交联密度对丁苯橡胶与溶剂Flory-Huggins相互作用参数的影响

Influence of Crosslinking Density on Flory-Huggins Interaction Parameter between SBR and Solvent

研究丁苯橡胶(SBR)的交联密度对SBR与溶剂Flory-Huggins相互作用参数的影响。改变硫黄用量制备了不同交联密度的SBR试样,并采用管道模型计算出交联点间平均相对分子质量,结合平衡溶胀法测得SBR在甲苯、环己烷和乙酸乙酯中溶胀后的体积分数,使用Flory-Rehner方程得到SBR与溶剂的相互作用参数。结果表明:SBR与溶剂的相互作用参数与SBR的体积分数呈线性关系,但溶剂不同,关系式不同。对平衡溶胀法测定交联点的平均相对分子质量的Flory-Rehner方程提出了一个修正式。

The influence of the crosslinking density on the Flory-Huggins parameter between SBR and solvent was studied. The samples with different crosslinking density were prepared by changing the addition level of sulfur. The average molecular weight between crosslinking points was calculated using Tube model.The volume fractions of rubber after swelling in toluene,cyclohexane and ethyl acetate were measured by equilibrium swelling test. Then the interaction parameters between rubber and solvents were obtained using Flory-Rehner equation. The results showed that the interaction parameter had a linear relationship with the volume fraction of rubber after swelling. However,the relationship was different for different solvents. In this study,a modified Flory-Rehner equation was also proposed to calculate the average molecular weight between crosslinking points by the equilibrium swelling method.