THE 28TH CONFERENCE OF THE FEDERATION OF ENGINEERING ORGANIZATIONS

THE 28TH CONFERENCE OF THE FEDERATION OF ENGINEERING ORGANIZATIONS

THE 28 TH CONFERENCE

OF THE FEDERATION OF ENGINEERING ORGANIZATIONS CAFEO 28 HANOI VIETNAM, 30 TH NOV - 2 ND DEC., 2010

TITLE:

POLYSTYRENE BONDED BOARD (PBB)

(Please see separate sheet for the photo)

AUTHOR(S)’

NAME(S):

Engr Mary Lynn G Magbanua Engr Rodolfo B Solomon

ORGANIZATION

& DESIGNATION:

Faculty Members, Sultan Kudarat State University – Isulan Campus, Isulan, Sultan Kudarat, Philippines

ADDRESS: SKSU-Isulan Campus, Isulan, Sultan KUdarat

EMAIL:

marylynnmagbanua@yahoo.com

rudybsolomon@yahoo.com

ABSTRACT: Polystyrene is one of the most ubiquitous plastics of our time Made from highly

refined petroleum and found in the casings of computers Polystyrene foam and other related

disposable polystyrene plastics represent a hazard to the environment

These wastes materials can be recycled and turned into a binder of another waste material –

the rice hull These polystyrene bonded boards (PBB) can be used as a substitute to building

materials such as plywood

Three volumetric ratios of rice hull and polystyrene were fabricated to assess its potential

suitability in the manufacture of PBB by manufacturing test composites of various types

Results showed that PBB has low water absorption, low thickness swell, and high in

flexural strength which means that the less water absorption, the less the deterioration of the board

I INTRODUCTION

Global concerns on environmental problems have been on the rise One major contributor

to these problems is the solid wastes generated by populace Solid waste products such as

disposable polystyrene foam and other agricultural by- products represent a hazard to the

environment

Polystyrene is one of the most ubiquitous plastics of our time Made from highly refined

petroleum and found in the casings of computers, in disposable cutlery, in yogurt containers and

CD jewel cases as well as in countless other applications hundreds of thousands of tons of

polystyrene are produced for our throw-away society

Rice hull is a waste product of rice milling It is generated during the first stage of milling

when rough rice is husked (Lange, 2000) It comes in great volume and usually considered to

contribute to the environmental problems when dumped or burned (Smajilla, 2000) Latest statistics

show that more than 150 million tons of rice hulls are generated each year worldwide

Studies show that rice can be useful in the fabrication of boards and other construction

materials because of its high silica components such as lignin, cellulose and hemicellulose

(Shieh-Lieh, 2000), Because of its high fiber, silica and lignin, (Olivier, http://www

Esria.com/pdf/The-Rice-Hull-House.PDF) rice hull resist fungal decomposition and water penetration and was found

out to have insulating properties

Agro waste materials are very abundant in Sultan Kudarat Agro wastes such as rice hulls

and palm fronds abound in the said province Oil palm fronds fibers are utilized and developed by

converting it to fiber based materials (http//www.aseansec.org /7011html.)

These waste materials can be recycled and turned into a binder of another waste material

which is the rice hull

Adoption of these materials will be beneficial to the builders This Polystyrene Bonded

Boards (PBB) can be used as substitute to building materials such as plywood which is cheaper in

the construction industry This will also help to decrease the continuous rising cost of housing

materials Also, it will lessen the use of wood that causes widespread deforestation

The basic aim is to make a polystyrene bonded board (PBB) out of the agro waste materials

commonly found in the locale It tested the compatibility of the polystyrene binder mix with rice

hull

The physical property of the board such as density, thickness swelling, and water

absorption at different volumetric ratio was measured Also the flexural strength of the board at

different volumetric ratio in three were tested using the Universal Testing Machine (UTM) at the

Department of Public Works and Highways Laboratory (DPWH)

II METHODOLOGY

The materials used in the production of polystyrene bonded boards (PBB) are rice hull,

polystyrene and binder called acrylic thinner

Polystyrene was collected, cleaned and shredded to the desired size for ease of mixing A polymer was mixed to dissolve the polystyrene The dissolved polystyrene was used as binder for the rice hull

Binder Mix

The binder was a mixture of lacquer thinner as dissolving agent and polystyrene using a 60:40, 70:30 and 80:20 for the three (3) mixtures with three replicates for each ratio

Table 1 Mix proportion of binder and rice hull

ID no Binder/

Particle ratio

Binder (g)

Particle Rice hull(g) PBB

6040

60:40 60 40

PBB

7030

70:30 70 30

PBB

8020

80:20 80 20

The specimens with dimensions of 0.02 cm by 0.15cm by 0.30cm was cast in mold and allowed to dry in room temperature for one week Then it was subjected to curing method

The F –test was used in finding out if there is a significant difference in terms of flexural strength Further, it was tested using the Duncan Multiple Range Test (DMRT)

Melting of Polystyrene

Melted polystyrene used as binder

Mixing of binder and rice hull

III RESULTS AND DISCUSSION

The following tables present the results of the compressive tests of the samples from the Universal Testing Machine (UTM) and the statistical analysis performed on the data gathered It also presents the interpretation of the results of the analysis

Table 2 Water Absorption by Water Immersion Treatment of PBB

Treatment/

Volumetric

Ratio

Replicates Weight

(g)

Water Absorption

%

Average Water Absorption (%)

Ww Dw

PBB 60:40

0.08

PBB 70:30

0.023

PBB 80:20

0.045

Results for the water absorption of PBB by soaking are 0.023, 0.045 and 0.08 for volumetric ratio 70:30, 80:20 and 60:40 respectively Using the JIS standards for boards which

is <50% all the three treatments revealed a low water absorption; thus passing the JIS 1408 allowable value of <50%

Table 3 Thickness Swell by Water Immersion Treatment of PBB

Treatment/

Volumetric

Ratio

Replicates

Thickness

%

Average Swell (%)

Before Soaking

After Soaking

Shown in Table 3 are the findings on the thickness swelling by soaking are 0.06, 0.06 and 0.14 for volumetric ratio 70:30, 80:20 and 60:40 respectively Of the three volumetric ratios the board 70:30, 80:20 that contained the least amount of rice hull has the lowest thickness All the three treatments did not passed the allowable thickness swell of <2% set by Japan International Standard for boards The implication could be that rice hull swells when immersed in the water thus, the boards are recommended for interior walls

Table 4 Density of Water Immersion Treatment PBB

PBB 60:40

0.14

PBB 70:30

0.06

PBB 80:20

0.06

Treatment/

Volumetric

Ratio

Replicates Before

Soaking

After Soaking

Density

%

Average Density (%)

PBB 60:40

0.27

PBB 70:30

0.086

PBB 80:20

0.12

The findings on the density of the board showed that 60:40 had the greatest density of 0.27 and the lowest value for 70:30 of 0.086

Table 5 Flexural Strength by Water immersion Treatment of PBB

Treatment/

Volumetric

Ratio

Replicates Flexural

Strength

Average Flexural Strength

PBB 60:40

1 0.00000654

0.00000871

2 0.00000980

3 0.00000980

PBB 70:30

1 0.0000163

0.0000142

2 0.0000131

3 0.0000131

PBB 80:20

1 0.0000229

0.0000229

2 0.0000196

3 0.0000261

The findings on the flexural strength of the board showed that 60:40had the lowest flexural strength of 0.00000871 and the greatest value for 80:20 of 0.0000229 This implies that the lesser the rice hull the greater is the flexural strength This implies that the three treatments did not passed the WWCB standard value of 15 MPa

Table 6.ANOVA table for Water Absorption by Water Immersion Treatment

Since Fc is less than Ft the null hypothesis is accepted Therefore there is no significant difference between the means of the water absorption of the boards using the method of water immersion This implies that all can be used but the least value is highly recommended

Table 7.ANOVA table for Thickness Swell by Water Immersion Treatment

Since Fc is greater than Ft the null hypothesis is rejected Therefore there is a significant difference between the means of the thickness swelling of the boards using the method of water immersion

Source of Variation SS df MSS

F-test value

Fc Ftab 5% 1%

Between Column 0.33 2 0.165

Within Column 2.29 6 0.382

Total 2.62 8 0.33

0.432 5.14 10.92

Source of Variation SS df MSS

F-test value

Fc Ftab 5% 1%

Between Column 8 2 4

Within Column 1.5 6 0.25

Total 9.5 8 1.1875

16 5.14 10.92

Table 7.1.DMRT table for Thickness Swell by Water Immersion Treatment

Treatment 60:40 70:30 80:20

Mean 3.5 a 1.5 ab 1.5 ab

Note: means followed by the same superscript are not significantly different at 1% level of significance

This implies that all can be used but the least value is highly recommended

Table 8 ANOVA table for Density by Water Immersion Treatment

Since Fc is less than Ft the null hypothesis is accepted Therefore there is no significant difference between the means of the density of the boards using the method of water immersion

Source of Variation SS df MSS

F-test value

Fc Ftab 5% 1%

Between Column 000001 2 0.0000005

Within Column .0000152 6 0.00000253

Total 0.0000162 8 0.00000203

0.198 5.14 10.92

Table 9.ANOVA table for Flexural Strength by Water Immersion Treatment

Since Fc is less than Ft the null hypothesis is accepted Therefore there is no significant difference between the means of the flexural strength of the board using the method of water immersion Flexural strength which has the greatest value is recommended

IV CONCLUSION AND RECOMMENDATION

Conclusions

From the findings stated above, the most acceptable mixture is PBB 70:30 because of its low water absorption, low thickness swell, and high in flexural strength which means that the less water absorption the less the deterioration of the board

As large amount of rice hull and polystyrene are found in many parts of the Philippines, there exists an excellent opportunity in fabricating boards towards a wide array of applications in building and construction such as boards and blocks Natural fiber such as rice hull can be a potential candidate in making of composites

Recommendations

Based on the findings the following recommendations are made:

1 A study PBB should include the volume of thinner

2 Further study on tests such as the insulating capability and combustion of the PBB

3 There should be an advocacy for adoption and propagation of the technology on the use agricultural wastes and other plastic materials that are considered as garbage materials

4 Further investigation for improving the properties of boards made from rice hull and polystyrene that should include simple approaches, such as adjusting the binder ratio

Source of Variation SS df MSS

F-test value

Fc Ftab 5% 1%

Between Column -3.15x10-11 2 -1.575x10-11

Within Column -1.52x10-05 6 -2.53x10-06

Total -1.52x10-05 8 -1.9x10-06

6.22x10-6 5.14 10.92

BIBLIOGRAPHY Journals

Beltran, G (2008) Development of Particle Board Using Coffee and Peanut Hulls with Melted Polystyrene as Binder REDTI Journal Vol IV, Diliman, Quezon City

Chaisupakitsin M and Apichatsopit, T (2000) The Role of Recycled Waste Polystyrene Foam on Physical and Mechanical Properties of Novel Ceiling Boards, Department of Chemistry, Faculty of Science, King Mongjut’s Institute of Technology Lad Krabang Bangkok Thailand

10520

Sta.Maria,A.C.et al (1988) General Statistics Text/Workbook, Second Edition Kalayaan

Press Marketing International, Inc.P117

Internet Sources

http//www.adminrecords.uscd.edu/ppm/docs/520-4.html Accessed October 09, 2009

(http//earthsource.org) Accessed November 16,2008

September 02, 2009

(http//www.aseansec.org/7011html.) Accessed June 15, 2008

(http://search.yahoo.com/search;_ylt=A0oGkkX5StNItiAANAhXNyoA?p=thinner&y=Search&fr=

fptb-msgr&ei=UTF-8&fp_ip=PH&rd=r1&meta=vc%3Dph)

OHAMA YOSHIHIKO; MORI IPPEI, Polystyrene Composite Using Chaff as Aggregate and Its Preparation Method Accessed June 18, 2009

(http://en.wikipedia.org/wiki/Japanese_Industrial_Standards) Accessed March 22, 2010

Accessed March 22, 2010

PICTURE OF AUTHORS

ENGR RODOLFO B SOLOMON

ENGR MARY LYNN G MAGBANUA