Helical Polymers: Optical Activity

螺旋聚合物：光学活性

• 批准号: 8914631
• 负责人: Otto Vogl
• 金额: --
• 依托单位: Polytechnic University of New York
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-04-01 至 1995-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8914631&HistoricalAwards=false
• 关键词: Helical; Polymers; Optical; Activity

This research deals with an investigation to design, synthesize, and characterize helical polymers and to study their properties. The primary thrust will still be the preparation of isotactic helical polymers, those polymers whose structure consists of only isotactic macromolecular helices of one screw sense and which display optical activity based on macromolecular asymmetry. The goals are: a.)To identify clearly the initial propagation mechanism by determining the absolute configuration of all the linear oligomer of the chloral polymerization now obtained in the crystalline state. b.)To prepare polyperhaloacetaldehydes of one screw sense by initiation with bulky chiral initiators. c.)To use pure chiral fluorochlorobromoacetaldehyde as monomer for the perhaloacetaldehyde polymerization to ascertain the influence of the chiral center of the monomer on the handedness of the helical polymer. d.)To establish the limits of this newly discovered method of measuring the optical rotation of solids. e.)To perfect the potential energy calculations of configuration and conformation for the developing of the helix during chiral initiation and follow it up with computer simulation to show the "locking" of the helix based on the bulkiness of the isotactic polymer chain. f.)To investigate the synthesis of helical polymers of one screw sense in the presence of polarized light and the fabrication of helical polymers in the solid state or by direct monomer casting techniques to forum oriented high tenacity fibers.

本研究旨在设计、合成、表征螺旋聚合物并研究其性能。主要的推动力仍然是制备全同立构螺旋聚合物，这些聚合物的结构仅由一个螺旋方向的全同立构大分子螺旋组成，并且基于大分子不对称性显示旋光性。目标是：a.）通过测定结晶状态下获得的氯醛聚合的所有线性低聚物的绝对构型，明确确定初始增长机制。B.）用大体积手性引发剂引发制备单螺向聚全卤乙醛。c.）以纯的手性氟氯溴乙醛为单体进行全卤乙醛聚合，考察单体手性中心对螺旋聚合物手性的影响。d.）确定这种新发现的测量固体旋光度的方法的极限。e.）的范围内。完善了手性引发过程中螺旋形成的构型和构象势能计算，并通过计算机模拟，揭示了基于等规聚合物链体积的螺旋“锁定”现象。f.）研究偏振光作用下单螺旋聚合物的合成，以及固态或单体直接浇铸法制备螺旋聚合物的方法。