Method of making hydrophobic copolymers hydrophilic
AssigneeDow Corning Corporation
InventorsMaris Jazeps Ziemelis, William Robb Roy Park
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Abstract
A method for altering a macroporous cross-linked hydrophobic copolymeric lattice produced by precipitation polymerization in a solvent of at least one monounsaturated ester monomer and at least one polyunsaturated ester monomer soluble therein, in order to render the hydrophobic copolymeric lattice hydrophilic. The method involves saponifying the hydrophobic copolymeric lattice by reacting the surface of the hydrophobic copolymeric lattice with an aqueous alkali. The surface can also be rendered hydrophilic by polymerizing an acrylate monomer onto the lattice in order to form a surface containing carboxylic acid sites. The carboxylic acid sites formed on the surface of the lattice are converted to carboxylate anions.
Claims8
A hydrophilic copolymer comprising a cross-linked hydrophobic copolymer, produced by precipitation polymerization in a solvent of at least one monounsaturated ester monomer and at least one polyunsaturated ester monomer soluble therein, the copolymer containing a monomer polymerized on the surface of the hydrophobic copolymer, in order to form carboxylic acid sites on the surface of the hydrophobic copolymer, the copolymer being in the form of unit particles of less than about one micron in average diameter, fused unit particles of sizes in the range of about twenty to eighty microns in average diameter, and aggregates of clusters of fused unit particles of sizes in the range of about two hundred to about twelve hundred microns in average diameter, the monomer polymerized on the surface being selected from the group consisting of acrylic acid and methacrylic acid.
A hydrophilic copolymer comprising a cross-linked hydrophobic polymer, produced by precipitation polymerization in a solvent of at least one polyunsaturated ester monomer soluble therein, the polymer containing a monomer polymerized on the surface of the hydrophobic polymer, in order to form carboxylic acid sites on the surface of the hydrophobic polymer, the polymer being in a form including unit particles of less than about one micron in average diameter, fused unit particles of sizes in the range of about twenty to eighty microns in average diameter, and aggregates of clusters of fused unit particles of sizes in the range of about two hundred to about twelve hundred microns in average diameter, the monomer polymerized on the surface being selected from the group consisting of acrylic acid and methacrylic acid.
Dependencies are inferred from the claim text.