Study of hydrogen-bonding strength in poly(?-caprolactone) blends by DSC and FTIR

The hydrogen-bonding strength of poly(ϵ-caprolactone) (PCL) blends with three different well-known hydrogen-bonding donor polymers [i.e., phenolic, poly(vinyl-phenol) (PVPh), and phenoxy] was investigated with differential scanning calorimetry and Fourier transform infrared spectroscopy. All blends exhibited a single glass-transition temperature with differential scanning calorimetry, which is characteristic of a miscible system. The strength of interassociation depended on the hydrogen-bonding donor group in the order phenolic/PCL > PVPh/PCL > phenoxy/PCL, which corresponds to the q value of the Kwei equation. In addition, the interaction energy density parameter calculated from the melting depression of PCL with the Nishi–Wang equation resulted in a similar trend in terms of the hydrogen-bonding strength. Quantitative analyses on the fraction of hydrogen-bonded carbonyl groups in the molten state were made with Fourier transform infrared spectroscopy for all systems, and good correlations between thermal behaviors and infrared results were observed. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 1348–1359, 2001

[1]  Z. Zhong,et al.  The miscibility and morphology of hexamine cross-linked novolac/poly(ϵ-caprolactone) blends , 1997 .

[2]  T. Kondo,et al.  Interchain Hydrogen Bonds in Blend Films of Poly(vinyl alcohol) and Its Derivatives with Poly(ethylene oxide) , 1999 .

[3]  M. Coleman,et al.  FTi.r. studies of polymer blends containing the poly(hydroxy ether of bisphenol A) and poly(ε-caprolactone) , 1983 .

[4]  P. Painter,et al.  Specific interactions and miscibility of polymer blends , 1995 .

[5]  T. Kwei.  The effect of hydrogen bonding on the glass transition temperatures of polymer mixtures , 1984 .

[6]  J. Hoffman,et al.  X‐Ray Study of Isothermal Thickening of Lamellae in Bulk Polyethylene at the Crystallization Temperature , 1965 .

[7]  K. Hikichi,et al.  High-resolution solid-state 13C nuclear magnetic resonance study of a polymer complex : poly(methacrylic acid)/poly(ethylene oxide) , 1996 .

[8]  Y. Mi,et al.  Solid-state n.m.r. investigation of crosslinkable blends of novolac and poly(ϵ-caprolactone) , 1999 .

[9]  Toshio Nishi,et al.  Melting Point Depression and Kinetic Effects of Cooling on Crystallization in Poly(vinylidene fluoride)-Poly(methyl methacrylate) Mixtures , 1975 .

[10]  Hew-Der Wu,et al.  Solid state NMR studies of hydrogen bonding network formation of novolac type phenolic resin and poly(ethylene oxide) blend , 2000 .

[11]  P. Flory.  Principles of polymer chemistry , 1953 .

[12]  M. Cortázar,et al.  Study of the melting and crystallization behavior of binary poly(.epsilon.-caprolactone)/poly(hydroxy ether of bisphenol A) blends , 1993 .

[13]  M. G. Prolongo,et al.  Melting behaviour and miscibility of poly(ϵ-caprolactone) + poly(4-hydroxystyrene) blends , 1996 .

[14]  M. Coleman,et al.  Concerning the miscibility of poly(vinyl phenol) blends — FTi.r. study , 1985 .