Graft interpenetrating polymer networks of polyurethane and epoxy containing rigid rods in side chain

• Published in: Journal of applied polymer science Vol. 106; no. 5; pp. 3298 - 3307
• Main Authors: Han, J.L, Lin, S.P, Ji, S.B, Hsieh, K.H
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 05-12-2007; Wiley
• Subjects: Applied sciences; Chains (polymeric); compatibililty; epoxy; Exact sciences and technology; Fracture mechanics; grafted‐interpenetrating polymer networks (graft‐IPNs); Grafting; Interpenetrating networks; liquid crystal polymer (LCPs); mechanical property; Morphology; Organic polymers; Phase separation; Physicochemistry of polymers; Polymers; Polymers with particular properties; polyurethane (PU); Polyurethane resins; Preparation, kinetics, thermodynamics, mechanism and catalysts; Graft copolymer; polyurethane (PU); epoxy; Thermotropic state; Epoxy resin; Mechanical properties; Tensile property; mechanical property; Experimental study; Urethane copolymer; compatibililty; Polyaddition; Interpenetrating polymer network; Thermal properties; Biphenyl derivatives; Liquid crystal polymers; Impact strength; grafted-interpenetrating polymer networks (graft-IPNs); Morphology; Property structure relationship; liquid crystal polymer (LCPs); Fracture mode
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.26874

The rigid rod-like 4,4'-bis(6-hydroxyhexyloxy)biphenyl (BHHBP) units were distributed in either the epoxy or polyurethane to become SR-epoxy and PU (with or without BHHBP) polymer matrices. The interpenetrating polymer networks (IPNs) of PU (with or without BHHBP) and SR-epoxy were synthesized through simultaneous polymerization, and connected each other via the grafting reaction between the ---NCO groups of the PU polymer network and the ---OH groups on the side chains of SR-epoxy network. The thermal and mechanical characteristics, compatibilities, and morphologies of these PU (with or without BHHBP)/SR-epoxy graft-IPNs were investigated. The polyether-type PU(PPG series)/SR- epoxy graft-IPNs exhibited two-phased morphologies (i.e., phase separation occurred), and higher fracture energies (GIC). Whereas the polyester-type PU(PBA series)/SR- epoxy graft-IPNs were homogeneous (no phase separation), and exhibited higher tensile and Izod impact strengths. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007