Heated tip-AFM of nanocomposite Polymer Membranes

Anasys Instruments Corp

Nanocomposite Polymer Membranes: Unlike traditional composite materials whose properties are influenced largely by the constituent components, nanocomposites exhibit such large specific surface areas that interfacial properties can significantly affect bulk behaviour. Poly trimethyl silyl propyne (PTMSP) has garnered attention since its discovery due to its very high permeability, high Tg and exhibited reverse selectivity[1, 2]. However, it was the discovery that the permeability and reverse selectivity could be significantly enhanced by the addition of silica nanoparticles that has generated most recent interest in the material[3-7]. This enhancement was particularly significant because it contradicted the Maxwell equation which predicts a reduction in permeability with the addition of an impermeable phase. Further studies on filler size and surface chemistry suggested that the addition of silica resulted in an increased fractional free volume in the polymer[8]. While the importance of the nanoscale PTMSP-Silica interface has been acknowledged, most of the data currently published is based on macroscopic and microscopic measurements and little is known about the local nanoscale properties of the material. Complex organic systems such as these are particularly well suited for bottom-up, molecular design approaches. In solid state form, these systems are known to exhibit bulk deviating material and transport properties due to finite size limitations and interfacial constraints. Practical examples are found in photonics, light emitting diode materials, nanoelectromechanical systems (NEMS), and organic and inorganic hybrid systems, such as nanocomposites.

Click here to view application note (PDF)