BINARY BLENDS OF POLYETHER-BASED POLYURETHANE BLOCK COPOLYMER AND POLY(VINYLIDENE FLUORIDE): PHYSICAL AND THERMAL PROPERTIES

Abstract

Miscibility and phase behavior studies of thermoplastic poly-ether-based polyurethane (TPEU) and poly(vinylidene fluoride) (PVF₂) blends were investigated by means of Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetry (TGA), and mechanical behavior. TPEU based on 1,6-diisocyanohexane (HDI), 1,4-bu-tanediol (BD), and 1000 molecular weight poly(tetramethylene oxide) (PTMO) was synthesized. It was shown by FTIR that the addition of PVF₂ to TPEU disrupted the intermolecular interactions between soft and hard segments in TPEU, and the interactions between an urethane carbonyl and protons of PVF₂ was stronger than that between urethane carbonyl and urethane NH. It was found that PVF₂ was immiscible with soft segment (PTMO) and miscible with hard segment and the degree of phase purity of the soft domain increased with increasing PVF₂ content. The presence of a specific intermolecular interaction between the hard segment and PVF₂ was suggested by an observed systematic depression in the melting point of the PVF₂ component. It was also found that the thermal stability, tensile strength, and Young's modulus increased proportionally to PVF₂.

Keywords:

• Thermoplastic Polyetherurethane
• Poly(Vinylidene Fluoride)
• Soft Segment
• Blending
• Melting Temperature
• Phase Separation
• Thermal Stability

ACKNOWLEDGMENTS

The authors are grateful to the Mu'tah University for its financial support.