This work deals with the in‐depth investigation of thiol‐yne based network formation and its effect on thermomechanical properties and impact strength. The results show that the bifunctional alkyne monomer di(but‐1‐yne‐4‐yl)carbonate ( DBC ) provides significantly lower cytotoxicity than the comparable acrylate, 1,4‐butanediol diacrylate ( BDA ). Real‐time near infrared photorheology measurements reveal that gel formation is shifted to higher conversions for DBC /thiol resins leading to lower shrinkage stress and higher overall monomer conversion than BDA . Glass transition temperature (Tg), shrinkage stress, as well as network density determined by double quantum solid state NMR, increase proportionally with the thiol functionality. Most importantly, highly cross‐linked DBC /dipentaerythritol hexa(3‐mercaptopropionate) networks (Tg ≈ 61 °C) provide a 5.3 times higher impact strength than BDA , which is explained by the unique network homogeneity of thiol‐yne photopolymers.
A double‐layer hollow fiber is fabricated where an isoporous surface of polystyrene‐block‐poly(4‐vinylpyridine) is fixed on a support layer by co‐extrusion. Due to the sulfonation of the support layer material, delamination of the two layers is suppressed without increasing the number of subsequent processing steps for isoporous composite membrane formation. Electron microscope‐energy‐dispersive X‐ray spectroscopy images unveil the existence of a high sulfur concentration in the interfacial region by which in‐process H‐bond formation between the layers is evidenced. For the very first time, our study reports a facile method to fabricate a sturdy isoporous double‐layer hollow fiber.
The development of asphalt‐based UV blocking materials is important to extend the alphalt lifespan in road construction. In this work, we put forward that the fabrication of host‐guest system can be an effective way to obtain UV blocking materials. Firstly, a new anionic Schiff base, N ,N' ‐bis(salicylidine)‐4,4'‐diaminostilbene‐2,2'‐disulfonic acid (SDSD ), has been synthesized, which was intercalated into Zn‐Al‐LDH by anion‐exchange method. FT‐IR and XRD illustrate the layered organic–inorganic composite, Zn‐Al‐SDSD‐LDH , has been successfully synthesized with high crystallinity. Laser particle size analyzer, SEM and TEM show that particle size distributions of Zn‐Al‐SDSD‐LDH is in the range 100–500 nm. UV –vis absorption spectra show that Zn‐Al‐SDSD‐LDH has better UV absorption than the pristine Zn‐Al‐LDH and SDSD . Furthermore, the mixture of asphalt and 3 wt% Zn‐Al‐SDSD‐LDH presents enhanced UV blocking property relative to the pristine asphalt after irradiating by UV spray accelerated weathering test. Therefore, this work not only develops a new type of host‐guest Zn‐Al‐SDSD‐ LDH , but also confirms it can be an effective asphalt UV blocking material for practical application. 相似文献