Interplay of structural factors in molecular dynamics of microphase-separated or microphase- mixed structures of polyurethanes revealed by solid-state NMR and dielectric spectroscopy

Chemical Physics Impact

Vjacheslav V. Zuev¹  Stepan A. Ostanin¹  Maxim V. Mokeev²  Aleksandr S. Sakhatskii³  Dmitry V. Pikhurov⁴ 

[1] ITMO University, Kronverkskiy pr. 49, Saint-Petersburg 197101, Russian Federation;Institute of Macromolecular Compounds of the Russian Academy of Sciences, Bolshoi pr. 31, Saint-Petersburg 199004, Russian Federation;Saint-Petersburg State University, 7/9 Universitetskaya nab., Saint-Petersburg 199034, Russian Federation;Varnish-paint plant ''CRONOS SPb”, st. Polevaya Sabirovskaya 42, St. Petersburg 197183, Russian Federation;

关键词: Molecular dynamics;    Polyurethane;    Solid-state NMR;    Dielectric spectroscopy: microphase structure;   

DOI  :  

来源: DOAJ

【 摘 要 】

A set of aromatic-oxyaliphatic polyurethanes (PUs) with different mass fractions of components also containing fluorinated fragments was synthesized and their molecular dynamics studied using various solid-state NMR techniques and dielectric spectroscopy. In contrast to the common model suggested by Cooper and Tobolsky in 1966, the rigid domains of microphase separated PUs are formed not only by units containing urethane bonds, but also by oxyethylene fragments which form a common rigid phase. The urethane bonds and oxyethylene fragments are incorporated into both rigid and soft phases. Good agreement with Cooper and Tobolsky model is observed only when solubility parameters are significantly different for the hard and soft segments, such as hydrocarbon aromatics and perfluoroaliphatic blocks.

【 授权许可】

Unknown