Abstract
The present invention relates to a process for the preparation of water expandable polymer beads, which process comprises the steps of: a) providing a starting composition comprising styrene and a cross-linking agent containing a hydrophilic polymer chain and at least two hydrolysable end-groups having a carbon-to-carbon double bond, b) prepolymerizing the starting composition to obtain a prepolymer composition, c) adding an aqueous dispersion of a modifier-free nanoclay to the prepolymer composition to obtain an inverse emulsion, d) suspending the inverse emulsion obtained by step c) in an aqueous medium to yield an aqueous suspension of suspended droplets and e) polymerizing the monomers in the droplets of the suspension obtained by step d) to obtain the water expandable polymer beads.
| Original language | English |
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| Patent number | WO2015181113 |
| IPC | C08K 3/ 34 A I |
| Priority date | 28/05/14 |
| Publication status | Published - 3 Dec 2015 |