Friable shell microcapsules, process for preparing the same and method of use thereof
AssigneeISP Investments Inc.
InventorsKishor Kumar Mistry, Assim Fiaz, Abdul Wahab Hussain, Terry Crutcher
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Abstract
The present application describes a microcapsule comprising: (i) a lipophilic core material, and (ii) a microcapsule shell, wherein microcapsule shell formed from oil-in-water emulsion polymerisation of monomer mixture consisting essentially of: (a) greater than 70 to about 99% by weight of at least one polyfunctional ethylenically unsaturated monomer, (b) about 1 to about 30% by weight of at least one unsaturated carboxylic acid monomer or its ester, and (c) about 0 to about 30% by weight of at least one vinyl monomer. Also provides process for preparing the same and its method of use in various applications.
Claims17
A microcapsule comprising:
- i. a lipophilic core comprising a lipophilic core material, and
- ii. a friable and highly crosslinked microcapsule shell;
- wherein said microcapsule shell is formed from oil-in-water emulsion polymerisation of a monomer mixture consisting essentially of:
- (a) greater than 70 to about 99% by weight of pentaerythritol triacrylate (PETA) (b) about 1 to about 30% by weight of at least one unsaturated carboxylic acid monomer or its ester selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, 2-carboxylethyl acrylate, C1-C24 alkyl ester of acrylic acid, C1-C24 alkyl ester of methacrylic acid, and combinations thereof, and (c) about 0 to about 30% by weight of at least one vinyl monomer selected from the group consisting of N-vinyl pyrrolidone, N-vinyl caprolactam, 2-hydroxylethyl pyrrolidone methacrylate, octyl acrylamide, acryloxyethyltrimethyl ammonium chloride, 2-hydroxyethyl methacrylate and combinations thereof;
- and
- wherein the lipophilic core is encapsulated by the friable and highly crosslinked microcapsule.
The microcapsule according to claim I. wherein said unsaturated carboxylic acid monomer or its ester is present in an amount from about 10 to about 30% by weight of total monomers in polymer shell.
A process for preparing microcapsules comprising the steps of:
- A. preparing an oil phase comprising:
- i. a monomer mixture consisting essentially of:
- (a) greater than 70 to about 99% by weight of pentaerythritol triacrylate (PETA) (b) about 1 to about 30% by weight of at least one unsaturated carboxylic acid monomer or its ester selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, 2-carboxylethyl acrylate, C1-C24 alkyl ester of acrylic acid, C1-C24 alkyl ester of methacrylic acid, and combinations thereof, and (c) about 0 to about 30% by weight of at least one vinyl monomer selected from the group consisting of N-vinyl pyrrolidone, N-vinyl caprolactam, 2-hydroxylethyl pyrrrolidone methacrylate, octyl acrylamide, acryloxyethyltrimethyl ammonium chloride, 2-hydroxyethyl methacrylate and combinations thereof, and
- ii. at least one lipophilic core material;
- B. preparing a separate aqueous phase comprising at least one polymeric emulsion stabilizer and water;
- C. adding the oil phase of step (A) to the aqueous phase of step (B) under mechanical shear to form an oil-in-water emulsion;
- D. polymerizing the oil-in-water emulsion of step (C) through radical polymerisation by heating the emulsion to at least 80° C. and employing at least one initiator to produce core-shell microcapsules comprising an entrapped lipophilic core material and a friable and highly crosslinked polymer shell to result in a suspension of core-shell microcapsules in water.
A consumer care composition comprising a microcapsule comprising:
- (i) a lipophilic core comprising a lipophilic core material, and (ii) a friable and highly crosslinked microcapsule shell, wherein said microcapsule shell is formed from oil-in-water emulsion polymerisation of a monomer mixture consisting essentially of (a) greater than 70 to about 99% by weight of pentaerythritol triacrylate (PETA) (b) about 1 to about 30% by weight of at least one unsaturated carboxylic acid monomer or its ester selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, 2-carboxylethyl acrylate, C1-C24 alkyl ester of acrylic acid, C1-C24 alkyl ester of methacrylic acid, and combinations thereof, and (c) about 0 to about 30% by weight of at least one vinyl monomer selected from the group consisting of N-vinyl pyrrolidone, N-vinyl caprolactam, 2-hydroxyle thyl pyrrrolidone methacrylate, octyl acrylamide, acryloxyethyltrimethyl ammonium chloride, 2-hydroxyethyl methacrylate and combinations thereof;
- wherein the lipophilic core is encapsulated by the friable and highly crosslinked microcapsule shell.
A method of using a microcapsule comprising employing said microcapsule as a delivery matrix to deliver lipophilic core materials for industrial compositions that are related to agrochemicals, textiles, paper, mining, oil industry, water treatment, adhesives. coatings, plastics, sealants, construction, paints, inks and dyes onto different substrate surfaces such as skin, hair, or textiles, and wherein said microcapsule comprises:
- (i) at least one lipophilic core comprising a lipophilic core material, and (ii) a friable and highly crosslinked microcapsule shell, wherein said microcapsule shell is formed from oil-in-water emulsion polymerisation of a monomer mixture consisting essentially of:
- (a) greater than 70 to about 99% by weight of pentaerythritol triacrylate (PETA) (b) about 1 to about 30% by weight of at least one unsaturated carboxylic acid monomer or its ester selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, 2-carboxylethyl acrylate, C1-C24 alkyl ester of acrylic acid, C1-C24 alkyl ester of methacrylic acid, and combinations thereof, and (c) about 0 to about 30% by weight of at least one vinyl monomer selected from the group consisting of N-vinyl pyrrolidone, N-vinyl caprolactam, 2-hydroxylethyl pyrrrolidone methacrylate, octyl acrylamide, acryloxyethyltrimethyl ammonium chloride, 2-hydroxyethyl methacrylate and combinations thereof;
- wherein the lipophilic core is encapsulated by the friable and highly crosslinked microcapsule shell.
Dependencies are inferred from the claim text.