| ABSTRACT |
Shape memory foam is produced from emulsion polymerization. This is an aqueous process, green and environmentally friendly. The foaming process and porous formation occur by exploiting not only the use of blowing agent but also the use of water as pore template. The foam is stabilized via the three dimension crosslink of epoxy and hardener. These features register the method as a pioneer aqueous process to produce shape memory foam. In this product, shape memory property implies the ability of gradual recovery to original shape from a deformed sample causing by an external mechanical load. It is different from a permanent deformation in plastic or an elastic recovering response. The shape recovery occurs in a period of time after releasing load. In this way, the shape memory property was originated from the foam structure. Foam cell interconnection and porous cell wall are the main contribution factors to the shape memory property. The aqueous process is the suitable method to form these morphology features for foam. Besides, the flexible matrix of the shape memory foam is obtained from the polyamide epoxy adduct, which is a product of the reversed ratio of polyamide¿epoxy ratio using an excess stoichiometric amount of polyamide hardener. In this system, the polymer network is formed with low crosslink density and long polymer chain between crosslink. Furthermore, these advances of polymer network could also allow the foaming process (decomposition of blow agent and expansion of the matrix) occur better in the mixture, and obtain homogeneous cell foams.
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