774110 Biomaterial chemistry

Type
Lecture
Semester hours
2
Lecturer (assistant)
Liebner, Falk , Beaumont, Marco
Organisation
Offered in
Wintersemester 2024/25
Languages of instruction
Deutsch
Content

L 1: The different interpretations of the terminus "Biomaterial":
• Functional materials in direct interaction with biological systems
• Biomimetic materials
• Bio-inspired materials
• Bio-degradable materials
• Bio(polymer)-based materials

L 2: Important biopolymers, occurrence, isolation, structure, properties: Cellulose, Hemicellulose, Lignin, Starch, Cyclodextrin, Glycogen, Chitin, Chitosan, Pectin

L 3: Lignin: An important but challenging biopolymer: Biosynthesis, chemical structure, types of lignin, lignin isolation, functional groups

L 4: Lignin: An important but challenging biopolymer: Chemical modification of lignin using the great variety of functional groups and utilization of the respective lignin derivatives to create new lignin-based materials or to use them in composite materials with synthetic polymers
L 5: Lignin: An important but challenging biopolymer: Introduction of novel reactive sites as an approach to increase the reactivity of lignin. Introduction into the chemical analysis of lignins and discussion of established methods that allow the quantification of functional groups

L 6: Lignin: An important but challenging biopolymer: Degradation of lignin in soil and conversion to humic substances. Ammoxidation of lignin: A meaningful approach for the large-scale production of humus substitute materials to combat the globally increasing soil erosion and desertification.
L 7: Ageing and degradation of synthetic polymers
• chemical principles of thermal, chemical and irradiative polymer degradation
• measures to delay polymer degradation / measures to improve biodegradability

L 8: Processing of biopolymers
Technologies for the production of fibers, films, nano and microparticles, shaped parts
• Fibers: Spinning (wet, dry, electro spinning), spin-coating
• Films: Spin-coating / Langmuir-Blodget-Films / Layer-by-layer techniques; encapsulation of bioactive compounds for slow-release applications
• Nano- and microparticles: Jet-cutting, antisolvent precipitation, emulgation techniques
• shaped porous materials: Sol-Gel-processes, “Drying” of stable dispersions, supercritical drying

L 9: Supercritical CO2 techniques in polymer processing
• SAS: Supercritical Anti-solvent Processing
• scCO2 antisolvent precipitation
• scCO2 antisolvent drying
• RESS: Rapid expansion of supercritical solutions
• PGS: Particles from gas saturated solutions

L 10: Hydrogels
• General composition of hydrogels
• Principles of covalent and ionic cross-linking
• Characterisation of hydrogels
• Preparation of hydrogels from starch, hemicellulose and lignin

L 11: Aerogels
• Principal constitution, properties and applications
• Aerogels from plant and bacterial cellulose
• Preparation techniques, challenges, analytics
• Modification of cellulosic aerogels for selected applications

L12: Fibers
• Biopolymer-based fibers: state of research
• cellulosic fibers
o Direct solvents for cellulose
o Manufacturing of fibers through cellulose coagulation from solution state: The Lyocell process
o Manufacturing of fibers through cellulose derivatization and regeneration: The viscose process

L 13: Biomedical applications of biopolymer-based materials
• Slow release applications (fibers, films)
• Cell scaffolds for tissue engineering

L 14: Repetition, conclusions, outlook
Previous knowledge expected


Objective (expected results of study and acquired competences)

The character and content of this lecture succeeded to awaken the interest of the audience to follow joyfully recent achievements and actual developments in the field of „Chemistry of Biomaterials“. Based on selected scientific studies aiming at the development of hydrogels and aerogels for regenerative therapies, the students have been introduced to modern concepts of the development of „biomaterials“. Next to biomaterials in the strict sense – materials in direct contact with biological tissue – the participants of this lecture are now familiar with concepts targeting the development of biomimetic, bio-inspired, biodegradable, and bio-based materials and are qualified to work under guidance in respective projects.
By the example of lignin – one of the structurally most complicated natural polymers – and following a comprehensive repetition of the fundamentals of its biosynthesis, chemical structure and isolation from lignocellulosic source materials, the variety of opportunities for chemical modification of biopolymers and development of biopolymer-based functional materials have been discussed. Thereby the participants of this lecture have gained ready-to-use knowledge for chemical modification of other biopolymers provided respective guidance. In a similar way and exemplarily for lignin analytical methods capable of quantifying functional groups have been discussed.
This lecture imparts knowledge about the principles of polymer ageing and degradation, and the chemical background of the effects of primary and secondary antioxidants, and deactivators, respectively. Furthermore, the participants have been qualified for a better scientific understanding of current trends of the development of biodegradable polymers and can identify measures capable of retarding or fortifying the biodegradability of polymers.
Based on the discussion of selected aspects and opportunities concerning the processing of (modified) biopolymers (fibers, particles, gels, porous materials; use of supercritical carbon dioxide etc.), all participants have acquired comprehensive technological knowledge ready-to-apply for processing of similar materials.
You can find more details like the schedule or information about exams on the course-page in BOKUonline.