Description

ABSTRACT

Thermoplastic starch (TPS) was prepared from blends of natural sweet potato starch and polyvinyl alchohol (PVOH) at varying compositions by gelatinizing and plasticizing it with water and glycerol. The TPS samples were characterized by measuring their melting temperature, glass transition temperature, density and solubility in solvents. Their properties were found to vary with the composition of starch, PVOH and glycerol in the samples. The melting and glass transition temperatures of the TPS increased from 146 ^oC to 167 ^oC and 50.8 ^oC to 71.8 ^oC respectively, with the addition of PVOH. Addition of glycerol however reduced the melting and glass transition temperatures for both the starch-only and starch-PVOH TPS samples. The TPS samples were found to be high density plastics as their densities were greater than that of water. They were soluble in water but resistant to organic solvents. Their properties compared favourably with commercially available polymers.

LIST OF ABBREVIATIONS

Abbreviations	Meaning
Μ	Microns
ASTM	American Society for the Testing of Materials
OC	Celsius
CO2	Carbon Dioxide
CTCRI	Central Tuber Crops Research Institute
EPI	Environmental Crops Inc
FAO	Food and Agriculture Institute
FCI	Fixed Capital Investment
G	Grams
GDP	Gross Domestic Product
HDI	Human Development Index
HDPE	High Density Polyethylene
HMF	Hydroxymethylfurfural
IRR	Internal Rate of return
Kg	Kilogram
LDPE	Low Density Polyethylene
M	Mass flow rate
m3	Cubic metre
Ml	millilitres
MSW	Municipal Solid Waste
NA2S2O5	Sodium Metabisulphite
PBS	Polybutylene Succinate
PCL	Polycaprolactone

 

TABLE OF CONTENTS

COVER PAGE

TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWELDGEMENT

ABSTRACT

GLOSSARY

CHAPTER ONE

1.0      INTRODUCTION

1.1      BACKGROUND OF THE STUDY

• AIM OF THE STUDY
• OBJECTIVE OF THE STUDY
• PURPOSE OF THE STUDY
• SCOPE OF THE STUDY
• PROJECT ORGANISATION

CHAPTER TWO

LITERATURE REVIEW

• INTRODUCTION
• OVERVIEW OF POTATOES
• TYPES OF PLASTICS
• STARCH BASED PLASTIC
• DIFFERENT TYPES OF STARCH SOURCES
• REVIEW OF RELATED STUDIES ON BIOPLASTICS
• REVIEW OF BIOPRODUCTS FROM POTATOES

CHAPTER THREE

3.0      METHODOLOGY

• MATERIALS AND METHODS

CHAPTER FOUR

4.1      RESULT AND DISCUSSION

CHAPTER FIVE

• CONCLUSION
• REFERENCES

CHAPTER ONE

1.0                                                          INTRODUCTION

1.1                                                            BACKGROUND

Basically, plastics can be classified as a group of man-made or natural organic materials that can be molded and then hardened, including many types of resins, resinoids, polymers, cellulose derivatives, casein materials, and proteins

Plastics, made from non-renewable resources such as petroleum products, are now very common and are being used almost everywhere as such; in packing materials, in bottles, cell phones, plastic bags and more. They are being so extensively used because of their durability, strength, malleability, low reactivity and cost efficiency.

However, together with all its benefits is the fact that it is highly pollutant and plastics nowadays have become a big environmental issue.

Nowadays, people are more aware about the harmful effects of petrochemical derived plastic materials in the environment. Researchers have conducted many researches for mmanaging plastic waste on earth by finding eco-friendly alternative to plastics. This ecofriendly alternative is bioplastics, which are disposed in environment and can easily degrade through the enzymatic actions of microorganisms. The degradation of biodegradable plastics give rise to carbon dioxide, methane, water, biomass, humic matter and various other natural substances which can be readily eliminated (Azios, 2007).

Plastic bags has be banned in Mauritius from the 1st January 2016 as Environment Protection (Banning of Plastic Bags) Regulations 2015 have been amended to avoid all confusion around the definitions of plastic and plastic bags. The regulations prohibit import, manufacture, sale, or supply of a plastic bag as from 1st January 2016. The regulations concern only the vest-type plastic bags, roll-on bags and Non-Woven Polypropylene bags, which are designed to carry goods purchased at points of sale such as wholesale and retail outlets, markets, fairs and hawkers. The import, manufacture, sale or supply of biodegradable and compostable plastic bags is allowed subject to strict conformity to appropriate standards specified in the regulations.

There is thus a need for a more sustainable alternative such as bioplastics and this study accounted for the production of bioplastic from potato starch so as to assess its feasibility.

                   Production of plastics

The production of plastic around the world represents over 90 million tonnes and the growth is assessed to be around 3% per year. The worldwide production of plastic has grown by more than five hundred percent during the last 30 years (Plastinum Polymer Technologies Corp, 2009).

Around 6% of the world oil supply is used in the production of plastics and it is mainly used for the plastic packaging and vehicle assembly and in construction (Zawya, 2011). For example in the north of America and the western European countries, the amount of plastic consumed is about 100kg per capita and is estimated to reach 140kg per capita by 2015.

                   Plastic Carry Bags

As per the Environmental Protection Act 2004 governing ‘Plastic Carry Bags’ the plastic carry bag is defined as ‘the vest-type carrier bag made of plastic designed for the general purpose of carrying goods purchased by consumers’ (Ministry of Environment and Sustainable Development, 2004). Most of today’s plastics come from petrochemicals and are not biodegradable. In addition to that, there are depleting reserves of those petroleum resources. Also, incineration of plastics as such is not an appropriate method as there are high toxin emissions such as dioxins and furan, adding to environmental issues. Though plastic recycling has some advantages, it is considered to have a negative impact on our ecosystem as an important amount of energy is required during the recycling phase. Since then, there have been major interests to replace conventional plastics by degradable ones. Results indicated that plastics from renewable sources would degrade in a time frame of 60 days, while those with biodegradable additives would require more time (Mohee et al., 2006). Hence, for the different reasons mentioned, it is clear that biodegradable polymers would add ample to sustainable development.

1.2                                                    AIM OF THE PROJECT

Biodegradable plastics present a potential alternative to petroleum-based plastics. Reducing oil consumption and promoting a greener environment remain an important goal for the sustainably-minded today. This study aim is to investigate the potential of producing bioplastics from potato peels.

1.3                                           OBJECTIVES OF THE PROJECT

The main objectives of this study are:

• To carry out a literature review on plastics and bioplastics
• To investigate the feasibility of local potato as main
• To perform tensile stress, strain, elasticity and young’s modulus test on some bioplastic samples
• To perform an economic analysis of a designed plant of potato starch based bioplastic and to check for its economic

1.4                                                    PURPOSE OF THE STUDY

The purpose of the project is to study the potential of producing starch-based bioplastics using potato peels.

1.5                                                       SCOPE OF THE STUDY

The methodology of the project started with the preparation of the potato which included weighing, washing, peeling, dicing. It was followed by blending, slurring and filtration so as to extract maximum starch. The second step was the production of the bioplastic where water and glycerol was added to the starch with the presence of heat. Some mechanical and physical tests were done on some bioplastic samples and it was found that the bioplastic could withstand a load of 1 Kg with an elongation of 105 mm at break and 62 mm at peak, strain of 76% at break and 46% at peak, a stress of 0.063 N/mm2 at break and 0.207 N/mm2 and finally a young’s modulus of 3.467 N/mm2. From the investigation, 25% of starch was extracted from local potatoes with a bulk density of 1450 kg/m3. It was thus concluded that bioplastics from potato starch was a feasible solution as a substitute for petroleum based plastics.

1.6                                                         PROJECT ORGANISATION

The work is organized as follows: chapter one discuses the introductory part of the work, chapter two presents the literature review of the study, chapter three describes the methods applied, chapter four discusses the results of the work, chapter five summarizes the research outcomes and the recommendations.