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Azobenzene‐containing liquid crystal polymers (azo‐LCPs) with reactive groups attract much attention due to the combined properties of liquid crystallinity, photoresponsivity and reactivity, which make them promising in designing intelligent photo‐driven soft actuators. Herein, a post‐polymerization modification strategy is used to prepare a series of reactive azo‐LCPs using the trans‐esterification reaction of poly(pentafluorophenyl acrylate) with functional alcohols. These reactive azo‐LCPs show good capabilities in fabricating fibers via a simple thermal‐drawing method and subsequent crosslinking reaction with diamine under mild conditions. Furthermore, the prepared fibers exhibit reversible deformation behaviors under the alternate irradiation of UV and visible light (365/530 nm). This facile synthetic strategy is expected to open up new possibilities for fabricating photo‐driven actuators.

Azobenzene‐containing liquid crystal polymers (azo‐LCPs) with reactive groups attract much attention due to the combined properties of liquid crystallinity, photoresponsivity and reactivity, which make them promising in designing intelligent photo‐driven soft actuators. Herein, a post‐polymerization modification strategy is used to prepare a series of reactive azo‐LCPs using the trans‐esterification reaction of poly(pentafluorophenyl acrylate) with functional alcohols. These reactive azo‐LCPs show good capabilities in fabricating fibers via a simple thermal‐drawing method and subsequent crosslinking reaction with diamine under mild conditions. Furthermore, the prepared fibers exhibit reversible deformation behaviors under the alternate irradiation of UV and visible light (365/530 nm). This facile synthetic strategy is expected to open up new possibilities for fabricating photo‐driven actuators. [ABSTRACT FROM AUTHOR]

The biomedical applications of polyesters and polycarbonates are of interest due to their potential biocompatibility and biodegradability. Confined by the narrow scope of monomers and the lack of controlled polymerization routes, the biomedical-related applications of polyesters and polycarbonates remain challenging. To address this challenge, ring-opening copolymerization (ROCOP) has been exploited to prepare new alternating polyesters and polycarbonates, which would be hard to synthesize using other controlled polymerization methods. This review highlights recent advances in catalyst development, including the emerging dinuclear organometallic complexes and metal-free Lewis pair systems. The post-polymerization modification methods involved in tailoring the biomedical functions of resultant polyesters and polycarbonates are summarized. Pioneering attempts for the biomedical applications of ROCOP polyesters and polycarbonates are presented, and the future opportunities and challenges are also highlighted.

ABSTRACT: Post‐polymerization modification (PPM) of polymers is extremely beneficial in terms of designing brand new synthetic pathways toward functional complex polymers. Fortunately, the new developments in the field of organic chemistry along with controlled/living radical polymerization (CLRP) techniques have enabled scientists to readily design and synthesize the functionalized‐polymers for wide range of applications via the PPM. In this regard, the reactivity of para‐fluorine atom in the fluorinated aromatic structures toward the nucleophilic substitution reactions has made the polymers possessing this group to become a very strong candidate that can undergo efficient PPM. Besides, it has been proven that the thiol‐functionalized compounds react with the para‐fluorine atom of the pentafluorophenyl group more rapidly and efficiently than the amine‐ and the hydroxyl‐functionalized compounds. Furthermore, the milder experimental conditions to achieve quantitative conversions have led to the reaction between the thiol and the structures possessing pentafluorophenyl groups to be referred to as a click‐type reaction. Given this information, this review article aims to present the scientific developments regarding the thiol‐para‐fluoro “click” (TPF‐click) chemistry, and its impact on PPM to construct novel polymeric structures. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1181–1198 [ABSTRACT FROM AUTHOR]