Kirila Tatyana, Smirnova Anna, Razina Alla, Tenkovtsev Andrey, Filippov Alexander
Institute of Macromolecular Compounds of the Russian Academy of Sciences, Bolshoy pr., 31, 199004 Saint Petersburg, Russia.
Polymers (Basel). 2020 Apr 3;12(4):800. doi: 10.3390/polym12040800.
Star-shaped six-arm poly-2-alkyl-2-oxazine and poly-2-alkyl-2-oxazoline with hexaaza [2]orthoparacyclophane derivative core were synthesized successfully using cationic ring-opening polymerization. Conformational behavior of prepared polymer stars were investigated by the methods of molecular hydrodynamics and optics in molecular dispersed solutions. It was shown that conformation characteristics of star-shaped polypeptoids depends on arm length, while the chemical structure weakly affects the behavior of the studied polymers in solutions. This behavior is caused by the close equilibrium rigidity of arms. The star-shaped polypeptoids have relatively high intramolecular density. All synthesized stars exhibit LCST behavior. Phase separation temperature depends on arm structure. It is lower for poly-2-alkyl-2-oxazines, monomer units of which contains one methylene group more than monomers of poly-2-alkyl-2-oxazoline.
采用阳离子开环聚合法成功合成了具有六氮杂[2]对环芳烷衍生物核心的星形六臂聚-2-烷基-2-恶嗪和聚-2-烷基-2-恶唑啉。通过分子流体动力学和光学方法研究了制备的聚合物星型分子在分子分散溶液中的构象行为。结果表明，星形聚肽类化合物的构象特征取决于臂长，而化学结构对所研究聚合物在溶液中的行为影响较弱。这种行为是由臂的紧密平衡刚性引起的。星形聚肽类化合物具有相对较高的分子内密度。所有合成的星型分子均表现出最低临界溶液温度（LCST）行为。相分离温度取决于臂的结构。对于聚-2-烷基-2-恶嗪，其单体单元比聚-2-烷基-2-恶唑啉的单体多一个亚甲基，相分离温度较低。
