Search

Packaging application of the materials require strong barrier as well as mechanical properties. Majority of the reports in the literature have studied the mechanical properties while neglecting the barrier properties and it is generally assumed that the improvement in mechanical properties leads to automatic enhancement of barrier performance. However, it may not be true in all the cases as the permeation properties are more sensitive to interface between the polymer and filler phases. The incompatibility between the filler surface modification and polymer or the presence of excess surface modification on the filler surface can negatively impact the permeation properties, while the mechanical performance may still enhance. The current chapter focuses on the two very important elastomeric materials used in large amounts in packaging industry. Various factors affecting the barrier performance have been quantified. Use of not only montmorillonite, but also vermiculite has been presented. The importance of clean filler surface on the composite properties has also been underlined. The determination of average aspect ratio as a tool to control or tune the microstructure and properties of the nanocomposites has been shown with the help of finite element computer models. [ABSTRACT FROM AUTHOR]

The rapid progress in cell and developmental biology has clearly revealed that substrate elasticity and mechanical stimulation significantly affect cell function and tissue development. Further, many engineered soft-tissue constructs such as vascular grafts, cardiac patches, and cartilage are implanted in a mechanically dynamic environment, thus successful implants must sustain and recover from various deformations without mechanical irritations to surrounding tissues. Ideal scaffolds for these tissue engineering applications would be made of biodegradable elastomers with properties that resemble those of the extracellular matrix, providing a biomimetic mechanical environment and mechanical stimulation to cells and tissues. However, traditional biodegradable scaffold materials such as polylactide, polyglycolide, and poly(lactide-co-glycolide) are stiff and are subjected to plastic deformation and failure under cyclic strain. Consequently, for the past decade, many novel bioelastomers have been developed and extensively investigated for applications in tissue engineering. Both thermoplastic elastomers such as polyurethane, poly(ε-caprolactone) copolyester, poly(ether ester) and thermoset elastomers such as crosslinked polyesters have been developed and evaluated to engineer various tissues such as heart muscle and valves, blood vessels, skin, and cartilage. This chapter will cover representative bioelastomers and their applications in tissue engineering to highlight recent advances in this area. [ABSTRACT FROM AUTHOR]