摘要
用 DSC,TGA,WAXD和 SEM研究了溶液浇注制备马来酸酐封端的聚亚丙基碳酸酯 /乙基纤维素共混物 (MAPPC/EC)的相容性、热稳定性、聚集态结构和形态。共混物存在单一玻璃化温度揭示 MAPPC和EC在非晶区相容。富 EC共混物的固相 -液晶相转变温度和液晶相 -各向同性态转变温度和转变焓均随 EC含量增加而增加。在 MAPPC中混入 EC,热分解温度提高 ,特别是质量比为 90∶ 1 0的 MAPPC/EC共混物热分解温度增加在富 MAPPC共混物中最明显。在胆甾型液晶 EC中混入 MAPPC,EC的 2个峰向大 Bragg角方向移动 ,使介晶相聚合物层间距及链间距变小 ;结晶相微晶尺寸增大 ,非晶相尺寸减小 ,共混物堆砌更紧密。
Blends of maleic anhydride endcapped poly(propylene carbonate)(MAPPC) with ethylcellulose(EC) in different mass fraction composition were prepared by solution casting. DSC, TGA, WAXD and SEM were used to investigate the miscibility, thermal stability, aggregation structure and morphology of the blends. A single glass transition temperature of the blend revealed the miscibility of MAPPC with EC in the noncrystalline region. The solid phase-mesophase phase transition temperature, the mesophase-isotropic phase transition temperature and the transition enthalpy of the blends were found increased gradually with the increase of EC content in the EC-rich blend. Upon blending EC into MAPPC, the thermal decomposition temperatures were elevated, especially for MAPPC/EC blend with mass ratio of 90∶10. Dilution of MAPPC with cholesteric liquid crystalline EC caused the shift of two peaks of EC to greater Bragg angles and the decrease of the distances between layers of ordered polymer chains and the distances between polymer chains, and resulted in the increase of crystallite dimensions of mesophase region and the decrease of sizes of non-crystalline region. Blends appeared to pack more compactly.
出处
《应用化学》
CAS
CSCD
北大核心
2002年第11期1027-1031,共5页
Chinese Journal of Applied Chemistry
基金
国家重点基础研究专项经费资助 (G19990 64 80 0 )
中国科学院重大项目基金 (KJCX2 -2 0 6A-0 3 )
