| 摘要 |
Polymers of unsaturated monomers containing a single methylene group attached to a carbon atom by a double bond and polymerizable by peroxy compounds, are prepared by polymerizing the monomers in an alkaline water phase in the presence of an organic peroxy-dicarbonate formed in the presence of the monomer using an organic haloformate present in the monomer phase and a peroxide present in the water phase. The peroxide may be hydrogen peroxide or sodium peroxide, and specified haloformates are methyl, ethyl, isopropyl, n-propyl, isobutyl, n-butyl, amyl, hexyl, heptyl, nonyl, lauryl, benzyl, cyclohexyl, tetrahydrofurfuryl and cinnamyl chloroformates. Many suitable monomers are listed including vinyl esters; vinyl and isopropenyl ketones; vinyl ethers; isobutylene; styrene and nuclear-substituted styrenes; acrylic, methacrylic and choracrylic esters; acrylonitrile; methacrylonitrile; acrylamide; vinyl and vinylidene halides and N-vinyl heterocyclic compounds and an example describes the polymerisation of vinyl chloride. The pH of the medium may be maintained by sodium bicarbonate, sodium hydroxide or sodium phosphate buffers. Dispersing agents, e.g. sodium stearate, sodium oleate, ammonium oleate, potassium palmitate, sodium myristate, rosin or dehydrogenated rosin soaps, gelatin, soluble starch, gum tragacanth, gum acacia, cellulose derivatives, sodium alginate, agar agar, glue, Turkey red oil, sodium sulphonates and partially hydrolysed polyvinyl acetate, may be employed.
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