Synthesis of H-shaped complex macromolecular structures by combination of atom transfer radical polymerization, photoinduced radical coupling, ring-opening polymerization, and iniferter processes

Abstract

Three controlled/living polymerization processes, namely atom transfer radical polymerization (ATRP), ring‐opening polymerization (ROP) and iniferter polymerization, and photoinduced radical coupling reaction were combined for the preparation of ABCBD‐type H‐shaped complex copolymer. First, α‐benzophenone functional polystyrene (BP‐PS) and poly(methyl methacrylate) (BP‐PMMA) were prepared independently by ATRP. The resulting polymers were irradiated to form ketyl radicals by hydrogen abstraction of the excited benzophenone moieties present at each chain end. Coupling of these radicals resulted in the formation of polystyrene‐b‐poly(methyl methacrylate) (PS‐b‐PMMA) with benzpinacole structure at the junction point possessing both hydroxyl and iniferter functionalities. ROP of ε‐caprolactone (CL) by using PS‐b‐PMMA as bifunctional initiator, in the presence of stannous octoate yielded the corresponding tetrablock copolymer, PCL‐PS‐PMMA‐PCL. Finally, the polymerization of tert‐butyl acrylate (tBA) via iniferter process gave the targeted H‐shaped block copolymer. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4601–4607

One‐Pot, One‐Step Strategy for the Preparation of Clickable Melamine Based Microporous Organic Polymer Network

“…[11,22] For post-functionalization of organic materials copper catalyzed 1,3-Huisgen dipolar cycloaddition reaction also referred to as the copper-catalyzed azideÀalkyne click abbreviated CuAAC was studied extensively during the last years. [16,[23][24][25][26][27][28][29][30] Due to their efficiency, modularity, chemoselectivity, orthogonality, and regioselectivity, CuAAC reactions are widely used in many fields ranging from material and polymer sciences to the biomedical and pharmaceutical sciences. [23,[31][32][33] In the related work from the authors' laboratory, linear and hyper-branched polymers and block polymers with thermoactive-, photo-, electro-, and bio-functionalities were successfully prepared through CuAAC reactions.…”

Synthesis and analysis of phase segregation of polystyrene‐block‐poly(methyl methacrylate) copolymer obtained by Steglich esterification from semitelechelic blocks of polystyrene and poly(methyl methacrylate)

“…[25] The samples were subjected to pulses at a repetition rate of 180 kHz from a tunable infrared source (quantum cascade lasers-daylight) with wavenumber at 1,728 cm −1 (wavelength corresponding to CO absorption). [26,27] T A B L E 1 Reaction time 24 hr [17] 1 hr [18] 48 hr [22] F I G U R E 1 Steglich esterification used for the synthesis of PS-b-PMMA from functionalized PS and PMMA. PS-b-PMMA, polystyrene-block-poly(methyl methacrylate) [Color figure can be viewed at wileyonlinelibrary.com]…”

“…Song and Cho, [16] Capacchione et al, [17] and Lee et al [14] used anionic polymerization and atom transfer radical polymerization (ATRP) associated with click chemistry to produce PS-b-PMMA. Temel et al [18] and Taskin et al [19] photoinduced the reactive end groups from the homopolymers in order to link both chains, which were first synthesized solely by ATRP.…”

Simple Photochemical Route to Block Copolymers via Two‐Step Sequential Type II Photoinitiation

“…Monomers polymerizing by the same mechanism can be combined using different initiating systems. In our group, we have mainly concentrated on the photochemical routes being involved at least in one mode of the transformation strategy . The approach is usually applied through photopolymerization processes which congregate a wide range of economic and ecological anticipations .…”