The replacement of polyols synthesized from petrochemical by polyols originating from natural products, notably from vegetable oils and animal fats, has been the subject of research projects for a number of decades.
Very recently, however, the polymers industry has intensified its efforts to include the "green products", such as biobased polyols, in applications already available in the market. Examples of such applications include polyurethane foams, elastomers and epoxides.
This book describes the extraction of the natural constituents of several fruits and plants as well as their chemical conversion to polyols. In addition to the chemistry involved in the process, particular emphasis is attributed to their applications.
Table of Contents
Preface xi
1 Vegetable Oils, Animal Fats, Carbohydrates and Polyols 1
1.1 Introduction 1
1.2 Sustainability 3
1.3 Polyols from Vegetable Oils 5
1.3.1 Polyols from Triglycerides 5
1.3.2 Polyols from Glycerol 10
1.4 Polyols from Carbohydrates 12
1.4.1 Ligno-Cellulosics 12
1.4.2 Cellulose 12
1.4.2.1 Hydrolysis 13
1.4.2.2 Oxidative Degradation 13
1.4.2.3 Thermal Degradation 14
1.4.3 Hemicellulose 14
1.4.4 Lignin 15
1.4.5 Sucrose 16
1.4.6 Starch 19
1.4.6.1 Glucose 19
1.4.6.2 Sorbitol 20
References 22
2 Polyurethanes, Polyesters and Epoxies 25
2.1 Introduction 25
2.2 Polyurethanes 25
2.2.1 Rigid Foams 25
2.2.1.1 Isocyanates 26
2.2.1.2 Polyols 26
2.2.2 Flexible Foams 27
2.2.2.1 Isocyanates 28
2.2.2.2 Polyols 28
2.2.3 Microcellular Elastomers 28
2.2.3.1 Footwear 29
2.2.3.2 Integral Skin 31
2.2.4 Thermoplastic Polyurethane (TPU) Elastomers 32
2.2.4.1 Isocyanates 33
2.2.4.2 Polyols/Diols (Chain Extenders) 34
2.2.5 Casting Systems 34
2.2.5.1 Isocyanates 36
2.2.5.2 Polyols 36
2.2.5.3 Crosslinkers 36
2.2.5.4 Examples 36
2.2.6 Coatings 37
2.2.6.1 Urethane Oils/Uralkyds 37
2.2.6.2 Moisture Curable Coatings 38
2.2.6.3 Blocked Isocyanates 39
2.2.6.4 Two-Component Coatings 39
2.3 Polyesters 40
2.3.1 Unsaturated Polyesters 40
2.3.1.1 Alkyds 40
2.3.1.2 Drying Oils 42
2.3.2 Thermoplastic Polyesters 43
2.3.3 Polyester Polyols 45
2.4 Epoxies 46
References 48
3 Vegetable Oils and Fats 51
3.1 Introduction 51
3.2 Sources, Components and Extraction of Vegetable Oils 52
3.2.1 Soybean Oil 52
3.2.1.1 Source 52
3.2.1.2 Components of Soya Bean 54
3.2.1.3 Triglyceride (Oil) Extraction 67
3.2.2 Palm Oil 73
3.2.2.1 Source 74
3.2.2.2 Components 76
3.2.2.3 Extraction 79
3.2.3 Corn Oil 85
3.2.3.1 Source 85
3.2.3.2 Corn Kernel Components 87
3.2.3.3 Processing of Corn Kernels 88
3.2.3.4 Corn Oil Extraction and Refining 92
3.2.4 Linseed Oil 93
3.2.4.1 Source 93
3.2.4.2 Components of Flaxseed 94
3.2.5 Castor Oil 94
3.2.5.1 Source 94
3.2.5.2 Oil Extraction 94
3.2.5.3 Castor Oil Components 100
3.2.6 Rapeseed Oil 100
3.2.6.1 Source 100
3.2.6.2 Oil Extraction 101
3.2.6.3 Components of Canola Seeds, Rapeseeds and Canola Oil 105
3.2.7 Sunflower Oil 107
3.2.7.1 Source 107
3.2.7.2 Processing 109
3.2.7.3 Components of Sunflower Oil 110
3.2.7.4 Producers of Sunflower Oil 110
3.2.8 Vernonia Oil 110
3.2.9 Cashew Nut and Nutshell Oil 113
3.3 Comparative Data 117
3.3.1 Typical Oil Extraction from 100 kg of Oil Seeds 117
3.3.2 Fatty Acid Components of Vegetable Oil Triglycerides 118
3.3.3 Global Production 118
3.4 Fats 120
3.4.1 Fish Oil 120
3.4.2 Animal Fat 123
3.4.2.1 Lard 123
3.4.2.2 Beef Tallow 124
3.4.3 Comparative Data 124
References 126
4 Chemistry of Triglycerides and Fatty Acids 133
4.1 Introduction 133
4.2 Reactions of Double Bonds 133
4.2.1 Epoxidation 133
4.2.1.1 Chemical Epoxidation 134
4.2.1.2 Enzymatic Epoxidation 139
4.2.2 C=C Bond Cleavage 140
4.2.2.1 Ozonolysis 140
4.2.2.2 Metal Catalysis 142
4.2.2.3 Microbial Oxidation 144
4.2.2.4 Acid-Catalyzed Oxidation 144
4.2.3 C=C Bond Metathesis 145
4.2.4 Polymerization Reactions of Vegetable Oils 148
4.2.4.1 Homopolymerization 149
4.2.4.2 Copolymerization 149
4.2.4.3 Oxypolymerization 153
4.2.5 Hydrogenation 155
4.2.6 Dihydroxylation 158
4.2.6.1 Anti-Dihydroxylation 158
4.2.6.2 Syn Dihydroxylation 159
4.2.7 Addition 160
4.2.7.1 Hydroxybromination 160
4.2.7.2 Addition of Acetone/Malonic Acid 161
4.3 Reactions of Ester Groups 162
4.3.1 Hydrolysis of Ester Groups 162
4.3.1.1 Chemical Hydrolysis 162
4.3.1.2 Enzymatic Hydrolysis 163
4.3.2 Alcoholysis/Glycerolysis 164
4.3.3 Transesterification 167
4.3.4 Aminolysis 168
4.4 Reactions of Hydroxyl Groups 170
4.4.1 Dehydration 170
4.4.2 Esterification 170
References 171
5 Polyols from Triglycerides 177
5.1 Introduction 177
5.2 Reactions of Epoxides 178
5.2.1 Hydrolysis of Oxirane Rings 179
5.2.1.1 With Inorganic Acids 179
5.2.1.2 With Organic Acids 180
5.2.2 Alcoholysis of Oxirane Rings 182
5.2.2.1 Clay Catalyzed 182
5.2.2.2 HBF4 Catalyzed 184
5.2.3 Esterification of Oxirane Rings 185
5.2.3.1 With Carboxylic Acids 185
5.2.3.2 Acid Anhydrides 188
5.2.3.3 Hydroxy Carboxylic Acids 188
5.2.4 Aminolysis 189
5.3 Reactions of Ozonides 191
5.3.1 Ozonolysis Followed by Hydrogenation 191
5.3.2 Polyols from the Transesterification of Ozonolysis Intermediates 193
5.3.2.1 Amidification of Esters 194
5.3.2.2 Interesterification with Glycerol 194
5.4 Hydroformylation 196
5.5 Examples of Synthetic Methods 199
5.5.1 Glycerol Propoxylates 199
5.5.2 Castor Oil Alkoxylates 199
5.5.3 Mixed Alkoxylates 200
5.5.4 Oxidation in the Presence of Organometallic Complexes 200
5.5.5 Use of Double-Metal Cyanide (DMC) Complex Catalysts 201
5.5.6 Polyols from Palm Oil 203
5.5.7 Polyols from Oleic Acid (or Canola Oil) 206
5.5.8 Polyols from Soybean Oil and Chicken Fat 207
5.5.9 Autocatalytic Polyols 208
5.5.9.1 From Diethanolamine and Epoxidized Soybean Oil 208
5.5.9.2 Mannich Polyols from Cardanol 210
References 213
6 Carbohydrate-Based Polyols 219
6.1 Introduction 219
6.2 Bio Ethylene Oxide 219
6.3 Bio Propylene Glycol 223
6.3.1 1,3-Propanediol 223
6.3.1.1 Fermentation 224
6.3.1.2 Hydrogenation 225
6.3.2 1,2-Propanediol 225
6.3.2.1 Hydrocracking 225
6.3.2.2 Fermentation 226
6.4 Bio-Butanediol 226
6.5 Sucrose 228
6.5.1 Introduction 228
6.5.1.1 Sucrose from Cane Sugar 229
6.5.1.2 Sucrose from Beets 230
6.5.2 Propoxylated Sucrose Initiated Polyols 231
6.5.3 Propoxylated/Ethoxylated Polyols with Mixed Initiators 232
6.5.3.1 Sucrose/Ethylene Diamine Initiators 233
6.5.3.2 Sucrose/Glycerol Initiators 233
6.5.4 Propoxylation of Glucose Obtained from Starch 234
6.6 Sorbitol 235
6.6.1 Synthesis 235
6.6.2 Synthesis of Polyols from the Alkoxylation of Sorbitol 236
6.6.3 Sorbitol Derivatives 237
6.7 Carbohydrates from Corn Fibers 239
6.7.1 Chemical Treatment 239
6.7.2 Biochemical Treatment 240
References 242
7 Biobased Polyols and Their Applications 247
7.1 Commercial Vegetable Oil Polyols 247
7.1.1 Producers 247
7.1.2 PU Applications 247
7.1.2.1 Rigid Foams 247
7.1.2.2 Flexible Foams 269
7.1.2.3 Viscoelastic Foams 275
7.1.2.4 Castings/Sealants 284
7.1.2.5 Carpet Backing 289
7.1.2.6 Elastomers and Coatings 295
7.1.3 Epoxies 302
7.1.4 Polyesters 306
7.1.4.1 Alkyd Resins 306
7.1.4.2 Thermoplastic Polyesters 309
7.1.5 Acrylate Coatings 311
7.1.5.1 Introduction 311
7.1.5.2 Examples 311
7.2 Commercial Carbohydrate-Derived Polyols 313
7.2.1 Producers 313
7.2.2 General Technical Considerations 314
References 315
Appendix 319
Index 327
