Degradation of polymers is both an incorporated quality of some materials and an important factor in the use of others. Understanding the degradation of polymers is key in multiple industries from toy manufacturing to coating. Knowledge of degradation may present new opportunities in the use of polymers. A large research project, Dreamwind, investigate how composites used in production of wind turbines become reusable. The goal is to disassemble and reassemble the composite-material in new products. Intentional degradation of polymers is also important in life science where timed degradation of polymers present new opportunities in drug-delivery and regenerative medicine.
Polymer Degradation by Kristoffer Almdal, DTU Nanotech
Different modes of chemical and physical degradation in polymers are described. Examples drawn from degradation studies of rubbers and thermoplastic will be given. The basis for degradation prediction based on accelerated testing and identification degradation pathways are described. Accelerated methods for studying degradation are described and the pitfalls are discussed. Finally, a presentation is given on the opportunities offered by miniaturization of test specimens combined with precise mechanical measurements and modelling.
Polymer Degradation in Coatings – Good or Bad? by Jens Ravnsbæk, Teknos
In paint and coatings products polymer degradation can play an important role. Often as an undesirable property with the potential to harm to the products ability to make the protected surface last longer. However, in at least one special product category, knowledge and deep insight in polymer degradation, especially thermal degradation, can serve as a useful tool in designing products. In this talk, I will give you a short introduction to the exciting world of fire retardant coatings and how polymer degradation can be a desirable property.
Degradation of Semicrystalline Polyesters and Links to End Product Performance by Emil Andersen, LEGO Systems A/S
Degradation of polymers is a widely complex system of interactions in finished products, and in academical work it can be difficult to cover all bases. Work has been done to evaluate physical ageing, a central degradation effect that causes embrittlement in amorphous and semicrystalline polymers. Physical ageing has been shown to affect mechanical properties and is easily evaluated by DSC and accelerated by temperature in Arrhenius behavior in PCTT. Future work in evaluation of ABS, MABS, PBT, PC, PCTT, PETG, PET-R and PET-R-IM in a real-life exposure and laboratory UV-sources will also be presented.
Understanding Polymer Rheology using Computer Simulations by Ramin Aghababaei, Department of Engineering, Aarhus University
Macroscopic behavior of polymeric materials emerges from a rich variety of microscopic phenomena involving mechanics and physics, chemistry and material science at disparate time and length scales. Recent advances in computer simulations opened up a new possibility to investigate otherwise hidden mechanisms of polymer degradation. In this talk, we present our recent progresses toward modeling mechanical and rheological behaviors of polymers, with application to injection molding and tribology. A coarse-grained numerical technique for studying the evolution of internal structure of polymeric network will be presented and its application will be discussed.
Epoxy Matrices Modified by Green Additives for Recyclable Materials by Mogens Hinge, Department of Engineering, Aarhus University
Epoxy-based thermosets are one of the most popular matrix materials in many industries due to its light-weight, high strength and anti-corrosive nature. Incorporation of a bio-based additive (L-cystine) within a commercial epoxy system leads to a cross-linked material that can be fractionated under mild and environmentally benign conditions . The material has been analyzed by FTIR and solid-state NMR to ensure incorporation and fully curing of the matrix. Further, modified epoxy matrices with only 5 mol% hardener equivalent substituted are demonstrated to have similar mechanical and thermal properties compared to the unmodified epoxy systems. Solvent resistance of the modified epoxy was tested and showed the same resistance towards the most common solvent as unmodified epoxy system. Thus, additive formulation and fractionation based on green chemistry principles have been demonstrated, and a recyclable epoxy matrix developed.
 M. L. Henriksen et al., ChemSusChem, 2017, 10 (14), 2936-2944.
The Danish Innovation Foundation (FI No: 5152-00003A) is gracefully thanked for the financial support.
On-demand Decomposition of Implantable Biomaterials by Alexander Zelikin, Department of Chemistry, Aarhus University
We aim to develop a technology that addresses a fundamental gap in biomedical engineering, namely the design of implantable biomaterials that fully disintegrate when remotely triggered by a non-invasive, non-harmful trigger. To achieve this, we investigate hydrogels as thermoreversible matrices. Key to the overall success was the identification of suitable thermoreversible chemistry that would afford stable biomaterials and be amenable to decomposition under non-harmful conditions. Second, equally important key was the engineering of stimuli response that would be generated locally, within the biomaterial. We anticipate that this technology would prove useful in biomedicine but also outside the realm of biomaterials in diverse applications, such in production of reversible adhesives, dissolvable commodity items, etc.