长链离子液体单体及其聚合物的合成与聚集机理

Synthesis and aggregation behavior of long-chain ionic liquid monomer and its polymer

将十六烷基的非极性长链引入乙烯基咪唑结构中,合成了具有聚集行为的离子液体型单体[C16VIm+][Br-]及其聚合物Poly[C16VIm+][Br-],并利用IR和XRD对其结构进行表征。通过热失重(TGA)和吸热放热(DSC)分析表明,[C16VIm+][Br-]和Poly[C16VIm+][Br-]均具有良好的热稳定性,在降温过程存在过冷现象。通过设计不同的混合溶液体系,获得[C16VIm+][Br-]与Poly[C16VIm+][Br-]的不同形貌大聚集体。其中,[C16VIm+][Br-]具有双亲性结构,培养体系对其聚集体形成有重要影响,形成的大聚集体形貌主要为海胆状、羽毛状、羊毛状和发丝状。聚合物Poly[C16VIm+][Br-]在V(甲苯)∶V(甲醇)=2∶1混合溶液体系中形成稳定的新型两相体系,且随着其上层轻相溶剂挥发,快速自发形成粒径均匀的核壳结构球形聚集体。采用电导法研究[C16VIm+][Br-]和Poly[C16VIm+][Br-]在不同溶液体系中的聚集行为,并计算分析临界聚集浓度(CAC)和反离子结合度(β)等参数值。结果表明:在所有的研究体系中,CAC值随着温度的升高而减小,反离子结合度β则出现升高趋势,从而有利于大聚集体的形成。

A non-polar long-chain of cetyl was introduced into the structure of vinylimidazole,and an ionic liquid monomer[C16VIm+][Br-]and its polymer Poly[C16VIm+][Br-]were synthesized.The structure was characterized by IR and XRD,and analysis by TGA and DSC shows that both[C16VIm+][Br-]and Poly[C16VIm+][Br-]has good thermal stability,and there is supercooling during the cooling.In addition,by designing different mixed solution systems,large aggregates with different morphologies of[C16VIm+][Br-]and Poly[C16VIm+][Br-]were successfully obtained.[C16VIm+][Br-]has an amphiphilic structure,and the system has an important influence on its aggregate formation.The morphology of the large aggregates formed by the monomer was like sea urchin,feather,wool,and hair.Poly[C16VIm+][Br-]formed a stable new two-phase system in a mixed solution of V(toluene)∶V(methanol)=2∶1.As the light phase solvent on the upper layer evaporates,a spherical core-shell spherical aggregate with uniform particle size is quickly and spontaneously produced.The conductance method was used to study the aggregation behaviors of[C16VIm+][Br-]and Poly[C16VIm+][Br-]in different solution systems.The parameters were calculated and discussed,including critical aggregation concentration(CAC)and counterion binding degree(β).Studies show that in all the research systems,the CAC value decreases with increasing temperature,and the counterion binding degreeβtends to increase,which is conducive to the formation of large aggregates.