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Viva vorce izreen farah

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This is my viva vorce slide for my master degree

This is my viva vorce slide for my master degree

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  • 1. PROPERTIES OF LOW DENSITY WOOD IMPREGNATED WITH PHENOLIC RESIN ADMIXED WITH UREA Supervisory Committee: Associate Professor Dr. Zaidon Ashaari Professor Dr. Hamami Sahri Associate Professor Dr. Edi Suhaimi Bakar NUR IZREEN FARAH BINTI AZMI GS 24471 Master Of Science (Wood Science & Technology)
  • 2. OUTLINE OF PRESENTATION• Introduction• Problem Statement• Objectives• Literature Review• Methodology• Statistical Analysis• Result And Discussion• Conclusions• Recommendations• References
  • 3. INTRODUCTION• World demand for forest wood product is growing since the past years;• Rapid declining of the global availability of precious commercial timbers;• Industries need to find another alternative;• Issue of underutilized wood species;• A lot of potentially valuable trees being left over after forest clearing operations. Have a great potential and is extensively being used in research study Limitations: •Low natural durability •Poor strength properties Dyera constulata Endospermum diadenum •Dimensional instability Advantages: •Faster grow •Exotic colors and textures •Cheaper price •Abundance availability Macaranga sp. Azadirachta excelsa
  • 4. CONT..• Modify wood to improve the properties, depending on the ultimate applications;• Sufficient amount of wood raw material for incoming years for the development and growth of forest product industry;• Impregnation of solid wood with Lmw-PF resin + cured using heat: provide tremendous wood enhancement properties includes mechanical strength, dimensional stability in terms of ASE and durability of wood against decay (Zaidon et al. 2009, 2010, 2011; Nur Izreen et al. 2011) Impreg wood Compreg wood Resin treated wood cured with Resin treated wood compressed heat without compression while the resin is cured in the wood structure
  • 5. PROBLEM STATEMENT• High level of formaldehyde emission (FE) compared to required global standard;• Generated from free, unreacted formaldehyde during curing;• Harmful to human body; human carcinogen (cancer causing agent) (WHO)• High number of methylol groups in the main polymer chains of Lmw-PF resin responsible for the longer time required to cure the resin (Hoong et al. 2010);• Formaldehyde scavenger: urea, ammonium phosphate, potassium sulphite and sodium thiosulphate (Roffael, 1993);• Urea: low cost and can improve curing process (Zaidon, 2009) ;• Able to reduce FE from compreg products made from sesenduk (Endospermum diadenum) and mahang (Macaranga sp.) (Zaidon, 2009, 2010, 2011) and impreg product made form jelutong (Dyera constulata) (Nur Izreen et al. 2011);• Unfortunately, when enough urea is mixed to achieve significant reduction of FE, some of physical properties of the resultant product are severely affected;• Introduced urea will react with the free formaldehyde and form a rigid cross-linked polymer of urea-formaldehyde (UF) and phenol-urea formaldehyde (PUF).
  • 6. OBJECTIVES• Main objective: – To determine the effect of phenolic resin admixed with urea (formaldehyde scavenger) on the properties of low density wood, Dyera constulata and Endospermum diadenum.• Specific objectives: – To investigate the FE of Dyera constulata and Endospermum diadenum impregnated with Lmw-PF admixed with urea using vacuum pressure process; – To identify the functional groups of compound presence in the treated wood using Fourier Transform Infrared Spectroscopy (FT-IR); – To evaluate the effect of processing variables on mechanical properties, dimensional stability and decay durability of the impregnated wood.
  • 7. LITERATURE REVIEW– As timber resources become scarcer, and the real prices of primer species rise, the underutilized wood species and small-sized logs will gain wider acceptance;– Impregnation treatment: depositing any of a bulking agent within the swollen wood structure;– No reaction taking place -monomers are not attached or bonded to the cell wall components but change from soluble monomers into water-insoluble polymers after polymerization which will not leach out in water (Nonbonded-nonleachable );– Kajita and Imamura (1991) used the Lmw-PF resin to improve the physical and biological properties of particleboards while Anwar et al. (2006) and Loh et al. (2011) studied the properties improvement by using the resin on bamboo strips and oil-palm stem veneer respectively.
  • 8. METHODOLOGY• Materials – Low density wood, jelutong (Dyera constulata) and sesenduk (Endospermum diadenum), obtained from Ayer Hitam Forest Reserve, Puchong, Selangor; – Low molecular weight phenol formaldehyde (Lmw-PF) resin (Mw 600, 45% solid content), supplied by Malaysian Adhesive Chemical, Shah Alam; – Urea in the form of granules, as formaldehyde scavenger, readily available in the market
  • 9. PREPARATION OF SAMPLES Flat sawn into samples Rank according to density; each group Jelutong : 150x50x5mm contain samples with varied density Sesenduk: 150x50x10mmTreatment combinations:3 treating concentrations;3 curing time;Untreated samples (control)(3 x 3 x 1) Measure weight and dimension
  • 10. PREPARATION OF MATERIALSDilute Lmw-PF into 20, 30, 30% urea based on solid PF40% concentration pH for PF admixed with urea: 9-11 (alkaline) Mix with prepared PF resin separately
  • 11. TREATMENT PROCESSMeasure initial weight Apply some loads 85kPa vacuum, 15 min 340kPa pressure, 30 minPrecure:60°C for 30 minCure: 150°C for 60, 90, 120 min Fill with treating solution(Based on preliminary study)
  • 12. PROPERTIES EVALUATION Vacuum-soaking & water vapour test forFormaldehyde dimensional stabilityemission test Decay resistance testMOR and MOE in FTIR analysis bending test
  • 13. STATISTICAL ANALYSIS• Statistical analysis was carried out using a two-way analysis of variance (ANOVA) to evaluate the effects of treatment combinations on the formaldehyde emission, physical and mechanical properties, dimensional stability, and durability on impreg product. Duncan Multiple Range Test (DMRT) at p ≤ 0.05 was used to further evaluate these effects.
  • 14. RESULT & DISCUSSIONSummary of ANOVA (p ≤ 0.05)Variables df Density WPG MOR MOE ASE1 WA1 TS1 ASE2 WA2 TS2 Fungal JelutongCon 2 0.000 0.576 0.173 0.028 0.582 0.000 0.000 0.099 0.001 0.401 0.000Cur 2 0.001 0.007 0.677 0.126 0.551 0.000 0.002 0.007 0.000 0.011 0.000Con*cur 4 0.747 0.913 0.173 0.333 0.719 0.124 0.075 0.545 0.231 0.100 0.000 SesendukVariables df Density WPG MOR MOE ASE1 WA1 TS1 ASE2 WA2 TS2 FungalCon 2 0.047 0.087 0.265 0.092 0.009 0.000 0.047 0.000 0.000 0.003 0.000Cur 2 0.001 0.007 0.311 0.962 0.920 0.768 0.877 0.927 0.020 0.173 0.002Con*cur 4 0.044 0.290 0.936 0.878 0.039 0.349 0.127 0.032 0.404 0.073 0.011 Note: Mean in bold properties significantly affected by treatment variables at p≤0.05
  • 15. FORMALDEHYDE EMISSION 3.5 y = 9.089x - 0.068 3 R² = 0.997 2.5Std.Solution (ppm) 2 1.5 1 0.5 0 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 Absorbance
  • 16. CONT.. Jelutong Sesenduk NU+90 min WU+60 min WU+90 min WU+120 min NU+90 min WU+60 min WU+90 min WU+120 min 180 166.11 200 187.99 Formaldehyde Emission, ppm Formaldehyde Emission, ppm 160 180 140 160 141.97 130.95 120 105.08 140 100 120 83.42 78.06 100 36.6 48.45 80 42.82 80 33.26 36.89 35.19 44.81 50.97 60 29.93 60 42.96 44.07 10.03 13.82 40 14.81 40 23.59 20 8.38 13.46 20 0 0 20% 30% 40% 20% 30% 40% PF concentration,% PF concentration, % 70% 90% Urea successfully absorbed some of free formaldehyde in the resin system during polymerization;Reactive urea easily bond with the free formaldehyde released by some of methylol groups from the resin;Min (8.38 ppm) still far beyond the global standard threshold limits 0.1ppm for indoor applications;FE with curing time -methylol group in oligomeric chain of PF converted to methylene bridge;Another alternatives: increase the concentration of urea; prolong the curing time
  • 17. FT-IR ANALYSIS Literature Observed Compound/ Band wavenumber (cm-1) Wavenumber (cm-1) Functional group numbers 3336 3335 O-H stretch 1120 Jelutong N-H stretch100 2882 2887 CH- stretch in methyl- 2 80 and methylene groups 20% 60 3 30% 1722 1733 C=O stretch 3 2 40 5 40% 1633 1640 C=C aromatic ring 4 4 6 Control 20 1 1478 1467 C-H aliphatic 5 0 7 1227 1227 C-O stretch 6 934 715 496 4000 3781 3562 3343 3124 2905 2686 2467 2248 2029 1810 1591 1372 1153 1020 1020 -C-OH 7120 Sesenduk •Kornel et al. 1992 detected a significant bands of pure100 UF resin with a pronounced peak Band 1 at 3336 cm-1; 80 20% •PUF resin: synthesized by the reaction of TMeP with 60 3 urea, under acidic or alkaline conditions (Poljansek and 2 30% 40 40% Krajnc (2005); 20 4 5 6 Control •Addition of urea to Lmw-PF results in the formation of 1 0 7 cocondensed PUF resin; shown by Band 6 (1227 cm-1) 971 738 505 4000 3767 3534 3301 3068 2835 2602 2369 2136 1903 1670 1437 1204 which corresponded to the C-O stretch vibrations of phenolic rings.
  • 18. PHYSICAL PROPERTIES Treatment Density Density Gain WPG combination (kg/m3) (%) (%) Jelutong Untreated 396E - -Density 20% 60 min 59.1 630CD 84.13AB 2-3 folds; 20% 90 min 594D 50.0 64.31BC PF resin monomer was successfully 20% 120 min 583D 47.2 54.55Cpenetrate into the wood cellular structure 30% 60 min 744AB 87.9 85.31ABand filled up the void vessels of wood. 30% 90 min 690BC 74.2 75.03BC 30% 120 min 649CD 63.9 68.55BC 40% 60 min 797A 101.3 91.06AWeight Percent Gain 40% 90 min 759AB 91.7 80.93AB(based on constant weight in conditioning 40% 120 min 698BC 76.3 77.51BCroom before and after treatment) Sesenduk 50-100%; Untreated 348E - - High WPG indicates that the PF solution 20% 60 min 737ABC 112.4 105.2Bhas penetrated and bulked into the cell wall; 20% 90 min 697BCD 100.9 84.43BCDE with curing time -partly cure resin may 20% 120 min 636D 83.3 70.79Econsist of some water molecule which would 30% 60 min 797A 129.7 127.5Aadd to the weight of the treated wood. 30% 90 min 742ABC 113.8 95.46BCD 30% 120 min 669CD 92.8 75.24DE 40% 60 min 802A 131.1 101.9BC 40% 90 min 749AB 115.9 83.11BCDE 40% 120 min 704BCD 102.9 80.34CDE
  • 19. MECHANICAL PROPERTIES MOR 10-50% Treatment MOR MOE MOE 20-70% combination (MPa) (MPa) R² = 0.4685 R = 0.6845 Jelutong 90 B D 85Untreated 62.95 6124 A BC20% 60 min 79.40 8255 80 MOR, Mpa A AB20% 90 min 80.70 9579 AB 7520% 120 min 77.73 8903ABC AB C30% 60 min 70.31 7752 70 A ABC30% 90 min 80.90 8744 65 BC30% 120 min 69.98AB 8442 80.71 A 9192 ABC 6040% 60 min 78.57 A 8985 ABC 600 700 800 90040% 90 min A A Density, kg/m340% 120 min 83.92 10432 Sesenduk Failure mode: B BUntreated 55.91 5064 AB A20% 60 min 77.63 7914 AB A20% 90 min 70.92 7776 A20% 120 min 73.20AB 7603 A30% 60 min 81.10 8135A AB30% 90 min 70.25 7631A AB30% 120 min 66.93 7840A 85.34 A Untreated : Impreg :40% 60 min 8359A40% 90 min 83.59 A Splintering tension Simple tension 8937A AB40% 120 min 76.69 8630A
  • 20. DIMENSIONAL STABILITY Treatment ASE1 WA1 TS1 ASE2 WA2 TS2 combinations (%) (%) (%) (%) (%) (%) Jelutong • ASE: bulking of cell wall 20% 60 min 28.26AB 43.56B 2.00BCD 10.14A 13.12B 5.09AB and reduction in 90 min 27.67AB 38.19C 1.07EF 18.92B 10.37C 4.23BCD hydrophilicity of wood after 120 min 35.39A 36.82CD 0.82F 25.21C 9.69C 4.02BCD 30% 60 min 4.92C 35.88CD 3.01B 13.28A 13.90B 4.49BC modification 90 min 15.84BC 33.57D 2.71BC 12.54A 9.69C 4.52BC 120 min 14.02BC 26.64E 1.80CDEF 26.45C 9.20C 3.09D • Aikfe (2010) found ASE 40% 60 min 17.94BC 24.72E 2.85B 25.91C 10.24C 4.66BC of Macaranga spp. treated 90 min 25.98AB 20.55F 1.52DEF 26.08C 8.60C 3.54CD without urea was more 120 min 14.41BC 19.91F 2.51BCD 26.97C 8.47C 4.26BCD than 60%. Control - 63.17A 4.18A - 18.96A 5.9A Sesenduk • The presence of urea 20% 60 min 36.66ABC 67.98B 3.01BCD 23.56BC 11.32B 3.25BC increased Mw of resin 90 min 31.17C 69.10B 3.30B 21.68C 10.81BCD 3.37B 120 min 34.94BC 70.46B 3.06BCD 18.13C 11.04BC 3.28BC system, thus limit the 30% 60 min 40.02ABC 41.35C 2.64BCD 13.03C 10.21CD 3.10BC penetration into the cell 90 min 39.13ABC 46.47C 2.91BCD 23.30BC 9.99D 2.61CD wall of treated wood. 120 min 31.43C 45.11C 3.19B 16.45C 10.00D 3.11BC 40% 60 min 37.30ABC 45.15C 3.12BCD 36.86A 10.04D 3.14BC 90 min 42.89AB 30.81D 2.24CD 25.24ABC 9.01E 2.66CD*Note: 1= water soaking test (24h) 120 min 44.87A 29.37D 2.17D 34.23AB 8.89E 2.26D2= water vapour test (constant weight) Control - 208A 5.30A - 17.15A 4.18A
  • 21. Cont.. Jelutong Sesenduk CT60 min CT90 min CT120 min Control Control CT60 min CT90 min CT120 min 30 30 25 25 20 20WA, % WA, % 15 15 10 10 5 5 0 0 0 5 10 15 20 25 0 5 10 15 20 25 Day Day CT60 min CT90 min CT120 min Control Control CT60 min CT90 min CT120 min 8.0 6 7.0 6.0 5 5.0 4 TS, % TS, % 4.0 3 3.0 2 2.0 1 1.0 0.0 0 0 4 8 12 16 20 24 28 0 5 10 15 20 25 Day Day
  • 22. DURABILITY 12 weeks of exposure to Pycnoporous sanguiness: Jelutong 18.4020.0 60 min 90 min 120 min15.010.0 4.80 3.42 2.20 0.60 5.0 1.10 0.00 0.60 0.00 0.00 0.0 Control 20% 30% 40% Untreated Treated Sesenduk 26.3030.025.0 60 min 90 min 120 min Average Weight Loss Indicated Resistance Class (%)20.015.0 0-10 Highly Resistant 4.2010.0 4.00 11-24 Resistant 3.20 1.10 3.10 3.30 5.0 1.20 0.30 0.30 25-44 Moderately Resistant 0.0 Control 20% 30% 40% 45-100 Slightly Resistant or Nonresistant
  • 23. Effect of FE levels on WL Jelutong Sesenduk 40 20 70 20 35 18 18 16 60 30 16 FE (ppm) 14 WL (%) 50 14 25 12 12 FE (ppm) WL (%) 40 20 10 10 15 8 30 8 6 20 6 10 4 4 5 2 10 2 0 0 0 0 20 30 40 20 30 40 PF Concentrations (%) PF Concentrations (%)
  • 24. CONCLUSIONS• The addition of 30% urea scavenger based on solid PF greatly reduced the level of FE for both wood species by 70-90%. The significant reduction however still far beyond the global standard threshold limits.• The addition of urea to Lmw-PF resulted in the formation of UF and cocondensed PUF resin. This was shown by FT-IR at the absorption peak 3335 cm-1 and 1227 cm-1 respectively.• The properties of impreg Dyera constulata and Endospermum diadenum treated with Lmw-PF resin was superior than the untreated wood, indicating that the treatment had successfully improve the strength, dimensional stability and durability against fungi attack.
  • 25. RECOMMENDATIONS Treatment with 40% Lmw-PF admixed with urea and cure for 120 min is recommended to compensate the properties of jelutong and sesenduk which can be used for producing impreg product for parquet flooring, paneling, furniture components and also for exterior applications. For further studies, 30% urea based on solid PF can be used to reduce formaldehyde emission since it has been proven able to reduce the level of FE up to 90%. However, the curing time should be prolonged so that more polymerization would occur.
  • 26. REFERENCES• Hoong, Y.B., Paridah, M.T., Loh, Y.F., Koh, M.P., Luqman, C.A., and Zaidon, A. 2010. Acacia mangium tannin as formaldehyde scavenger for low molecular weight phenol formaldehyde resin in bonding tropical plywood. Journal of Adhesion Tech. 24: 1563- 1664.• Kajita, H., and Imamura, Y. 1991. Improvement of physical and biological properties of particleboards by impregnation with phenolic resin. Journal of Wood Sci. Tech. 26: 63-70.• Nur Izreen, F.A., Zaidon, A., Rabiatol Adawiah, M.A., Bakar, E.S., Paridah, M.T., Mohd Hamami, S., Anwar, and U.M.K. 2011. Enhancing the Properties of Low Density Hardwood Dyera constulata Through Impregnation with Phenolic Resin Admixed with Formaldehyde Scavenger. Journal of Applied Science. 11(20): 3474-3481.• Rowell, R.M., and Youngs, R.L. 1981. Dimensional stabilization of wood in use. U.S. For. Serv., For. Prod. Res. Note FPL-0243. Forest Product Laboratory, Wisconsin.• Wallström, L., Lindberg, K.A.H. 1999. Measurement of cell wall penetration in wood of water-based chemicals using SEM/EDS and STEM/EDS technique. Wood Sci Technol. 33: 111–122.• Zaidon, A. 2009. Improvement of raw materials from underutilised timber species through chemical and densification treatments for value added laminated products. End of Reports (unpublished) submitted to the Ministry of Science and Technology, Malaysia. Rep. No. 06-01-04-SF0656.
  • 27. PRELIMINARY STUDY• Objective: To determine the curing time of LmwPF;• Justification: Important to estimate the time required for the complete polymerization in the treated wood;• Methods: 1) Determination of PF hardening time • Diluted PF with distilled water to produce 20%, 30% and 40% Lmw-PF; • Poured 50 ml of the prepared PF solution separately into a petri-dish; • Heated in an oven at 150ºC; • Observed the hardening process every 5 min and record the time of PF resin start to harden.
  • 28. • Methods: 2) Determination of heat transfer into wood • Use thermocouple meter to measure the time required for the heat to transfer into the central part of the wood; • Drill a small hole on the center of sample; • Insert thermocouple wire into the hole of the wood, and the wood is partly immersed into the oil bath at 150±2ºC • Record the time required for the hole to reach 150±2ºC. Result: PF PF Heat Curing concentration hardening transfer resin (%) time (min) into wood (min) (min) 20 60 30 60 + 30 = 90 60-120 min was 30 55 30 55 + 30 = 85 selected for curing time 40 50 30 50 + 30 = 80 BACK