Papers by Keyword: Internal Bond

Abstract: The physical (density and moisture content) and chemical properties of the oil palm trunk (OPT) were examined. The effect of different densities (500, 600, and 700 kgm^-3) and different percentages of urea-formaldehyde (UF) resin content (8, 10, and 12%) on the single layer at the different portions of OPT particleboard were evaluated for mechanical and dimensional stability. The results showed that the bottom portion and near bark had a positive result on density and moisture content. Lignin, holocellulose, and alpha-cellulose of the OPT showed the highest content at the bottom portion. The density was found to effect all the board properties significantly at p < 0.05 on the modulus of elasticity (MOE), modulus of rupture (MOR), internal bond (IB), thickness swelling (TS), and water absorption (WA) of the particleboards. For the resin content, all the board properties were effected except for the water absorption. The particleboards produced, from 700 kgm^-3 densities and 10% resin content, met the minimum requirement for the particleboard (Type 18) stipulated in the Japanese Industrial Standard (JIS A 5908). The particleboard manufacturing from OPT particles as the replacement for wood is very promising.

Abstract: With the continuous development of printing technology and printing equipments, the quality of newsprint should be improved to meet with all the real demands. Acrylamide copolymer is used in paper-making as process aid and function aid which can effectively improve paper printing adaptability. Preparation and application of polyacrylamide via aqueous copolymerization was studied as dry strength agent in this paper. The polyacrylamide with middle molecular weight and low viscosity was obtained by reacting acrylamide, cationic monomer [2-(acryloyloxy)ethy] -trimethylammonium chloride and N,N-dimethylaminoethyl methacrylate, anionic monomer itaconic acid, active nonionic monomer N-metholacrylamide and crosslinking monomer 1,3,5-triacryloylhexahydro-s-rine, the copolymer was characterized by FT-IR, charge density and molecular weight distribution. On the basis of internal present situation of pulp, the papermaking system with deinking pulp from office waste paper and white water of 1000-1200us/cm conductivity from paper mill were selected for application research. The results show that when the dosage of acrylamide copolymer is 0.8% to the dry weight of pulp and handsheet basis weight is 60g/m2, acrylamide copolymer can show the superior performance to newsprint and receivable cost for paper mill, fluffing speed, tearing strength and internal bonds are respectively improved by 14%, 20% and 30%.

Abstract: The purpose of this study was to determine the effect of particle size on the mechanical properties (Modulus of Elasticity, Modulus of Rupture, and Internal Bond) and physical properties (thickness swelling and water absorption) of rice husk particleboard. The particle sizes used were 1.0mm, 1.18mm, 2mm, 2.36mm and 2.80mm. Each was mixed with a constant resin (urea formaldehyde) concentration of 20% of oven dry weight of rice husk particles. The results showed that as the particle size increased, the particleboard’s mechanical and physical properties decreased. For example, the modulus of elasticity, modulus of rupture, internal bond, thickness swelling and water absorption for 1.0mm particle size particleboard were 1590N/mm2, 11.11N/mm2, 0.28N/mm2,10.90% and 38.53% respectively, while for 2.8mm particle size they were 1958N/mm2,14.2N/mm2, 0.44N/mm2, 11.51% and 47.21% respectively. Overall results showed that particleboard made from rice husk exceed the EN standard for modulus of elasticity, modulus of rupture, internal bond. However, thickness swelling values were poor. Hence, the smaller the particle size the better the properties of the particleboard.