Comparing of melt blending and solution mixing methods on the physical properties of thermoplastic polyurethane/organoclay nanocomposite films

Abstract

In this study, microstructural features and physical properties of thermoplastic polyurethane (TPU)/organoclay nanocomposites films prepared via melt blending (MB) and solution mixing (SM) methods were investigated in detail. Amount of organoclay into the composition varied in the range of 2 and 8 wt%. Microstructural properties of samples were characterized by X-ray diffraction, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) methods. It was found that the organoclay layers exhibited better dispersion, exfoliated, and semi-exfoliated structure in the MB samples than the SM counterparts. Viscoelastic properties of samples were also studied by measuring the rheological behaviors of bulk samples in an oscillatory rheometer in the melt state and measuring of the time-dependent nonlinear creep behaviors of film samples in a dynamic mechanical analyzer in the solid state. Gas and water vapor permeability (WVP) values of nanocomposite films were measured. Based on the melt rheology measurements, it was found that the MB samples showed characteristic solid-like behavior and higher improvement in storage modulus at low-frequency region. Creep behaviors of samples were also quantified with the four-element Burger model. It was found that the introducing of organoclay into the composition via MB method yielded more improvement in the creep resistance, gas, and WVP values of films than the SM counterparts, possibly due to the better dispersion of organoclay layers into the TPU structure. Based on the improvement in permeability and mechanical properties of the samples and also SEM and TEM observations, the average aspect ratio value ( Af) of organoclay stacks was estimated in the range of 15–20 for the MB samples.

A Review of the Synthesis and Applications of Polymer–Nanoclay Composites

“…The results showed that simple reactive melt blending may improve the tensile stress and dynamic modulus of SAN membranes and the dispersion of CNTs in SAN matrix. Ercan et al [88] compared the effects of melt blending and solution blending methods on the physical properties of thermoplastic polyurethane/nanoclay composite films; nanoclays exhibited a higher dispersion, exfoliated, and semi-exfoliated structures in the melting blending synthesized samples compared to those from the solution blending experiments. The melt blending method appeared to result in improvements in creep resistance, and the gas and water vapor permeability of polyurethane/nanoclay films.…”

Additive Manufacturing: A Novel Method for Developing an Acoustic Panel Made of Natural Fiber-Reinforced Composites with Enhanced Mechanical and Acoustical Properties

“…ere are also techniques which are used in compounding the reinforcement into the polymer matrix without the moldings. Out of all the available techniques, melt blending is one of the easier and environmental friendly techniques for producing polymer composites [137]. Ibrahim et al experimented with kenaf fibers as reinforcement in PLA as a polymer matrix by the melt blending technique [138].…”

Recyclable polyurethane/nanoclay films

“…Polyurethane (PU)/clay systems are one of the current organic/inorganic nanocomposites being extensively studied . The main goal of such studies is the preparation of materials with targeted functional properties.…”

“…The main goal of such studies is the preparation of materials with targeted functional properties. The presence of clay in a PU matrix can positively influence gas transport , mechanical , thermal , tear , and anticorrosion properties of nanocomposites. PU/clay composites can also be used as scratch‐resistant , flame‐retardant or shape‐memory materials .…”