Cellulose Based Nanocomposites with Shape Memory Properties

MARCOVICH, NORMA E.; AUAD, MARÍA L.; RICHARDSON, TARA; ARANGUREN, MIRTA I.

San José de Costa Rica

Congreso; XII Simposio Latinoamericano de Polímeros, X Congreso Iberoamericano de Polímeros SLAP 2010; 2010

Shape memory polyurethanes (SMPU) are already well known for their distinct properties, such as easy processability, high resistance to organic solvents and solutions, long term stability against exposure to sunlight, consistent elastic properties and biocompatibility. These materials have also the ability of “remembering” their original shape after being deformed and of recovering their original shape almost completely as a response to an external stimulus [1]. However, the main disadvantage of using SMPUs is their relatively weak recovery force [2]. Therefore, the SMPUs are usually used in the cases where only free recovery or very low recovery force and mechanical strength are sought. In order to increase the mechanical properties of these materials, SMPU’s have been reinforced with carbon or glass fibers, or ceramic filler particles [2]. Following this direction, our group had previously investigated the addition of cellulose nanocrystals into a commercial segmented thermoplastic polyurethane that showed shape memory features. This is a new approach for enhancing the elastic modulus of the composite SPU using a low concentration of bio-based nanocrystals and still reaching large deformations.