A new method of incorporating nano-sized titanium dioxide(nano-TiO_(2))particles onto the shell of photochromic microencapsulated phase change materials was introduced,in order to address issues of easy degradation of...A new method of incorporating nano-sized titanium dioxide(nano-TiO_(2))particles onto the shell of photochromic microencapsulated phase change materials was introduced,in order to address issues of easy degradation of photochromic dyes’core components caused by ultraviolet(UV)irradiation and residual organic emulsifiers.Using nano-TiO_(2)as the Pickering emulsion stabilizer and cross-linked polyurethane as the shell material,a composite protective structure was constructed to encapsulate core materials with phase-change and photochromic properties,thereby forming photochromic phase change microcapsules(TPT-MPCMs)with UV protection and thermal insulation.Characterization results show that the core-shell structured TPTMPCMs possessed high light transmittance,with a particle size of 5-15μm and a latent heat of 116.2 J·g^(-1).The highly cross-linked shell formed by xylitol and isophorone diisocyanate effectively protected the core from thermal degradation up to 180°C,while the nano-TiO_(2)shell surface allowed maintaining the UV responsiveness of microcapsules after exposure to intense UV irradiation for 5 h.This strategy significantly improves the long-term stability and service life of photochromic microcapsules under harsh environments,opening up broad prospects for their applications in fields such as outdoor anti-counterfeiting labels,intelligent temperature-controlled coatings,and multifunctional smart textiles.展开更多
基金the financial support for this research from the National Natural Science Foundation of China(Grant No.51573135)。
文摘A new method of incorporating nano-sized titanium dioxide(nano-TiO_(2))particles onto the shell of photochromic microencapsulated phase change materials was introduced,in order to address issues of easy degradation of photochromic dyes’core components caused by ultraviolet(UV)irradiation and residual organic emulsifiers.Using nano-TiO_(2)as the Pickering emulsion stabilizer and cross-linked polyurethane as the shell material,a composite protective structure was constructed to encapsulate core materials with phase-change and photochromic properties,thereby forming photochromic phase change microcapsules(TPT-MPCMs)with UV protection and thermal insulation.Characterization results show that the core-shell structured TPTMPCMs possessed high light transmittance,with a particle size of 5-15μm and a latent heat of 116.2 J·g^(-1).The highly cross-linked shell formed by xylitol and isophorone diisocyanate effectively protected the core from thermal degradation up to 180°C,while the nano-TiO_(2)shell surface allowed maintaining the UV responsiveness of microcapsules after exposure to intense UV irradiation for 5 h.This strategy significantly improves the long-term stability and service life of photochromic microcapsules under harsh environments,opening up broad prospects for their applications in fields such as outdoor anti-counterfeiting labels,intelligent temperature-controlled coatings,and multifunctional smart textiles.
