Shape memory behaviors in cylindrical shell PLA/TPU-cellulose nanofiber bio-nanocomposites: Analytical and experimental assessment

Experimental and analytical investigations were conducted to assess shape memory behavior of Polylactic acid-thermoplastic polyurethane/cellulose-nanofiber bio-nanocomposites. Shape memory polymers were manufactured for experimental evaluation in cylindrical shell form. Subsequently, analytical assessment of shape memory behavior of thin sheet samples was accomplished based on the isothermal thermomechanical tests. Besides, evaluation of the acquired inclusive responses was performed for the cylindrical shell shape memory polymers, utilizing variance analysis. The results were indicative of dominant effect of programming temperature on force recovery ratio. Additionally, it showed that a higher force recovery can be attained at the higher weight ratios of cellulose-nonofiber and thermoplastic polyurethane. The analytical examination of the compounds with and without cellulose nanofibers correlates with the experimental results so that adding cellulose nanofibers to the polymeric matrix imposed notable promotion of stress recovery (over 40%) with a slight reduction in strain recovery.