Tiger Grass Pollen as a Potential Insulation Board Material

Tiger Grass Pollen as a Potential Insulation Board Material

Reynaldo P. Ramos

^1,2,3

and Jona Val T. Casidsid

⁴

ABSTRACT

Tiger Grass (Thysanolaena maxima) pollen is disregarded as a valuable agricultural waste; thus, this study investigates its potential and beneficial uses as an alternative building insulation material with arrowroot starch as binder. Samples were prepared in varying mix proportions by weight of the tiger grass pollen, water, and arrowroot starch as binding agent. Three different sample mixtures were prepared into particleboards with thickness ranges from 8 mm to 10 mm and air-dried for 10 days. These particle boards were tested for acoustics, thickness swelling, water absorption and thermal conductivity. Based on the tests conducted, mixtures B – 250 grams - tiger grass pollen and 125 grams - arrowroot starch which is equivalent to 50% of the tiger grass pollen weight; and mixture C: 250 grams - tiger grass pollen with 150 grams - arrowroot starch which is equivalent to 60% of the tiger grass pollen weight demonstrated acceptable results having met the allowable limit values or minimum standards set for the properties used.

Keywords: tiger grass pollen, insulation material, particle board, building construction, civil engineering

INTRODUCTION

Tiger gra ss (Thysanolaena maxima) is one of the most cultiva ted gra sses loca lly grown in the Philippine s a nd it looks like ba mboo a nd suga rca ne. Tiger gra ss has a va riety of uses a nd it pla ys a va lua ble role a s the ma in ma teria l for broom production. The ba mboo-like sta lks ma ke strong ha ndles a nd the dried flower pa nicles a re tied together to ma ke the broom pa rts. The fibers (pa nicles) of this pla nt a re a lrea dy proved its importa nce a nd life spa n beca use it is being used in ha ndicraft production tha t is why this fiber performs certa in strength tha t could resist loa ds a pplied into it.

One of the most importa nt cha llenges of future buildings is the reduction of energy consumptions in a ll their life pha ses - from construction to demolition.

Through tha t, building insula tions were developed a nd commonly rea lized using ma teria ls obta ined from petrochemica ls (ma inly polystyrene) or from na tural sources processed with high energy consumptions (gla ss

a nd rock wools). These ma teria ls ca use significa nt detrimenta l effects on the environment mainly due to the production sta ge like use of non-renewa ble ma teria ls a nd fossil energy consumption, a nd to the disposa l sta ge like problems in reusing or recycling the products a t the end of their lives.

Due to other problems brought a bout by clima te cha nge, the use of therma l insula tion ma teria ls susta ins the comforta ble tempera tures in living environments or in building which beca me ra mpant in recent yea rs. The use of therma l insula tion is rega rded a s one of the most energy-efficient improvements a nd mea ns of energy conserva tion in buildings. As the la rgest buildin g component, it pla ys a n importa nt role in a chieving buildings’ energy efficiency. This will result in decrea sing the cost of cooling a s well a s decrea sing the pollution of the environment. Ta lking a bout energy consumption, both commercia l a nd residentia l buildings spent a lmost ha lf of prima ry energy resources a nd trend to increa se in the future.

Pa rticleboa rds a re rela tively new type of engineered wood product tha t a re ma de from gluing together sma ll chips, sa wdust, sa w sha vings, recycled wood, a gricultura l residue, etc. Pa rticleboa rd is a wood - ba sed composite tha t is used for ma ny a pplica tions such a s furniture, flooring, pa nels, a nd the likes (S. Khosra vi 2011, unpublished thesis). Pa rticleboa rds consist of wood pa rticles glued together a t high tempera ture and pressure. The pa rticles a re sepa ra ted ba sed on size a fter they ha ve been dried, the sizes of the pa rticles a re of grea t importa nce a nd will influence the properties of the fina l product. Norma lly, pa rticleboa rds ha ve three la yers na mely (a ) core la yer with coa rser pa rticles a nd a lowe r density, a nd (b) two surfa ce la yers with finer pa rticles

rsu.rpramos2020@gmail.com

1College of Engineering and Technology, Romblon State University, Odiongan, Romblon, Philippines

2Graduate Education and Professional Studies, Romblon State University, Odiongan, Romblon, Philippines

3International Linkages and External Affairs, Romblon State University, Odiongan, Romblon, Philippines

4Department of Interior and Local Government, Odiongan, Romblon, Philippines

Received 28 October 2020; Accepted 06 July 2021; Available online 23 July 2021

a nd higher densities. The Austra lia n Sta nda rd (AS/NZS 1859) gives limit va lues for certa in mecha nica l a nd physica l properties [Engineered Wood Products Associa tion of Austra la sia (EWPAA), 2008]. Ta ble 1 shows the typica l va lues of these properties (ra ther than limit va lues) presented in 3 thickness cla sses.

Ta ble 1. Property Va lues for Sta nda rd Pa rticleboa rd (EWPAA, 2008)

Property Unit Thickness Class - mm

≤12 13 - 22 >23 Density kg/m³ 660 - 700 660 - 680 600 - 660 Bending Strength

(MOR) MPa 18 15 14

Bending Stiffness

(MOE) MPa 2800 2600 2400

Internal Bond

Strength MPa 0.6 0.45 0.40

Surface Soundness MPa 1.25 1.30 1.30 Screw Holding -

Face N - 600 700

Screw Holding -

Edge N - 700 750

Thickness Swell (24

Hr) % 15 12 8

Formaldehyde E1

(Desiccator Method) mg/l 1.0 –1.5 1.0 –1.5 1.0 –1.5

Ma ny resea rch studies ha ve experimented va rious a lterna tive ma teria ls from a gricultura l wa stes with empha sis on finding new ma teria ls for a coustic component pa nels a nd insula tion pa rticleboa rds (Fa ustino et a l., 2012; Pa iva et a l, 2012 Cha roenva i et a l., 2013; Asruba li et a l, 2015; Ta ngjua nk & Kumfu, 2011; Suleima n et a l, 2013). These new a lterna tive susta ina ble sound insula tions building products have been at the center of society’s concerns. For example, sound insula tion products processed with na tu ral ma teria ls such a s cotton, cellulose, hemp, wool, cla y, jute, sisa l, kena f, fea ther a nd coco or processed with recycles ma teria ls like wood, ca nva s, foa m, bottle, jea ns, rubber, polyester, a crylic, fibergla ss, ca rpet, a nd cork a re some solutions a lrea dy esta blished for sound insula tion. Some other residua l wa stes such as newspa per, honeycomb, a nd polymeric wa ste were a lso tested to determine their technica l potentia l. Thus, these green products or eco-products intend to be susta ina ble a lterna tive to the tra ditiona l ones like gla ss or rock wool (Fa ustino et a l., 2012). Pa rticleboa rds ma de of a gricultura l wa stes such a s ba ga sse, cerea l, stra w, corn sta lk, corn cobs, cotton sta lks, rice husk, stra ws, sunflower hulls, a nd lea ves oil were a lso tested for therma l insula tion performa nce (Pa iva et a l., 2012). The ma in goa l of using these a gricultura l wa stes, a side from meeting the cha llenges of disposing such wa stes, is to identify energy-sa ving building ma teria ls with low therma l conductivity to reduce hea t tra nsfer into the building (Cha roenva i, 2013).

In a ddition, previous studies compa red these unconventiona l a nd recycled insula tion ma teria ls ba sed on severa l properties such a s density, thermal conductivity, specific hea t, fire cla ssifica tion, a nd wa ter va por diffusion (Asruba li et a l., 2015). Moreover, other properties such a s a coustic a bsorption, a coustic insula tion, including thickness were eva lua ted. Tests were a lso ca rried out to determine the physica l properties (moisture content, thickness swelling a nd wa ter a bsorption) a nd fire resista nce of these a lterna tive wa ste ma teria ls [(Ta ngjua nk & Kumfu 2011). Previous studies a lso eva lua ted not only the composition of the ma in a lterna tive wa ste ma teria ls but a lso the type of binding ingredient or a dhesive used (Cha roenva i et a l., 2013; Ta ngjua nk & Kumfu, 2011; Suleima n et a l, 2013;

Mouburik et a l, 2010; Sula ima n et a l., 2013; Elba da wi et a l., 2015; a nd Aba yomi et a l., 2015). The type of bonding ma teria ls, pa rticula rly biodegra da ble a nd environmenta lly friendly binders a re importa nt to produce structura lly strong, sta ble, a nd dura ble pa rticleboa rds.

This study wa s conducted to be a ble to produce a n economica l a nd profit-oriented product. This study a lso a imed to produce dura ble pa rticleboa rd as insula tion ma teria ls for structura l a pplica tions from loca lly sourced ma teria ls by using tiger gra ss pollen in conjunction with different na tura l binders. This is in effort to reduce the ra te of importa tion of synthetic fibers a nd ma ke loca lly ma de building ma teria ls a va ila ble at a chea per ra te.

METHODOLOGY

Mix Proportion

Ta ble 2 shows the three mix proportions used in the study. Every sa mple mixture ha s three sa mples indica ting the a mount (in gra ms) of the Tiger Gra ss pollen, a rrowroot sta rch a s binder, a nd wa ter a s the main ingredients for the mix.

Ta ble 2. Mixing Proportion of the Pa rticleboa rds Mixture

No. of Sample

Amount of the Tiger

Grass Pollen(g)

Amount of Arrowroot Starch(g)

Amount of Water Used for Binder

Mixture A

Sample 1 250 100 1 ½ cup

Sample 2 250 100 1 ½ cup

Sample 3 250 100 1 ½ cup

Mixture B

Sample 1 250 125 1 ¾ cup

Sample 2 250 125 1 ¾ cup

Sample 3 250 125 1 ¾ cup

Mixture C

Sample 1 250 150 2 cups

Sample 2 250 150 2 cups

Sample 3 250 150 2 cups

Testing of Acoustical Properties

The testing cha mber wa s fa brica ted with the following dimensions: 0.7m x 0.6m for the ba se a nd 1.0m for its height with a volume of 0.42m³ to a ccord with the specimen a rea of 0.09m². The cha mber is an enclosed spa ce ma de of plywood a nd studs.

The specimen for ea ch mixture were insta lled in the three fa ces of the cha mber, three specimens for ea ch fa ce.

Determination of Peak Amplitude

Loudspea ker is outside the cha mber a t fixed point for a ll types of mixture with va rying frequency and intensity of sound ha ving the microphone probe inside the cha mber. The microphone probe is connected to a ma gnetic ta pe recorder for da ta stora ge a nd future mea surement or reference. The softwa re used in determining the pea k a mplitude wa s Cool Edit Pro which the da ta a re recorded, a na lyzed, a nd summarized.

Determination of Thickness Swelling, Water Absorption and Thermal Conductivity

The determina tion of 2-hour wa ter a bsorption (WA) a nd thickness swelling (TS) tests were performed a ccording to the America n Society for Testing a nd Ma teria ls (ASTM) D-1037. After 2 hours, the uncoa ted/natural a nd coa ted sa mples with pa int were ta ken out from the wa ter a nd reweighed a nd re- mea sured for its thickness. The wa ter a bsorption of each specimen wa s ca lcula ted by the weight difference. The wa ter a bsorption a nd thickness swelling of ea ch specimen were prepa red with a surfa ce dimension of 0.15m x 0.15m a nd ca lcula ted using Equa tions 1 a nd 2.

Where:

ti = initial thickness of the sample tf= final thickness of the sample

Thickness Swelling (TS) is expressed in percentage.

Where:

wi = initial weight (dry) of the sample wf= final weight (wet) of the sample Water Absorption is expressed in percentage

The test for therma l conductivity wa s done in terms of moisture content (MC) a nd dry density of the sa mples. To ca lcula te the therma l conductivity of ea ch sa mple, the formula derived by Sia u (1983) wa s a pplied (TenWolde et a l., 1988). Therma l conductivity is being

computed to determine how much electric current or a mount of hea t the sa mple ca n receive before it yields following Equa tions 3, 4 a nd 5:

Get the moisture content of the sa mple (MC) with a formula of:

MC = ^{𝑊𝑤−𝑊𝑑}

𝑊𝑤 x 100% (3)

Get the dry density of the sa mple (ρ) with a formula of:

ρ = ^{𝑊𝑑𝑟𝑦}

𝑉 (4)

Solve for the therma l conductivity (k) with a formula of:

k = 0.509547 – 0.471983(a ) (5)

Where:

k = thermal conductivity of the sample a = Porosity = √(1− 0.000667D − 0.00001MD M = moisture content of the sample

D = dry density of the sample (kg/m³)

RESULTS AND DISCUSSION

Peak Amplitude Results

Ta ble 3 shows the results of the pea k a mplitude per mixture. Compa ring the result of the three mixtures, Mixture C ha s the lowest pea k a mplitude of -15.68 dB which mea ns the intensity of sound being a bsorbed is low while Mixture A recorded the highest peak a mplitude of -14.01 dB which mea ns there is no effect in the intensity of sound being a bsorbed a s it compa res to the pea k a mplitude recorded by the empty room which is -14.08 dB. Mixture B recorded pea k a mplitude of -15.31 dB.

Thickness Swelling

The determina tion of two-hour thickness swelling (TS) test wa s performed a ccording to ASTM D-1037. After two hours, the specimens which a re uncoa ted/natural a nd coated with pa int were ta ken out of the wa ter for the mea surement of its thickness. The thickness of ea ch specimen wa s ca lcula ted by the thickness difference. The thickness swelling of ea ch specimen wa s prepa red with a surfa ce dimension of 0.15m x 0.15m. Ta ble 4 shows the results for the three mixtures, compa ring uncoa ted or na tura l a nd coa ted with pa int before a nd a fter soa king.

The thickness of the sa mples tha t ra nges from 8mm to 10 mm subjected for testing were considered as thin pa rticleboa rd a ccording to Austra lia n Sta ndard AS/NZS 1859 (EWPAA, 2008). The thickness of the pa rticleboa rd under thin ca tegory ra nges from 0 to 12mm thick. Ta ble 4 shows the thickness swelling of the uncoa ted/natura l a nd coa ted with pa int sa mples.

𝐓𝐡𝐢𝐜𝐤𝐧𝐞𝐬𝐬 𝐒𝐰𝐞𝐥𝐥𝐢𝐧𝐠(𝐓𝐒) = ^tf−ti

t_i x100% (1)

𝐖𝐚𝐭𝐞𝐫 𝐀𝐛𝐬𝐨𝐫𝐩𝐭𝐢𝐨𝐧 (𝐖𝐀) = ^wf−wi

w_i x100% (2)

Ta ble 3. Pea k a mplitude va lues for the different test mixtures.

Amplitude Value Empty Room Mixture C Mixture B Mixture A

Left Right Left Right Left Right Left Right

Min Sample Value: -7513 -6401 -6336 -5389 -5537 -4713 -7332 -6261

Max Sample Value: 7630 6481 6154 5244 6571 5621 7674 6528

Peak Amplitude (dB) -12.66 -14.08 -14.27 -15.68 -13.96 -15.31 -12.61 -14.01 Minimum RMS Power dB) -32.79 -34.19 -33.83 -35.2 -34.89 -36.27 -35.03 -36.39 Maximum RMS Power (dB) -15.74 -17.13 -21.62 -23.01 -21.51 -22.9 -20.51 -21.9 Average RMS Power (dB) -24.71 -26.1 -29.4 -30.78 -29.92 -31.3 -28.91 -30.29 Total RMS Power (dB) -24.26 -25.65 -29.12 -30.5 -29.75 -31.13 -28.59 -29.97

Actual Bit Depth (Bit) 16 16 16 16 16 16 16 16

Ta ble 4. Thickness Swelling (TS) of the Uncoa ted/Na tural a nd Coa ted with Pa int Thickness Swelling (TS) in Percentage (%)

Mixture No. of Samples Uncoated/

Natural Coated with Paint

Average Uncoated/

Natural

Coated with Paint

Mixture A

Sample 1 13 38

12 25

Sample 2 11 33

Sample 3 11 0

Mixture B

Sample 1 11 11

11 11

Sample 2 11 11

Sample 3 11 11

Mixture C

Sample 1 0 22

3 17

Sample 2 0 10

Sample 3 10 20

Ta ble 5. Wa ter Absorption (WA) of the Uncoa ted/Na tural a nd Coa ted with Pa int Water Absorption (WA) in Percentage (%)

Mixture No. of Samples Uncoated/

Natural Coated with Paint

Average Uncoated/

Natural

Coated with Paint

Mixture A

Sample 1 220 153

204 148

Sample 2 200 122

Sample 3 191 169

Mixture B

Sample 1 100 133

111 119

Sample 2 100 88

Sample 3 133 135

Mixture C

Sample 1 146 88

140 107

Sample 2 160 144

Sample 3 113 90

Ta ble 6. Therma l Conductivity of the Sa mples Mixture No. of

Sample

Weight Wet

(g)

Weight Dry

(g)

Dry Density

Kg/m³

Moisture Content

%

Porosity (a)

Thermal Conductivity

W/m-K

Mixture A

Sample 1 125 50 277.78 60 0.9026 0.078

Sample 2 300 75 370.37 75 0.8351 0.111

Sample 3 137.5 68.75 339.51 50 0.8986 0.080

Mixture B

Sample 1 187.5 75 370.37 60 0.7285 0.1626

Sample 2 150 75 370.37 50 0.7535 0.1505

Sample 3 150 75 370.37 50 0.7535 0.1505

Mixture C

Sample 1 150 81.25 401.23 45.83 0.8884 0.085

Sample 2 137.5 75 333.33 45.45 0.9089 0.075

Sample 3 162.5 93.75 416.67 42.31 0.8921 0.083

The percenta ge of thickness swelling of the uncoa ted/natural sa mples a tta ined a va lue which ra nges from 0% to 13% a nd did not exceed the ma ximum percenta ge of thickness swelling which is 15%

a ccording to Austra lia n Sta nda rd AS/NZS 1859 (EWPAA, 2008). On the other ha nd, coa ted with pa int sa mples revea led tha t only Mixture B sa mples a cquired a percenta ge of 11% which did not exceed the sta ndard ma ximum va lue of thickness swelling.

Water Absorption

The determina tion of two-hour wa ter a bsorption (WA) test wa s performed a ccording to ASTM D-1037.

After two hours, the specimens which a re uncoa ted/natural a nd coa ted with pa int were ta ken out from the wa ter a nd reweighed them. The wa ter a bsorption of ea ch specimen wa s ca lcula ted by the weight difference. The wa ter a bsorption of ea ch specimen wa s prepa red with a surfa ce dimension of 0.15m x 0.15m.

The percenta ges of wa ter a bsorption of uncoa ted/natural a nd coa ted with pa int sa mples a re shown in Ta ble 5. For uncoa ted/natural sa mple, Mixture A showed the highest wa ter a bsorption of 220% a nd Mixture B revea led the lowest wa ter a bsorption of 100%. For sa mples coa ted with pa int, Mixture A still got the highest wa ter a bsorption of 169% a nd Mixture C a tta ined the lowest wa ter a bsorption of 88%. By getting the a vera ge percenta ges of wa ter a bsorption for uncoa ted/natural a nd coa ted with pa int sa mple, Mixture B showed the lowest va lue wa ter a bsorption of 115%

a nd it is considered a s good pa rticleboa rd.

Thermal Conductivity

The test wa s done in terms of moisture content (MC) a nd dry density of the sa mples. The surfa ce dimension of the sa mple used wa s 0.15m x 0.15m.

Therma l conductivity is being computed to determine how much electric current or a mount of hea t the sa mple ca n receive before it yields. As shown in Ta ble 6, the ca lcula ted va lue for Mixture C fa irly met the AS/NZC 1859 sta nda rds - 0.075 W/m-K (EWPAA, 2008).

CONCLUSION

This prelimina ry investiga tion wa s conducted to esta blish the potentia ls of Tiger Gra ss pollen a s an a lterna tive building insula tion ma teria l. Ba sed on the findings, Tiger Gra ss pollen ca n repla ce the synthetic fiber in the production of pa rticleboa rds. With the tests ca rried out for a coustic properties, thickness swellin g, wa ter a bsorption, a nd therma l conductivity, Mixtures B a nd C, ha ving the proportion of 250g of Tiger Gra ss pollen a nd 125g of a rrowroot sta rch a s binder, a nd 250g of Tiger Gra ss pollen a nd 150g of a rrowroot sta rch, respectively, showed fa vora ble properties compa red with sta nda rd pa rticleboa rd. Thus, it proved tha t this disrega rded a gricultura l wa ste combined with a rrowroot sta rch ha s a promising potentia l a s a n environmenta lly- a nd eco-friendly substitute for therma l insula tion product. To improve its dura bility a nd resista nce to externa l fa ctors such hea t/fire a nd fungi, it is recommended to conduct more tests to a ddress these issues before a widesprea d use of Tiger Gra ss pollen as the prima ry ingredient in pa rticleboa rd production .

ACKNOWLEDGEMENT

The methods a nd data presented were the results of the undergra dua te thesis under the supervisions of Engr.

Reynaldo P. Ramos, PhD. The thesis entitled “Thermal a nd Acoustic Properties of Tiger Gra ss Pollen Insula tion Ma teria l with ArrowRoot Sta rch a s Binder” wa s submitted by the following fina l yea r civil engineerin g students, na mely: Ca sidsid, Jona Va l T.; Fesa rillo , Cha rma ine F.; Fornea , Donna F.; Ga do, Koen Ka te S.;

Gonza les, Ma ry Joy R.; Pa stor, Sa hra Ma e F.

AUTHOR CONTRIBUTIONS

The conduct of the study wa s done by the fina l yea r civil engineering students, hea ded by Engr. Jona Va l T. Ca sidsid. Engr. Ca sidsid a dministered the entire prepa ra tion a nd testing tiger gra ss pollen insula tion ma teria l. Dr. Reyna ldo P. Ra mos, supervised the

conduct of the study a nd he orga nized the content of the pa per a nd he did the fina l revision of the technica l pa per, highlighting the ma jor findings of the study.

CONFLICT OF INTEREST

The authors declare no conflict of interest.

REFERENCES

Aba yomi, O., Temitope, O., Ola wa le, A. & Oyela yo, O.

(2015). Recycling of Rice Husk into a Loca lly- Ma de Wa ter-Resista nt Pa rticle Boa rd. International Journal of Novel Research in Engineering and Science, 2 (1). 21-30.

America n Society for Testing a nd Ma teria ls (2020).

Standard Test Methods for Evaluating Properties of Wood-Base Fiber and Particle Panel Materials.

https://www.a stm.org/Sta nda rds/D1037.htm Asrubali, F., D’Alessandro, F. & Schiavoni, S. (2015).

A review of unconventiona l susta ina ble building insula tion ma teria ls. Sustainable Materials and Technologies, 4. 1-17.

Cha roenva i, S. (2013). New insulating material:

Binderless particleboard from durian peel in Cha ng, Al Ba ha r& Zha o (eds). Advances in Civil Engineering and Building Materials. Ta ylor &

Fra ncis Group, London.

Elba da wi, M., Osma n, Z., Pa rida h, T., Na sroun. T. &

Ka ntiner, W. (2015). Mecha nica l a nd Physica l Properties of Pa rticleboa rds ma de from Aila nthus wood a nd UF resin fortified by Aca cia s Ta nnins Blend. Journal of Material and Environmental Science, 6 (4). 1016-1021.

Engineered Wood Products Associa tion of Austra la sia (2008). Facts about Particleboard and MDF.

Queensla nd: Austra lia n Wood Pa nels Associa tion Incorpora ted.

Fa ustino, J., Pereira , L., S. Soa res, S., Cruz, D., Pa iva, A., Va rum, H., Ferreira , J. & J. Pinto (2012).

Impa ct sound insula tion technique using corn cob pa rticle boa rd. Construction and Building Materials, 32. 153-159.

Mouburik, A., Alla l, A., A. Pizzi, A., Cha rrier, F., &

Cha rrier, B. (2010). Prepa ra tion a nd Mecha nical Cha ra cteriza tion of Pa rticleboa rd Ma de from Ma ritime Pine a nd Glued with Bio-Adhesive s Ba sed on Cornsta rch a nd Ta nnins. Moderas Cencia Y Technologia, 12(3). 189-192.

Pa iva , A. & S. Pereira , D. Cruz, H. Va rum a nd Pinto, J.

(2012). A contribution to the therma l insula tion performa nce cha ra cteriza tion of corn cob pa rticleboa rds. Energy and Buildings, 45. 274-279.

Sula ima n, N., Ha smim, R., Amini, M., Sula ima n, O. &

Hiziroghu, S. (2013). Eva lua tion of the Properties of Pa rticleboa rd Ma de Using Oil Pa lm Sta rch Modified with Epichlorohydrin, BioResources, 8 (1). 283-301.

Suleima n, L., Aigbodion, V., Shua ibu, L., & M.

Sha nga lo, M. (2013). Development of Eco-friendly Pa rticleboa rd Composites Using Rice Husk Pa rticles a nd Gum Ara bic. Journal of Materials Science and Engineering with Advanced Technology, 7 (1). 75-91.

Ta ngjua nk, S. & Kumfu, S. (2011). Pa rticle Boa rds from Pa pyrus Fibers a s Therma l Insula tion. Journal of Applied Sciences, 11 (14). doi:

10.3923/ja s.2011.2640.2645.

TenWolde, A., McNa tt, J., & Kra hn, L. (1988). Thermal Properties of Wood and Wood Panel Products for Use in Buildings. Oa k Bridge Na tional La bora tory.