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ABSTRACT For the past decade, the interest in controlled grafting of cellulose has increased immensely. Surface-Initiated Atom Transfer Radical Polymerization (SI-ATRP) has attracted the most interest; however, the sensitivity of this system has so far hindered its utilization in industry. In this study, filter paper, dissolving pulp, bleached and unbleached Kraft-pulp, and chemi-thermomechanical pulp papers were grafted with methyl methacrylate, employing activators regenerated by electron transfer (ARGET) ATRP. The reactions were performed in bulk or with small amounts of aqueous solutions, with no deoxygenation performed. To further demonstrate the robustness of this method towards simpler and more industry-friendly processes, the polymerizations were conducted in glass jars with screw lids. The possibility of recycling the reaction solution was also explored. We believe his thorough study to be an important step towards industrializing the 'grafting-from' concept, and the results herein can most likely be extended to other surfaces and monomers. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41434. [ABSTRACT FROM AUTHOR]

Plant proteins, such as wheat gluten, constitute attractive raw materials for sustainable wood adhesives. In this study, alkaline water dispersions of the protein classes of wheat gluten, glutenin, and gliadin were used as adhesives to bond together wood substrates of beech. The aim of the study is to measure the tensile shear strength of the wood substrates to compare the adhesive performance of glutenin and gliadin and to investigate the influence of application method and penetration of the dispersions into the wood material. A sodium hydroxide solution (0.1 M) was used as dispersing and denaturing agent. Dispersions with different protein concentrations and viscosities were used, employing wheat gluten dispersions as references. Two different application methods, a press temperature of 110°C and a press time of 15 min, were employed. The tensile shear strength and water resistance of the wood substrates were compared, using a slightly modified version of the European Standard EN 204. The bond lines of the substrates were examined by optical microscopy to study the penetration and bond-line thickness. The results reveal that the adhesive properties of gliadin are inferior to that of both glutenin and wheat gluten, especially in terms of water resistance. However, the tensile shear strength and the water resistance of gliadin are significantly improved when over-penetration of the protein into the wood material is avoided, rendering the adhesive performance of gliadin equal to that of glutenin and wheat gluten. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]