| 摘要 |
<p>A process is claimed for the prodn. of cross linked copolymer pearls contg. 50-99.5 mol.% units of a monovinyl monomer and 0.5-50 mol.% mu its of a cross linking monomer. The copolymerisation is carried out in aq. suspension by free radical polymerisation in the presence of 0.01-10 millimols. (per mol. monomer) of an alkynic or allylic unsaturated monomer as reaction moderator. The copolymers are pref. based on 50-99.5 mol. %, esp. 80-90 mol. % units of a vinylaromatic monomer such as styrene, vinyltoluene, ethylvinylbenzene, chloromethylstyrene, etc., and 0.5-50 esp. 1-20 mol. % of a cross linking agent such as divinylvenzene, trimethylolpropanetrimethacrylate, ethyleneglycoldimethacrylate, divinyltoluene, etc. The prods. are esp. useful for conversion into ion exchange resins. The modified copolymers have improved resistance to osmotic shock (swelling pressures caused during acid/base cycling).</p> |
