Competitive hydrogen bonding mechanisms underlying phase behavior of triple poly(N-vinyl pyrrolidone)–poly(ethylene glycol)–poly(methacrylic acid-co-ethylacrylate) blends

Autor: Gary W. Cleary, Julia Kostina, G. A. Shandryuk, Parminder Singh, Galina N. Bondarenko, Polina E. Kireeva, Mikhail M. Feldstein
Rok vydání: 2007
Předmět:
Zdroj: Journal of Applied Polymer Science. 105:3017-3036
ISSN: 1097-4628
0021-8995
DOI: 10.1002/app.24502
Popis: Differential scanning calorimetry (DSC) of triple blends of high molecular weight poly(N-vinyl pyrrolidone) (PVP) with oligomeric poly(ethylene glycol) (PEG) of molecular weight 400 g/mol and copolymer of methacrylic acid with ethylacrylate (PMAA-co-EA) demonstrates partial miscibility of polymer components, which is due to formation of interpolymer hydrogen bonds (reversible crosslinking). Because both PVP and PMAA-co-EA are amorphous polymers and PEG exhibits crystalline phase, the DSC examination is informative on the phase state of PEG in the triple blends and reveals a strong competition between PEG and PMAA-co-EA for interaction with PVP. The hydrogen bonding in the triple PVP–PEG–PMAA-co-EA blends has been established with FTIR Spectroscopy. To evaluate the relative strengths of hydrogen bonded complexes in PVP–PEG–PMAA-co-EA blends, quantum-chemical calculations were performed. According to this analysis, the energy of H-bonding has been found to diminish in the order: PVP–PMAA-co-EA–PEG(OH) > PVP–(OH)PEG(OH)–PVP > PVP–H2O > PVP–PEG(OH) > PMAA-co-EA–PEG(O) > PVP–PMAA-co-EA > PMAA-co-EA–PEG(OH). Thus, most stable complexes are the triple PVP–PMAA-co-EA–PEG(OH) complex and the complex wherein comparatively short PEG chains form simultaneously two hydrogen bonds to PVP carbonyl groups through both terminal OH-groups, acting as H-bonding crosslinks between longer PVP backbones. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Databáze: OpenAIRE
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