Microemulsion polymer microemulsion

Polymer microemulsion can be prepared by microemulsion polymerization of monomers. There are two kinds of polymer microemulsions: one is O/W normal microemulsion, and the other is W/O inverse microemulsion. The preparation of O/W emulsion generally requires higher emulsifier concentration (even higher than monomer concentration) and the addition of auxiliary emulsifier. Relatively speaking, when preparing W/O microemulsion, it is easier to prepare inverse microemulsion than ordinary microemulsion because the monomer can be partially distributed on the oil-water phase interface to play the role of emulsifier.

The characteristics of microemulsion polymerization are: 1, and the amount of emulsifier and co-emulsifier is large. For example, the typical formula of styrene microemulsion is: styrene (S)4.85% (mass fraction, the same below), sodium dodecyl sulfate (SDS)9.05%, 1- pentanol (co-emulsifier) 3.85%, water 82.5%, KPS 0.27%, and the amount of emulsifier is more than twice that of monomer to form monomer bead diameter. 2. The polymerization speed is fast and the conversion rate is high. The main place to initiate polymerization is that monomer beads with large surface area capture free radicals in water phase to initiate monomer polymerization and nucleation. Average free base number n

The importance of polymer microemulsion is that latex particles belong to nanoparticles. Because of its small particle size and large specific surface area, it is used in coatings, adhesives, impregnants, inks and other fields. When processing and painting wood, stone, concrete, paper or metal parts, it is easy to penetrate into extremely fine patterns and pores to obtain high gloss, high smoothness, high transparency and high strength finishes; Adding styrene-butadiene latex can greatly improve the bonding strength; Polyacrylamide (PMA) inverse microemulsion is a kind of fluid material which is easier to construct and has excellent plugging effect (reducing crude oil permeability) than the existing PMA aqueous solution and PMA dry powder.