Fate of hydrogen upon oxidation of zirconium alloys by water: Mechanistic insights from first principles calculations

Polyvinyl chloride (PVC) is one of the world’s most widely produced polymers and it is used in a wide range of areas such as building, transport, packaging, electrical/electronic and healthcare. Manufacturing of PVC products is dependent on several additives, e.g. plasticizers, heat stabilizers and flame retardants. To reduce the migration of additives in PVC products the incorporation of a nanofiller, mostly Montmorillonite (MMT) clay with high aspect ratio and large surface area, can be used to create physical barriers. There are also many results from literature showing that nanoclays have flame retarding qualities. Before MMT can be processed into a polymer matrix it has to be organically modified (OMMT), due to processability and compatibility issues. In many studies it has been shown that commercially available OMMTs are not suitable for PVC, hence they contribute to degradation processes [1]. In this paper the aim is to organically modify MMT for use in PVC. In an earlier project [2] the idea of chelating agents as organic modifiers was presented and here we combine theoretical studies using Hansen Solubility Parameters (HSP) with practical laboratory work to find out which parameters will have an influence on the final results. Various types of natural Montmorillonite clay were swelled in solvents with solubility parameters differing from each other. The clays were then treated with a proper organic modifier to increase interlayer spacing and improve compatibility with the polymer matrix. Thermogravimetric analysis (TGA), xray diffraction analysis (XRD) and scanning electron microscopy (SEM) were used to evaluate the outcome of the experiments. REFERENCES 1. Gong, F., et al., Thermal properties of poly(vinyl chloride)/montmorillonite nanocomposites. Polymer Degradation and Stability, 2004. 84(2): p. 289-294. 2. Yarahmadi, N., I. Jakubowicz, and T. Hjertberg, Development of poly(vinyl chloride)/montmorillonite nanocomposites using chelating agents. Polymer Degradation and Stability, 2010. 95(2): p. 132-137. O4 At the interface between life science and material science: atom probe tomography of osseointegration Gustav Sundell, TF In the field of biomedical technology a critical aspect is the ability to control and understand the integration of an implant device in living tissue. Despite the technical advances in the development of biomaterials, the elaborate interplay encompassing material science and biology on the atomic level is not very well understood. Within implantology, anchoring a biomaterial device into bone tissue is termed osseointegration. Due to the complex nature of the biological response that occurs at the interface, a detailed description of osseointegration on the smaller length-scales is still lacking. Herein it is