MS Word PDF Plain Text
Call or whatsapp: +2347063298784 or email: update@iprojectworks.com.



Effect of thermal treatment on physical and chemical properties on recycled polypropylene



ABSTRACT

Polypropylene is widely used today in industries and also at home and its production has increase drastically over the years making polypropylene products a major contributor in environmental waste. Therefore, instead of throwing away wasted or unusable polypropylene to where it may cause harm to the environment and the whole biodiversity, recycling comes to rescue. The objective of this study is to determine the change in properties of polypropylene with recycling.For this purpose, the mechanical properties of polypropylene using five recycling generation were determined.

The polypropylene materials were cut into flakes and pretreated before recycled mechanically at 180-2100C with fabricated mold.ASTM D638 type II specimen dimensions was chosen for tensile test. Ultimate tensile stress test relates the mechanical properties such as tensile strength, elastic modulus and percent elongation to failure to the recycling generations.

The curves which were generated prove that the polypropylene properties decrease with recycling. FTIR analysis affirmed that the chemical structures of the material were not affected by the recycling process.

However, the slight decrease in properties can be compensated by adding a virgin polypropylene at a ratio before recycling. Conservative safety factors and plastics additives, filler inclusion can also correct the decrement.

Recycling of plastic materials is effective in conserving the environment andenhancing the life cycle of these materials.

 

 

TABLE OF CONTENTS

TITLE PAGE.. i

LETTER OF TRANSMITTAL.. ii

CERTIFICATION.. iii

DEDICATION.. iv

ACKNOWLEDGEMENT. v

ABSTRACT. vi

TABLE OF CONTENTS. vii

LIST OF TABLES. x

LIST OF FIGURES. xi

LIST OF ABBREVIATIONS. xiii

 

CHAPTER ONE:       INTRODUCTION.. 1

1.1        Background……………………………………………………………………...1

1.2        Project objective…………………………………………………………………3

1.3 Justification. 4

 

CHAPTER TWO:     LITERATURE REVIEW... 5

2.1        Plastics. 5

2.2        Plastic recycling. 6

2.2.1         Polyethylene Terephthalate. …. 8

2.2.2         Polyethylenes. 10

2.2.3         Polyvinyl chloride. 13

2.2.4         Polystyrene. 14

2.3        Polypropylene. 15

2.3.1         History of polypropylene. 16

2.3.2         Molecular structure of polypropylene. 17

2.3.3         Properties of polypropylene. 19

2.3.4         Applications of polypropylene. 20

2.4        Physical and Chemical Testing. 22

2.4.1         Fourier Transform Infrared Spectroscopy (FTIR) 22

2.4.2         Ultimate Tensile Strength (Ultimate tensile stress (UTS)) 24

 

CHAPTER THREE:      METHODOLOGY.. 26

3.1        Material Selection. 26

3.1.2         Material pretreatment 26

3.2.2         Fabrication of Mold. 26

3.2        Experimental Procedure. 28

3.3        Testing. 33

3.3.1         Fourier Transform infrared spectroscopy. 33

3.3.2         Mechanical testing. 33

 

CHAPTER FOUR:      RESULTS AND DISCUSSION.. 36

4.1        FTIR Analysis. 36

4.2        Mechanical Properties. 44

4.1.1 Ultimate Tensile Strength. 45

4.1.2         Elasticity Modulus. 48

4.1.3         Elongation Percent 48

4.1.4         Tensile Stress and Strain. 53

 

CHAPTER FIVE:      CONCLUSION AND RECOMMENDATIONS. 59

5.1    Conclusion………………………………………………………………………59

5.2    Recommendation……………………….……………………………………….61

 

REFERENCES…………………………………………………………………………..62

APPENDICES…………………………………………………………………………..69

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

LIST OF TABLES

Table 2.1: Table of Resin Identification Codes for Different Plastics. 9

Table 2.2: The mechanical properties of polypropylene and its values. 21

Table 3.1: Calculated pressure summary table. 29

Table 4.1:  IR table of functional groups according to their range. 37

Table 4.2: Summarized Ultimate tensile stress (UTS) data for each generation. 46

Table 4.3:  Summarized Elasticity Modulus. 49

Table 4.4: Elongation Percent data for each recycled generation. 51

Table I: Results for 1st Generation……………………………………………………….73

Table II: Results for 2nd  Generation……………………………………………..............74

Table III: Results for 3rd  Generation…………………………………………………….75

Table IV: Results for 4th Generation…………………………………………………….76

Table V: Results for 5th Generation……………………………………………………..77

 

 

 

 

 

LIST OF FIGURES

Figure 2.1:  Schematic of the nature of chain branching varieties of polyethylene. 11

Figure 2.2: Structure of polypropylene monomer types. 18

Figure 3.1a: Waste Polypropylene materials gathered for the experiment 27

Figure 3.1b: Pre-treated polypropylene flakes. 27

Figure 3.2:  Experimental Set up. 30

Figure 3.3: First generation sample from first run. 31

Figure 3.4: Typical Dog bone shaped ASTM D638 specimen used for Tensile test 32

Figure 3.5: Typical Stress-Strain diagram.. 34

Figure 4.1: FTIR spectrum of 1stgeneration sample. 38

Figure 4.2: Reference IR polypropylene spectrum.. 39

Figure 4.3: IR spectrum of 2nd generation. 40

Figure 4.3: IR spectrum of 3rdgeneration. 41

Figure 4.3: IR spectrum of 4th generation. 42

Figure 4.4: FTIR spectrum of  5th generation. 43

Figure 4.5: Linear regression of Ultimate tensile stress (UTS) for all generations. 47

Figure 4.6: Elastic Modulus vs recycled generation trend. 50

Figure 4.7 Elongation percent vs recycling generation. 52

Figure 4.8: Tensile stress strain diagram for 1st recycling generations. 54

Figure 4.9: Tensile stress strain diagram for 2ndrecycling generations. 55

Figure 4.10: Tensile stress strain diagram for 3rdrecycling generations. 56

Figure 4.11: Tensile stress strain diagram for 4threcycling generations. 57

Figure 4.12: Tensile stress strain diagram for 5threcycling generations. 58

Figure  A: Comparison of the stress strain for all generation……………………………72

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

LIST OF ABBREVIATIONS

UTS                                         Ultimate Tensile Strength

UTM                                       Universal Testing Machine

ASTM                         American Society of Testing and Materials

PET, PETE                              Polyethylene terephthalate

PE                                           Polyethylene

PP                                            Polypropylene

LPDE                                      Low-density polyethylene

HDPE                                     High-density polyethylene

LLDPE                                   Linear low-density polyethylene

PVC                                        Polyvinyl chloride

PS                                            Polystyrene

ABS                                        Acrylonitrile- butadiene-styrene

SAN                                        Styrene-acrylonitrile 

 SMA                                      Styrene-maleic anhydride

BOPP            Biaxially oriented film

FTIR        Fourier Transform Infrared Spectroscopy

DTA       Differential Thermal Analysis

DSC     Differential Scanning Calorimetry

ATR        Attenuated Total Reflectance


CHAPTER ONE

INTRODUCTION

1.1       Background

During last decades, the great population increase worldwide together with the need of people to adopt improved conditions of living led to a dramatically increase of the consumption of polymers (mainly plastics). Materials appear interwoven with our consuming society where it would be hard to imagine a modern society today without plastics which have found a myriad of uses in fields as diverse as household appliances, packaging, construction, medicine, electronics, and automotive and aerospace components. A continued increase in the use of plastics has led to increase the amount of plastics ending up in the waste stream, which then becomes a threat to the environment when the wastes are not decomposable(Hamad et al., 2013). Environmental issues are becoming prioritized in most government and community development agendas. This has motivated the search for economically efficient and ecologically effective material and energy recycling technologies (Petts, 2000). For example, the development and use of strategic technologies driven by recycling credit scheme and the imposition of the landfill tax to preserve landfill void for the future disposal of untreatable residues in England(Read et al.,1998). The potential environmental impacts from plastics are categorized under global warming, acidification, eutrophication and photochemical ozone creation(Bos et al., 2007).

 

 

Polypropylene account for around 22% of the total production of plastics in 2008, making it the second largest plastic produced beside polyethylene which is 23.7% (Plastic waste Management Institute, 2009).Polypropylene plastics or also known as polypropene, are materials that are used worldwide since the 19th century (Scheirs, 1998). Polypropylene plastics are widely used in our daily life as kitchen utensils, in toy productions, as insulators for electrical devices, and also in industrial sites as safety equipment(Gaurina-Medijumurec, 2014).  Since polypropylene is widely used today in industries and also at home, its production has increase drastically over the years with increasing production of polypropylene made products. Therefore, polypropylene products is a major contributor to the pollution in the world today and now acting as a threat to both man and the whole biodiversity(Anthony, 2003). Itsnon-biodegradability makes post-consumer polypropylene a major environmental issue. Disposal of polypropylene waste by burning is not an environmentally friendly as the gases released are toxic.

Several options have been considered to reduce polypropylene waste such as reuse and recycling (Aurrekoetxeaet al., 2011). The most common examples of reuse are with glass containers, where milk and drinks bottles are returned to be cleaned and used again(Hamad et al., 2013). Reuse is not widely practiced in relation to plastic packaging of plastic products in general tend to be discarded after first use. However, there are examples of reuse in the marketplace. For example, a number of detergent manufacturers market refill sachets for bottled washing liquids and fabric softeners. Consumers can refill and hence reuse their plastic bottles at home, but in all of these cases the reusing of the plastic bottles and containers do not continue for long time especially in the food applications which makes recycling the best alternative.

Mechanical recycling and chemical recycling are the most widely practiced of these methods. However, from industrial point of view, the mechanical recycling is the most suitable because its low cost and reliability (Hamad et al., 2013). Mechanical recycling also known as physical recycling, the plastic is ground down and then reprocessed and compounded to produce a new component that may or may not be the same as its original use (Cui and Forssberg, 2003).

As to this, the recycling of post-consumer polypropylene polymer products is one of the factors in reducing the amount of wastes material produced every day (Harold, 2003). However, until today, the research on the mechanical properties of recycled polypropylene is not widely explored in open literature. Besides that, not much input of the properties of the recycled products either in mechanical or physical properties is comparable with the pure polypropylene materials. Thus, the study on the mechanical properties of the recycled polypropylene product is necessary.

 

1.2       Project objective

The main objective of this project are:

a) To design and fabricate a mold for purpose of this research

b) To determine how physical and chemical properties of polypropylene changes with recycling.



Delivery Assurance: This Project material is delivered within 15-30 Minutes. Click below to download complete material.


Download Complete Project Material

Search for more Project topics and Materials on this websites. There are numerous Project Topics, enter the topic and Click to Search.