Magnetizable composite microspheres of hydrophobic crosslinked polymer, process for preparing them and their application in biology
AssigneeRhone-Poulenc Chimie
InventorsDominique Charmot, Christine Vidil
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Abstract
Magnetizable composite microspheres approximately from 0.05 to 10 .mu.m in diameter, comprising a core of magnetizable particles and a shell of a hydrophobic crosslinked copolymer formed from a vinylaromatic monomer and a crosslinking emulsifying polymer. The microspheres are obtained by the pre-emulsification in water of a magnetic fluid composed of magnetizable particles dispersed in a vinylaromatic monomer and in a crosslinking emulsifying polymer, polymerization, separation of the magnetizable microspheres and optional redispersion in water. The microspheres are useful in biological applications.
Claims9
Magnetizable composite microspheres of hydrophobic crosslinked vinylaromatic polymer which are approximately from 0.05 to 10 .mu.m in diameter, and which comprise:
- (1) a core comprising magnetizable particles less than 300.times.10.sup.-4 .mu.m in diameter coated with an approximately mono molecular layer of a non-water-soluble dispersing agent;
- and
- (2) a shell consisting essentially of a hydrophobic crosslinked copolymer formed from at least one hydrophobic vinylaromatic monomer and at least one polyethylenically unsaturated emulsifying polymer which is soluble in said vinylaromatic monomer(s) and capable of crosslinking with said vinylaromatic monomer(s), wherein said shell is substantially free from said magnetic particles relative to said core.
Dependencies are inferred from the claim text.