Formation of high molecular weight polythiiranes in aqueous‐organic media

Abstract

The influence of water on the polymerization of thiirane and 2-methylthiirane with CdCO, was studied. The polymerization process takes place only when a large interface monomerwater is formed. This is achieved by the presence of an amount of water in the reaction mixture which is comparable with that of the monomer. The polarity of the solvent does not influence the rate of formation of poly(2-methylthiirane). The polymerization is carried out in the mass of monomer or in the presence of an alcohol and a solvent not miscible with water.

Cationic Polymerization of p-Methoxystyrene in Water with Dodecylbenzenesulfonic Acid and Ytterbium Triflate: Evidence for an Inverse Emulsion Process

“…The most applied system deals specifically with cyclosiloxanes, whose patent and article survey grows exponentially since it has been discovered in the late 1950s . Other monomers are known to be quite reactive in anionic polymerization, such as alkyl cyanoacrylates, methylidene malonates, or episulfides . Recent studies also described the polymerization of less reactive monomers, such as glycidyl ethers, N -carboxy-α-amino acids, or p -alkoxystyrenes (including p -methoxystyrene or p MOS).…”

“…An approach to facilitate polymerization against termination was proposed in early patents dealing with episulfide polymerization. 4a-c The polymerization is catalyzed by Cd(OH) 2 or Zn(OH) 2 , generated by cadmium or zinc oxide hydrolysis. Propagation is fast even in the presence of an excess of water, and molar masses of more than 10 4 g/mol were obtained.…”

“…A coordination mechanism was proposed 4d and confirmed by the head-to-tail microstructure of the polymer. Polymerization is believed to occur at the surface of the solid catalyst surrounded by the monomer (“pearl polymerization”) 4b4e…”

“…Polymerization is believed to occur at the surface of the solid catalyst surrounded by the monomer (“pearl polymerization”) 4b4e…”

Synthesis and applications of olefin‐contaning polymers

“…In analogy with anionic coordination catalysis the polymer chain does not propagate via a free chain end but grows like a "hair out of a root (Ref. 42 ) .…”