Precise synthesis and surface structures of architectural per-and semifluorinated polymers with well-defined structures

摘要

This article reviews the synthesis by methodologies based on living/controlled polymerization,of well-defined perfluorinated and semifluorinated(FL)homopolymers,chain-end-functionalized polymers with FL group(s),block copolymers having FL segment(s),chain-end-multifunctionalized polymers with a definite number of FL groups,and star-branched and dendrimer-like hyperbranched polymers having FL segment(s).Most of the FL groups and FL segments comprise perfluoroalkyl and/or semifluoroalkyl side chains,represented as a CF3(CF2)_(m-1)(CH2)_n moiety.In the FL polymers herein presented,except for FL homopolymers,such FL components are chemically linked to non-FL polymer chains and readily separated at the molecular level,followed by self-organization,to form a variety of nanoscale molecular assemblies at the surface of a film,in bulk,and in solution.The FL components possess many unique and interesting characteristics,such as remarkably low surface energies,low friction coefficients,strong incompatibility with conventional hydrocarbon-based polymers,high thermal stability,chemical inertness,and phenyl-free liquid crystalline formation.The surface,solution,and bulk properties of polymer structures including FL units reflect these characteristics of the self-organization of polymers with FL components is of particular interest.Moreover,non-FL polymer chains may enhance the solubility of FL polymers,and render molecular assemblies more changeable in shape,form,and size.Recent reports on these subjects are presented in this review.