Degradability of Polymers for Implantable Biomedical Devices

Many key components of implantable medical devices are made from polymeric materials. The functions of these materials include structural support, electrical insulation, protection of other materials from the environment of the body, and biocompatibility, as well as other things such as delivery of a therapeutic drug. In such roles, the stability and integrity of the polymer, over what can be a very long period of time, is very important. For most of these functions, stability over time is desired, but in other cases, the opposite–the degradation and disappearance of the polymer over time is required. In either case, it is important to understand both the chemistry that can lead to the degradation of polymers as well as the kinetics that controls these reactions. Hydrolysis and oxidation are the two classes of reactions that lead to the breaking down of polymers. Both are discussed in detail in the context of the environmental factors that impact the utility of various polymers for medical device applications. Understanding the chemistry and kinetics allows prediction of stability as well as explanations for observations such as porosity and the unexpected behavior of polymeric composite materials in some situations. In the last part, physical degradation such interfacial delamination in composites is discussed

Housing Metanoia: Accommodating the Modern Family’s Changing Spatial Needs Through Flexible Design

Thesis (Master's)--University of Washington, 2016-12The goal of this investigation is to understand how architecture can respond to the existing housing stock to accommodate a more family/ community-centered living opportunity through flexible spaces. The design will allow residents to incrementally expand or contract their living spaces through a modular approach thus: bring families back into urban neighborhoods through thoughtful multi-generational housing design, create a community of diverse ages, encourage a sustainable lifestyle, and address affordability in desirable urban neighborhoods