ABSTRACT

Soybean oil is among the most abundant, biodegradable, renewable and sustainable vegetable oil

in Nigeria that is rich in polyunsaturated fatty-acids, which earned a good candidate for

epoxidaton. However, the epoxidized soybean oil (ESO) alone lacks good thermo-mechanical

properties. Therefore, ESO is synthesized, thermally pre-cured and finally cured with

polystyrene to obtain a blend of good thermo-mechanical properties. The soybean oil sample was

subjected to FT-IR spectroscopy to determine the characteristic bands of functional groups, and

then analyzed to determine the number of carbon-carbon double bond(s) present in 100g of the

oil sample. The result indicated 149.8 as the iodine number. The resultant/determined number of

carbon-carbon double bonds was interpreted in terms of molar equivalent and then

stoichiometrically combined with peracetic acid (formed in-situ) to yield 9.77% oxirane-oxygen

content of the soybean epoxy resin. The resin was subjected to Fourier Transform Infra-Red (FT-

IR) spectroscopy within the frequency range of (400-4000) cm-1. The observable peaks showed

a characteristic band of 843cm-1, 823cm-1 903cm-1 corresponding to internal, external and

terminal oxirane-oxygen rings respectively, with disappearance at peak 3008 and 914 cm-1 at

cis- and trans-, di-substituted olefins in soybean oil sample. The epoxidized soybean oil (ESO)

was cured thermally to yield a gel coded as modified epoxidized soybean oil (MESO). The

MESO was subjected to FT-IR, and the characteristic bands obtained indicated 3400cm-1and

above. The MESO was blended with polystyrene in the ratio of 10/0, 9/1, 8/2, 7/3, 6/4, 5/5, 4/6

PS/MESO respectively. The mechanical properties of the blend were studied and the results

indicated that 6/4 blend of PS/MESO gave highest values of tensile strength (4.3 x 105 Nm-2)

and Young‘s modulus(14.9 x 105 Nm-2) and a lower value of elongation at break 29%.

Viscometric study of the blends were carried out and the results affirmed that the blend at 6/4

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CHAPTER ONE

1.1       INTRODUCT