Gradient Methylidene-Ethylidene Copolymer via C1 Polymerization: an Ersatz Gradient Ethylene-Propylene Copolymer

Abstract

We report the first synthesis of a gradient methylidene-ethylidene copolymer via a living C1 polymerization. The copolymer has a similar chemical structure as the corresponding ethylene-propylene copolymer. To achieve this goal a new and convenient source of the ethylide monomer, diethylsulfoxonium ethylide, was developed for the introduction of the methyl branch in the polymer backbone. The gradient copolymer contains a gradual change of instantaneous methyl branch content from 0% on one end of the polymer chain to 63% on the other end. Thermal analysis revealed that the gradient copolymers have a narrow glass transition temperature range with values intermediate between those of linear polyethylene and atactic polypropylene.

Terpolymers from Borane‐Initiated Copolymerization of Triphenyl Arsonium and Sulfoxonium Ylides: An Unexpected Light Emission

“…Our group was also used polyhomologation of dimethylsulfoxonium methylide to obtain well‐defined PM‐based linear, miktoarm star, and brush copolymers by designing/synthesizing novel borane initiators or by combining polyhomologation with other living/controlled living polymerization methods, such as anionic, cationic, atom transfer radical, ring‐opening, and ring‐opening metathesis polymerization . Later, efforts were focused in the synthesis of substituted ylides, such as dimethylaminophenyloxosulfoxonium methylide, diethylsulfoxonium methylide, (dimethylamino)tolylsulfoxonium cyclopropylide, with the hope of obtaining poly(substituted methylene) . Although the homopolymerization of substituted sulfoxonium ylides were unsuccessful (owing to the steric hindrance around boron centers), the copolymerization of these subsituted ylide monomers with sulfoxonium methylide was however successful.…”

Asymmetric Copolymers: Synthesis, Properties, and Applications of Gradient and Other Partially Segregated Copolymers

“…Stepwise gradient and related asymmetric copolymers have been prepared by different methods including NMP, [50,[73][74][75][76][77] ATRP, [78] RAFT, [60,79,80] as well as by living anionic polymerization [27,81] and C1 copolymerization, a polyhomologation reaction that uses methylene and ethylidene ylide monomers as substrates. [34] An example of the stepwise approach is the preparation of styrene (St)-n-butyl acrylate (nBA) copolymers using a "many shot" RAFT emulsion polymerization (Figure 7). [80] Linear and V-shaped stepwise gradients were prepared using this method.…”

“…By increasing the number of blocks, a continuous composition profile can be approached as closely as desired. Stepwise gradient and related asymmetric copolymers have been prepared by different methods including NMP, ATRP, RAFT, as well as by living anionic polymerization and C1 copolymerization, a polyhomologation reaction that uses methylene and ethylidene ylide monomers as substrates …”

“…Many techniques have been used for the preparation of asymmetric copolymers, including anionic [27] and cationic [28][29][30][31][32][33] polymerizations, C1 polymerization, [34] catalyst transfer polycondensation, [35] catalyzed copolymerization of olefins [36] and epoxides, [37] ring-opening metathesis polymerization (ROMP) [38][39][40][41][42] and various RDRP techniques (e.g., atom transfer radical polymerization (ATRP), [43][44][45][46][47][48] nitroxide-mediated polymerization (NMP), [49][50][51][52][53][54][55][56] organometallic-mediated radical polymerization (OMRP), [57] and reversible addition-fragmentation chain transfer (RAFT) [22][23][24][58][59][60][61] ).…”

Phase Behavior of Gradient Copolymer Melts with Different Gradient Strengths Revealed by Mesoscale Simulations

“…Finally, the gyroid (GYR) nanostructure, which belongs to the class of bicontinuous morphologies, exhibits two interpenetrating networks in all three dimensions. Advances in polymer synthesis [6][7][8][9][10] have now allowed for the preparation of copolymers with controlled sequence chemistry [11]. For example, a new class of copolymer called taper has been prepared by inserting an additional block with a gradual change of between the pure and blocks.…”