Rapid and Systematic Access to Quasi‐Diblock Copolymer Libraries Covering a Comprehensive Composition Range by Sequential RAFT Polymerization in an Automated Synthesizer

Abstract

A versatile, cost-effective approach to the rapid, fully unattended preparation of systematic quasi-diblock copolymer libraries via sequential RAFT polymerization in an automated synthesizer is reported. The procedure is demonstrated with the synthesis of a 23 member library of low dispersity poly(butyl methacrylate)-quasiblock-poly(methyl methacrylate) covering a wide (fivefold) range of molar mass for the second block in a one-pot, sequential, RAFT polymerization.

Online Monitoring of Polymerizations: Current Status

“…The solution is sent to the injection loop of a GPC (4), where a sample gets injected in a fixed time interval. The samples are detected by inline detectors (5). Excess reaction solution from the injection loop and column is sent to waste (6).…”

“…[3,4] A different kind of automatization in polymer synthesis is demonstrated by automated parallel synthesizers (Chemspeed reactors). [5,6] By such an approach, for example (block)copolymer libraries can be synthesized in a rapid, fully unattended manner.…”

RAFT Polymerization – Then and Now

“…High throughput RAFT polymerization in an automated synthesizer has been developed to provide polymer libraries through the synthesis of di-tri-and higher order multi-block copolymers in a 'hands-free' operation (150,151,198,199). Recent work has seen the implementation of freeze-thaw degassing procedures (200) and the application of the methodology to determine RAFT agent activity (52,53,161) and copolymerization reactivity ratios (201).…”

Reversible addition-fragmentation chain transfer (co)polymerization of conjugated diene monomers: butadiene, isoprene and chloroprene

“…Butadiene was then introduced to the reactor whilst polymerization was underway with addition beginning at about 60% styrene conversion without stopping polymerization. The triblocks formed following addition of butadiene should thus be a gradient copolymer and the materials formed can thus be considered as ‘quasiblocks’; i.e. they have polystyrene‐ block ‐poly(styrene‐ grad ‐butadiene) segments.…”