EFFECTS OF TEMPERATURE PARAMETERS ON THE PREPARATION OF CARBOXYMETHYL CELLULOSE ISOLATED FROM ZEA MAYS

Cellulose powders were successfully isolated from de-grained maize cob powders using acid and alkali hydrolysis for the delignification of the cellulosic material. This isolation using 25g of maize cob gave 10g of cellulose, yielding about 40% of this important polymer. The isolated cellulose powder was carboxymethylated for single and multistep processes for three times successively with varied temperature and a constant pH 10. The carboxymethylation process involved using Monochloroacetic acid and sodium hydroxide as the etherifying agents. The carboxymethylation reaction was optimized against reaction temperature and reaction time. The degree of substitution (DS) obtained was 0.2 at 40°C and it was observed that as the temperature increased, DS value increased until a maximum value of 0.46 at 60°C. Carboxymethylation improved the free swelling capacity of native cellulose isolated from maize cobs.

TABLE OF CONTENTS

CHAPTER ONE

• Introduction

1.1       Cellulose

1.2       Natural Sources of cellulose

1.3       Structure and properties of cellulose

1.3.1    Swelling of cellulose

1.4       Uses of cellulose

1.5       Maize cobs

1.6       Uses of maize cobs

1.7       Aims and objectives

CHAPTER TWO

• Literature review

2.1       Overview of cellulose

2.2       Cellulose content of some agricultural wastes

2.3       Composition of maize Cob

2.4       Chemical modification of cellulose

2.4.1    Etherification

2.5       Carboxymethyl cellulose

2.6       Molecular structure of CMC

2.7       Functionality

2.8       Preparation of carboxymethyl cellulose (CMC)

2.9       Properties of carboxymethylcellulose

2.9.1    Properties of CMC in aqeous solution

2.9.2    Viscosity measurement of CMC

2.9.3    Rheological behaviour of CMC solution

2.9.4    Adsorption of carboxymethyl cellulose

2.9.5    Application of carboxymethyl cellulose

CHAPTER THREE

• Materials and methods

3.1       Materials

3.2       Apparatus

3.3       Isolation of cellulose from maize cob

3.4       Percentage yield

3.5       Preparation of CMC

3.6       Determination of degree of substitution

3.7       Determination of free swelling capacity

3.8       Determination of moisture content

3.9       FT – IR spectroscopy

CHAPTER FOUR

• Results and discussions

4.1       Percentage yield of cellulose

4.2       Effect of reaction time on yield

4.3       Degree of substitution (DS) of CMC

4.4       Free swelling capacity (FSC)

4.5       Effect of pH on CMC solution

4.6       Effect of reaction temperature on DS

4.7       Effect of reaction temperature on DS

• Moisture content

4.9 Conclusion

REFERENCES