| 摘要 |
A carrier polymer is soaked in a monomer system then led into a temp. regulating fluid in which the monomer is polymerised at controlled reaction velocity. When the desired degree of graft obtained, the excess monomer is washed out. Materials: carrier is a vinyl polymer, e.g. polyvinylidene fluoride or perhalogenated fluorocarbon polymer, or a copolymer. It is used in film form. Monomer is styrene, temp. bath is conc. brine, e.g. conc. aq. Na2SO4 soln. Cross-linking agents and redox catalysts can be used and solvent. Contact time 1-8 hrs at 40 degrees-90 degrees C. Ion-exchange gps. can be produced in the graft-polymer by sulphonation or chloromethylation followed by amination. Used: esp. for ion exchange membranes, is not limited to this. |
