Enhancing polyurethane properties via soft segment crystallization

• Published in: Polymer (Guilford) Vol. 46; no. 23; pp. 10158 - 10166
• Main Authors: Sonnenschein, Mark F., Lysenko, Zenon, Brune, Douglas A., Wendt, Benjamin L., Schrock, Alan K.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 14.11.2005; Elsevier
• Subjects: Applied sciences; Crystallization; Elastomer; Exact sciences and technology; Mechanical properties; Organic polymers; Physicochemistry of polymers; Polyurethane; Properties and characterization; Polyurethane; Elastomer; Crystallization; Elastic modulus; Polyurethune; Mechanical properties; Composition effect; Experimental study; Polyurethane elastomer; Compressive stress; Lamellar structure; Esterurethane polymer; Morphology; Supramolecular structure; Foam(plastics); Property structure relationship; Tear strength; Etherurethane polymer; Mechanical hysteresis
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/j.polymer.2005.08.006

Semi-crystalline polyester diols with relatively high melting points and enthalpies of crystallization are shown to form nearly co-continuous lamellar structures in thermoplastic polyurethanes using polyether soft segments. This high aspect ratio crystalline structure results in materials with exceptional tensile and elastic properties compared to materials made with conventional semi-crystalline soft segments such as polycaprolactone or polybutylene adipate. Additions of semi-crystalline soft segment to foam formulations also result in increased hardness measured by standard foam hardness tests. Halpin–Tsai and percolation model analyses of the results suggest that the crystalline regions exert a global influence on the elastomer structure.