اثر مادۀ لیگنوسلولزی بر فرایند هیدراتاسیون، ویکات و خواص مکانیکی تخته خرده‌چوب-گچ

نوع مقاله : مقاله پژوهشی

نویسندگان

1 بیکار

2 دانشگاه زابل

چکیده

در این مطالعه امکان ساخت تخته خرده‌چوب-گچ (GBPB) از ذرات باگاس (Saccharum ossicinarum l.) و کاه گندم (Oryza sativa l.) با نسبت سطوح مختلف و نسبت گچ: مواد لیگنوسلولزی بررسی شد. نسبت باگاس: کاه گندم از 100: 0، 75/93: 25/6، 5/87: 5/12، 25:75، 50:50، 25/75 و 0: 100 در GBPB آزمایشگاهی با استفاده از دو نسبت گچ به مواد لیگنوسلولزی (LR : G) یعنی 75/1:2 و 25/1:3 با دانسیتۀ 05/1 و 20/1 گرم بر سانتی‌متر مکعب ساخته شد. مقاومت خمشی (MOR)، مدول الاستیسیته (MOE) و چسبندگی داخلی (IB) تخته‌ها و همچنین فرایند هیدراتاسیون خمیر گچ بررسی شد و تحلیل آماری و تحلیل واریانس به‌منظور بررسی امکان ساخت از پسماندهای کشاورزی در تولید GBPB تجاری انجام گرفت. بررسی هیدراتاسیون نشان داد که مواد لیگنوسلولزی که دارای مواد استخراجی بیشتری هستند سبب کاهش دمای هیدراتاسیون و افزایش زمان سخت شدن مادۀ معدنی خواهند شد. نتایج تجربی نشان دادند که مدول گسیختگی و مدول الاستیسیتۀ تخته‌های حاوی 0 ، 25/6  و 5/12 درصد کاه گندم با نسبت 75/1:2 بیشتر از پانل‌های ساخته‌شده بود. به‌طور کلی، تخته‌هایی که از درصد بیشتر ذرات باگاس در ساختشان استفاده شده، مقاومت مطلوب‌تری دارند و پاسخگوی مناسبی در زمینۀ رفع احتیاجات هستند.

کلیدواژه‌ها


عنوان مقاله [English]

Effect Lignocellulosic Materials on Hydration Process, Vicat and Mechanical Properties of Gypsum Bonded Particle Board

نویسندگان [English]

  • meisam kamyab 1
  • morteza nazerian 2
1
2
چکیده [English]

Gypsum-bonded particleboard panels were made from various mixture of bagasse (Saccharum ossicinarum l.) and wheat (Oryza sativa l.) straw particles bonded with different ratio level of particles/gypsum. This study examined possible feasibility of bagasse and wheat straw particles in the production of gypsum-bonded particleboard (GBPB). One-layer experimental GBPB with density of 1.05 and 1.20 g/cm3 29 were manufactured at bagasse/wheat straw ratio of 100:0, 93.75:6.25, 87.50:12.50, 75:25, 50:50, 25:75 and 0:100 using two particle/gypsum compositions of 1:2.75 and 1:3.25 and density of 1.05 and 1.20 g/cm3. Modulus of rupture (MOR), modulus of elasticity (MOE) and internal bond (IB) characteristics of the boards and gypsum dough hydration process were evaluated. statistical analysis was performed in order to examine possible feasibility of these agricultural residues in commercial GBPB manufacturing. hydration results showed that , using lignocellulosic materials with higher extractives led to a reduced hydration temperature and increasing of hardening time of the mineral . The experimental results have shown that the MOR and MOE of boards containing 0%, 6.25% and 12.5 % wheat straw with LR/G ratio level of 1/2.75 were higher than those of manufactured panels.. In general, boards with a higher amount of bagasse ratio showed superior strength properties.

کلیدواژه‌ها [English]

  • Bagasse
  • Gypsum-bonded particleboard
  • Mechanical Properties
  • wheat straw
  • Hydration
[1]. Ahn, W.Y., and Moslemi, A.A. (1980). SEM examination of wood-Portland cements bonds. Journal of Wood Science,13 (2): 77-82.
[2]. Sauter, S.L. (1996). Developing composites from wheat straw. 30th International Particleboard/Composite Material Symposium. April 2-5 Washington State University, Pullman, WA, USA, pp. 197-214.
[3]. Li, X., Cai, Z., Winandy, J. E., and Basta, A.H. (2010). Selected properties of particleboard panels manufactured from rice straws of different geometries, Bioresource Technology, 101 (12): 4662–4666.
[4]. Deng, Y., Furuno, T., and Uehara, T. (1998). Improvement on the properties of gypsum particleboard by adding cement. Journal of Wood Science, 44 (2): 98-102.
[5]. Simatupang, M.H., Kasim, A., and Seddig, N. (1988). Influence of wood extractives on the setting of gypsum. Mitteilung der Bundesforschungsanstalt fur Forst-und Holz wirtschaft, Hamburg. November, Germany, pp. 311-319.
 
[6]. Simatupang, M.H. (1991). Inorganic binder for wood composites: feasibility and limitations. Wood Adhesive Forest Product Society, pp. 169-176.
 
[7]. Qian, F., Yuhe, D., Hyunjoong, K., Wen, L., Zhiwu, S., Yonggang, J., Lin, X., and Sumin, K. (2007). Observation and analysis of gypsum particleboard using SEM. Journal of Wuhan University of Technology-Mater, 22 (1): 44-47.
[8]. Hachmi, M., and Moslemi, A.A. (1989). Correlation between wood-cement compatibility and wood extractives. Forest Product Journal, 39 (6):55-58.
[9]. Simatupang, M.H., and Lu, X.X. (1985). Influence of wood extractives on hardening of gypsum plaster and on the manufacture of gypsum-bonded particleboards. Holz als Rohund Werkstoff, 43 (8): 325-331.
[10]. Dalmay, P., Smith, A., Chotard, T., Sahay-Turner, P., Gloaguen, V., Krausz, P. (2010). Properties of cellulosic fibre reinforced plaster: influence of hemp or flax fibres on the properties of set gypsum. Journal of Materials Science, 45: 793–803.
[11]. Franklin, G.L., (1954). Preparation of thin sections of synthetic resins and wood-resin composites, and a new macerating method for wood. Nature, 155: 51–59.
[12]. EN, 310. (1993). Wood based panels, determination of modulus of elasticity in bending and bending strength. European Standardization Committee, Brussels.
[13]. EN, 319. (1993). Particleboards and fiberboards, determination of tensile strength. European Standardization Committee, Brussels.
[14]. Mahajan, S., and Bhatt, O.P. (2001). Physical strength properties of standard test sheets made from bagasse and bamboo. In Paper International, 5 (3): 1-5.
[15]. Atchison, J.E., and McGovern, J.N. (1993). History of paper and the importance of agricultural residues fiber. Atlanta, GA, TAPPI Press.
[16]. Zhou, Y., and Kamdem, D.P. (2002). Effect of cement/wood ratio on the properties of cement-bonded particleboard using CCA treated wood removed from service. Forest Product Journal, 52 (3): 77–81.
[17 Singh, S.M. (1979). Investigations into the causes of poor strength of Portland cement bonded lignocellulosic materials. Journal of the Indian Academy of Wood Science, 10 (1): 15-19.
[18]. Roberts, M.H. (1967). Effect of admixtures on the composition of the liquid phase and the early hydration of reactions in Portland cement paste. Proceedings of the International Symposium on Admixtures for Mortar and Concrete. Jun. 1 Brussels, Belgium, pp. 5-29.
 
[19]. Deng, Y., and Furuno, T. (2002). Study on gypsum-bonded particleboard reinforced with jute fibers. Holzforschung, 56 (4): 440–445.
 
[20]. Aggarwal, L.K., Agrawal, S.P., Thapliyal, P.C., and Karade, S.R. (2008). Cement-bonded composite boards with arhar stalks. Cement & Concrete Composites, 30 (1): 44–51.
[21]. Mantanis, G., and Berns, J. (2001). Strawboards bonded with urea-formaldehyde resins. 35th International Particleboard/Composite Material Symposium. April 2-5 Washington State University, Pullman, WA, USA, pp. 137-144.