Cationic polymerization of α,β‐disubstituted olefins. XV. Stereospecific polymerization of butenyl ethers by cationic catalysts

Abstract

synopsisMethyl, ethyl, and isopropyl butenyl ethers, CH&H&H=CHOR, were polymerized with homogeneous catalysts at -78°C. Toluene, methylene chloride, and nitroethane were used as solvents, and BF~O(CZH~)Z and SnClr-CClsC02H were used as catalysts. The stereoregularity of the polymers were compared by x-ray diagrams and intrared absorption ratios. The stereoregularity of polymers increased with increasing content of the trans isomer in the monomer and with increasing polarity of the solvent. In the polymerization of methyl and ethyl butenyl ethers, crystalline polymers were obtained from both the trans and cis isomers. The crystalline polymer prepared from the trans isomer and that from the cis isomer had the same steric structure. This behavior is quite different from that observed in the polymerization of propenyl ethers. It is concluded that the bulkiness of the group on the olefinic 8-carbon plays an important role in the stereospecific polymerization of a,&disubstituted olefins.

Novel degradable methacrylate‐ and p‐vinylphenoxy‐based oligomers, 1. Synthesis and characterization

“…FTIR ( (4) (Tab. I, Scheme 2)*): Bis(imidazo1e-1 -carboxylate) 6 (1,4 g; 4,2 mmol), 3-p-vinylphenoxy-1-propanol (13 g; 8,4 mmol), potassium carbonate (1,7 g; 12 mmol) and a catalytic amount of 18-crown-6 were mixed in 50 mL of dichloromethane.…”

Reinvestigation of the steric structure of poly(methyl propenyl ether) obtained by cationic catalysts

“…For the 15th paper, see ref. (7). Figure 1 shows the NMR spectra of the polymers prepared from the cis isomer (cis/trans: 87/13) and the trans isomer (&./trans: 34/66) of MPE-d3.…”