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Vol 19, No 4 (2017) Ahead of Print by Olufemi Adefisan

The feasibility of using rattan canes (Laccosperma secundiflorum and Eremospatha macrocarpa) as r... more The feasibility of using rattan canes (Laccosperma secundiflorum and Eremospatha macrocarpa) as reinforced fillers for high density polyethylene based plastic composite production was investigated. Extruded composites were tested for water sorption, tensile and thermal properties. The results obtained indicated that the rattan composites were dimensionally (water absorption: 2.2 - 21.4%; thickness swell: 0.9 – 5.3%) and thermally stable (Tc: 116.8 – 118.2ₒC) and possessed adequate tensile properties (7.3 – 21.7MPa). Composites made from L. secundiflorum had higher strength and thermal properties but lower sorption values compared to those of E. macrocarpa. Differences in the densities of the composites and the anatomical structures of the rattans seemed to influence properties of the composites.

Papers by Olufemi Adefisan

Journal of Applied Science, Engineering and Technology, Sep 15, 2021

Bio plastics produced from cassava starch plasticised with glycerol and sorbitol and reinforced w... more Bio plastics produced from cassava starch plasticised with glycerol and sorbitol and reinforced with Gmelina arborea wood fibres at 0 20% fibre contents, 212 and 650 µm fibre sizes were test ed for strength properties. The results obtained revealed that the bio composites had strength properties: tensile strength (0.13 3.34MPa), moduli (1.99 36.31MPa), extension at break (7.08 18.85 mm) comparable with those previously reported in literat ure. Fibre size significantly affected the tensile strength while fibre content significantly affected the moduli and extension at break of the bio composites. Biocomposites produced with sorbitol had significantly higher tensile strength, moduli and exten sion at break than those produced with glycero

Journal of Tropical Forest Science, 2012

ADEFISAN OO, IDRIS A & OJEABULU J. 2012. Effects of particle size, composite mix and cold water t... more ADEFISAN OO, IDRIS A & OJEABULU J. 2012. Effects of particle size, composite mix and cold water treatment on the compressive strength of Eremospatha macrocarpa-cement composite. Rattan-cement composites were manufactured using different particle sizes (0.60,0.85 and 1.18 mm) of un treated Eremospatha macrocarpa cane and those treated in cold water using cement-sand ratio of 1:3 and 10% of rattan based on the cement mass. Specimens were tested for compressive strength after 28 days of curing. Increasing the particle size and inclusion of sand in the composite mix reduced the compressive strength while pre-treatment with cold water enhanced the compressive strength. The compressive strength of E. marcocarpa-cement composites was influenced by the interactions of pre-treatment and particle size as well as pre-treatment, particle size and composite mix.

Journal of Tropical Forest Science, 2011

simen. Kesesuaian rotan Eremospatha macrocarpa yang tidak dirawat dalam penghasilan komposit beri... more simen. Kesesuaian rotan Eremospatha macrocarpa yang tidak dirawat dalam penghasilan komposit berikatan simen (CBC) dan kesan rawatan air sejuk terhadap keserasian spesies ini dengan simen dikaji menggunakan pendekatan ujian penghidratan. Partikel E. macrocarpa dicampur dengan simen dan air serta dimasukkan ke dalam kelalang termo yang ditebat. Kenaikan suhu diawasi selama 24 jam. Kesesuaian spesies dalam penghasilan CBC dinilai berdasarkan tempoh pensetan (t max ), suhu penghidratan maksimum (T max ) dan nisbah masa (t R ). Nilai-nilai t max , T max dan t R bagi komposit simen masing-masing berjulat dari 7.2 jam–8.5 jam, 55.0 o C–57.1 o C dan 1.2–1.4. Rawatan dengan air sejuk mengurangkan t max , T max dan t R komposit simen masing-masing sebanyak 15.3%, 3.7% and 14.3%. Rawatan air sejuk menjadikan partikel E. macrocarpa yang tidak dirawat sesuai diguna bersama-sama simen.

International Journal of Composite Materials, 2016

The feasibility of developing non-conventional composite tiles using fibres extracted from Cissus... more The feasibility of developing non-conventional composite tiles using fibres extracted from Cissus populnea was investigated. C. populnea stems were sourced from a local market in Ibadan, processed and used for cement composites tile production. A manually-operated tile making machine was designed and constructed. The machine was able to produce 50-pieces of 200x100x10.5 mm of composite-tiles per hour. The tiles were conditioned and tested for dimensional stability and mechanical properties in accordance with ASTM D 1037-00. Results obtained indicated that the tiles were dimensionally stable with low sorption and swelling rates but had moderate strength suitable as insulating components such as wall and floor tiles. Pre-treatment with calcium chloride significantly enhanced the dimensional stability but reduced the strength properties.

Arid Zone Journal of Engineering, Technology and Environment, 2021

The excessive reliance on plastic materials made from fossil-fuel based and its ineffective waste... more The excessive reliance on plastic materials made from fossil-fuel based and its ineffective waste management leads to environmental pollution due to their non-biodegradable nature. This study examined the production and testing of bio-composites from Gmelina Arborea wastes and thermoplastic starches as a polymer matrix. Particles of G. Arborea sawdust were obtained from a local sawmill while dry powdered corn starches were sourced from the chemicals market, Ojota, Lagos, Nigeria. Bio-composites were produced by mixing 40 g of corn starch, glycerol/sorbitol, and fractions of prepared G. Arborea (650µm particle sizes) fibre at 0 to 20% (wt/wt of fibre to polymer matrix) were added. The slurries were poured into a mould in accordance with ASTM D638 for tensile strength test samples. The results revealed that the thermoplastic starches, particle sizes, plasticizers, and wood fibre loading significantly affected the tensile strengths, tensile modulus, elongation at break of the bio-compo...

Journal of Applied Science, Engineering and Technology, 2009

This study investigated the effects of wood-cement ratio, calcium chloride ( CaCl 2 ) addition (0... more This study investigated the effects of wood-cement ratio, calcium chloride ( CaCl 2 ) addition (0-3%) and cold water extraction on strength and sorption properties of cementbonded composites produced from eucalyptus (Eucalyptus tereticornis Sm.) veneer waste. Hammer-milled particles were characterized and used. Boards measuring 150 x 150 mm were manufactured in a low pressure system at wood/cement ratios by weight of 10:90, 20:80 and 30:70 respectively at a target density of 1000kg/m3. Physical, mechanical and sorption properties of the boards were evaluated. About 50% of the eucalyptus particles were retained on 0.85 to 2.36 mm sieve sizes. The loose bulk density ranged between 118 and 136 kg/m 3 at a moisture content of 8.8 %. Water absorption by the particles at 24 hours ranged between 286.0% and 433.0%. Modulus of rupture (0.4 - 3.6 MPa), flexural toughness (0.02 - 0.15 KJ/m 2 ), and tensile strength (0.4 - 1.2 MPa) of the boards fell within acceptable limits. In virtually all s...

African Journal of Sustainable Development, 2016

Rattans have been used for various purposes ranging from furniture and art works to cement compos... more Rattans have been used for various purposes ranging from furniture and art works to cement composites. Plastic composites are however more dimensionally stable than cement composites because plastic creates a moisture barrier against water ingress. There is paucity of information on properties of plastic composites made from rattan canes. Therefore, the strength properties and thermal stability of plastic composites reinforced with rattan fibers were investigated in this work. Particles of rattan species (Eremospatha macrocarpa (EM) and Laccosperma secundiflorum (LS)) were blended with High-Density Polyethylene (HDPE) to produce fiber reinforced plastic composites (FRPC) viz: EM, LS and EM+LS using formulations of 50:41 and 55:36 rattan: HDPE. Flexural tests and dimensional stability (water absorption and thickness swelling) of the rattan composites were determined. The results obtained revealed that the rattan composites possessed adequate strength and had low water absorption an...

Journal of Applied Science, Engineering and Technology, 2009

The effects of aqueous extraction and removal of silified epidermis from rattan canes on the maxi... more The effects of aqueous extraction and removal of silified epidermis from rattan canes on the maximum hydration temperature (T max ) and setting time (t max ) of two rattan cane species, Calamus deerratus and Lacosperma secundiflorum, mixed with Portland cement were investigated. T max ranged from 37.0 to 58.6 0 C and from 43.1 to 56.8 0 C for the C. deerratus and L. secundiflorum composites respectively while tmax was from 3.7 to 26.5 hrs and 7.4 - 25.7 hrs. Aqueous extraction increased the T max and reduced the t max of the rattan-cement mixes while removal of epidermis generally caused reduction in both Tmax and t max . The two rattan species seemed more amenable to cold than hot water extraction. Although cement inhibition of the Calamus species was greater than that of Lacosperma species, aqueous extraction improved the t max of the Calamus-cement composite more than Lacosperma-cement composite. Epidermis removal, species, aqueous pre-treatment and their interactions had signifi...

Rattan cane is a relatively abundant lignocellulosic in Africa and Asia that could be used for wo... more Rattan cane is a relatively abundant lignocellulosic in Africa and Asia that could be used for wood-cement composite production. However, rattans tend to inhibit cement setting. This study investigated the effects of cane peeling and aqueous extraction on maximum hydration temperature (Tmax) and setting time (tmax) rattancement-water systems using Calamus deerratus and Lacosperma secundiflorum rattan species. Peeling was done manually to remove the silified epidermis before hammer-milling to obtain cane particles. Portions of the particles were soaked in de-ionised cold (25C) and hot water (80C) respectively for 30 minutes. Findings showed that aqueous extraction improved the Tmax and reduced the tmax of the rattan-cement mixtures while peeling caused reduction in both Tmax and tmax. The two rattan species seemed more amenable to cold rather than hot water extraction. Peeling, species, aqueous pre-treatment and their interactions had significant effects on the setting time of the ra...

Journal of Applied Science, Engineering and Technology, 2009

An investigation was conducted to determine the optimum water to cement ratio for a locally manuf... more An investigation was conducted to determine the optimum water to cement ratio for a locally manufactured Portland cement for use in wood composites. The effects of pre-processing and calcium chloride (CaCl2) on the compatibility of two rattan canes (Calamus deerratus and Lacosperma secundiflorum) with cement were also assessed using the compatibility factor (CA) approach. An optimum water: cement ratio of 0.45 was obtained. Generally the two rattan species were compatible with cement. The CA factors increased with increasing levels of CaCl2 concentration (65.2% to 101.5% for C. deerratus and 71.2% to 103.5% for L. secundiflorum at 0 to 3% concentrations). Removal of the silified epidermis (pre-processing) had more significant effect (P ≤ 0.05) on the compatibility of C. deerratus with cement than in the L. secundiflorum species. Also, the particles of the Lacosperma species were more compatible with cement than those of the Calamus species probably due to the anatomy and other variations in the two species. Keywords: Rattan, Calcium chloride, cement compatibility

The feasibility of using rattan canes (Laccosperma secundiflorum and Eremospatha macrocarpa) as r... more The feasibility of using rattan canes (Laccosperma secundiflorum and Eremospatha macrocarpa) as reinforced fillers for high density polyethylene based plastic composite production was investigated. Extruded composites were tested for water sorption, tensile and thermal properties. The results obtained indicated that the rattan composites were dimensionally (water absorption: 2.2 - 21.4%; thickness swell: 0.9 – 5.3%) and thermally stable (Tc: 116.8 – 118.2ₒC) and possessed adequate tensile properties (7.3 – 21.7MPa). Composites made from L. secundiflorum had higher strength and thermal properties but lower sorption values compared to those of E. macrocarpa. Differences in the densities of the composites and the anatomical structures of the rattans seemed to influence properties of the composites.

Journal of Applied Science, Engineering and Technology, Sep 15, 2021

Bio plastics produced from cassava starch plasticised with glycerol and sorbitol and reinforced w... more Bio plastics produced from cassava starch plasticised with glycerol and sorbitol and reinforced with Gmelina arborea wood fibres at 0 20% fibre contents, 212 and 650 µm fibre sizes were test ed for strength properties. The results obtained revealed that the bio composites had strength properties: tensile strength (0.13 3.34MPa), moduli (1.99 36.31MPa), extension at break (7.08 18.85 mm) comparable with those previously reported in literat ure. Fibre size significantly affected the tensile strength while fibre content significantly affected the moduli and extension at break of the bio composites. Biocomposites produced with sorbitol had significantly higher tensile strength, moduli and exten sion at break than those produced with glycero

Journal of Tropical Forest Science, 2012

ADEFISAN OO, IDRIS A & OJEABULU J. 2012. Effects of particle size, composite mix and cold water t... more ADEFISAN OO, IDRIS A & OJEABULU J. 2012. Effects of particle size, composite mix and cold water treatment on the compressive strength of Eremospatha macrocarpa-cement composite. Rattan-cement composites were manufactured using different particle sizes (0.60,0.85 and 1.18 mm) of un treated Eremospatha macrocarpa cane and those treated in cold water using cement-sand ratio of 1:3 and 10% of rattan based on the cement mass. Specimens were tested for compressive strength after 28 days of curing. Increasing the particle size and inclusion of sand in the composite mix reduced the compressive strength while pre-treatment with cold water enhanced the compressive strength. The compressive strength of E. marcocarpa-cement composites was influenced by the interactions of pre-treatment and particle size as well as pre-treatment, particle size and composite mix.

Journal of Tropical Forest Science, 2011

simen. Kesesuaian rotan Eremospatha macrocarpa yang tidak dirawat dalam penghasilan komposit beri... more simen. Kesesuaian rotan Eremospatha macrocarpa yang tidak dirawat dalam penghasilan komposit berikatan simen (CBC) dan kesan rawatan air sejuk terhadap keserasian spesies ini dengan simen dikaji menggunakan pendekatan ujian penghidratan. Partikel E. macrocarpa dicampur dengan simen dan air serta dimasukkan ke dalam kelalang termo yang ditebat. Kenaikan suhu diawasi selama 24 jam. Kesesuaian spesies dalam penghasilan CBC dinilai berdasarkan tempoh pensetan (t max ), suhu penghidratan maksimum (T max ) dan nisbah masa (t R ). Nilai-nilai t max , T max dan t R bagi komposit simen masing-masing berjulat dari 7.2 jam–8.5 jam, 55.0 o C–57.1 o C dan 1.2–1.4. Rawatan dengan air sejuk mengurangkan t max , T max dan t R komposit simen masing-masing sebanyak 15.3%, 3.7% and 14.3%. Rawatan air sejuk menjadikan partikel E. macrocarpa yang tidak dirawat sesuai diguna bersama-sama simen.

International Journal of Composite Materials, 2016

The feasibility of developing non-conventional composite tiles using fibres extracted from Cissus... more The feasibility of developing non-conventional composite tiles using fibres extracted from Cissus populnea was investigated. C. populnea stems were sourced from a local market in Ibadan, processed and used for cement composites tile production. A manually-operated tile making machine was designed and constructed. The machine was able to produce 50-pieces of 200x100x10.5 mm of composite-tiles per hour. The tiles were conditioned and tested for dimensional stability and mechanical properties in accordance with ASTM D 1037-00. Results obtained indicated that the tiles were dimensionally stable with low sorption and swelling rates but had moderate strength suitable as insulating components such as wall and floor tiles. Pre-treatment with calcium chloride significantly enhanced the dimensional stability but reduced the strength properties.

Arid Zone Journal of Engineering, Technology and Environment, 2021

The excessive reliance on plastic materials made from fossil-fuel based and its ineffective waste... more The excessive reliance on plastic materials made from fossil-fuel based and its ineffective waste management leads to environmental pollution due to their non-biodegradable nature. This study examined the production and testing of bio-composites from Gmelina Arborea wastes and thermoplastic starches as a polymer matrix. Particles of G. Arborea sawdust were obtained from a local sawmill while dry powdered corn starches were sourced from the chemicals market, Ojota, Lagos, Nigeria. Bio-composites were produced by mixing 40 g of corn starch, glycerol/sorbitol, and fractions of prepared G. Arborea (650µm particle sizes) fibre at 0 to 20% (wt/wt of fibre to polymer matrix) were added. The slurries were poured into a mould in accordance with ASTM D638 for tensile strength test samples. The results revealed that the thermoplastic starches, particle sizes, plasticizers, and wood fibre loading significantly affected the tensile strengths, tensile modulus, elongation at break of the bio-compo...

Journal of Applied Science, Engineering and Technology, 2009

This study investigated the effects of wood-cement ratio, calcium chloride ( CaCl 2 ) addition (0... more This study investigated the effects of wood-cement ratio, calcium chloride ( CaCl 2 ) addition (0-3%) and cold water extraction on strength and sorption properties of cementbonded composites produced from eucalyptus (Eucalyptus tereticornis Sm.) veneer waste. Hammer-milled particles were characterized and used. Boards measuring 150 x 150 mm were manufactured in a low pressure system at wood/cement ratios by weight of 10:90, 20:80 and 30:70 respectively at a target density of 1000kg/m3. Physical, mechanical and sorption properties of the boards were evaluated. About 50% of the eucalyptus particles were retained on 0.85 to 2.36 mm sieve sizes. The loose bulk density ranged between 118 and 136 kg/m 3 at a moisture content of 8.8 %. Water absorption by the particles at 24 hours ranged between 286.0% and 433.0%. Modulus of rupture (0.4 - 3.6 MPa), flexural toughness (0.02 - 0.15 KJ/m 2 ), and tensile strength (0.4 - 1.2 MPa) of the boards fell within acceptable limits. In virtually all s...

African Journal of Sustainable Development, 2016

Rattans have been used for various purposes ranging from furniture and art works to cement compos... more Rattans have been used for various purposes ranging from furniture and art works to cement composites. Plastic composites are however more dimensionally stable than cement composites because plastic creates a moisture barrier against water ingress. There is paucity of information on properties of plastic composites made from rattan canes. Therefore, the strength properties and thermal stability of plastic composites reinforced with rattan fibers were investigated in this work. Particles of rattan species (Eremospatha macrocarpa (EM) and Laccosperma secundiflorum (LS)) were blended with High-Density Polyethylene (HDPE) to produce fiber reinforced plastic composites (FRPC) viz: EM, LS and EM+LS using formulations of 50:41 and 55:36 rattan: HDPE. Flexural tests and dimensional stability (water absorption and thickness swelling) of the rattan composites were determined. The results obtained revealed that the rattan composites possessed adequate strength and had low water absorption an...

Journal of Applied Science, Engineering and Technology, 2009

The effects of aqueous extraction and removal of silified epidermis from rattan canes on the maxi... more The effects of aqueous extraction and removal of silified epidermis from rattan canes on the maximum hydration temperature (T max ) and setting time (t max ) of two rattan cane species, Calamus deerratus and Lacosperma secundiflorum, mixed with Portland cement were investigated. T max ranged from 37.0 to 58.6 0 C and from 43.1 to 56.8 0 C for the C. deerratus and L. secundiflorum composites respectively while tmax was from 3.7 to 26.5 hrs and 7.4 - 25.7 hrs. Aqueous extraction increased the T max and reduced the t max of the rattan-cement mixes while removal of epidermis generally caused reduction in both Tmax and t max . The two rattan species seemed more amenable to cold than hot water extraction. Although cement inhibition of the Calamus species was greater than that of Lacosperma species, aqueous extraction improved the t max of the Calamus-cement composite more than Lacosperma-cement composite. Epidermis removal, species, aqueous pre-treatment and their interactions had signifi...

Rattan cane is a relatively abundant lignocellulosic in Africa and Asia that could be used for wo... more Rattan cane is a relatively abundant lignocellulosic in Africa and Asia that could be used for wood-cement composite production. However, rattans tend to inhibit cement setting. This study investigated the effects of cane peeling and aqueous extraction on maximum hydration temperature (Tmax) and setting time (tmax) rattancement-water systems using Calamus deerratus and Lacosperma secundiflorum rattan species. Peeling was done manually to remove the silified epidermis before hammer-milling to obtain cane particles. Portions of the particles were soaked in de-ionised cold (25C) and hot water (80C) respectively for 30 minutes. Findings showed that aqueous extraction improved the Tmax and reduced the tmax of the rattan-cement mixtures while peeling caused reduction in both Tmax and tmax. The two rattan species seemed more amenable to cold rather than hot water extraction. Peeling, species, aqueous pre-treatment and their interactions had significant effects on the setting time of the ra...

Journal of Applied Science, Engineering and Technology, 2009

An investigation was conducted to determine the optimum water to cement ratio for a locally manuf... more An investigation was conducted to determine the optimum water to cement ratio for a locally manufactured Portland cement for use in wood composites. The effects of pre-processing and calcium chloride (CaCl2) on the compatibility of two rattan canes (Calamus deerratus and Lacosperma secundiflorum) with cement were also assessed using the compatibility factor (CA) approach. An optimum water: cement ratio of 0.45 was obtained. Generally the two rattan species were compatible with cement. The CA factors increased with increasing levels of CaCl2 concentration (65.2% to 101.5% for C. deerratus and 71.2% to 103.5% for L. secundiflorum at 0 to 3% concentrations). Removal of the silified epidermis (pre-processing) had more significant effect (P ≤ 0.05) on the compatibility of C. deerratus with cement than in the L. secundiflorum species. Also, the particles of the Lacosperma species were more compatible with cement than those of the Calamus species probably due to the anatomy and other variations in the two species. Keywords: Rattan, Calcium chloride, cement compatibility

Journal of Applied Sciences, 2012