Chemistry study guide:Practical Guide to Polyvinyl Chloride
S.G. Patrick
Practical Guide to Polyvinyl Chloride
Contents
1 Introduction
1.1 Background
1.2 History
1.3 Major Advantages and Limitations
1.3.1 Major Advantages
1.3.2 Limitations
1.4 Applications
1.5 Competitive Materials
1.6 Market Share and Consumption Trend
1.7 Industry Outline and Major Suppliers
1.8 Material Pricing
1.9 Safety, Health, and Environmental Issues
1.9.1 Phthalate Plasticisers
1.9.2 Heat Stabilisers
1.9.3 Bisphenol A/Alkylphenols
1.9.4 Epoxidised Soya Bean Oil (ESBO)
1.9.5 Green Product Procurement Policies/Eco-labelling
1.9.6 End-of-life Issues
1.9.7 Fire Performance ……………………………………………………………………………… 8
2 PVC Resins …………………………………………………………………………………………………………. 11
2.1 Raw Starting Materials ………………………………………………………………………………… 11
2.2 Vinyl Chloride Manufacture …………………………………………………………………………. 12
2.3 Polymerisation ……………………………………………………………………………………………. 12
2.3.1 Homopolymers ………………………………………………………………………………. 13
2.3.2 Copolymers and Terpolymers …………………………………………………………… 15
2.3.3 Chlorinated PVC (C-PVC) ……………………………………………………………….. 17
2.4 PVC Resin Characterisation …………………………………………………………………………. 17
2.4.1 Molecular Weight …………………………………………………………………………… 17
2.4.2 Particle Size …………………………………………………………………………………… 17
2.4.3 Bulk Powder Properties …………………………………………………………………… 18
2.4.4 Porosity ………………………………………………………………………………………… 18
2.5 Storage and Transportation ………………………………………………………………………….. 18
2.6 Role of Additives ………………………………………………………………………………………… 18
2.7 Identifi cation ……………………………………………………………………………………………… 19
Practical Guide to Polyvinyl Chloride
3 PVC Additives …………………………………………………………………………………………………….. 21
3.1 Heat Stabilisers [1] ……………………………………………………………………………………… 21
3.1.1 Solid Form …………………………………………………………………………………….. 22
3.1.2 Liquid Stabilisers ……………………………………………………………………………. 24
3.2 Plasticisers …………………………………………………………………………………………………. 27
3.2.1 PVC/Plasticiser Compatibility [3, 4] …………………………………………………. 27
3.2.2 Plasticisation Process ………………………………………………………………………. 28
3.2.3 Plasticiser Infl uence on Physical Properties …………………………………………. 29
3.2.4 Plasticiser Choice and Selection [13] ………………………………………………….. 30
3.2.5 Plasticiser Types ……………………………………………………………………………… 32
3.3 Impact Modifi ers ………………………………………………………………………………………… 40
3.4 Process Aids ……………………………………………………………………………………………….. 42
3.5 Lubricants …………………………………………………………………………………………………. 42
3.6 Fillers ………………………………………………………………………………………………………… 43
3.6.1 Calcium Carbonate …………………………………………………………………………. 44
3.6.2 Other Fillers ………………………………………………………………………………….. 44
3.7 Flame Retardants (FR) and Smoke Suppressants (SS) ……………………………………….. 44
3.8 Pigments ……………………………………………………………………………………………………. 45
3.8.1 Titanium Dioxide (TiO2) …………………………………………………………………. 45
3.8.2 Other Inorganic Pigments ………………………………………………………………… 46
3.8.3 Organic Pigments …………………………………………………………………………… 47
3.8.4 Pigment Concentrates and Masterbatches …………………………………………… 47
3.9 Microbiocides …………………………………………………………………………………………….. 47
3.10 Blowing Agents …………………………………………………………………………………………… 48
3.11 Antioxidants and Light Stabilisers …………………………………………………………………. 49
3.12 Other PVC-P Additives ………………………………………………………………………………… 49
3.12.1 Antistatic Agents ……………………………………………………………………………. 49
3.12.2 Viscosity and Rheology Modifi ers ……………………………………………………… 49
3.12.3 Bonding Agents/Adhesion Promoters …………………………………………………. 50
4 Testing and Properties …………………………………………………………………………………………… 53
4.1 Density ……………………………………………………………………………………………………… 53
4.2 Water Absorption ……………………………………………………………………………………….. 53
4.3 Mechanical Properties …………………………………………………………………………………. 53
4.3.1 Hardness ………………………………………………………………………………………. 54
4.3.2 Tensile Properties ……………………………………………………………………………. 55
4.3.3 Flexural Properties ………………………………………………………………………….. 56
4.3.4 Impact Properties ……………………………………………………………………………. 57
4.3.5 Fatigue ………………………………………………………………………………………….. 58
4.4 Thermal Properties ……………………………………………………………………………………… 59
4.4.1 Thermal Conductivity ……………………………………………………………………… 59
4.4.2 Heat Defl ection Temperature ……………………………………………………………. 59
4.4.3 Vicat Softening Point ………………………………………………………………………. 60
4.4.4 Linear Expansion Coeffi cient ……………………………………………………………. 60
4.4.5 Specifi c Heat Capacity …………………………………………………………………….. 60
4.4.6 Cold Flex Temperature ……………………………………………………………………. 60
4.5 Electrical Properties …………………………………………………………………………………….. 60
4.5.1 Volume Resistivity ………………………………………………………………………….. 61
4.5.2 Dielectric Constant or Relative Permittivity ………………………………………… 61
4.5.3 Loss Modulus or Dissipation Factor ………………………………………………….. 62
4.5.4 Breakdown Voltage or Dielectric Strength ………………………………………….. 62
4.5.5 Arc Resistance ……………………………………………………………………………….. 62
4.6 Fire Properties ……………………………………………………………………………………………. 62
4.6.1 Self-ignition Temperature …………………………………………………………………. 62
4.6.2 Flame Ignition Temperature ……………………………………………………………… 63
4.6.3 Limiting Oxygen Index (LOI) …………………………………………………………… 63
4.6.4 NBS Cone Calorimeter ……………………………………………………………………. 63
4.6.5 Smoke Evolution ……………………………………………………………………………. 64
4.6.6 Fire Performance of PVC …………………………………………………………………. 64
4.6.7 Fire Testing in the EU ……………………………………………………………………… 65
4.7 Optical Properties ……………………………………………………………………………………….. 67
4.7.1 Transparency …………………………………………………………………………………. 67
4.7.2 Gloss Level ……………………………………………………………………………………. 68
4.7.3 Colour ………………………………………………………………………………………….. 68
4.8 Surface Properties ……………………………………………………………………………………….. 68
4.8.1 Abrasion Resistance ………………………………………………………………………… 68
4.8.2 Surface Resistivity …………………………………………………………………………… 69
4.9 Biological Behaviour ……………………………………………………………………………………. 69
4.9.1 Assessment under Food and Water Legislation ……………………………………. 69
4.9.2 Assessment under Medical Legislation ……………………………………………….. 72
4.9.3 Sterilisation ……………………………………………………………………………………. 74
4.10 Resistance to Micro-organisms ……………………………………………………………………… 76
4.11 Performance in Service …………………………………………………………………………………. 76
4.11.1 Maximum Continuous Use Temperature ……………………………………………. 76
4.11.2 Stability to Light, UV Radiation, and Weathering ………………………………… 76
4.11.3 Chemical Resistance ……………………………………………………………………….. 77
4.11.4 Permeability …………………………………………………………………………………… 78
5 Design ………………………………………………………………………………………………………………… 83
5.1 Design Considerations for PVC-U Materials ……………………………………………………. 83
5.1.1 Pipe ……………………………………………………………………………………………… 83
5.1.2 Exterior Construction Applications …………………………………………………… 85
5.1.3 Interior Construction Applications ……………………………………………………. 89
5.2 Design Considerations for PVC-P Materials ……………………………………………………. 89
5.2.1 Electrical Cable ………………………………………………………………………………. 89
5.2.2 Resilient Flooring …………………………………………………………………………… 90
5.2.3 Wall Covering ………………………………………………………………………………… 91
5.2.4 Roofi ng Membranes ……………………………………………………………………….. 92
5.2.5 Coated Metal …………………………………………………………………………………. 93
Practical Guide to Polyvinyl Chloride
5.2.6 Toys and Baby Care Items ……………………………………………………………….. 93
5.2.7 Safety and Personal Protection ………………………………………………………….. 93
5.2.8 Automotive and Transport ……………………………………………………………….. 94
5.2.9 Advertising Banners ………………………………………………………………………… 95
6 Processing of PVC ………………………………………………………………………………………………… 97
6.1 Dry Blend Mixing ……………………………………………………………………………………….. 97
6.1.1 High Intensity ………………………………………………………………………………… 97
6.1.2 Low Intensity …………………………………………………………………………………. 98
6.2 Liquid PVC Blending …………………………………………………………………………………… 98
6.3 Gelation …………………………………………………………………………………………………….. 99
6.4 Melt Processing ………………………………………………………………………………………… 100
6.4.1 Melt Compounding ………………………………………………………………………. 100
6.4.2 Extrusion …………………………………………………………………………………….. 101
6.5 Injection Moulding ……………………………………………………………………………………. 104
6.6 Extrusion Blow Moulding ………………………………………………………………………….. 105
6.7 Calendering ……………………………………………………………………………………………… 105
6.8 Plastisol Moulding Processes ………………………………………………………………………. 106
6.8.1 Rheology …………………………………………………………………………………….. 106
6.8.2 Spreading or Coating …………………………………………………………………….. 106
6.8.3 Rotational, Slush, and Dip Moulding ………………………………………………. 107
6.9 Powder Moulding Processes ……………………………………………………………………….. 107
6.9.1 Fluidised Bed ……………………………………………………………………………….. 107
7 Property Enhancement of PVC …………………………………………………………………………….. 109
7.1 Crosslinked PVC ………………………………………………………………………………………. 109
7.1.1 Chemical Crosslinking …………………………………………………………………… 109
7.1.2 Irradiation Crosslinking …………………………………………………………………. 110
7.2 Orientation ………………………………………………………………………………………………. 110
7.2.1 Pipe ……………………………………………………………………………………………. 110
7.2.2 Sheet …………………………………………………………………………………………… 111
7.3 Blends and Alloys ……………………………………………………………………………………… 111
7.3.1 Flexibilisers/Internal Plasticisers ………………………………………………………. 111
7.3.2 Ultrahigh Molecular Weight (UHMW) PVC ……………………………………… 112
7.4 Nanocomposites ……………………………………………………………………………………….. 113
7.4.1 Melt Intercalation …………………………………………………………………………. 113
7.4.2 Solvent Method ……………………………………………………………………………. 114
7.4.3 In Situ Polymerisation …………………………………………………………………… 114
7.5 Wood Composites …………………………………………………………………………………….. 114
8 Post-processing and Assembly ………………………………………………………………………………. 117
8.1 Post-processing …………………………………………………………………………………………. 117
8.1.1 Thermoforming ……………………………………………………………………………. 117
8.1.2 Printing and Coating …………………………………………………………………….. 117
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Contents
8.2 Assembly Techniques …………………………………………………………………………………. 119
8.2.1 Welding ………………………………………………………………………………………. 119
8.2.2 Adhesion …………………………………………………………………………………….. 121
8.3 Mechanical Assembly ………………………………………………………………………………… 122
8.3.1 Machining, Cutting, and Fastening ………………………………………………….. 122
9 Sustainable Development …………………………………………………………………………………….. 123
9.1 Environmental Attack and Response ……………………………………………………………. 123
9.2 Vinyl 2010/Chlorine Industry Sustainability Commitments ……………………………… 125
9.2.1 Chlorine Generation ……………………………………………………………………… 126
9.2.2 PVC Production Industry Charters ………………………………………………….. 126
9.2.3 Conversion with Additives ……………………………………………………………… 128
9.3 End of Life and Waste Management …………………………………………………………….. 132
9.3.1 PVC-rich Waste: Mechanical Recycling ……………………………………………. 133
9.3.2 PVC Feedstock Recycling ………………………………………………………………. 138
9.3.3 Incineration/Energy Recovery …………………………………………………………. 139
9.3.4 Controlled Landfi ll ……………………………………………………………………….. 140
9.4 Life Cycle Assessments ………………………………………………………………………………. 140
9.4.1 Eco-profi les ………………………………………………………………………………….. 141
9.5 Social Factors …………………………………………………………………………………………… 142
10 Causes of Failure ……………………………………………………………………………………………….. 145
Abbreviations and Acronyms ………………………………………………………………………………………. 147
Index ……………………………………………………………………………………………………………………….. 153
