RAFT step-growth polymerization of bis-acrylamides and their facile degradation

Abstract

Demonstrated is the successful A2 + B2 RAFT step-growth polymerization of bis-acrylamides using a bifunctional trithiocarbonate chain transfer agent as the comonomer. Remarkably, homopropagation typical of acrylamides leading to branching...

Tuning the Mechanical Properties of 3D‐printed Objects by the RAFT Process: From Chain‐Growth to Step‐Growth

“…To achieve this goal, a rapid photoinduced RAFT‐SUMI reaction is needed. While various vinyl monomers, including acrylates, [20] acrylamides, [21] maleimides, [22] vinyl ethers and alkylenes, [23] have been explored for RAFT step‐growth polymerization, none have exhibited feasibility for photoinduced 3D printing. Here, we expanded the scope of monomers suitable for RAFT step‐growth polymerization (e.g., vinyl acetate and xanthate) and subsequently employed this novel monomer–RAFT agent pair for photoinduced 3D printing.…”

Injectable, self-healing and degradable dynamic hydrogels with tunable mechanical properties and stability by thermal-induced micellization

“…The triblock copolymers were prepared by RAFT polymerization, and the trithiocarbonate group was located in the middle of the polymer chains. The trithiocarbonate group could be cleaved by a nucleophilic reagent, such as ethanolamine, 43 which may induce the degradation of the hydrogels. Thus, to examine their degradation, the H4 samples were immersed in a solution of pH 7.4 (Fig.…”

Preparation of fluorinated polyesters by reversible addition–fragmentation chain transfer step-growth polymerization

“…Reversible addition–fragmentation chain transfer (RAFT) step-growth polymerization is a new polymerization technique proposed by You et al 47–55 It uses bifunctional alkenes and RAFT chain-transfer agents (CTAs) as the monomers, which efficiently yield single monomer unit insertion (SUMI) adducts via a chain-transfer cycle. 54,56 Therefore, it may combine the merits of step-growth polymerization and RAFT polymerization.…”

“…For example, it is user-friendly and only requires mild polymerization conditions, affording polymers with a readily functionalized backbone. By adjusting the structure of the monomer and/or CTA, a variety of functional groups can be introduced into the polymer backbone, such as the ester bond, 47–53,57 ether bond, 48–50,53 silico–oxygen bond, 47 disulfide bond, 48,51,52 and amido bond. 52 Besides, the obtained polymer contains one (AB type) or two (A 2 + B 2 type) RAFT CTA(s) in each repeat unit, which provides a versatile platform for the post-polymerization regulation of polymer topologies.…”