Patent ID: 9745399
Date: 2017-08-29
CPC Classifications: C08F,D01F

Claim:
1. A method for preparing filamentous particles, said particles consisting of block copolymers, comprising the step of synthesizing by controlled radical emulsion polymerization at least one hydrophobic monomer in the presence of a living macroinitiator derived from a nitroxide, at a reaction temperature of 60 to 120° C., resulting in filamentous particles, wherein: said macroinitiator is water-soluble and comprises a hydrophilic moiety, wherein the mass fraction of the hydrophilic moiety constituting the final block copolymer is less than 25%, the mass percent of the water-soluble macroinitiator in the final block copolymer is between 10% and 50%, and the degree of conversion by mass of the hydrophobic monomer is at least 50% and wherein said filamentous particles have a length of at least 10 microns.