POLYUREA CAPSULES CROSS-LINKED WITH CHITOSAN

• Main Author: FENG, Linsheng
• Format: Patent
• Language: English; French; German
• Published: 27.03.2024
• Subjects: AGRICULTURE; ANIMAL AND VEGETABLE OILS, FATS, FATTY SUBSTANCES AND WAXES; ANIMAL HUSBANDRY; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES, AS HERBICIDES; CANDLES; CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; COMPOSITIONS BASED THEREON; DERIVATIVES THEREOF; DETERGENT COMPOSITIONS; DETERGENTS; ESSENTIAL OILS; FATTY ACIDS THEREFROM; FISHING; FORESTRY; HUMAN NECESSITIES; HUNTING; HYGIENE; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; MEDICAL OR VETERINARY SCIENCE; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; PERFUMES; PEST REPELLANTS OR ATTRACTANTS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; PLANT GROWTH REGULATORS; POLYSACCHARIDES; PREPARATIONS FOR MEDICAL, DENTAL, OR TOILET PURPOSES; PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTSTHEREOF; PRODUCING (PRESSING, EXTRACTION), REFINING AND PRESERVINGFATS, FATTY SUBSTANCES (e.g. LANOLIN), FATTY OILS AND WAXES,INCLUDING EXTRACTION FROM WASTE MATERIALS; RECOVERY OF GLYCEROL; RESIN SOAPS; SOAP OR SOAP-MAKING; THEIR PREPARATION OR CHEMICAL WORKING-UP; THEIR RELEVANT APPARATUS; TRANSPORTING; TRAPPING; USE OF SINGLE SUBSTANCES AS DETERGENTS

An improved process of forming polyurea and chitosan microcapsules encapsulating a benefit agent is described. The process comprises forming a water phase comprising hydrolyzing chitosan in an acidic medium at a pH of 6.5 or less for an extended period and combining with a polyisocyanate. The reaction product of the hydrolyzed chitosan and polyisocyanate yields a microcapsule having improved release characteristics, with enhanced degradation characteristics in OECD test method 301B.