螺旋选择性沉淀聚合制备手性螺旋聚炔球形微粒及其手性分离性能

Synthetic chiral helical polymers and asymmetric polymerization have constituted active research areas. This project is intended to create new methodology for preparing chiral helical polymer particles and explore their practical uses. Currently helix-sense-selective polymerization (HSSP) is majorly limited to solution polymerizations; precipitation polymerization is mainly used to prepare vinyl polymer particles and has not been investigated in depth to prepare helical polymer-based particles. The major contents in the project include: (1) HSSP and precipitation polymerization are judiciously combined in one polymerization system to establish a novel strategy, i.e. helix-sense-selective precipitation polymerization (HSSPP) for preparing novel optically active spherical microparticles composed of helical polymers. Achiral acetylenic monomers undergo HSSPP to provide micro-scaled optically active helical polymer particles, which cannot be prepared by usual emulsion and suspension polymerizations established earlier. (2) Various chiral inducers are used to perform HSSPPs, by which to elucidate the fundamental issues in HSSPP including chiral induction and transference, helicity control, etc. The helical polymer chains will be investigated in detail in terms of packing and forming particles. The effects of helical structures on the particles formation will be explored systemically. (3) Silica and polystyrene particles with surface chiral -C≡C moieties will be used as chiral seeds in HSSPP, thereby providing core/shell structured chiral microparticles; Sol-gel transition and molecularly imprinting technology will be taken for conducting HSSPP, by which to acquire various chiral polymer particles (hybrid, molecularly imprinted, etc.). (4) The obtained chiral microparticles with suitable size and morphology will be used as chiral packing material for HPLC to study their potential applications in chiral recognition/separation. The essential roles of the polymers' chiral helical structures will be elucidated accordingly. The project will provide novel strategies for developing new chiral helical polymer materials.

围绕手性螺旋聚合物和不对称聚合等挑战性前沿科学问题, 本项目将建立手性螺旋聚合物球粒制备新方法。目前螺旋选择性聚合主要集中于溶液聚合体系; 沉淀聚合制备手性聚合物粒子尚待深入研究。本项目(1)将螺旋选择性聚合拓展至沉淀聚合体系, 提出和建立螺旋选择性沉淀聚合(HSSPP)新概念和新方法；通过非手性单体进行HSSPP, 突破手性单体的限制和乳液聚合/悬浮聚合的局限性，填补制备粒径为几微米手性螺旋聚炔球形粒子的学术空白。(2)揭示HSSPP体系中手性诱导/传递的基本科学规律, 探讨聚合物螺旋结构控制和成粒机制。(3)以表面手性-炔基化二氧化硅粒子和聚苯乙烯粒子作为种子, 利用HSSPP制备手性核壳微粒；结合Sol-Gel过程和分子印迹技术，制备杂化、分子印迹等手性微粒。(4)将手性微粒作为色谱柱填料, 探究聚合物螺旋结构在手性识别/分离中的关键作用, 为开发手性螺旋聚合物新材料提供科学基础。

手性科学、手性物质和手性技术近年来受到高度重视。另一方面，生物大分子形成螺旋结构，具有手性特征，这对于生命体维持正常生命活动起到至关重要的作用。因此，针对手性螺旋聚合物的研究，不仅能提升我们对手性以及生物大分子的认识，同时还有助于获得新材料。基于上述研究背景，该项目以手性螺旋聚合物新材料（特别是微纳材料）的设计、制备、性能和应用为研究主题，提出并建立了一系列基于手性螺旋聚炔构筑新材料的方法，获得多种手性新材料，并开展其手性应用研究。在下列方面取得了进展：（1）建立和发展了取代炔单体进行沉淀聚合的方法，继而又建立了此类单体进行分散聚合、种子表面接枝沉淀聚合等方法，为设计制备具有核壳结构以及更复杂结构手性聚合物粒子提供了新途径；（2）将螺旋选择性聚合（HSSP）和沉淀聚合、分散聚合方法结合，建立了螺旋选择性沉淀聚合和螺旋选择性分散聚合等方法；（3）制备了一系列具有手性特征的微纳粒子（球形粒子、非球形粒子），螺旋聚炔构筑的手性杂化粒子和手性复合粒子，以及其他手性微纳材料（纳米纤维等）；（4）开展了手性应用研究（手性拆分、手性识别、对映体选择性诱导结晶、对映体选择性控释等），发现不同种类手性螺旋聚合物间存在协同效应；（5）围绕项目研究主题，适当开展了一些拓展性研究，不仅丰富了手性材料种类，也为进一步开展手性应用研究提供了研究基础。至结题时共发表SCI论文34篇，包括Adv. Funct. Mater.，ACS Nano, ACS Appl. Mater. Interfaces，Macromolecules，Polym. Chem.，Macromol. Rapid Commun.，Chem. Eng. J., Nanoscale 等刊物；基于我们的研究，为Adv. Sci., Polym. Chem.等撰写综述性论文。共培养研究生24人（博士毕业生6人，在读1人；硕士毕业生11人，在读6人）。该项目为手性螺旋聚合物微纳材料构筑以及手性应用研究提供理论指导，也为后续研究打下了坚实的科学基础。