【摘要】 目的通过乙酸、高氯酸、乙酸酐等对纳米纤维素(NCC)进行乙酰化改性,再通过溶液浇铸法制备聚乳酸/改性纳米纤维素复合材料(PLA/m NCC)。方法采用紫外可见分光光度计对PLA/m NCC进行透明性测试及透光率分析;采用FE-SEM电镜观察m NCC在复合材料中的形貌;采用动态热机械分析仪进行动态热力学分析。结果与m NCC相比,NCC在PLA基体中的分散性更好。当m NCC质量分数小于4%时,可较均匀地分散在聚乳酸基体中,但随着m NCC含量的增加,团聚现象明显;PLA/m NCC的储能模量随着m NCC含量的增加而提高,但是m NCC的加入对材料玻璃化转变温度的影响非常小。结论为改善PLA的加工性能提供一定的实验及理论依据。更多还原

【Abstract】 In this paper, cellulose nanocrystal(NCC) was acetylated modified by acetic acid, perchloric acid and acetic anhydride. Then polylactic acid/modified NCC(m NCC) composite materials were prepared by solution casting. The transparency and light transmittance of composite materials were studied through UV visible spectrophotometer. The morphology of m NCC in composite materials was observed by FE-SEM electron microscopy. Dynamic thermodynamic analysis was carried out by Dynamic Mechanical Analyzer. The results showed that compared to NCC, m NCC had better dispersion in PLA matrices when the content of m Ncc was less than 4%. The nano-particles tended to aggregate with further increase of m Ncc content. The storage modulus of composite materials was improved with the increasing m NCC content and the existence of m NCC nearly had no influence on glass transition temperature. This study provides certain experimental and theoretical reference for the improvement of the processing performance of PLA.更多还原