RAFT Polymerization of Vinylthiophene Derivatives and Synthesis of Block Copolymers Having Cross-Linkable Segments

Abstract

The polymerization of three vinylthiophene derivatives, 2-vinylthiophene (2VT), 3-vinylthiophene (3VT), and 2,5-dibromo-3-vinylthiophene (DB3VT), was carried out by reversible addition-fragmentation chain transfer (RAFT) process using six different chain transfer agents (CTAs). The novel doubly polymerizable monomer, DB3VT, undergoes controlled radical polymerization via the RAFT process, followed by Suzuki coupling reaction. Two dithiobenzoate-type RAFT agents, phenylethyl dithiobenzoate (CTA 2) and cumyl dithiobenzoate (CTA 3), were the most efficient to obtain poly(DB3VT) with controlled molecular weights and low polydispersities (M w /M n =1.05-1.15). Good control of the polymerization of DB3VT was confirmed by the linear increase in the molecular weight with the conversion and the ability to extend the chain by a second addition of the monomer. Chain extension from poly(methyl methacrylate) to DB3VT could be well controlled under suitable conditions and provided block copolymers having crosslinkable poly(DB3VT) segments with as-designed chain structures and low polydispersities. The block copolymers were also synthesized by RAFT polymerization of DB3VT using poly(methyl acrylate) as a macro-chain transfer agent (macro-CTA). Modifications of the 2,5-dibromide group of poly(DB3VT) by Suzuki coupling reaction using difunctional boronic acid afforded a network material, whereas a soluble composite having an extended π-structure was obtained by the coupling reaction of the block copolymer, poly(methyl methacrylate)-b-poly(DB3VT).

Analysis of a high‐throughput cone‐and‐plate apparatus for the application of defined spatiotemporal flow to cultured cells

“…Compound 9 was purchased from Sigma‐Aldrich and used without further purification. The starting materials and some intermediates (Compounds 1 ,27 2 ,28 4 ,29 6 ,30 7 ,31 8 ,32 M5 ,33 and M6 21) were synthesized according to the literature procedures. Other reagents were obtained from Sinopharm Chemical Reagent (Shanghai, China).…”

Rylene bisimide-based nanoparticles with cross-linked core and thermoresponsive shell using poly(vinyl amine)-based block copolymers

“…Recently, several approaches have been investigated to synthesize cross-linked coreeshell nanoparticles with characteristic optoelectronic properties by self-assembly of block copolymers and Suzuki-coupling reactions [40e43]. For example, we recently reported the synthesis of cross-linked coreeshell nanoparticles with p-conjugated components in the core via the self-assembly of block copolymers prepared by RAFT polymerization of 2,5-dibromo-3-vinylthiophene [40,41] and 4-bromophenyl vinyl sulfide [43]. In these systems, an in situ Suzuki coupling reaction was conducted between the cross-linkable (di)bromide groups in block copolymers and various diboronic acid compounds following the formation of micelles to afford stable cross-linked nanoparticles.…”

Synthesis of RAFT‐Mediated Amphiphilic Graft Copolymeric Micelle Using Dextran and Poly (Oleic Acid) toward Oral Delivery of Nifedipine

“…Besides, the copolymer shows narrow PDI (=1.238), signifying the controlled nature of polymerization . Again, the monomodal GPC curve of the copolymer with higher molecular weight (as compared to dextran, macroinitiator, and RAFT agent‐mediated dextran) indicates the successful polymerization of oleic acid …”