Sheet Processing of Nano-clay Reinforced Poly Lactic Acid (PLA)/Poly Caprolactone (PCL)/Thermoplastic Polyurethane (TPU) Shape Memory Nanocomposites

Research on shape memory polymers (SMPs) are increasingly developed to understand their properties and governing mechanisms leading to their applications from medical products such as heart stents used in coronary artery, soft robotic, synthetic absorbable or permanent surgical stature to other applications such as those in automotive and toys industries. However, reported research so far has dealt with common melt mixing processes including hot press or extrusion injection molding techniques in fabrication thermoplastic based SMPs. In the current work, we for the first time introduce the calendering processing of three-phase blends of poly lactic acid (PLA)/poly caprolactone (PCL)/thermoplastic polyurethane (TPU) reinforced with nano-clay to examine the effect of addition of filler to the mechanical and shape memory performance of the parts. To achieve this, specific weight fractions of polymers were used followed by two-roller mixing of the blend utilizing a calendering machine for fabrication of polymer sheets. High shear forces together with intense thermal exposure were hypothesized toward fabrication of homogenous and thin sheets of specimens to obtain homogenous and uniform thickness of the thin films. Tensile behavior, thermal response and shape memory performance such as transition temperature and blocked force release of the parts were characterized and compared.

Sheet Processing of Nano-clay Reinforced Poly Lactic Acid (PLA)/Poly Caprolactone (PCL)/Thermoplastic Polyurethane (TPU) Shape Memory Nanocomposites Keywords:

Shape memory polymer (SMP) , calendering , nanoclay , composite sheet , blocked force