Method for the controlled polymerization of fluoromonomers
US10377843B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 11, 2015 |
| Grant date | Aug 13, 2019 |
| Priority date | — |
| Expiry date | May 11, 2035 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L2201/52
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The invention pertains to a method for emulsion polymerization of at least one fluoromonomer, said method comprising: (i) providing at least one aqueous emulsion comprising at least one surfactant and a monomer mixture [mixture (M)] comprising at least one fluoromonomer [monomer (F)] and optionally at least one additional monomer, and at least one RAFT/MADIX agent; (ii) initiating the polymerization of said monomer mixture in said aqueous emulsion adding at least one radical initiator; (iii) continuing the polymerization by adding additional amounts of said mixture (M) and said RAFT/MADIX agent, until converting the targeted amount of said mixture (M), and (iv) terminating the polymerization and recovering a latex of fluoropolymer [polymer (F)]; wherein the amount of RAFT/MADIX agent is comprised between 0.1 and 0.5% moles, with respect to the total amount of converted monomers of said monomer mixture, and wherein the amount of said RAFT/MADIX agent present in the aqueous emulsion when initiating the polymerization in step (ii) is of at most 50% with respect to the total amount of said RAFT/MADIX agent.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.