Effect of Mixing Three Lignocellulosic Materials with Different Cement Ratios on the Properties of Cement Bonded Particleboard

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1 J.S. Teh 12(3) 211 Journl of Siene nd Tehnology 12 (3) Deemer 211 ISSN X Sudn University of Siene nd Tehnology Effet of Mixing Three Lignoellulosi Mterils with Different Cement Rtios on the Properties of Cement Bonded Prtileord Tgelsir E. Mohmed 1, Adelzim Yssin Adelgdir 2, M.M. Meghed 3 nd Rmdn Nsser 3 1. College of Forestry nd Rnge Siene Sudn University of Siene nd Tehnology 2. Fulty of Forestry University of Khrtoum 3. Deprtment of Forestry nd Wood Tehnology, University of Alexndri-Egypt ABSTRACT: This study investigted the effets of nine different mixtures of three lignoellulosi mterils nd four rtios of ement to lignoellulosi mterils (LCM) (2.:1, 3:1, 3.:1 nd 4:1) on the properties of ement onded prtileord. The mterils were (sunt) Ai niloti sw dust, gsse nd otton stlks. They were olleted from different lotions in Sudn. Resonle pnel properties were otined from the three lignoellulosi mterils either pure or mixed using different ement/lignoellulosi mterils (C/LCM) rtios (3:1, 3.:1 nd 4: 1). The men vlues of wter sorption perent (WA %) nd the thikness swelling perent (TS %) for oth the two hours nd 24-hours soking tests, onform fvorly to figures reported in previous studies.the highest ending strength (MOR) nd modulus of elstiity (MOE) were ttined y1% sunt prtiles with ll ement/lignoellulosi mterils rtios. KEYWORDS: mixing, lignoellulosi mterils, ement, rtios, prtileord, properties. INTRODUCTION A rpid growth of the wood - sed industry hs een reported in the reent literture. The nnul survey of the wood sed pnels y World Wood Journl (Anonymous 1988) shows renewed strength in prtileord nd more interest in minerl ords nd pnels mde from gsse. Wood prtiles onded with ordinry Portlnd ement re eoming more prevlent in numer of ountries round the world. Expnding its mteril se, disovering new methods of mnufturing tehnologies nd modifying the inorgni inders re some of the spets tht re gining momentum (Suiynto, nd Kwi 1996). Extensive studies on the expnsion of the rw mteril se hve demonstrted the fesiility of produing ement onded prtileord using tropil hrdwood speies, some griulturl wste nd industril residues s well (Evn, 2, Fernndez nd Tj-on 2, Euseio 23). Cement onded prtileords seem ttrtive in extending the use of wood wste nd griulturl residues. Severl ttempts were mde in the pst to mix different types of rw mterils for prtileord mnufture. This ws done to mke use of lignoellulosi residues nd or to improve or modify the qulity of prtileord. Previous studies hve indited tht some lignoellulosi mterils re not suitle for the mnufture of ement onded prtileord. This hrteristi vries with the type of mteril. The vrition rises due to dverse effets on ement setting due to the presene of ertin extrtives (Kumr 1981),( Sndermnn et l. 196), (Sndermnn nd Kohler 1964). The ility of wood to omine with Portlnd ement is termed omptiility. The omptiility of lignoellulosi mterils with ement n e enhned 44

2 J.S. Teh 12(3) 211 y severl tretments. Hot wter nd wek lkli re mong the ommon tretments used to extrt the inhiitory sustnes in wood. Clium hloride is one of the widely used elertors of ement setting. These tretment methods were hosen to e used in this study s preliminry omptiility test. They re reltively hep nd esy to use. The present study ws set to i) exmine the effets of lending wood nd nonwood lignoellulosi mterils on the properties of ement onded prtileord nd ii) ompre properties of vrious ord types to the minimum property requirements speified in the ommeril stndrds for ement onded prtileords. MATERIALS nd METHODS Mnufturing proess The lignoellulosi mterils used were sunt (Ai niloti) swdust, gsse nd otton stlks. They were olleted from different lotions of Sudn; EL Suki Swmill, EL Gunied Sugr Ftory nd fields in EL Kmlin lolity, respetively. Ordinry Portlnd ement (produed y Al Amri Compny, Egypt) ws used s inder. Bgsse ws proessed y hmmer mill, otton stlks were proessed first in hipper nd then hmmer milled. Then the three lignoellulosi mterils were sreened using lortory sieves. The prtiles whih pssed sieve size of 4mm nd retined on sieve size of 1mm ( mesh ), were used for ement onded ords mnufture. Preliminry hydrtion tests were rried out to enhne the the omptiility of the lignoellulosi mterils under investigtion with ement. The est ommon effetive tretment ws found to e 1% NOH solution (24 hours soking) nd 3 % CCl 2 s n dditive or elertor for ement setting. The mximum hydrtion tempertures rehed were ove 6C. Hene this tretment ws hosen for the furnish tretment of ement onded prtileords. The mixtures of the three lignoellulosi mterils re shown in tle 1. They were lended in rtios of 2.:1, 3:1, 3.:1nd 4:1 with ement to wood. The lignoellulosi prtiles were weighed nd mixed with the determined mounts of dry ordinry portlnd ement. Then the right mount of CCl 2 for eh mixture ws dissolved in predetermined mount of wter. The solution ws dded to the lend of ement nd lignoellulosi mterils nd thoroughly hnd mixed in plsti ontiners for out minutes. The mount of wter used for furnish mixing ws lulted ording to the reltionship developed y Simtupng (1979). Tle 1.Different mixtures of the three lignoellulosi mterils Bord type Bgsse % Cotton stlks Sunt % % M1 1 M2 1 M3 1 M4 M M6 M7 2 2 M8 2 2 M

3 J.S. Teh 12(3) 211 Open top oxes onsisting of frme from eeh wood, se nd over of veneer plywood oted with phenoli films, were mde. The ses were fixed nd relesed from the frmes y mens of nils nd srew drivers. The oxes were designed to give 3 x 3 m for the se from inside nd frme height of 3.2 m. nd over with thikness of 2.2 m to fit tightly in the frme nd to give thikness of one entimeter for the intended ords. The mixture of ement, wter, nd lignoellulosi mterils with the dditive were formed in eh ox, y hnd. Then the squre overs of the veneer plywood were pled on the top of the mixture to press it nd ensure the desired thikness of ords. Three replites were mde from eh of the nine mixtures of the four rtios. The pnels were 3 mx 3 m X1m in dimensions nd with trgeted density of 1.2 g/m 3. The ords were pressed in ool hydruli press (Crver, model 2699) under onstnt pressure.the mount of pressures used were, 27.7 Kg/m 2, 22.2 Kg/m 2,16.67 Kg/m 2 nd 11.11Kg/m 2 depending on the ement wood rtios used. The ords were pressed for few minutes until the required pressure is rehed. Then the oxes ontining the ords were removed nd lmped overnight in lolly mde mnul lmp. Following the 24 hours setting period, the ords were refully relesed from the moulds, misted with wter nd wrpped in ellophne to enhne hydrtion.the ords were then rked vertilly t mient room temperture nd left to ure for 28 dys. Testing the Physil nd mehnil properties Density ws determined ording to DIN, EN E. Moisture ontent ws determined ording to (ASTM 137). Thikness Swelling (TS) nd wter sorption (WA) for two nd twenty four hours were rried out s speified y the Europen stndrds (EN 313:1993) nd (EN 324-1:1993). The speimens for stti ending test were prepred nd tested ording to the Amerin Stndrd for Testing nd Mterils (ASTM D-137) with some modifitions due to the limited size of ords. The dimensions of the speimens were 2m x m x 1 m. The spn ws 23 m. The test ws rried out using Lloyd testing mhine nd modulus of repture (MOR) of ement nd men ending strength (MOR) were ordingly omputed. Sttistil Anlysis Anlysis of vrine (ANOVA) nd Dunn s Multiple Rnge Test were onduted to study the signifine of the differenes etween tretments using Sttistil Anlysis System (SAS) institute In. (199). RESULTS nd DISCUSSION Physil properties Tle 2 shows the overll mens of wter sorption (WA) nd thikness swelling (TS) four ement onded prtileord under four different ement/lignoellulosi mterils rtios C/LCM). 46

4 J.S. Teh 12(3) 211 Tle 2. Men Wter Asorption (WA) nd Thikness swelling (TS) vlues for ement onded prtileords for ll sets of ord types y ement/lignoellulosi mterils (C/LCM) rtio. WA (%) WA (C/LCM) M.C.% Density TS 2 (%) TS 24 (%) Rtio g/m (%) 2.: : : : The men vlues for thikness swelling deresed with the inrese of ement/lignoellulosi mterils rtios (C/LCM), (Tle 2). The highest vlues were oserved with the 2.:1 rtio nd the lowest were seen with the rtio of 4:1. These figures show tht the properties of dimensionl stility of ll the rtios of ement onded pnels suh s men wter sorption perent (WA %) nd thikness swelling perent (T S %) vlues for oth the 2-hours nd the 24- hours wter soking test onform fvorly to figures reported in pst studies. (Bdejo,1989), ompiled verges tht rnged from 32.9% to 46 % nd.3% to.47% for wter sorption nd thikness swelling tests, respetively. Prestemon, (1976), reported men wter sorption rnge vlues of 28.1% to 6.8 % for 2 mm thik ement onded prtileords following 24 hours soking in old wter. Tle 3 shows the minimum nd mximum vlues of wter sorption (W A) nd thikness swelling (TS) for the different ord types. It is ler from the tle tht the minimum wter sorption of ll ord types nd rtios ws 12.2% ttined y ord (M6) of the ement wood rio 4:1 nd the mximum (WA) ws 43.8% ttined y ord (M8) of the ement/wood rtio 2.:1. The minimum thikness swelling for ll ord types nd rtios ws.42% ttined y ord (M7) f the wood ement rtio 4:1 nd the mximum thikness swelling ws13.% ttined y ord type of the wood ement rtio 2.:1 Tle 3. Minimum nd mximum vlues of wter sorption (WA) nd thikness swelling (TS) for the different ord types y ement/wood (C/W) rtio C/W Rtio Min.W A 2 % Mx,W A 2 % Min. WA 24 % Mx.W A 24 % Min. TS 2 % Mx. TS 2 % Min. TS 24 % Mx. TS 24 % 2.: (M8) (M8) * 3: (M9) (M9) (M9) 1..6 (M9) 3.: (M7) (M) 4.3 4: (M6) (M4) (M4).42 (M7) 1.67 (M4).91 (M7) 2.1 (M7) Figures in prentheses re ord types orresponding to wter sorption nd thikness swelling vlues. The nlysis of vrine for wter sorption nd thikness swelling for oth the 2 hours nd 24 hours tests were highly signifint (P = 1) for ll mixes nd rtios.for the men seprtion test nd Dunn s group of some properties. (figures 1-8). 47

5 J.S. Teh 12(3) 211 CBP/Rtio 2.:1 WA2% d d d Bord types d d e Figure 1. Men vlues of wter sorption fter two hours (WA 2 ) for different ord types of ement onded prtileord (CBP), t ement/lcm rtio 2.:1. Brs with the sme letters re not signifintly different CBP/Rtio 2.:1 TS 24% Bord types Figure 2. Men vlues of Thikness Swelling fter twenty-four hours wter soking (TS24 %) for ement onded prtileord (CBP), t ement/lcm rtio 2.:1. Brs with the sme letters re not signifintly different. 48

6 J.S. Teh 12(3) 211 WA 2% CBP/ Rtio 3:1 d d Bord types Figure 3. Men vlues of Wter sorption perent fter two hours wter soking (WA2%) for ement onded prtileord (CBP) types t ement/lcm rtio 3:1 Brs with the sme letters re not signifintly different. CBP Rtio 3:1 Thikness swelling % f de d de e de Bord types Figure 4. Men vlues of thikness swelling fter twenty four hours wter soking (TS24%) for ement onded prtileord (CBP), t ement/lcm rtio 3:1. Brs with the sme letters re not signifintly different. 49

7 J.S. Teh 12(3) 211 WA 2 (%) d CBP/Rtio 3.:1 d 1 Bord types Figure. Men vlues of Wter sorption perent fter two hours wter soking (WA2 %) for ement onded prtileord (CBP) types t ement/lcm rtio 3.:1. Brs with the sme letters re not signifintly different. TS24% CBP/Rtio 3.:1 Bord types Figure 6. Men vlues of thikness swelling fter twenty four hours wter soking (TS24%) for ement onded prtileord (CBP), t ement/lcm rtio 3.:1. Brs with the sme letters re not signifintly different.

8 J.S. Teh 12(3) 211 WA 2 % d e CBP/Rtio 4:1 e de d de Bord types Figure 7. Men vlues of Wter sorption perent fter two hours soking (WA2%) for ement onded prtileord (CBP) types t ement/lcm rtio 4:1. Brs with the sme letters re not signifintly different CBP/Rtio 4:1 TS24% Bord types Figure 8. Men vlues of Thikness swelling perent fter twenty - four hours wter soking (TS 24 %) for ement onded prtileord (CBP) t ement/lcm rtio 4:1. Brs with the sme letters re not signifintly different. Modulus of rupture (MOR) Averge vlues of modulus of rupture (MOR) for ement onded prtileords nd Dunns grouping re shown in figures 9, 1, nd 11.The verge MOR vlues of the rtio 3:1 re generlly higher thn the verge vlues of the rtios 3.:1 nd 4:1. This result is in greement with findings reported y Moslemi nd Pfister (1987). They indited tht ll MOR vlues re inversely relted to ement / wood rtio in the se of type 1 ement (Ordinry Portlnd Cement). The MOR of 1 % sunt wood-ement ords of the rtio 3:1 surpssed ll other ords in ll rtios used. The MOR of sunt-ement mixture of the rtio 3:1 ttined n verge vlue of Kg/m 2 (1.12 MP) whih ws the highest mong ll the ords mde in ll rtios. This MOR vlue ompres fvorly with pst reserh results. Sudin nd Irhim (1989) reported tht the Mlysin stndrd 1

9 J.S. Teh 12(3) 211 (MS934) speifies minimum requirement of 9. MP for ending strength. It ws oserved tht the ords with high proportions of sunt wood in the mixture ttined higher MOR vlues in omprison to other mixtures. The MOR vlues in the rtios 3.:1 nd 4:1 of ll ord types re generlly low. This my e due to the higher ement /wood rtios nd the use of lium hloride. It ws reported y some reserhers tht redution of the ement to wood rtio inresed the ending strength Moslemi nd Pfister (1987) nd when lium hloride ws used lower ending strength ws oserved (Sudin nd Irhim, 1989). The ords mde of 1 % suntement mixture in these rtios still hold onto the led for MOR vlues. The nlysis of vrine for MOR of ll set of ords nd with ll rtios is highly signifint t (.1) level of proility CBP/Rtio 3:1 MOR (kg/m2) Bord types Figure 9. Men vlues of modulus of rupture (MOR) of ement onded prtileord (CBP) mde from mixtures of ement nd lignoellulosi mterils t ement/lcm rtio 3:1. Brs with the sme letters re not signifintly different. MOR (Kg/m2) CBP/Rtio 3.:1 Bord types Figure 1. Men vlues of modulus of rupture (MOR) of ement onded prtileords (CBP) mde from mixtures of ement nd lignoellulosi mterils t ement/lcmod (C/W) rtio 3.:1. Brs with the sme letters re not signifintly different. 2

10 J.S. Teh 12(3) 211 MOR (Kg/m2) CBP/Rtio 4:1 Bord types Figure 11. Men vlues of modulus of rupture (MOR) of ement onded prtileords (CBP) mde from mixtures of ement nd lignoellulosi mterils t ement/lcm rtio 4:1. Brs with the sme letters re not signifintly different. CONCLUSION * Cement-onded prtileord n e mde from the three lignoellulosi mterils either pure or mixed in different proportions fter wek lklitretment nd ddition of Clium hloride s n elertor. Generlly the highest wter sorption nd thikness swelling vlues of ement-onded prtileords were lwys ssoited with ords hving high proportions of gsse prtiles. The lowest wter sorption nd thikness swelling vlues of ement onded prtileords were lwys ssoited with ords of high proportions of sunt swdust prtiles. The ement / wood rtio (3:1) ttined generlly the highest Bending strength (MOR) vlues ompred to the other rtios tested (3.:1 nd 4:1) espeilly with sunt swdust. Thikness swelling perent (TS %) generlly dereses with the inrese of ement /wood rtio. Referenes 1. Anonymous (1988). Worlds pnel setor ontinues to expnd. World Wood, 29 : Suiynto, B. nd S. Kwi (1996). Rpid prodution of thermosetting ement onded prtileord y stem injetion pressing. Proeedings of the First Interntionl Wood Siene Seminr, Kyoto, Jpn, p Fernndez E. C. nd V. P.Ti-on (2). The use nd proessing of rie strw in the mnufture of ement onded fierord. In: Proeedings of Wood-ement Composites in the Asi Pifi Region. A workshop held t Cnerr, Austrli, pp Evns, P. D. (2). Summry: An introdution to wood - ement omposites. Wood ement omposites in the Asin region. In: Pro. of Workshop held t Rydges Hotel, Cnerr, Austrli,pp Euseio, D. A. (23). Cement onded ords: Tody s lterntive. Pper presented t tehnil forum in elertion of the 21 Philippine Counil for Industry nd Energy Reserh nd Development Anniversry, Dept. of Siene nd Tehnology, held t Eds Shngri-L, GDSA,Psig City, Philippines, 9 pp. 6. Kumr, S. (198). Development of wood wool ords from indigenous mterils. PL-48 Projet. 3

11 J.S. Teh 12(3) 211 Finl Reserh Report, Forest Reserh Institute nd College, Dehr Dun, Indi Sndermnn,W. H., J. Preusser, nd W. Shweers. (196). Studies on minerlonded wood mterils. Holzforshung mterils; the effet of wood extrtives on the setting of ement- onded wood. Berlin, Holzfor shung 14: Sndermnn, W., nd R. Kohler (1964). Studies on minerl onded wood mterils VI.A short test of the ptitude of woods for ement onded mterils. Holzforshung, Berlin, 18 : Simtupng, M. H. (1979). The wter requirement of mnuftured ement onded prtileord. Holz Roh- Werkst. 37: DIN, EN 323.(1993) E. Wood Bsed pnels; Determintion of density, Europen Committee for Stndrdiztion.CEN.Centrl Seretrit:rue de stssrt 36, B- 1, Brussels. 11. Amerin Soiety for Testing nd Mterils (ASTM). (1989). Stndrd methods of evluting the properties of wood-sed fier nd pnel mterils. ASTM, D , Phildelphi, P, USA. 12. EN312: (23). Prtileord Speifitions; Europen Committee for Stndrdiztion, CEN.Centrl Seretrit:rue de stssrt 36, B- 1, Brussels. 13. EN324-1, (1993). Wood Bsed Pnels; Determintion of dimensions of ords, Prt-1: Determintion of thikness, width nd length, Europen Committee for Stndrdiztion, CEN. Centrl Seretrit:rue de stssrt 36, B- 1, Brussels. 14. SAS Institute In.(199). SAS /STAT Guide for personl Computers Version 6 Edition SAS Institute In., Cry, N.C. 1. Bdejo, S.O.O. (1989). Influenes of pretretment temperture nd dditive onentrtion on the properties of ement onded prtile ord from plnttion- grown tropil hrdwoods, Tropil siene. 29: Prestemon, D. R. (1976). Preliminry evlution of woodement omposites, Forest Produts Journl 26: Moslemi, A. A. nd S.C. Pfister (1987). The influene of ement- /wood rtio nd ement type on ending strength nd dimensionl stility of wood-ement omposite pnels. Wood nd Fier Siene 19 : Sudin, R. nd W. A. Irhim (1989). Cement onded prtileord from Ai mngium: A preliminry study. Journl of Tropil Forest Siene 2 (4):

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