Overview on Post-Polymerization Functionalization of Butyl Rubber and Properties

Abstract

Butyl and halobutyl rubber (IIR and HIIR) is an important class of polymeric materials with great potential applications in diverse areas like manufacturing of tires, tubes, adhesives, sealants, pharmaceutical closure, flexible electronics, etc. The IIR and HIIR having exceptional air impermeability, superior oxidative stability, high chemical stability, and better damping properties are attracting significant research attention in improving these products to explore new applications. These properties of IIR and HIIR can be tailored by the introduction of functional moieties via a copolymerization or postpolymerization modification process. The highly sensitive cationic polymerization process can restrict the functionalization with most of the monomers via the copolymerization method. Hence the functionalization of IIR and HIIR can only be carried out using postpolymerization modification methods and those play a crucial role in tailoring the properties of IIR and HIIR. This review summarizes the development of new classes of functionalized IIR and HIIR via the postpolymerization modification method. The improved properties and new applications of the modified IIR and HIIR have been discussed.

Reversible dual crosslinking in anthracenyl functionalized butyl elastomers based on ionic interaction and (4 + 4) cycloaddition mechanisms

“…4 BIIR is widely employed in different sectors, from automotive defence industries to pharmaceutical closures. 5 For high-end applications like these, the products are prone to developing microcracks, fractures, and deformation, all of which can ultimately result in catastrophic failure. Therefore, the fabrication of a self-healing network in the rubber matrix is an approach to extend its service life.…”

Fast, Efficient, Catalyst-Free Epoxidation of Butyl Rubber Using Oxone/Acetone for Improved Filler Dispersion

“…18,19 Therefore, postpolymerization modification is a more feasible way to introduce polar moieties along the backbone of the butyl rubber. 20,21 Behera et al 20 recently published a review on the postpolymerization functionalization of butyl rubber, from which we can understand that epoxidation is a relatively easy way to functionalize butyl rubber in one step as compared to other reactions that often require multiple steps. Meanwhile, the epoxy group in butyl rubber opens the possibility for further functionalization, such as the formation of allylic alcohol and exodiene.…”

Bivalent monomer bearing styryl and five‐membered cyclic dithiocarbonate moieties for orthogonal radical and cationic ring‐opening polymerizations

“…The methods for synthesizing crosslinked polymers can be broadly classified into two categories, that is, (i) post‐polymerization modification of linear polymers having chemoselective functional groups and (ii) polymerization reactions involving multifunctional monomers. In method (i), by introducing highly reactive functional groups into the side chains, it is possible not only to improve and control the performance of polymeric materials but also to synthesize new polymers with a wide variety of performances 1–4 . We have previously synthesized monomers bearing five‐membered cyclic carbonate moieties from epoxides having polymerizable groups and carbon dioxide, and have synthesized polymers bearing five‐membered cyclic carbonate moieties in the side chains by radical polymerization, 5,6 anion ring‐opening polymerization, 7 and ring‐opening metathesis polymerization 8 of the synthesized monomers.…”

“…In method (i), by introducing highly reactive functional groups into the side chains, it is possible not only to improve and control the performance of polymeric materials but also to synthesize new polymers with a wide variety of performances. [1][2][3][4] We have previously synthesized monomers bearing five-membered cyclic carbonate moieties from epoxides having polymerizable groups and carbon dioxide, and have synthesized polymers bearing five-membered cyclic carbonate moieties in the side chains by radical polymerization, 5,6 anion ring-opening polymerization, 7 and ring-opening metathesis polymerization 8 of the synthesized monomers. Furthermore, we and many researchers reported that the networked polymers bearing hydroxy urethane structures as the cross-linking units can be readily synthesized by addition reactions of cyclic carbonates in the side chain with multifunctional amines, because cyclic carbonates react with amines in a highly efficient and selective manner.…”