异的低温性能;高弹态动态模量较低,但其动态损耗因子和动态生热低于ESBR-1502;其硫化特性为焦烧时间较长,而正硫化时间较短;用密炼机加工胶料,SSBR-T2000 R的耐屈挠龟裂性优于ESBR-1502,且压缩生热较低。

Microstructure and basic properties of domestic solution-polymerized styrene-butadiene rubber T 2000 R

The characterization of microstructure and basic properties of domestic solution-polymerized styrene-butadiene rubber (SSBR-T 2000 R) was carried out by different means, such as Fourier transform infrared spectroscopy, gel permeation chromatography-laser light scattering-automatic online viscosity detector, dynamic mechanical analysis and differential scanning calorimeter, and the comparison with emulsion styrene-butadiene rubber (ESBR-1502) was made. The results showed that SSBR-T 2000 R had a narrower molecular mass distribution, higher number-average molecular mass, significantly lower weight-average molecular mass and lower branching degree compared with ESBR-1502. Its cis-1,4-unit content was higher, while trans-1,4-unit and 1,2-unit content lower than those of ESBR-1502. Its thermal stability was higher than ESBR-1502. Its glass transition temperature was lower than ESBR-1502 which indicated that it had a better low temperature property. Under dynamic application, SSBR-T 2000 R had lower dynamic modulus, loss factor and dynamic heat build-up than ESBR-1502. For cure characteristics, SSBR-T 2000 R had a longer scorch time and shorter optimal curing time than ESBR-1502. SSBR-T 2000 R vulcanizates showed better flex-crack resistance and lower compression heat build-up than ESBR-1502 when compounds mixed by internal mixer.