Fire retardants may considerably improve the 5re properties of wood products, but the durability, e.g. in exterior applications, has not been addressed fully. This paper reviews the existing knowledge and experience mainly from the USA with the aim of supporting further development in Europe. The review is concentrated on pressure impregnated 5re retardant treated wood products which have the best opportunities for increased durability.

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A polyurea macromer (PUM) was synthesized and dispersed in basic conditions to form self‐assembled nanoparticles (<20 nm dispersions, up to 30 wt % aq. soln.). These nanoparticles enabled surfactant‐free emulsion polymerization to form hybrid polyurea‐acrylic particles despite the absence of a measureable water‐soluble fraction. The Tg of the starting PUM material was a strong function of the PUM's extent of neutralization and hydration (varying between 100 °C and >175 °C) due to changes in hydrogen and ionic bonding. Two separate hybrid polyurea‐acrylic emulsion systems were prepared: one by direct polymerization of (meth)acrylic monomers in the presence of the nanodispersion and a second by a physical blend of PUM nanodispersion with an acrylic latex control. The direct polymerization method resulted in a hybrid emulsion particle size that developed by a mechanism resembling conventional emulsion polymerization and was unlike that described for seeded polyurethane dispersion systems. Film hardness was shown to increase with increasing coating thickness for the hybrid film prepared by direct polymerization. The resulting mechanical properties could be explained by applying mechanical models for a composite foam structure. These results were unprecedented for normal elastomer films. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1373–1388

For the current commercialized agricultural industry which requires a reduced product lead time to customer and supply all year round, an artificial light emitting diode (LED)-based illumination has high potential due to high efficiency of electrical-to-light conversion. The main advantage of the deployed Red Green Blue Amber LED lighting system is colour mixing capability, which means the ability to generate all the colours in the spectrum by using three or four primary colour LEDs. The accelerated plant growth was carried out in a "light-box" which was made to generate an artificial day/night cycle and had a capability to tune the colour mixing ratio along the colour temperature curve of the chromaticity diagram. The control group of plants form the same initial batch was grown on the same shelf in a greenhouse at the same conditions with addition of artificial illumination by incandescent lamps for few hours. More dense and better quality (hence, commercial value) plants were grown in the light-box. Costs and efficiency projections of LED lamps for horticultural applications is discussed together with required capital investment. The total cost of the "light-box" including LED lamps and electronics was 850 AUD.

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