Gamma-ray radiation has always been a convenient and effective way to modify the inter- facial properties in polymer blends. In this work, a small amount of trimethylolpropane triacrylate （TMPTA） was incorporated in...Gamma-ray radiation has always been a convenient and effective way to modify the inter- facial properties in polymer blends. In this work, a small amount of trimethylolpropane triacrylate （TMPTA） was incorporated into poly（ethylene terephthalate） （PET）/random terpolymer elastomer （ST2000） blends by melt-blending. The existence of TMPTA would induce the crosslinking of PET and ST2000 molecular chains at high temperatures of blend- ing, resulting in the improvement in the impact strength but the loss in the tensile strength. When the PET/ST2000 blends were irradiated by gamma-ray radiation, the integrated me- chanical properties could be enhanced significantly at a high absorbed dose. The irradiated sample at a dose of 100 kGy even couldn＇t be broken under the impact test load, and at the same time, has nearly no loss of tensile strength. Based on the analysis of the impact- fractured surface morphologies of the blends, it can be concluded that gamma-ray radiation at high absorbed dose can further in situ enhance the interfacial adhesion by promoting the crosslinking reactions of TMPTA and polymer chains. As a result, the toughness and strength of PET/ST2000 blend could be dramatically improved. This work provides a facial and practical way to the fabrication of polymer blends with high toughness and strength.展开更多
Daily exposure under solar ultraviolet(UV)and infrared(IR)is prone to cause skin cancer and photoaging.Real-time monitoring of the environmental UV index and IR radiation temperature during outdoor activities can enha...Daily exposure under solar ultraviolet(UV)and infrared(IR)is prone to cause skin cancer and photoaging.Real-time monitoring of the environmental UV index and IR radiation temperature during outdoor activities can enhance awareness and strengthen personal protection.It is a challenge to design flexible,wearable devices(with measurement capabilities)that can be integrated with apparels.Here,microfluidic spinning technology(MST)was used for the continuous and large-scale fabrication of eco-friendly coresheath Janus fibers with a well-defined axially symmetric Janus core.One side of the core was sensitive to UV light and the opposite was sensitive to IR radiation.Textiles woven with Janus fibers showed excellent independent reversible color responses to dual-wavelength stimulation.Such textiles switched among four colors under UV and IR irradiation,both individually and in combination.The color gradient of the textiles changed significantly with increasing UV intensity(UV index).After 60 cycles of UV/IR stimulation and 50 washes,the change rate of the comprehensive chromatic aberration(ΔE_(ab)^(*))of the textiles under different conditions was only 0.42%-4.71%.This was attributed to the unique structure of the fibers.The three-line striped textiles demonstrated the potential of the fibers to be used as wearable energy-free realtime visual monitors of the UV index and IR radiation temperature.展开更多
文摘Gamma-ray radiation has always been a convenient and effective way to modify the inter- facial properties in polymer blends. In this work, a small amount of trimethylolpropane triacrylate （TMPTA） was incorporated into poly（ethylene terephthalate） （PET）/random terpolymer elastomer （ST2000） blends by melt-blending. The existence of TMPTA would induce the crosslinking of PET and ST2000 molecular chains at high temperatures of blend- ing, resulting in the improvement in the impact strength but the loss in the tensile strength. When the PET/ST2000 blends were irradiated by gamma-ray radiation, the integrated me- chanical properties could be enhanced significantly at a high absorbed dose. The irradiated sample at a dose of 100 kGy even couldn＇t be broken under the impact test load, and at the same time, has nearly no loss of tensile strength. Based on the analysis of the impact- fractured surface morphologies of the blends, it can be concluded that gamma-ray radiation at high absorbed dose can further in situ enhance the interfacial adhesion by promoting the crosslinking reactions of TMPTA and polymer chains. As a result, the toughness and strength of PET/ST2000 blend could be dramatically improved. This work provides a facial and practical way to the fabrication of polymer blends with high toughness and strength.
基金supported by the Fundamental Research Funds for the Central Universities(2232019G-02 and2232019A3-02)Donghua University Distinguished Young Professor Program(LZB2019002)Shanghai Rising-Star Program(20QA1400300)。
文摘Daily exposure under solar ultraviolet(UV)and infrared(IR)is prone to cause skin cancer and photoaging.Real-time monitoring of the environmental UV index and IR radiation temperature during outdoor activities can enhance awareness and strengthen personal protection.It is a challenge to design flexible,wearable devices(with measurement capabilities)that can be integrated with apparels.Here,microfluidic spinning technology(MST)was used for the continuous and large-scale fabrication of eco-friendly coresheath Janus fibers with a well-defined axially symmetric Janus core.One side of the core was sensitive to UV light and the opposite was sensitive to IR radiation.Textiles woven with Janus fibers showed excellent independent reversible color responses to dual-wavelength stimulation.Such textiles switched among four colors under UV and IR irradiation,both individually and in combination.The color gradient of the textiles changed significantly with increasing UV intensity(UV index).After 60 cycles of UV/IR stimulation and 50 washes,the change rate of the comprehensive chromatic aberration(ΔE_(ab)^(*))of the textiles under different conditions was only 0.42%-4.71%.This was attributed to the unique structure of the fibers.The three-line striped textiles demonstrated the potential of the fibers to be used as wearable energy-free realtime visual monitors of the UV index and IR radiation temperature.
