Heterogeneity of glass transition dynamics in polyurethane‐poly(2‐hydroxyethyl methacrylate) semi‐interpenetrating polymer networks

• DOI: 10.1002/polb.21108
• Publication Date: 2007-03-02T01:50:49Z
• Authors: L. V. Karabanova; L. M. Sergeeva; A. V. Svyatyna; P. N. Yakushev; L. M. Egorova; V. A. Ryzhov; V. A. Bershtein
• Keywords: Interpenetrating polymer network

Abstract The peculiarities of segmental dynamics over the temperature range −140 to 180 °C were studied in polyurethane‐poly(2‐hydroxyethyl methacrylate) semi‐interpenetrating polymer networks (PU‐PHEMA semi‐IPNs) with two‐phase, nanoheterogeneous structure. synthesized by sequential method when PU network was obtained from poly(oxypropylene glycol) (PPG) and adduct trimethylolpropane (TMP) toluylene diisocyanate (TDI), then swollen 2‐hydroxyethyl methacrylate monomer its subsequent photopolymerization. PHEMA content semi‐IPNs varied 10 57 wt %. Laser‐interferometric creep rate spectroscopy (CRS), supplemented differential scanning calorimetry (DSC), used for discrete dynamic analysis these IPNs. effects anomalous, large broadening glass transition higher temperatures comparison that neat PHEMA, despite much lower T g constituent, pronounced heterogeneity found networks. Up 3 or 4 overlapping peaks, characterizing different modes, have been registered within both transitions semi‐IPNs. On whole, united semi‐IPN ranged virtually −60 160 °C. As proved IR spectra, some hybridization constituents took place, therefore observed could be properly interpreted framework notion “constrained dynamics.” peculiar may help developing advanced biomedical, damping, membrane materials based thereon. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Phys 45: 963–975,