Method of manufacturing fluoropolymers
AssigneeAlliedSignal Inc.
InventorsThomas F. McCarthy, Yan Chen, Eric J. Rainal
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Abstract
The present invention provides a novel, optionally surfactant-free process for controlling particle number, particle size, and/or particle size distribution. The method of the invention also significantly improves monomer to polymer conversion rates, as well as, increases the level of polymer solids which can be emulsified/dispersed in water without polymer flocculation. Specifically, the improved process provides an aqueous dispersion of up to about 48% polymer solids in water in the absence of surfactant. The resulting fluoropolymers dispersions may be used in resin and coating applications.
Claims19
An emulsion polymerization process carried out in the absence of an addition of surfactants prior to an addition of an initial charge of a radical initiator comprising:
- reacting a mixture comprising a fluoroolefin, water and the radical initiator the radical initiator comprising a reducing agent and an oxidizing agent wherein the radical initiator is added in at least two charges, the initial charge and a continuous charge and wherein the amount of the reducing agent in the initial charge is at least from about 500 to about 10,000 PPM based on the total weight of polymer produced and the amount of the oxidizing agent in the initial charge is at least from about 500 to about 10,000 PPM based on the total weight of polymer produced.
Dependencies are inferred from the claim text.