Mechanism-Based Assessment of Structural and Functional Behavior of Sustainable Cottonid (Werkstofftechnische Berichte │ Reports of Materials Science and Engineering)

Ronja Victoria Scholz assesses the performance of cellulose-based Cottonid for implementation as sustainable construction material. Quasi-static and fatigue tests are performed in varying hygrothermal test conditions using mechanical testing systems in combination with integrable climate chambers. To investigate humidity-driven actuation properties, customized specimen holders are designed. Accompanying microstructural in situ experiments in analytical devices enable a profound understanding of effective material-specific damage and failure mechanisms. The findings are transferred into strength-deformation diagrams as well as Woehler curves, which enable a comparative evaluation of several process-related and environmental influencing factors and can directly be used for dimensioning of Cottonid elements for structural applications. The interpretation of thermoelastic material reponse during loading is used as scientific value for lifetime prediction. Comprehensive investigations on industrial standard materials as well as structurally optimized Cottonid variants provide a scientific basis for categorizing material’s structural and functional performance towards common technical plastics and wood. Foreword Preface Abstract Kurzfassung Contents Abbreviations Symbols Latin symbols Greek symbols List of Figures List of Tables 1 Introduction and Objective 2 State of the Art 2.1 Sustainability in Technical Applications 2.1.1 General Aspects 2.1.2 Resource Efficiency in Building and Automotive Industry 2.2 Technical Biopolymers and Biocomposites 2.2.1 Classification 2.2.2 Wood and Plant Fibers 2.2.3 Cellulose 2.3 Application Potential of Technical Biopolymers 2.3.1 Sustainable Construction 2.3.2 Bio-inspired Stimuli-responsive Polymers 2.3.3 Mechanisms of Hydration-induced Movement 2.4 Polymer Characterization 2.4.1 Chemical Composition and Microstructure 2.4.2 Mechanical Properties 2.4.3 Functional Properties 3 Cottonid 3.1 History and Manufacturing Process 3.2 Parameters for Structural Optimization 3.2.1 Raw Paper 3.2.2 Catalyst Bath 3.2.3 Post-treatment 3.3 Specimen Preparation 3.3.1 Mechanical Properties 3.3.2 Functional Properties 4 Investigation Methodology 4.1 Chemical Composition and Microstructure 4.1.1 Fourier Transform Infrared Spectroscopy 4.1.2 Light Microscopy 4.1.3 Scanning Electron Microscopy 4.1.4 Three-dimensional Laser Scanning Microscopy 4.1.5 Computed Tomography 4.2 Mechanical Properties 4.2.1 Quasi-static Deformation Behavior 4.2.2 In Situ Characterization Techniques 4.2.3 Fatigue Behavior 4.3 Functional Properties 4.3.1 Moisture Content and Photodegradation Behavior 4.3.2 One-dimensional Humidity-driven Deformation Behavior 4.3.3 Two-dimensional Humidity-driven Deformation Behavior 5 Results and Discussion 5.1 Chemical Composition and Microstructure 5.2 Mechanical Properties 5.2.1 Quasi-static Deformation Behavior 5.2.2 In situ Characterization 5.2.3 Fatigue behavior 5.3 Functional Properties 5.3.1 Moisture Content and Photodegradation Behavior 5.3.2 One-dimensional Deformation Behavior 5.3.3 Two-dimensional Deformation Behavior 5.4 Mechanism-based Correlation of Structural and Functional Behavior 6 Summary and Outlook Student works Publications Curriculum Vitae Published volumes References