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Figure 3.1 - Molecular structure of PDMS [47].
3.1. Introduction to Poly(dimethylsiloxane)
PDMS is an optically-clear silicone elastomer with a molecular structure as
shown in Figure 3.1. The silicon-rich backbone results in very flexible polymer
chains which can easily slip past each other. The loose entanglement of these chains
provides PDMS with very prominent viscoelastic features, properties which can be
tuned by the molecular weight of the polymer chains. It is a chemically stable and
biocompatible polymer [48] with a poisson ratio of ,5, and is commonly used in
many diverse applications ranging from silicone caulks and lubricants to cosmetics