【摘要】 为大幅降低二醋酸纤维素(CDA)的熔融温度,利用哈克转矩流变仪分别制备了CDA/1-乙基-3-甲基咪唑醋酸盐([EMIM]Ac)、CDA/二甲基亚砜(DMSO)和CDA/[EMIM]Ac/DMSO 3种体系,分析了这3种体系制备过程中温度及转矩与时间的关系,并利用X射线衍射仪、热重分析和流变仪等研究了这3种体系的结构与性能。研究结果表明:离子液体[EMIM]Ac对CDA具有良好的增塑作用,CDA/[EMIM]Ac体系可形成均一相态;DMSO对CDA增塑作用较弱,CDA在DMSO中既不能溶解也不能熔融,其以溶胀态分散在CDA/DMSO体系中;以DMSO代替部分[EMIM]Ac,不仅可降低成本,更能促进[EMIM]Ac的增塑作用;CDA/[EMIM]Ac及CDA/[EMIM]Ac/DMSO 2种体系的热分解温度虽远低于原料CDA,但又远高于它们各自的熔融流动温度,熔融加工稳定性好。更多还原

【Abstract】 Cellulose diacetate( CDA) has high melting temperature,and is an important derivative of cellulose. In order to significantly reduce the melt processing temperature of CDA,the systems of CDA /1-ethyl-3-methylimidazolium acetate( [EMIM]Ac), CDA / dimethyl sulfoxide( DMSO) and CDA /[EMIM]Ac / DMSO were prepared in HAAKE rheocord. The curves of temperature-time and torque-time in the process of three systems were analyzed,respectively. The structures and performances of the systems were investigated by XRD,TGA and rheometer,respectively. The results show that,ionic liquid[EMIM]Ac is so effective as a plasticizer for CDA that the plasticizing melting system of CDA /[EMIM]Ac is a homogeneous one. The plasticizing effect of DMSO to CDA is weak. CDA can neither dissolve nor melt in DMSO,and it can scatter in the plasticizing system of CDA / DMSO in the swollen state. Replacing of part of [EMIM]Ac with DMSO can not only reduce costs,but also promote plasticizing effect of [EMIM]Ac. The melt processing stability of the plasticizing melting systems of CDA /[EMIM]Ac and CDA /[EMIM]Ac / DMSO is good because their thermal decomposition temperature is well above their melt flow temperature,although their thermal decomposition temperature are lower than that of raw CDA.更多还原