Springer, Wood Science And Technology

 Journal

 Mechanical Behavior Of Chemically Modified Norway Spruce: A Generic Hierarchical Model For Wood Modifications

 Mora Mendez, D.F., Olaniran, S.O., Rüggeberg, M., Burgert, I., Herrmann, H.J., Wittel, F.K.

 2019

Modifications alter hygro-mechanical properties of wood in non-trivial ways that depend on modification treatment and wood microstructure. Generic micromechanical models with modifications on the cellular scale of spruce are proposed and studied, such as partial and entire lumen filling with isotropic materials, as well as modification of S2-layer properties. Based on a hierarchical micromechanical model, hygro-mechanical response surfaces of the modified, orthotropic material are predicted. Simulation results are compared to experimental data. The findings can be used for optimizing modification treatments, as well as for calculating the behavior in graded situations, common to treatments with limited modification depth. 

 Springer, Wood Science And Technology

 Journal

 Mechanical Behaviour Of Chemically Modified Norway Spruce (Picea Abies L. Karst.): Experimental Mechanical Studies On Spruce Wood After Methacrylation And In Situ Polymerization Of Styrene

 Samuel OlOlaniran, S.O., Michen, B., Mora-Mendez, D.F., Wittel, F.K., Bachtiar, E.V., Burgert, I., And Rüggeberg, M.

 2019

Chemical modification of wood mainly aims at improving dimensional stability, resistance to biodeterioration and surface degradation. In some cases, it is specifically targeted at adapting or improving mechanical performance. However, a general understanding of the effects of chemical modification on the mechanical properties of wood, which would facilitate more efficient modification strategies, is missing. Here, a combined experimental and simulation study is provided to gain a more general understanding of the mechanical behaviour of chemically modified wood. In the first part of this study, the mechanical properties of chemically modified Norway spruce are studied experimentally. In Mora Mendez et al. (Wood Sci Technol 2019), simulations of different types of chemical modifications will be presented using a multi-scale model and the outcome will be compared with the obtained experimental data. Chemical modification was based on a two-step modification process. The first step involved methacrylation of the OH-groups in the cell wall. In the second step, in situ polymerization of styrene was induced in the methacrylated samples, which resulted in a partial cell wall and lumen filling. Tensile stiffness and rolling shear stiffness were analysed for methacrylated and polymerized samples. Whereas only small changes in mechanical properties were found for methacrylated samples, the polymerization process led to pronounced increases in elastic modulus and shear stiffness because of weight percent gains of 60–95%. Yet, the specific stiffness was lowered, as the density increase was disproportionate to the stiffness increase. Moreover, a pronounced improvement in rolling shear modulus (GRT) by a factor of 4.5 was obtained for the in situ polymerized specimen. 

 Applied Tropical Agriculture

 Journal

 Evaluation Of Thermal Conductivity Property Of Selected Wood Species In The Steculiaceae Family

 Olufemi, B., Olaniran, S.O., Olonisakin, K.S., Adedeji, E.T., And Bello, O.R.

 2017

Thermal conductivity of Pterigota macrocarpa, Triplochiton schleroxylon and Nesogodonia papaverifera, all in the Steculiacea family was investigated. Samples of 50 mm by 50 mm were collected from the sawmill and turned into cylindrical form using the wood turning lathe machine with each sample having a radius of 20 mm and a thickness of 5 mm. The samples were placed between discs A and B of the modified Lee disc machine one after the other while the electrical plate was placed between disc B and C of the apparatus respectively and the thermal conductivity values for each sample taken while the temperature was monitored. The results showed that Nesogodonia papaverifera exhibited the lowest thermal conductivity with a mean of 0.22 Wm-1k-1followed by Pterigota macrocarpa and Triplochiton schleroxylon having a mean conductivity of 0.25 Wm-1k-1 and 0.27 Wm-1k-1 respectively. Also at hot rising and falling temperatures, Pterigota macrocarpa and Nesogodonia papaverifera exhibited highest and lowest thermal agitations at 0.32Wm-1k-1.The selected wood samples in the Steculiacea family possessed good thermal conductivity when compared with other wood species that their conductivity has been studied. 

 Trade Science Incorporated

 Journal

 Effect Of Thermal And Chemical Modifications On The Dimensional Stability Of Triplochiton Scleroxylon (Obeche) Wood

 Idowu, A., Olaniran, S.O., Fabiyi, J.S., And Oluyege, A.O.

 2015

This study examined the dimensional stability of thermal and chemically modified Triplochiton scleroxylon (Obeche) wood. Sample planks were obtained from a local sawmill and converted to produce defect free samples of dimensions of 20 mm × 20 mm × 10 mm. wood samples were oven-dried at 105°C and cooled in a desiccator to a constant weight before the treatments. Heat treatments of samples were carried out in a Muffle furnace at 160 and 200°C for 30, 60 and 120 min. Butyl acetate was used for chemical treatment. The test samples were analyzed with Fourier Transform Infrared Spectroscopy (FTIR). Dimensional stability of the test samples and untreated (control) were measured with parameters such as anti-swelling efficiency (ASE), volumetric swelling (S), and water absorption (WA). Results showed that WA and S values decreased with increase in temperature and treatment time. At a treatment time of 120 minutes, compared with the control, lower values of 11.18 % and 9.23 % were obtained for WA at 160 and 200°C respectively. Volumetric swelling values of 7.31% and 6.06% were obtained at the same temperature and treatment time. Anti-swelling efficiency values also increased with increase in temperature and treatment time. Chemical treatment with butyl acetate produced the highest ASE of 70.41%. These results indicate that the sorption properties of T. scleroxylon wood were reduced as a result of the thermal and chemical modification treatments. Thus, it can be inferred that the treated wood will exhibit a measure of resistance to problems such as bio-deterioration and dimensional instability following ingress of water during use. 

 Applied Tropical Agriculture

 Journal

 Flexural Strength Of Incised Rubber-Wood (Hevea Brasiliensis Muel. Arg.) Treated With Creosote Oil And Liquefied Biomass

 Olaniran, S.O., And Olufemi, B.

 2015

The influence of incision and chemical treatments on the flexural strength of Hevea brasiliensis (Rubber-wood) was examined. Clear samples of dimension 20mm × 20mm × 300mm were prepared and selected as specified in American Standards for Testing Materials (ASTM) standards. Incision was done with a mechanical incisor at a length and depth 7mm and 3mm respectively. Three levels of incision densities (666.6, 1000 and 2 0 1333 incisions/m ) were used. Test samples were oven-dried at 103±2 C for 24 hr. untreated samples, serving as the control, were maintained at 12 % moisture content. Creosote oil and liquefied biomass were used as preservatives to treat the wood samples using the cold-soaking method. Parameters such as absorption and retention were measured. Flexural strength; modulus of rupture (MOR) and modulus of elasticity (MOE) of the wood samples were tested on Housefield Tensiometer. Results showed that rubber-wood treated with creosote oil had a mean absorption and 3 retention of 29.94 %, and 1.22 Kg/m respectively while the liquefied biomass treated samples had 58.61 % and 2.38 Kg/m3 for absorption and retention respectively. Incision had a significant effect (p0.05) on absorption and retention of rubber-wood. However, greater losses in strength 2 2 resulted from combining incision with the preservative chemicals. Higher strength loss in MOE (6847.12 N/mm ) and MOR (57.76 N/mm ) 2 2 ensued with the use of liquefied biomass compared with creosote oil with 8703.46 N/mm and 83.25 N/mm for MOE and MOR respectively. This is an indication that rubber-wood has a higher absorption and retention of waterborne preservatives (liquefied biomass) but lower values for creosote oil. However, its strength properties were highly affected with the use of liquefied biomass preservative. 

 International Journal Of Biological Sciences And Applications, USA

 Journal

 Natural Resistance Of Ten Selected Nigerian Wood Species To Subterranean Termites Attack

 Owoyemi, J.M And Olaniran, O.S

 2014

NILL 

 Forests And Forest Products Society, Nigeria

 Conference

 Bio-deterioration Issues In The Sustainability Of Wood And Wood Products

 Olaniran, O.S., Olufemi, B., And Owoyemi, J.M.

 2014

This paper discusses the bio-deterioration of wood and issues relating to sustainability of wood products through treatments that makes wood unattractive to bio-deteriorating agents. Wood components and properties that predisposes wood to attack of bio-agents most importantly the affinity of wood for moisture as a result of the presence of hydroxyl groups. Issues bothering on the effects of moisture on bio-deterioration and sustainability of wood and wood products supply were mentioned. Measures to ensure protection of wood from bio-deterioration including control of moisture content, use of naturally resistant wood and use of conventional preservatives was stated. Emphases were made on the need to develop wood modification processes to produce treated wood products that will be environmentally friendly and reduce the effect of conventional preservatives on human health, soil micro-organisms and climatic change. Individual roles in ensuring that wood structures are designed with durability mindset were stated. 

 Proligno Journal

 Journal

 Effect Of Density On The Natural Resistance Of Selected Indigenous Species To Subterranean Termites

 Owoyemi, J.M, Olaniran, O.S. And Aliyu, D.

 2013

NILL 

 Unpublished

 Disertations

 Effects Of Chemical Preservatives And Incision On The Strength And Durability Of Hevea Brasiliensis And Pterocarpus Milbraedii Wood. M. Agric. Tech. Thesis. Department Of Forestry And Wood Technology, Federal University Of University Of Technology, Akure.

 Olaniran, O.S

 2012

N/A

 

 Drvna Industrija

 Journal

 Lumber Recovery Efficiency Among Selected Sawmills In Akure, Nigeria

 Olufemi, B., Akindeni, O.J., And Olaniran, O.S.

 2012

NILL