Biodegradable Polymers in the Circular Plastics Economy

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Half Title
Biodegradable Polymers in the Circular Plastics Economy
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Contents
Preface
1. Biodegradable Polymers – A Tutorial for a Circular Plastics Economy
1.1 Context
1.2 Plastics in the Environment – Biodegradation and Impact of Litter
1.3 Biodegradable Polymers
1.3.1 Polyesters
1.3.2 Polysaccharides
1.3.3 Lignin
1.3.4 Vitrimers – Recyclable Thermosets
1.4 Beyond Biodegradation
1.4.1 Recycling and End‐of‐Life
1.4.2 LCA
1.4.3 Implementing the “New Plastics Economy”
1.5 Conclusions and Outlook
References
2. Fundamentals of Polymer Biodegradation Mechanisms
2.1 Introduction
2.2 Overall Scheme of Polymer Degradation
2.3 Biodegradation of Polysaccharides
2.3.1 Cellulose
2.3.2 Starch
2.4 Biodegradation of Polyamides
2.5 Biodegradation of Polyesters
2.5.1 Polylactic Acid
2.5.2 Poly(ϵ‐caprolactone)
2.5.3 Polyhydroxyalkanoates
2.5.4 Polyethylene Terephthalate
2.6 Biodegradation of Hydrocarbons
2.6.1 Polyethylene
2.6.2 Polypropylene
2.6.3 Polystyrene
2.7 Biodegradation of Halogenated Polymers
2.7.1 Polyvinyl Chloride
2.7.2 Polytetrafluoroethylene
2.8 Biodegradation of Polyethers
2.8.1 Polyethylene Glycol
2.8.2 Polyurethane
2.9 Application of Biodegradation
2.10 Current Challenges and Future Prospects for Biodegradation of Plastics Wastes
References
3. Plastic Pollution. The Role of (Bio)Degradable Plastics and Other Solutions
3.1 Introduction and Problem Definition
3.2 Sources of Macroplastics and MNPs
3.2.1 Mismanagement of Waste
3.2.2 Accidental Release
3.2.3 MNPs in Products
3.2.4 Degradation of Outdoor Objects
3.2.5 Wear (Tires, Clothing)
3.2.6 Waste and Wastewater Management (Water/Wind)
3.3 Impacts of Macroplastics and MNPs
3.3.1 Ecological Impact of Macroplastics (Entanglement and Ingestion)
3.3.2 Economic Impact of Macroplastics
3.3.3 Ecological Impacts of MNPs
3.3.3.1 Aquatic Environment
3.3.3.2 Terrestrial Environment
3.3.3.3 Atmosphere
3.3.4 Threat to Human Health
3.3.4.1 MNPs in the Human Food Chain
3.3.4.2 Plastic‐Related Contaminants
3.3.4.3 Other Contaminants
3.3.5 Socio‐Economic Impacts of MNPs
3.4 Plastic Biodegradability
3.5 Solutions
3.5.1 Cleaning Up
3.5.2 Waste Mitigation
3.5.3 Material Design
3.5.4 Bringing It All Together
3.5.5 Policies and Legislation
3.6 Conclusions
References
4. Tutorial on Polymers – Manufacture, Properties, and Applications
4.1 Introduction
4.1.1 Today's Petrochemical Industry
4.1.2 Today's Bio‐based Plastic Industry
4.1.3 Environmental and Climate Challenges
4.2 Production of Polymers
4.2.1 Addition Polymers
4.2.2 Condensation Polymers
4.2.3 Thermosets
4.2.4 Renewable Monomers
4.2.4.1 Oils‐Based Monomers
4.2.4.2 Sugar‐Based Monomers
4.2.4.3 Lignocellulose‐Based Monomers
4.2.4.4 CO2‐Based Monomers
4.3 Main Polymers Applications
4.3.1 Rigids
4.3.2 Films
4.3.3 Fibers
4.3.4 Foams
4.3.5 CASE (Coatings, Adhesives, Sealants, Elastomers)
4.3.6 Composites
4.4 End‐of‐Life and Biodegradation
4.4.1 Reuse and Recycling
4.4.2 Biodegradation
4.5 Conclusions
References
5. Condensation Polyesters
5.1 Introduction
5.2 Preparative Methods
5.3 Biodegradation of Polyesters
5.3.1 Hydrolytic Degradation
5.3.2 Enzymatic Degradation
5.4 Aliphatic Polyesters
5.4.1 Poly(alkylene dicarboxylates)
5.4.2 Poly(hydroxy acids)
5.4.3 Cyclic Sugar‐Based Monomers
5.5 Semi‐aromatic Polyesters
5.5.1 Poly(butylene adipate terephthalate) (PBAT)
5.5.2 Furanoate Copolymers
5.6 Cross‐linked Polyesters
5.6.1 Multifunctional Alcohols or Carboxylic Acids
5.6.2 Incorporation of Functional Monomers
5.6.3 Cross‐linking of Native Polyesters
5.7 Applications for Biodegradable Condensation Polyesters
5.7.1 Biomedical Applications
5.7.2 Agricultural Applications
5.7.3 Packaging Material
5.8 Polyester Recycling
5.9 Concluding Remarks
References
6. Polyhydroxyalkanoates (PHAs) – Production, Properties, and Biodegradation
6.1 Introduction
6.1.1 General Aspects of Biodegradation of Polymers
6.1.2 General Aspects of Microbial Synthesis of PHAs
6.1.3 Types and Properties of PHAs
6.2 Biosynthesis – Substrates and Strains
6.2.1 Principle Stoichiometry of PHA Biosynthesis
6.2.2 Biosynthesis of scl‐ and mcl‐PHAs
6.2.3 Heterotrophic Feedstocks
6.2.4 Autotrophic Feedstocks
6.2.5 Syngas
6.2.6 Methane
6.2.7 Production Strains
6.3 Bioengineering: Bioreactor Design and Feeding Regime
6.3.1 Feeding Regime
6.3.2 Continuously Operated Bioreactors for Liquid Feed
6.3.3 Bioreactors for Gas Feed
6.3.4 Photo‐reactors for CO2 Feed
6.4 Downstream Processing for PHA Recovery
6.4.1 Classical Solvents
6.4.2 Halogen‐Free Solvents
6.4.3 Supercritical Solvents
6.4.4 Recovery by Chemical and Mechanical Disintegration of Biomass
6.4.5 Biological PHA Recovery
6.5 End‐of‐Life Options: Recycling and Biodegradation of PHAs
6.5.1 Recycling
6.5.2 Incineration
6.5.3 Mechanistic Considerations of PHA Degradation
6.6 Biodegradation – Added Value for Selected Applications
6.6.1 Packaging
6.6.2 Hygiene/Care/Cosmetics
6.6.3 Medical – Drug Delivery
6.6.4 Other Applications
6.7 Conclusions
References
7. Ring‐Opening Polymerization Strategies for Degradable Polyesters
7.1 Introduction
7.2 Ring‐Opening Polymerization Mechanisms
7.2.1 Cationic Ring‐Opening Polymerization
7.2.2 Anionic Ring‐Opening Polymerization
7.2.3 Coordination–Insertion Ring‐Opening Polymerization
7.2.4 Enzymatic Ring‐Opening Polymerization
7.3 ROP‐Based Polyesters
7.3.1 Lactones
7.3.2 Thermodynamics and Kinetics
7.3.3 Functionalization
7.3.3.1 ROP of Functional Lactones
7.3.3.2 Post‐polymerization Functionalization
7.3.3.3 Grafting
7.3.4 Four‐Membered Lactones
7.3.4.1 β‐Butyrolactone
7.3.4.2 Acid‐Substituted β‐Lactones (β‐Malolactonate)
7.3.4.3 Alkoxy‐Substituted β‐Lactones
7.3.4.4 Alkene‐Substituted β‐Lactones
7.3.5 Five‐Membered Lactones
7.3.5.1 γ‐Butyrolactone
7.3.5.2 α‐Angelicalactone
7.3.5.3 α‐Methylene‐γ‐Butyrolactone
7.3.5.4 Ether γ‐Lactones
7.3.6 Six‐Membered Lactones
7.3.6.1 δ‐Valerolactone
7.3.6.2 Unsaturated δ‐Lactones
7.3.6.3 Ester‐Substituted δ‐Lactones
7.3.6.4 Ether δ‐Lactones
7.3.6.5 Dilactones
7.3.7 Seven‐Membered Lactones
7.3.7.1 ϵ‐Caprolactone
7.3.7.2 Substituted and Functionalized ϵ‐Caprolactone
7.3.7.3 Ether‐ϵ‐Lactones
7.4 Relations Between ROP Polymers and Degradability
7.5 Conclusion
7.6 Outlook and Recommendations
References
8. Recent Developments in Biodegradable Cellulose‐Based Plastics
8.1 General Introduction
8.2 Cellulose
8.3 The Development of Cellulose Plastics
8.3.1 Cellulose Feedstock and Dissolving Pulp
8.3.2 Cellulose Derivatization
8.3.3 Cellulose Acetate and Cellulose Esters
8.3.4 Cellophane
8.3.5 Cellulose Fibers in Thermoplastic Formulations
8.4 Recent Developments in Thermoplastic Cellulose Derivatives
8.4.1 Characterization Methods for Lignocellulosic Biomass
8.4.2 Alternative Feedstocks for Dissolving Pulp and Production Routes
8.4.3 Ionic Liquids and Deep Eutectic Solvents for Cellulose Regeneration and Modification
8.4.4 New Derivatization Routes
8.4.5 Plasticizers
8.4.6 Mixed Cellulose Esters
8.4.7 Cellulose–Polymer Blends
8.4.8 (New) Properties and Processing Routes
8.4.9 New Applications
8.5 Biodegradation of Cellulose Derivatives
8.6 Conclusions
References
9. Ester Derivatives of Microbial Synthetic Polysaccharides
9.1 Introduction
9.1.1 Background of Bio‐Based Plastics
9.1.2 Polysaccharides
9.2 Zero Birefringence Property of Pullulan Esters
9.3 Bio‐Based Adhesives from Dextran (α‐1,6‐Glucan)
9.4 Films and Fibers from Paramylon and Curdlan (β‐1,3‐Glucan) Esters
9.5 Polymerization of α‐1,3‐Glucan and Films of α‐1,3‐Glucan Esters
9.6 High‐Performance Polysaccharide‐Branched Esters
9.6.1 Cellulose‐Branched Esters
9.6.2 β‐1,3‐Glucan (Curdlan) Branched Esters
9.6.3 α‐1,3‐Glucan‐Branched Esters
9.7 Enzymatic Esterification of Polysaccharides
9.7.1 Enzymes as Biocatalysts
9.7.2 Reaction Mechanism
9.7.3 Factors Influencing Enzyme Activity
9.7.4 Strategies for Efficient Biocatalyst Processes
9.7.5 Development Trend and Prospects
9.8 Biodegradation of Polysaccharide Ester
9.9 Summary
References
10. Biodegradable Lignin‐Based Plastics
10.1 Lignocellulose Biorefineries
10.2 Macromolecular Lignin Configuration
10.3 Industrial Availability of Lignins
10.4 Compelling Traits in Physicochemical Behavior of Kraft Lignin Species
10.5 Kraft Lignin‐Based Plastics
10.6 Tuning Strength and Production Cost of Plastics with High Kraft Lignin Contents
10.7 Ligninsulfonates (Lignosulfonates)
10.8 Laboratory Ball‐Milled Lignins
10.9 Blend Configuration in Ball‐Milled Lignin‐Based Plastics Exemplifies the General Case
10.10 Lignin–Lignin Blends
10.11 Biodegradation of Kraft Lignin‐Based Plastics
10.12 Alternative Formulations for Polymeric Materials Containing More than 50 wt% Lignin
10.13 Concluding Remarks
Acknowledgments
References
11. Design of Recyclable Thermosets
11.1 Introduction
11.1.1 Polymers and Plastics
11.1.2 Handling of Plastic Waste
11.1.3 Chemical Nature of Plastics
11.2 Design of Recyclable Thermosetting Polymers
11.2.1 Recyclability by Triggered Degradation
11.2.2 Dissociative Covalent Adaptive Networks
11.2.3 Vitrimers (Associative CANs)
11.3 Examples of Vitrimers
11.4 Adaptable Cross‐Linking of Conventional Polymers
11.5 Outlook and Summary
References
12. Managing Plastic Wastes
12.1 Introduction
12.2 Plastic Waste
12.3 Mechanical Recycling
12.4 Dissolution/Precipitation
12.5 Chemical Recycling
12.5.1 Depolymerization of Condensation Polymers
12.5.2 Melt Pyrolysis of Polyolefins
12.5.3 Alternative Pyrolysis Processes
12.6 Energy Recovery – Recycle Fuels and Incineration
12.7 Waste Destruction – Biodegradation
12.8 Life Cycle Analyses
12.9 Need for Fresh Carbon Input
12.10 Conclusion and Outlook
References
13. Life Cycle Assessment of Bio‐Based Plastics: Concepts, Findings, and Pitfalls
13.1 Introduction and Chapter Learning Objectives
13.2 “Bioplastics” Is a Confusing Term
13.3 LCA in a Nutshell
13.3.1 Concept and a Brief History
13.3.2 Procedure, Jargons, and Sciences Behind
13.3.2.1 Goal and Scope Definition
13.3.2.2 Life Cycle Inventory Analysis (LCI)
13.3.2.3 Life Cycle Impact Assessment (LCIA)
13.3.2.4 Interpretation
13.4 LCA Case Studies of Seven Single‐Use Plastic Items Made from Bio‐Based Resources: Highlights and Lessons Learned
13.4.1 Background, Aim, and Scope of the BIO‐SPRI Study
13.4.2 Key Findings
13.4.2.1 Biomass Feedstock Acquisition
13.4.2.2 Manufacturing Phase: From Biomass to Polymers, Materials, and End Products
13.4.2.3 Distribution to End User: Impacts from Transportation
13.4.2.4 End‐of‐Life (EoL) Post‐consumer Waste Management Scenarios
13.4.3 Comparisons with Petrochemical Plastics
13.5 Lessons Learned from the Case Studies and Looking Forward to a Circular Bio‐Based Economy
References
14. How to Create “A New Plastics Economy”? Marketing Strategies and Hurdles – Finding Application Niches
14.1 Introduction
14.2 Stories from the Past
14.2.1 Polyhydroxyalkanoates (PHAs)
14.2.2 Polylactic Acids (PLA)
14.2.3 Polyethylenefuranoates (PEF)
14.3 Greenwashing vs. Growing Pains
14.4 From Idea to Product: “Technical Readiness Levels”
14.4.1 Defining the Technical Readiness Levels
14.4.2 Application of the TRLs
14.4.3 Product(ion) Validation
14.5 Five Innovation Rules to Create “A New Plastics Economy”
14.5.1 Target Small‐Volume, High‐Value Applications to Open New Market Space
14.5.2 Time Right Instead of Fast
14.5.3 Go Local
14.5.4 Take Risks
14.5.5 Go “Green”
14.6 Conclusion
References
Index