Living radical polymerization of diisopropyl fumarate to obtain block copolymers containing rigid poly(substituted methylene) and flexible polyacrylate segments

Abstract

Living radical polymerizations of diisopropyl fumarate (DiPF) are carried out to synthesize poly(diisopropyl fumarate) (PDiPF) as a rigid poly(substituted methylene) and its block copolymers combined with a flexible polyacrylate segment. Reversible addition-fragmentation chain transfer (RAFT) polymerization is suitable to obtain a high-molecular-weight PDiPF with well-controlled molecular weight, molecular weight distribution, and chain-end structures, while organotelluriummediated living radical polymerization (TERP) and reversible chain transfer catalyzed polymerization (RTCP) give PDiPF with controlled chain structures under limited polymerization conditions. In contrast, controlled polymerization for the production of high-molecular-weight and well-defined PDiPF is not achieved by atom transfer radical polymerization (ATRP) and nitroxide-mediated radical polymerization (NMP). The block copolymers consisting of rigid poly(substituted methylene) and flexible polyacrylate segments are synthesized by the RAFT polymerization.

Facile synthesis of graft copolymers containing rigid poly(dialkyl fumarate) branches by macromonomer method

“…PDiPF is a rigid poly(substituted methylene) and one may concern that the M n,GPC values contain a large error due to the difference in the Mark–Houwink–Sakurada parameters of PDiPF and polystyrene used for the GPC calibration. It has been reported that in the living radical polymerization of DiPF, the difference between the M n,GPC value determined by polystyrene standards calibration and the M n,NMR value determined by the characteristic peaks due to the ω‐end group and DiPF repeating unit was less than 10%, and also the M n,GPC values agreed with the theoretical values . Based on the fact, it is reasonably expected that the M n,GPC values determined in this study do not contain a large error and the M n,GPC / M n,NMR values can be used to discuss a trend in the series of experiments.…”

“…To modify poly(dialkyl fumarate)s with maintaining their poly(substituted methylene) structure, graft and block copolymers containing a poly(dialkyl fumarate) chain are required. Block copolymers consisting of rigid poly(diisopropyl fumarate) (PDiPF) and flexible poly(meth)acrylate segments were successfully synthesized by using living radical polymerization techniques . However, limitations regarding to the order of polymerization of fumarates and (meth)acrylates were pointed out in the report, and thus the synthesis of block copolymers containing multiple poly(dialkyl fumarate) segments is expected to be difficult.…”

Thermal and mechanical properties of random copolymers of diisopropyl fumarate with 1‐adamantyl and bornyl acrylates with high glass transition temperatures

“…As an increase in the DiPF content in the copolymers with AdA and BoA, the detection of transition temperatures became difficult as shown in the DSC thermograms in Figure . It was reported in the literatures that the transitions of the dimethyl and diethyl esters of the PDRFs were also clearly observed below 100 °C by the DSC analysis, while it was not detected for the di‐ tert ‐butyl ester . The T g value increased with an increase in the AdA content for the P(DiPF‐ co ‐AdA)s, while a small change was observed for the T g values of P(DiPF‐ co ‐BoA)s. These results indicated that the chain mobility was influenced by both the amount of flexible methylene spacers introduced into the main chain and the steric bulkiness of the ester groups in the side chain of the copolymers.…”

“…Poly(dialkyl fumarate)s (PDRFs) have unique characteristics regarding both polymer production processes and polymer physical properties . For example, the rate of radical polymerization of dialkyl fumarates (DRFs) as the 1,2‐disubstituted ethylene monomers increased with an increase in the steric bulkiness of the ester alkyl groups.…”

“…In contrast, only small amount of the DRF units were introduced into the copolymers with 1,1‐disubstituted ethylene monomers such as methyl methacrylate, methacrylonitrile, vinylidene chloride, and α‐methylstyrene because the addition rate of the propagating radicals produced from these 1,1‐disubstituted ethylenes to the DRF monomers was much small due to the steric hindrance between the propagating radicals of vinylidene monomers and DiPF as the 1,2‐disubstituted ethylene monomer. It should also be noted that the fumarates as the trans isomers show a polymerization reactivity higher than that of the maleates as the cis isomers …”