| 摘要 |
The invention concerns a method for preparing in two steps an organic dialkyl peroxydicarbonate solution with long alkyl chains particularly adapted for the polymerising in aqueous suspension halogenated monomers, which consists in using an inorganic salt in the step for preparing the dialkyl peroxydicarbonate (first step) and separating the latter by extraction using an water-insoluble solvent (second step). The dialkyl peroxydicarbonates with long alkyl chains, preferably of diethylhexyl, are used in the polymerisation in aqueous suspension of halogenated monomers in the form of a solution in a water-insoluble liquid dialkyl alkanecarboxylate. The preferred solvents are water-insoluble liquid dialkyl alkanecarboxylates derived from C4-C10 alkanedicarboxylic acids and C2-C12 alkanols. The concentration in peroxydicarbonate of said solutions ranges between 15 and about 50 wt. % Said method produces polymers with improved purity. |
