Novel Mesogenic Vinyl Ketone Monomers and Their Based Polymers

Abstract

In the present research, we have synthesized new vinyl ketone monomers with mesogenic substituents, namely, 8-(3′-chloro-4′-pentyl-[1,1′-biphenyl-4-oxy)oct-1-en-3-one (BVK) and 8-[2′-chloro-4′′′-octyl-[1,1′:4′,1′′:4′′,1′′′-quaterphenyl-4-oxy]oct-1-en-3-one (QVK). The comparison of BVK, QVK, and previously synthesized 8-((4′′-((1R,4S)-4-butylcyclohexyl)-2′-chloro-[1,1′,4′,1′′-terphenyl]-4-yl)oxy)oct-1-en-3-one (TVK) has revealed that all of them are able to form crystals, while their ability to exhibit liquid crystalline behavior depends on the number of phenyl substituents attached to the para-position of the phenoxy group and is observed for TVK and QVK only. All of the monomers are able to achieve self-polymerization upon heating and free radical polymerization in bulk or in solution under the action of the common radical initiator AIBN. We have also succeeded in the RAFT polymerization of the synthesized vinyl ketones BVK and TVK using asymmetrical trithiocarbonates. The synthesized poly(vinyl ketones) exhibit LC behavior and are able to undergo photodegradation upon UV irradiation.

Pentafluorophenyl vinyl ketone: Synthesis, radical polymerization, copolymerization, and polymer degradation under ultra‐violet irradiation

“…The photosensitivity of vinyl ketone monomers is determined by photochemistry of the carbonyl group; the latter property has been studied by many research groups ~50 years ago 17,35,36 . Accordingly, the ability to decompose under the influence of UV radiation is a key property of polyvinyl ketones and is used in the development of new materials and technologies 37–40 . Photolysis of aliphatic ketones proceeds via two simultaneous reactions 41 (Scheme 4).…”

“…17,35,36 Accordingly, the ability to decompose under the influence of UV radiation is a key property of polyvinyl ketones and is used in the development of new materials and technologies. [37][38][39][40] Photolysis of aliphatic ketones proceeds via two simultaneous reactions 41 (Scheme 4). The Norrish type I reaction causes the scission of the molecule and produces free radicals.…”

Synthesis and Physicochemical Properties of Functional Biphenyl Derivatives Designed for Anisotropic Nanomaterials

“…S-(-)-Октан-2-ил-4'-гидрокси-[1,1'-бифенил]карбоксилат (2) [11,12], этил-6-(4'-пентил-3'хлор-[1,1'-бифенил-4-окси])гексаноат (3) [10], этил-6-(4'-циано-[1,1'-бифенил]-4-илокси)гексаноат (4) [13,14] были получены аналогично методам, которые приведены в указанных публикациях.…”

“…В продолжение этих исследований [6], учитывая их несомненную актуальность и практическую значимость, представляло интерес синтезировать новые соединения, обладающие наличием различных функциональных групп, способствующих специфическому взаимодействию с наночастицами, и изучить свойства анизотропных нанокомпозитов на их основе. Для осуществления данной цели была рассмотрена возможность получения разнообразных функциональных производных бифенила, включая хиральные, из коммерчески доступных 4',4бифенилдикарбоновой кислоты (I), 4'-гидрокси-4бифенилкарбоновой кислоты (II), 4'-гидрокси-4цианобифенила (III) и описанного нами ранее 4'пентил-3'-хлор-4-гидроксибифенила (IV) [10].…”

Controlled photodegradation of phenyl vinyl ketone polymers by reinforcement with softer networks

“…The photodegradation of PVK polymers has been reported in both polymer solutions and in material levels through Norrish II process (Scheme 1b). [27][28][29][30][31] However, the rate of the degradation can vary depending on the power of the UV source, with the degradation times changing from couple of days to few years. 32 In earlier studies, PVK containing thermoplastic elastomers have been synthesized, with fast and substantial degradation (>24 h) under strong source of UV light.…”