Preparation and Characteration of UV-cured EA/MMT Nanocomposites Via In-Situ Polymerization

A long-chain surfactant, enzoylbenzyl-N,N-dimethyl-N-octadecylammonium bromide (BDOB) with a benzophenone group, was synthesized to modify the montmorillonites (MMT) for the preparation of nanocomposites via photo-induced polymerization. The BDOB-modified MMT was characterized by the fourier transform infrared spectrometer (FTIR), thermal gravimetric analyzer (TGA) and X-ray diffraction (XRD), and the results of XRD indicated that the intercalated structures of BDOB-modified MMT was obtained. The conversion of the bisphenol A epoxy diacrylate (EA) was quantified by the FTIR, and the results indicated that conversion increased with an increase in the amount of BDOB-modified MMT. The morphologies of the UV-cured EA/MMT nanocomposites prepared from this organically modified MMT were studied by means of XRD and TEM, and the results showed that all the samples contained an intercalated structure with partial exfoliated structure. The results of TGA and mechanical properties also indicated that the thermal and mechanical properties of UV-cured nanocomposites were significantly enhanced due to the presence of the long chain surfactant organically modified MMT.     

UV-cured hyperbranched polyester polythiol(H20-SH)-epoxy acrylate networks: Preparation,thermal and mechanical properties

A hyperbranched polyester polythiol(H20-SH) was synthesized and characterized by FTIR spectral analysis, ¹H-NMR spectral analysis and GPC analysis. H20-SH was added into the formulation of UV-curable epoxy acrylate networks based on thiol-acrylate chemistry. The effects of H20-SH on polymerization kinetics, thermal and mechanical properties of thiol-epoxy acrylate networks were investigated by Real-time infrared spectroscopy, dynamic mechanical analysis (DMA), thermogravimetric (TGA), tensile test and water absorption characterization. Results show that epoxy acrylate resin with the addition of H20-SH massively reduces oxygen inhibition, improves the uniformity of cured films and enhances the tensile strength of the films. However, the thermal stability and glass transition temperature (T_g) decreases with the increasing amount of H20-SH.     

Highly cross-linked UV-cured siloxane copolymer networks as icephobic coatings

Preventing ice growth on infrastructure, vehicles, and appliances remains a significant engineering challenge. Damage caused by ice growth on these installations can be expensive to repair, and their failure can be dangerous. Materials such as cross-linked polymer networks make effective anti-ice coatings and can prevent ice growth: reducing the cost of infrastructure repairs and limiting downtime. A link between cross-link density and ice adhesion has been demonstrated, such that lower cross-link density materials tend toward lower ice adhesion. Here we describe a method of lowering cross-link density by incorporating the covalently bound comonomers methyl methacrylate, lauryl methacrylate, and styrene into UV-cured PDMS-based polymer networks. Cross-link density, hardness, surface roughness, and ice adhesion on these materials are tested, showing the influence of comonomer proportions on their properties. Durability is found to increase with the addition of 5, 10, and 25 wt% comonomer, with little to no effect on ice adhesion until 25 wt%, where increases in ice adhesion are observed. Coatings show promisingly low ice adhesion of ~50 kPa, maintaining this low adhesion for up to 50 deicing cycles.     

紫外光固化油墨中的颜料分散

１引言九十年代以来,印刷油墨行业受到来自环境保护的压力越来越大。辐射固化油墨（其中ＵＶ固化占９０％）的研究和应用出现了日新月异、迅猛发展的良好势头。紫外光固化油墨较之传统油墨固化迅速、能耗低,可用于对热敏感的基材,固化产品性能优越,最重要的是无溶剂挥发造成的环境污染,是面向二十一世纪的绿色工业技术！”。紫外光固化油墨中的颜料分散与传统油墨类似,但油墨本身成本高低与组分及其配比关系极大,其中如何选择颜料、分散助剂,如何调整分散工艺是控制成本的关键技术。１．１影响颜料分散的因素油墨中颜料分散的情况,…     

Synthesis and Characterization of Novel UV-curable Fluorinated Polyurethane-acrylate Copolymer

A series of UV-curable fluorinated polyurethane-acrylate(PUA) has been developed by incorporating octafluoropentyl alcohol into the segment of UV-curable polyurethane-acrylate to improve the thermal property and surface property of the copolymer material. The structures of the synthesized polymers were characterized by Fourier transform infrared(FTIR) spectrometry. In order to find out the effect of incorporated fluorine on the UV-cured films, the properties of the UV-cured films were tested through contact angle, water absorption, and thermogravimetric analysis (TGA). The fractured-surface morphologies of the UV-cured coatings were investigated by scanning electron microscopy(SEM). With increasing the content of fluorine segments, the contact angle of the UV-cured films increased and the water absorption decreased, suggesting the fluorine segments migrated and formed a fluorine-covered surface to avoid water penetration. The observation of the fractured-surface morphology through SEM test showed that the fluorinated UV-cured films gained rough fractured-surface compared with the pure UV-cured polyacrylate film, demonstrating the migrating of the fluorine segments. The TGA curves show that the fluorinated UV-cured films gained higher thermal degradation temperature than the virgin UV-cured polyacrylate film. And as increasing the fluorine content, the thermal degradation temperature increased. These phenomena could be reasonably explained by the enrichment of fluorinecontained segment on the surface of the film and the high thermal property due to fluorine atom.