了单体BAB6和手性剂质量分数对PSLC薄膜电光性能和网络微观形貌的影响.结果表明,随着BAB6质量分数增加,PSLC薄膜的聚合物网眼尺寸变小,透过率降低,饱和电压增加,响应时间缩短;随着手性剂质量分数增加,聚合物网眼尺寸缩小,液晶畴变小,驱动电压增加,响应时间进一步下降.当液晶、单体、手性剂的质量比为100ʒ5ʒ10时,制得了电光性能优良,响应时间为2ms的PSLC薄膜.
3结论与展望
为了制备光电性能优良的液晶器件,研究者们尝试了各种不同的方法,发现了醇的种类、表面活性剂、阻聚剂、紫外光固化时间、纳米掺杂、液晶含量和引发剂含量对聚合物分散液晶的光电特性存在一定的影响.引入醇分子能加快液晶复合体系的光聚合反应速率,提高了单体的最终转化率;增加SA的含量能改善PDLC的电光性能.阻聚剂对PDLC混合物的固化产生了延缓聚合作用,降低了PDLC膜的关态透过率;随着紫外光固化时间的延长,PDLC的阈值电压和饱和电压升高,关态透光率、记忆效应和最大透光率下降;Fe3O4的添加虽然会降低PDLC的透射率,但会降低驱动电压;随着液晶含量的增加,电光性能变好,随着引发剂含量的增加,最大透光率增加;单体质量分数为30%,聚合温度为343.2K,制备的PDLC光电性能较为理想.聚合电场频率、不同单体配比、聚合网络的锚定作用、单体浓度、聚合电场波形、单体BAB6和手性剂含量对聚合物稳定液晶的电光性能存在一定的影响.聚合电场频率高,阻碍单体的扩散,形成的聚合物网络致密,网孔较小,响应速度快,关态透过率低,阈值电压和饱和电压大;聚合物体锚定的增强使聚合物稳定液晶的稳定性提高;3种不同的聚合电场波形(方波、正弦波和三角波)能控制聚合物网络的形貌,改善PSLC的光电性能.随着聚合物稳定液晶和分散液晶高分子智能调光玻璃的研究日趋加深,新的材料和器件设计也会日渐成熟.
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