Novel michael addition networks containing urethane hydrogen bonding

• Published in: Journal of polymer science. Part A, Polymer chemistry Polymer chemistry, 2007-09, Vol.45 (17), p.4118-4128
• Main Authors: Williams, Sharlene R., Mather, Brian D., Miller, Kevin M., Long, Timothy E.
• Format: Article
• Language: English
• Subjects: Applied sciences; Chemical reactions and properties; crosslinking; Crosslinking, vulcanization; Exact sciences and technology; hydrogen bond; mechanical properties; Michael addition; Organic polymers; Physicochemistry of polymers; thermal properties
• ISSN: 0887-624X; 1099-0518
• DOI: 10.1002/pola.22236

Covalently crosslinked networks based on poly(propylene glycol) bis(acetoacetate) with either neopentyl glycol diacrylate or hydroxyethyl acrylate derivatized bis(4‐isocyanatocyclohexyl)methane (HMDI) were prepared utilizing the Michael addition reaction in the presence of catalytic quantities of diazabicyclo[5.4.0]undec‐7‐ene (DBU). These networks were prepared in the absence of solvent at 23 °C without the formation of byproducts. Mechanical and thermal analyses of the networks were performed utilizing DMA, tensile testing, and TGA. Tensile analysis revealed that the introduction of hydrogen‐bonding urethane linkages in the diacrylate segment resulted in higher tensile strengths and elongation to break compared with nonhydrogen‐bonding analogs. All crosslinked products exhibited high gel fractions and excellent thermomechanical properties. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4118–4128, 2007 The Michael addition reaction was utilized to prepare covalently crosslinked networks based on poly(propylene glycol) bis(acetoacetate) with either neopentyl glycol diacrylate or hydroxyethyl acrylate derivatized bis(4‐isocyanatocyclohexyl)methane (HMDI). These networks were prepared in the presence of catalytic quantities of diazabicyclo[5.4.0]undec‐7‐ene (DBU) in the absence of solvent at 23 °C without the formation of byproducts. Mechanical and thermal analyses of the networks were performed utilizing DMA, tensile testing, and TGA. Higher tensile strengths and elongation to break compared with nonhydrogen‐bonding analogs resulted when hydrogen‐bonding urethane linkages were introduced in the diacrylate segment.