【摘要】 以离子液体1-丁基-3-甲基咪唑四氟硼酸盐（BMIMBF₄）为二醋酸纤维素（CDA）增塑剂,在抗氧剂1010和亚磷酸三苯酯（TPPi）存在时熔融挤出造粒制备纺丝切片,进而熔融纺丝制备二醋酸纤维。研究了熔融挤出温度对CDA分子量的影响,以及熔融纺丝前后CDA化学结构和热性能的变化;进一步研究了二醋酸纤维的形貌以及牵伸对二醋酸纤维力学性质与结晶度的影响。结果表明:熔融温度对CDA分子量影响较大,熔融挤出温度从170℃增加到200℃时,CDA分子量由6.0×10⁴g/mol降低至2.0×10⁴g/mol;CDA增塑熔融纺丝前后化学结构并未发生明显变化,但其玻璃化转变温度因热降解而有所下降;对切片熔融纺丝可以得到强度为1.06 cN/dtex的二醋酸纤维,其断裂强度随着牵伸倍数增加而增加,结晶度也随之增加。更多还原

【Abstract】 1-butyl-3-methylimidazolium terafluoroborate（ BMIMBF₄）,a type of ionic liquids,was applied as a plasticizer of cellulose diacetate（ CDA）. Resins were obtained from the plasticized CDA with pentaerythritol tetrakys 3-（ 3,5-ditert-butyl-4-hydroxyphenyl） propionate and triphenyl phospite as additives and CDA fibers were successfully prepared by melt spinning. The effects of melting extruder temperature on the molecular weight and chemical structure of CDA were studied. The results showed that the molecular weight dropped from 6. 0 × 10⁴ g/mol to 2. 0 × 10⁴ g/mol when melt extruded temperature rised from 170 ℃ to 200 ℃. The chemical structure of CDA remained the same after melt spinning,but the glass transmission temperature（ Tg） was slightly decreased after melt spinning due to the thermal decomposition of CDA. CDA fibers with a tensile strength of 1. 06 cN/dtex were prepared by melt spinning. The influence of drawing ratio on the strength and the degree of crystallinity of CDA fibers was also studied. Result showed that the strength and crystallinity of CDA fiber increased with drawing ratio.更多还原