▎ 摘　　要

NOVELTY - Aldehyde-free phase change microcapsule with low super-cooling degree obtained by using polyurethane urea as shell material, n-alkane as core material, and introducing mixture of crystalline resin and multi-dimensional inorganic nanomaterial as compound nucleating agent, and adopting interface polymerization method, and concentration of nucleating agent accounts for 0.1-0.5 wt.% core material. USE - The aldehyde-free phase change microcapsule with low super-cooling degree is useful in field of phase change microcapsule energy storage material. ADVANTAGE - The method is simple and economical. The phase change microcapsule material can maintain relatively low degree of super-cooling, does not appear phase separation phenomenon, and is suitable for long-term cold and hot circulation, has wide development prospect in textile, building and industrial waste heat recovery field. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a method for preparing aldehyde-free phase change microcapsule with low super-cooling degree comprising (1) reacting oligomer polyol with diisocyanate to obtain isocyanate prepolymer mixture, (2) reacting dibasic alcohol and dibasic acid at 200-250℃ for 5-8 hours, cooling to 150-200℃ and thermally insulating for 2 hours to obtain crystalline resin, (3) uniformly mixing isocyanate prepolymer mixture, n-paraffin, crystalline resin and nucleating agent compounded by multi-dimensional inorganic nanomaterial mixture to obtain an oil phase, prepare emulsifier aqueous solution simultaneously to obtain aqueous phase, and (4) dispersing oil phase in the aqueous phase under high-speed stirring, emulsifying at 40-70℃ for 1-20 minutes, adding an amine crosslinking agent, and thermally insulating for 0.5-2 hours, heating up to 90-150℃ and thermally insulating for 2-7 hours, filtering, washing and drying to obtain aldehyde-free phase change microcapsule with low super-cooling degree.