Eight xanthates were synthesized to induce living free radical polymerization of vinyl acetate. Four compounds, methyl (4-methoxyphenoxy)carbonothioylsulfanyl acetate, methyl (methoxycarbonothioyl)sulfanyl acetate, methyl (ethoxycarbonothioyl)sulfanyl acetate and methyl (isopropoxycarbonothioyl)sulfanyl acetate were identified as suitable MADIX/RAFT agents, yielding low polydispersity (PDI < 1.2) poly(vinyl acetate) of molecular weights exceeding 5 x 104 g·mol-1. All suitable MADIX/RAFT agents exhibited extended periods of inhibition (0.3 h < tinh < 10 h) andmoderate rate retardation. The abitity of these compounds to control vinyl acetate polymerization can be correlated with the electron density on the central carbon atom of the xanthate. Electrospray ionization mass spectrometric analysis was performed to complete the investigation on the new MADIX/RAFT agents.

Xanthate mediated living polymerization of vinyl acetate: A systematic variation in MADIX/RAFT agent structure

Polymer electrolytes (PEs), a type of solid-state electrolytes (SSEs), have been in contention for nearly half a century to replace organic liquid electrolytes (LEs) that are used in state-of-the-art lithium-ion batteries (LIBs). They are envisaged to accelerate the industrial-scale production of safe, energy-dense, flexible, and thin lithium polymer batteries (LPBs). LPBs are expected to be widely employed for electric propulsion and other futuristic applications, such as flexible electronics and the Internet of Things (IoT). Even though several polymer architectures and chemistries have been attempted so far, PEs that can outperform LEs remain a real challenge. Apart from inadequate Li+-ion transport properties, challenges concerning the integration of PEs and the engineering of compatible, robust, and durable interfaces and interphases at both the electrodes of LPBs must be appropriately addressed. Recently, the in situ polymerization process has been widely employed as a robust fabrication tool for surpassing the intricacies related to the integration of PEs in LPBs. Hence, in this review, we focus on the in situ polymerization processes that employ various polymerization methods (e.g., free-radical polymerization, ionic polymerization, electropolymerization, condensation polymerization, etc.), functional monomers and oligomers (e.g., acrylate, methacrylate, allyl and vinyl ethers, epoxides, etc.), and PE integration strategies for the fabrication of lithium (ion and metal) polymer batteries (LIPBs and LMPBs). Additionally, this review also evaluates the approaches that have been developed until now to implement the in situ processing of LPBs from large-sized pouch cells to flexible-/printable-batteries and even microbatteries.

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In situ polymerization process: an essential design tool for lithium polymer batteries

Emulsion and miniemulsion techniques in preparation of polymer nanoparticles with versatile characteristics.

A considerable amount of the worldwide industrial production of synthetic polymers is currently based on radical polymerization methods. The steadily increasing demand on high performance plastics and tailored polymers which serve specialized applications is driven by the development of new techniques to enable control of polymerization reactions on a molecular level. Contrary to conventional radical polymerization, reversible-deactivation radical polymerization (RDRP) techniques provide the possibility to prepare polymers with well-defined structures and functionalities. The review provides a comprehensive summary over the development of the three most important RDRP methods, which are nitroxide mediated radical polymerization, atom transfer radical polymerization and reversible addition fragmentation chain transfer polymerization. The focus thereby is set on the newest developments in transition metal free systems, which allow using these techniques for biological or biomedical applications. After each section selected examples from materials synthesis and application to biomedical materials are summarized.

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Metal Free Reversible-Deactivation Radical Polymerizations: Advances, Challenges, and Opportunities

Cyanoacrylates (CAs) are well-known fast-setting adhesives, which are sold as liquids in the presence of stabilizers. Rapid anionic polymerization on exposure to surface moisture is responsible for instant adhesion. The more difficult, but synthetically more useful radical polymerization is only possible under acidic conditions. Recommendations on the handling of CAs and the resulting polymers are provided herein. In this review article, after a general description of monomer and polymer properties, radical homo- and copolymerization studies are described, along with an overview of nanoparticle preparations. A summary of our recently reported radical polymerization of CAs, using reversible addition-fragmentation chain transfer (RAFT) polymerization, is provided.

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Radical polymerization of alkyl 2-cyanoacrylates

The present invention relates generally to cyanoacrylate adhesives and, more particularly, to a one-part adhesive, comprising one or more 2-cyanoacrylate esters, one or more bis-silanes and optionally one or more monosilanes and to the use of said adhesive as an instant adhesive with improved water resistance.

Cyanoacrylate adhesive with improved water resistance

Alkyl 2-cyanoacrylates (CAs) are primarily used as instant adhesives, including those sold under the Loctite brand. The adhesive action can be inhibited with acid stabilizers allowing radical polymerization to be employed. The following article details the first attempted controlled/living radical polymerization of alkyl CAs: Reversible addition fragmentation chain transfer (RAFT) polymerization mediated by a poly(methyl methacrylate) dithiobenzoate macroRAFT agent for three different CA monomers (ethyl 2-cyanoacrylate, n-butyl 2-cyanoacrylate, and 2-phenylethyl cyanoacrylate) allowed the preparation of the first block copolymers of this challenging but commercially important monomer class. Nevertheless, GPC with UV detection indicated significant loss of the RAFT end-group for all three CAs limiting control/living character. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1397–1408

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Reversible addition–fragmentation chain transfer polymerization of alkyl-2-cyanoacrylates: An assessment of livingness

A process for the preparation of an electron deficient olefin precursor, the process comprising transesterifying a 2-electron withdrawing group-substituted methylene compound of Formula (I) with an alcohol in the presence of a catalyst comprising a lanthanide or transition metal element to produce an electron deficient olefin precursor of Formula (I); wherein EWG represents an electron withdrawing group; and R represents straight chain, branched, cyclic or fused C­1-20­ alkyl; C2-20 alkenyl, C2-20 alkynyl, and C6-20 aryl or C7-20 alkaryl, with or without substitution or interruption by one or more heteroatoms wherein the R is of the product is different to that of the starting compound; and optionally separating from the mixture the electron deficient olefin precursor substantially free from starting materials, catalysts or by-products. The 2-electron withdrawing group-substituted methylene and the electron deficient olefin precursor are preferably a cyanoacetic acid and cyanoacetate respectively. The lanthanide element is preferably selected from niobium, zirconium, scandium or ytterbium. The transition metal or lanthanide preferably has one or more ligands selected from halogens, triflates, mesylates, nitrates or tosylates. The electron withdrawing group is preferably selected from cyano, nitrile, alkoxy, aryloxy, carboxyl, sulphonic acids, carbonyls, halogens, nitro, isocyanate, sulfoxide and phosphine oxide.

Cormac Duffy

Papers

Radical polymerization of alkyl 2-cyanoacrylates

Cyanoacrylate adhesive with improved water resistance

Reversible addition–fragmentation chain transfer polymerization of alkyl-2-cyanoacrylates: An assessment of livingness

Process for preparing electron deficient olefin precursors

The Reversible Addition-Fragmentation Chain Transfer (RAFT) polymerization of cyanoacrylates