Copolymerization of vinyl acetate with 1-octene and ethylene by cobalt-mediated radical polymerization

in Journal of Polymer Science. Part A, Polymer Chemistry (2007), 45(12), 2532-2542

The cobalt-mediated radical polymerization of vinyl acetate was extended to copolymerization with I-alkenes (ethylene or 1-octene). In agreement with the low amount of I-alkene that could be incorporated ... [more ▼]

The cobalt-mediated radical polymerization of vinyl acetate was extended to copolymerization with I-alkenes (ethylene or 1-octene). In agreement with the low amount of I-alkene that could be incorporated into the copolymer, a gradient structure was predictable, but a. rather low polydispersity was observed. A poly(vinyl acetate)-b-poly(octene) copolymer was also successfully synthesized, leading to a poly (vinyl alcohol)-b-poly(octene) amphiphilic copolymer upon the methanolysis of the poly (vinyl acetate) block. [less ▲]

Cobalt-mediated radical polymerization (CMRP) of vinyl acetate initiated by redox systems: Toward the scale-up of CMRP

in Macromolecules (2006), 39(24), 8263-8268

A redox initiating system was developed in order to bypass 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile) (V70) as the initiator of the cobalt-mediated radical polymerization (CMRP) of vinyl acetate ... [more ▼]

A redox initiating system was developed in order to bypass 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile) (V70) as the initiator of the cobalt-mediated radical polymerization (CMRP) of vinyl acetate (VAc) in the presence of cobalt(II) acetylacetonate (Co(acac)(2)). It is indeed a problem to stock up with V70 because of needed storage at -20 degrees C during transportation. This paper reports on the controlled CMRP of VAc initiated by ascorbic acid combined with either lauroyl peroxide or benzoyl peroxide at 30 degrees C. Substitution of citric acid for ascorbic acid results in faster polymerization whereas the polymerization control is maintained. All these improvements facilitate the implementation of the vinyl acetate CMRP and open the door to the scale-up of the process. [less ▲]

Cobalt-mediated radical polymerization of vinyl acetate in miniemulsion: Very fast formation of stable poly(vinyl acetate) latexes at low temperature

in Macromolecular Rapid Communications (2006), 27(1), 37-41

Poly(vinyl acetate) macroinitiators end-capped by a Co(acac)(2) complex (PVAc-Co(acac)(2)), prepared in bulk by cobalt-mediated radical polymerization (CMRP), are used for the controlled radical ... [more ▼]

Poly(vinyl acetate) macroinitiators end-capped by a Co(acac)(2) complex (PVAc-Co(acac)(2)), prepared in bulk by cobalt-mediated radical polymerization (CMRP), are used for the controlled radical polymerization of vinyl acetate in miniemulsion to give high-molecular-weight polymers and high monomer conversion. Stable poly(vinyl acetate) latexes with solid contents ranging from 25 to 30 wt.-% are prepared within unusually short reaction times (similar to 1 h) at low temperatures (0-30 degrees C). [less ▲]