Block copolymers polymeric libraries

Abstract This chapter highlights the application of controlled/ living polymerization (CLP) techniques in automated parallel synthesizers for both optimizing reaction parameters as well as preparing copolymer libraries. Special attention is given to the use of CLP techniques for constructing well-defined copolymer libraries. Furthermore, alternative strategies for the preparation of block copolymer libraries are discussed. 

NMP is as successful as RAFT polymerization for the construction of block copolymers. A small library of block copolymers comprised of poly(styrene) (PSt) and poly(ferf-butyl acrylate) (FYBA) was designed and the schematic representation of the reaction is depicted in Scheme 10 [49]. Prior to the block copolymerization, the optimization reactions for the homopolymerization of St and f-BA were performed as discussed in this chapter (e.g., see Sect. 2.1.2). Based on these results,... 

Scheme 13 Schematic representation of the synthetic route towards a library of PStm-[Ru]-PEO block copolymers, where m and n denote the degree of polymerization (DP) of PSt and PEO, respectively, and where -[Ru]- represents the bis(terpyridine) mthenium complex...

Fig. 10 Illustrations of the microchannel confined surface-initiated polymerization (p-SIP) route for producing gradient polymer brush libraries a route for making polymer molecular weight and block copolymer libraries b route for making statistical copolymer libraries. Red arrows show the flow of monomer solution from a syringe pump used to gradually fill the microchannel. See text for details...

The groups of Kramer and Hawker provided an example where the target polymer could be made using sequential CFR polymerizations, but CuAAC simplified the process and made it possible to obtain the polymer with a precise molecular weight and a low polydispersity index (PDl). Attempts to make poly(benzyl methacrylate)-b-poly(butyl acrylate) with equal volume fractions of each block to be used for the determination of order-disorder transition (ODT) led to materials with imprecise volume fractions and PDls higher than 1.3. Instead, by using preformed homopolymers that were then coupled by CuAAC, the authors were able to make a small library of covalent diblock copolymers with low PDIs, while also performing fewer total reactions. 

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