Shape-memory materials classification

FIGURE 5.2.3 Classification of soft shape-memory materials from the viewpoint of nanoaivhitectonics. (a-c) Structures and (d) molecular mechanism, (a) Chemically cross-linked polymer network, (b) supramolecular network with clay nanosheets [29], and (c) inorganic/polymer composite network system, and their shape-memory profiles [30]. (d) The nanoscale molecular mechanism for one-way and two-way SME of a cross-linked semicrystalline polymer system. 

FIGURE 5.2.4 Classification of soft shape-memory materials fiom the viewpoint of macroarchitectonics (forms). 

Abstract This chapter describes vegetable oil-based polymer nanocomposites. It deals with the importance, comparison with conventional composites, classification, materials and methods, characterisation, properties and applications of vegetable oil-based polymer nanocomposites. The chapter also includes a short review of polymer nanocomposites of polyester, polyurethanes and epoxies based on different vegetable oils and nanomaterials. The chapter shows that the formation of suitable vegetable oil-based polymer nanocomposite can be considered to be a means of enhancing many of the desirable properties of such polymers or of obtaining materials with an intrinsically new set of properties which will extend their utility in a variety of advanced applications. Vegetable oil-based shape memory hyperbranched polyurethane nanocomposites can be sited as an exampie of such advanced products. 

There is a host of other applications for alloys displaying this effect—for example, eyeglass frames, tooth-straightening braces, collapsible antennas, greenhouse window openers, antiscald control valves on showers, women s foundation-garments, fire sprinkler valves, and biomedical applications (such as blood-clot filters, self-extending coronary stents, and bone anchors). Shape-memory alloys also fall into the classification of smart materials (Section 1.5) because they sense and respond to environmental (i.e., temperature) changes. 

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