乳液法环氧化改性天然杜仲胶  

Epoxidation Modification of Nature Eucommia Ulmoides Gum by Emulsion Process

作　　者：杨凤[1] 王芳[1] 方庆红[1] 刘奇[1] 

机构地区：[1]沈阳化工大学材料科学与工程学院,辽宁沈阳110142

出　　处：《高分子材料科学与工程》2015年第5期56-61,共6页Polymer Materials Science & Engineering

基　　金：国家自然科学基金资助项目(51203092)

摘　　要：天然杜仲胶(EUG)分子链中含有亲水性的酯基,利用这一特点,采用乳液法制备了环氧化改性杜仲胶(EEUG)。通过差示扫描量热法和核磁共振等手段对EEUG进行了表征;讨论了固含量对乳液体系的稳定性和环氧化反应的影响,并对环氧度对产物的熔融-结晶行为和对硫化胶的拉伸性能、硬度及耐油性的影响进行了分析。结果表明,环氧度对环氧化产物的结晶和力学性能影响显著。随环氧度增加,产物结晶度逐渐降低,环氧度为25.4%时完全失去结晶能力;随环氧度增加,硫化胶的拉伸强度和硬度均下降,但是断裂伸长率明显增加,由硬质结晶材料转变为软而韧的弹性体。环氧化杜仲胶硫化胶的耐油性明显优于纯杜仲胶。In this article,emulsion process was used to epoxidize Eucommia ulmoides gum based on the fact that molecular chains of Eucommia ulmoides gum( EUG) are ended with hydrophilic ester groups,which imparts EUG with some water-solubility. The obtained epoxidized Eucommia ulmoides gum( EEUG) was characterized by differential scanning calorimetry( DSC) and nuclear magnetic resonance(1H-NMR). The influence of solid contents on the stability of the emulsion and epoxidation reaction was discussed. Also,the effect of epoxy contents on the thermal behavior of the epoxidized products,and on the hardness,tensile properties and oil resistance of the vulcanizate was analyzed mainly.The results show that crystallization and mechanical performance of the EEUG are closely related with its epoxy contents.With epoxy contents increasing,the crystallinity degree of EEUG decreases gradually,and the one with the epoxy content of 25. 4% completely loses its crystallization ability. Tensile strength and hardness of vulcanized EEUG decrease with epoxy contents increasing,while elongation at break increases significantly,suggesting the transformation of EUG from hard and crystalline materials into soft and tough elastomer. Oil resistance of EUG vulcanizate is greatly improved by epoxidation modification.

关 键 词：杜仲胶 环氧化 乳液法 

分 类 号：TQ332.2[化学工程—橡胶工业]