CAJ | 학술논문

采用溶液法对杜仲橡胶(EUG)进行环氧化改性,考察反应条件对环氧化反应的影响,采用红外光谱法、核磁共振氢谱法和差示扫描量热法等研究环氧度(E)对环氧化EUG(EEUG)熔融-结晶行为的影响.结果表明:随着反应温度升高和甲酸用量增大,E逐渐增大;反应温度为50 ℃,n(甲酸)︰n(碳-碳双键)︰n(双氧水)=0.8︰1︰1时,E较大,无明显的副反应;环氧化反应未改变橡胶分子链构型,EEUG的分子链仍然是反式-1,4结构;随着E增大,EEUG的结晶能力减弱,E为24.8%时EEUG完全失去结晶能力,宏观上由室温下的硬质塑料转变为弹性体.
채용용액법대두중상효(EUG)진행배양화개성,고찰반응조건대배양화반응적영향,채용홍외광보법、핵자공진경보법화차시소묘량열법등연구배양도(E)대배양화EUG(EEUG)용융-결정행위적영향.결과표명:수착반응온도승고화갑산용량증대,E축점증대;반응온도위50 ℃,n(갑산)︰n(탄-탄쌍건)︰n(쌍양수)=0.8︰1︰1시,E교대,무명현적부반응;배양화반응미개변상효분자련구형,EEUG적분자련잉연시반식-1,4결구;수착E증대,EEUG적결정능력감약,E위24.8%시EEUG완전실거결정능력,굉관상유실온하적경질소료전변위탄성체.
In this study, eucommia ulmoides gum (EUG) was modiifed by epoxidation in solution. The effect of reaction conditions on the epoxidation reaction was investigated. The inlfuence of epoxidation content (E) on the melting and crystallization characteristics of epoxidized eucommia ulmoides gum (EEUG) was studied using infrared spectroscopy, nuclear magnetic resonance spectroscopy and differential scanning calorimetry methods. The experimental results showed that, when the reaction temperature increased and the amount of formic acid increased, the epoxidation content of EEUG increased. When the reaction temperature was 50 ?C, the ratio ofn (formic acid)︰n (double bond)︰n (hydrogen peroxide) was 0.8︰1︰1, the resulted epoxidation content of EEUG was high and there was no signiifcant side reaction. It was found that the epoxidation reaction did not change the rubber molecular chain conformation, while the molecular chain of EEUG remained trans-1,4 structure. With the increase of epoxidation content, the crystallinity of EEUG decreased, and EEUG became an elastomer when the epoxidation content reached 24.8%.