Preparation And Properties Of Waterproof & Moisture Vapor Permeable Films Based On Blends Of Thermoplastic Polyurethane And Low Melt Point Polyester Used For Environmentally Friendly Lamination

Blends of Estane(?) thermoplastic polyurethane (TPU) and low melt polyester were prepared via melt blending and the blend films were prepared via blow molding. The morphology, thermal properties, and rheology of the blends, and the properties as moisture vapor permeable films were studied.Differential scanning calorimetry (DSC) and Fourier transformed infrared (FTIR) investigation indicated that the TPU was compatible with the low melt polyester. Scanning electron microscopy (SEM) micrographs exhibited a particle-dispersed type of the morphology, in which the low melt polyester was finely dispersed as regular spherical particles in the TPU matrix when the content of the aliphatic polyester was below 30 wt.%; however, the dispersed domain presented an irregular form due to the aggregation when the content of the aliphatic polyester reached 40 wt.%. Characterization of rheological behavior indicated that the process ability of TPU was increased after it was mixed with low melt polyester.