Process for the preparation of polymer particles
AssigneeNOVA Chemicals (International) S.A.
InventorsJeroen Joost Crevecoeur, Eric Wilhelmus Johannes Frederik Neijman, Laurentius Nicolaas Ida Hubertus Nelissen, Johannes Maria Zijderveld
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Abstract
Particles of a copolymer of a vinyl arene and a copolymerizable compound containing a polar moiety and a vinyl moiety containing water may be prepared by forming a mixture of monomers and small amounts of water and polymerizing under agitation to 20 to 70% conversion and then suspending the mass in water and finishing the polymerization. The resulting polymer beads contain finely dispersed water which is useful as an environmentally acceptable blowing agent.
Claims9
A process for the preparation of polymer particles containing a vinyl arene polymer comprising:
- a) forming a mixture comprising a vinyl arene monomer, from 0.001 to 5 weight % based on the weight of the vinyl arene monomer of a copolymerizable compound containing a polar moiety and a vinyl moiety and from 1 to 20 weight % based on the weight of the vinyl arene monomer of water;
- b) pre-polymerizing the mixture under agitation at rates up to 500 revolutions per minute at a temperature from 40° C. to 150° C. to a conversion of from 20 to 70% to form insitu an emulsifier and to emulsify the water in the pre-polymerized mixture;
- c) suspending the pre-polymerized mixture in water to form an oil in water suspension;
- d) polymerizing the resulting suspension at a temperature from 60° C. to 140° C.;
- and
- e) recovering the resulting polymer particles.
Dependencies are inferred from the claim text.