Louis C. Muller^1*, Sanette Marx¹, Hermanus C.M. Vosloo²

Journal of Renewable Materials, Vol.5, No.1, pp. 67-80, 2017, DOI:10.7569/JRM.2016.634130

Abstract This work reports a study of polyol synthesis through liquefaction of technical lignins in crude glycerol by means of 1H and 31P NMR spectroscopy. The polyols are intended for preparation of polyurethane foam; thus, it is important to know how different lignin types as well as crude glycerol influence and contribute to the final polyol hydroxyl contents. Polyols prepared from organosolv lignin, kraft lignin and lignosulphonate had hydroxyl numbers suitable for rigid foam of 435, 515 and 529 mgKOH/g, respectively. The polyols differed in composition with glycerol, showing significant variation. During liquefaction the glycerol content More >

Galussi AA¹, JA Argüello², MM Cerana², M Maximino³, ME Moya¹

Phyton-International Journal of Experimental Botany, Vol.84, No.1, pp. 163-175, 2015, DOI:10.32604/phyton.2015.84.163

Abstract Seeds of alfalfa (Medicago sativa L.) can exhibit seedcoat imposed dormancy, which produces hard seeds within a seed lot. These seeds do not germinate because they do not imbibe water due to a barrier to water entry in the seed coat. The aim of this work was to analyze the anatomical and chemical characteristics of the testa of alfalfa seeds with respect to water permeability levels. The anatomy of seeds of the cv. Baralfa 85 was studied and structural substances, polyphenols, tannins and cutin present in the testa of seeds of different water permeability levels were… More >

Antti Ojala^1,*, Lisa Wikström¹, Kalle Nättinen², Jani Lehmonen³, Karita Kinnunen-Raudaskoski⁴

Journal of Renewable Materials, Vol.2, No.4, pp. 278-284, 2014, DOI:10.7569/JRM.2014.634126

Abstract This article presents a new method of producing thermomoldable nonwoven materials based on kraft lignin (KL) and softwood kraft pulp (KP). A mixture of starch acetate (SA) and triethyl citrate (TEC) was used as a water insoluble plasticizer for KL. The thermoplastic lignin (TPL) material with the optimized ratio of KL, SA and TEC was prepared in a twin-screw extruder. The TPL compound was ground and mixed with KP fi bers to produce thermoformable sheets using foam-laid technology. The formed webs were compression molded (CM) into plates and mechanically tested. The foam-laid composites had tensile More >

Sinto Jacob¹, Manjusri Misra^1,2, Amar Mohanty^1,2,*

Journal of Renewable Materials, Vol.1, No.2, pp. 154-165, 2013, DOI:10.7569/JRM.2012.634107

Abstract This study investigated the use of potassium persulfate (KPS) as an initiator for the grafting of methyl methacrylate (MMA) onto softwood kraft lignin. Ammonium iron (II) sulfate hexahydrate was used as a catalyst to overcome the inherent inhibition of lignin to free radical grafting and to make lignin copolymer under mild conditions using an aqueous medium. The infl uence of temperature, initiator concentration, time of reaction and monomer concentration on percentage of grafting were studied. A maximum of 31% grafting was achieved at 55ο C. Graft copolymer was identifi ed from the Fourier transform infrared More >

Hyoe Hatakeyama^1,*, Tatsuko Hatakeyama²

Journal of Renewable Materials, Vol.1, No.2, pp. 113-123, 2013, DOI:10.7569/JRM.2012.634111

Abstract Lignin and saccharides are two major components of plants. Huge amounts of plant residues are obtained as by-products of large-scale industries, such as pulp and paper, bio-fuel and the food industry. In this paper, preparation of polyurethane (PU) foam directly from various kinds of industrial lignin and molasses, which have scarcely been utilized, is summarized based on our results obtained by recent investigation. A onestep reaction using hydroxyl groups of plant materials as an active site makes it possible to produce a wide variety of PU, such as foams, sheets, gels and composite matrix. In More >