测量应用案例20200810.docxVIP

测量应用案例文献名： Chiral Nematic Liquid Crystal Behavior of Core–Shell Hybrid Rods Consisting of Chiral Cellulose Nanocrystals Dressed with Non-chiral Conformal Polymeric Skins 作者：Ziyue Dong, Zihan Ye, Zhenkun Zhang, Ke Xia, and Pengjiao Zhang Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, 300071 Tianjin, China 摘要：The current work investigates how the nanoscale conformal coating layers of non-chiral polymeric materials can influence the chiral nematic liquid crystal (CLC) behaviors of the rodlike cellulose nanocrystals (CNCs), the bio-derived nanomaterials that have attracted significant attention. For this, we developed strategies to coat the CNC rods on the single-particle level with a homogeneous bioinspired polydopamine (PDA) layer, leading to well-defined core–shell CNC@PDA rods with various PDA coating thicknesses and excellent colloidal stability. Comprehensive investigation revealed that the CNC@PDA hybrid nanorods in concentrated suspensions form well-defined nematic liquid crystal phases with clear phase separation behavior that depend on the rod concentrations and ionic strengths, typical of charged rods. Most intriguingly, the nematic LC phases formed by the CNC@PDA rods with the PDA coating thickness achieved herein are indeed the perfect CLC phases, which form following the classic pathway of nucleation and coalesce of chiral tactoids and have colorful chiral fingerprints standing out from the dark suspensions. The pitches of the CLC phase increase sharply with increasing PDA coating thicknesses and are significantly larger than those of the pristine CNCs. Such observations can be attributed to the blurring effects of the PDA coating on the intrinsic surface chiral features of CNC of whatever origins that drive the formation of the CLC phases, resulting in weakening chiral interactions between CNC@PDA rods. Besides benefiting the understanding of the l