A series of microencapsulated blends of waterborne polyurethane (WBPU) as a matrix polymer and phase change material octadecane as a domain material were prepared in the presence of emulsifier. Nylon fabrics were coated with the coating materials formulated from microencapsulated blends, thickener, and hardener. The morphology and thermal behaviors of microencapsulated octadecane and WBPU/octadecane-coated nylon fabrics were investigated using SEM, DSC, and KES-F7. The size of octadecane microspheres increased with increasing octadecane contents. However, the size of microcsphere (1-6 mu m) decreased with increasing emulsifier contents. Delta H-fusion, Delta H-crystallization, and their filling efficiencies of octadecane in film samples were found to increase with increasing microencapsulated blends, thickener, and hardener contents. Especially, thickener and hardener could function in trapping microencapsulated octadecane. Thermal characteristic Q(max) (J/cm(2) s) values of WBPU/octadecane-coated nylon fabrics are much higher than those of the control nylon fabric and WBPU-coated nylon fabrics, indicating that the nylon fabrics coated with WBPU/octadecane blends have cooler touch sensation compared with nylon fabrics and WBPU-coated nylon fabrics. (c) 2005 Wiley Periodicals, Inc.