Browsing by Author "Fuwape, J. A."

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Effect of shelling ratios on the sorption and flexural properties of cement bonded particleboard produced from mixed Nigerian hardwood species
(Forest and Forest Products Society, 2014) Badejo, S. O.; Omole, A. O.; Fuwape, J. A.
Panel layer characteristics, otherwise referred to as shelling ratio, relate to the proportional ratio between the thickness of the fine surface layer and flake core layer materials in a 3-layered particleboard. The experiment was carried out in order to determine the most favourable core-surface thickness ratio at which board properties are maximized. To achieve this, experimental cement-bonded particleboards were made using three sawdust surface/flake core layer thickness ratios d 1 : 2, 1 : 1 and 2 : 1. Each of the ratio was considered at two board density IeveIs of 1100 and 1200 kg/m3 and two cement/wood mixing ratio of 2.25 : 1.0 and 2.75: 1.0. The experimental arrangement is a three-factor factorial experiment which manifested in 12 treatment combinations. The experimental boards produced were subjected to modulus of rupture (MOR), modulus oSf elasticity (MOE), water absorption (WA), thickness swelling (TS) and linear expansion (LE) tests. Data collected were subjected to statistical analysis using ANOVA and multiple linear regressions. The mean Moduli of Rupture and Elasticity (MOR and MOE) obtained ranged from 4.23 to 11.92 N/mm2 and 1950 to 4140 N/mm2 respectively. Water absorption (WA) and thickness swelling (TS) ranged from 24.75 to 10.58% (WA) a d 0.41 to 4.01% (TS). It noted that the mean values of MOR and MOE obtained at the sawdust surface layer/flake core layer thickness ratio of 1 : 2 were significantly superior at 5% level of probability to those obtained at the thickness ratio levels of 1 : 1 and 21.1. On the other hand however, the mean values of WA and TS obtained at the sawdust surface layer/flake core layer thickness ratio of 2 : 1 were significantly superior at 5% level of probability to those obtained at thickness ratio levels of 1 : 2 and 1 : 1. of sawdust to flake contents of board. The highest strength and stiffness values obtained at the thickness ratio level of 1 : 2 of sawdust surface layer flake core layer notwithstanding, the thickness ratio level of 2 :1, which implies cement-bonded particleboard production at increased sawdust content and decreased flake content, was selected applied as a the optimum. This being so, in view of the fact that the overriding objective of the study was to 6 mm thick cement-bonded particleboards which could be resistant to moisture and adequate for house ceiling.
Physical and mechanical properties of cement-bonded particleboards produced at different water pre-treatment temperatures and cement/wood mixing ratios
(Forest and Forest Products Society, 2011) Badejo, S.O.; Omole, A. O.; Fuwape, J. A.; Oyeleye, B. O.
The influences of water pre-treatment temperature and cement/wood mixing ratios on static and moisture response properties of cement-bonded particleboards produced from mixed Nigerian hardwood species were assessed in this study. The process variables for board fabrication were pre-treatment temperature (5 levels) and wood/ cement mixing ratios (5 levels) resulting in 25 treatment combinations in a factorial experiment. The examined properties are modulus of rupture (MOR), modulus of elasticity (MOE), water absorption (WA), thickness swelling (TS) and linear expansion (LE) properties of the experimental cement-bonded particleboards. Data collected were analysed using a combination of ANOVA and multiple linear regression models. Mean MOR and MOE ranged from 4.02 to 12.74 N/mm2 and 2040 to 4060N/mm2 respectively, while (WA), (TS) and (LE) ranged from 27.13 to 43.97%, 0.51 to 3.50% and 0.14 to 0.72% respectively. Strength (MOR) and stifness (MOE) of the boards increased as water pre-treatment temperature were raised from 35°C to 80°C. As water pre-treatment temperature was raised from 80°C to 95°C, weaker and inferior boards were produced. Water pre-treatment temperature was weakly correlated with MOR, MOE, WA, TS and LE. On the other hand, cement/wood mixing ratio was well correlated with these board properties. The study thus demonstrated that there is optimum water pretreatment temperature range (65°C-80°C) within which high quality boards can be produced in the selected species; and beyond which board quality will be impaired.
Static bending and moisture response of cement-bonded particleboard produced at different levels of percent chemical additive content in board
(Faculty of Agriculture, University of Uyo, Nigeria, 2012) Badejo, S.O.; Omole, A. O.; Fuwape, J. A.; Oyeleye, B. O.
A study was carried out to determine the optima level of percent additive concentration for wood cement board production from mixed tropical hardwoods species. Eight hardwood species used for the study are: Triplochiton scleroxylon K. Schum (Obeche). Terminalia ivorensis A. Chev. (Idigbo) Terminalia superb Eng. & Diets (Afara) Bruchystegia nigerica Hoyle & A.P.D. Jones (Okwen) Khaya ivorensis A. Chev. (Lagos Mahogany) Nesogordonia papaverifeni A. Chev. (Dantu-Oro) Tectona grandis Linn. F. (Teak) Gmelina arborea Roxb. (Gmelina). The experimental boards were made at five chemical additive content levels of 1.00%: 1.50%: 2.00%: 2.50% and 3.00% based on dry weight of cement in board, and three cement/wood mixing ratio levels of 2.25: 1.0. 2.50: 1.0 and 2.75:1.0. The experimental design is a two-factor factorial experiment, a combination of which manifested in 15 treatment combinations. The mean moduli of Rupture and Elasticity (MOR and MOE) obtained for each of the 15 treatment combinations in this experiment ranged from 3.28 to 10.46 N/mm2 while MOE values ranged from 2200 to 4010 N/mm2. The mean percent water absorption (WA) values ranged from 24.66 to 46.37% while the thickness swelling (TS) ranged from 0.98 to 3.62%. Statistical analysis showed chemical additive concentration and wood/cement ratio were found significant at 1% level of probability on the flexural and moisture properties. Stronger, stiffer and more dimensionally stable boards were produced at increasing levels of these two production variables. Also percent chemical additive content in board of 3.0% (Based on dry cement weight in board) performed best.