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Currently, the mechanical performance reduction caused by excessive phosphorus content in the halogen-free flame-retardant EP has been an obstacle to its extensive application. This study presents the effective synthesis of a novel flame-retardant BDD with great efficiency, achieving an optimum phosphorus level of merely 0.25 wt %. The structure of BDD was verified by FTIR, 1H NMR, 31P NMR and XPS spectra. To investigate the flame-retardant properties of BDD, several EPs with various phosphorus levels were synthesized. The addition of phosphorus to the EP significantly increases its LOI value from 25.8% to 33.4% at a phosphorus level of 0.25 wt%. Additionally, the resin achieves a V-0 grade in the UL 94 test. The P-HRR and THR of the modified resin measured by the cone calorimeter are also significantly reduced. At the same time, the addition of a modest quantity of BDD has a minimal impact on the mechanical properties of epoxy resin. This study shows that the removal of hydroxyl groups significantly enhances the fire resistance of phosphate-based flame retardants, thereby providing a novel approach to synthesizing efficient flame retardants. [ABSTRACT FROM AUTHOR]

Surface erosion of wind turbine blades, which are a key component of wind turbines, plays an important role in reducing the output power and service life of the blades. Rain erosion is also detrimental to wind turbine blades. In this review, the research progress on rain erosion is analyzed from the aspects of protection technology, rain erosion mechanism and related rain erosion tests and simulations. A comprehensive protective coating can be obtained by modifying or combining resins with different properties. Investigation of the rain erosion mechanism should consider the influence of the acidity of rain on the organic coatings. The rain erosion device should be more in line with the natural environment, and the dual structure of the substrate composite and surface coating of the blades should be fully considered as well in the rain erosion simulation. [ABSTRACT FROM AUTHOR]

A series of ultraviolet-curable hybrid materials was first synthesized here by sol-gel process based on tetraethoxysilane (TEOS) and polyurethane acrylate/epoxy acrylate resin. The functional groups in the hybrid materials were investigated by infrared spectroscopy (IR) analysis. The crystallinity of the hybrid materials and polymer resin was examined by X-ray diffraction. Then, nearly uniform dispersion of SiO2 particles with the diameters ˜100 nm were revealed by field emission scanning electron micrographs. The surface morphology was scanned by atomic force microscope. And, thermal stability was measured by thermogravimetric analysis for hybrid materials produced from different mass ratio of TEOS to polymer. The results show that the hybrid material from the mass ratio of TEOS to polymer of 0.4 : 1 performed desirable optimal thermal stability and uniform microstructure which is suitable for optical fiber coating in high temperature application. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]