Thermodynamic hydrogen bonding inpoly(styrene‐co‐acrylic acid)/poly(styrene‐co‐4‐N,N‐dimethylacrylamide) blends

Abstract

FTIR study of the hydrogen bonding interactions within blends of different ratios of poly(styrene-co-acrylic acid) containing 18, 27, and 32 mol% of acrylic acid (SAA) and poly(styrene-co-N,N-dimethylacrylamide) containing 17 mol% of N,N-dimethylacrylamide (SAD-17) was carried out qualitatively and quantitatively in the temperature range varying from room temperature to 2108C. Two new bands characterizing these interactions appeared in the 1800-1550 cm -1 region at 1730 cm -1 and 1616 cm -1 and are attributed to ''liberated'' carbonyl group of the acidic copolymer and the ''associated amide'' carbonyl group, respectively. Equilibrium constants describing both the self-association K 2 and inter-association K A and the enthalpy of hydrogen bonding formation in the different blends were experimentally determined using a curve fitting analysis of the infra-red spectra as a function of temperature using the appropriate equations derived from the Painter-Coleman association model. The obtained results confirm the miscibility of these blends in the considered temperature range from the negative values of the total free energy of mixing DG M . Optimization of the extent of intermolecular interactions between the two polymers in these blends is investigated.

Interpolymer Complexes of Poly(N,N‐Dimethylacrylamide/Poly(Styrene‐co‐Acrylic Acid): Thermal Stability and FTIR Analysis

“…The same study also confirmed that spacing the carboxylic groups within polystyrene matrix optimized the hydrogen bonding interactions in poly (styrene‐co‐acrylic acid)/poly (styrene‐co‐N, N‐dimethylacrylamide) homoblends 19…”

“…It is worth recalling that we previously showed19 that while SAA18/SAD17 formed homogeneous phase in butan‐2‐one, turbid solutions were observed in the same common solvent with SAA32/SAD17 systems. All these blends, as‐cast from butan‐2‐one, exhibited a single Tg.…”

“…These copolymers were purified by repeated dissolution/precipitation in THF/methanol and to remove the residual solvent they were then dried to constant weight in a vacuum oven for several days at 60 °C. They were characterized as previously described18–20 by elemental analysis, UV spectroscopy and proton NMR. Their average molecular weights were examined by size exclusion chromatography using a Waters HPLC (elution with THF on cross‐linked polystyrene: rate 1 ml/min, calibration with polystyrene standards).…”

Self‐Healing Micellar Ion Gels Based on Multiple Hydrogen Bonding

“…It should be also noted that the hydrogen bonding between the two AAc units is also possible. Nevertheless, the dimethylamide group is well‐known as a strong hydrogen bonding acceptor, and as much more DMAAm units exist in the ion gel than AAc units, the hydrogen bonding between DMAAm and AAc groups would be dominant …”

A thermodynamic analysis of specific interactions in blends of poly(styrene‐co‐N,N‐dimethylacrylamide) and poly(styrene‐co‐acrylic acid). Screening and self‐association effects

“…In a previous article,13 we have used FTIR spectroscopy to study the hydrogen bonding interactions within homoblends of poly(styrene‐ co ‐acrylic acid) containing 18, 27, and 32 mol % of acrylic acid (SAA18, SAA27, and SAA32, respectively) and poly(styrene‐ co ‐ N,N ‐dimethylacrylamide) containing 17 mol% of N,N ‐dimethylacrylamide (SAD17). Equilibrium constants describing both self‐association K 2 and interassociation K A and the enthalpies of hydrogen bonding formation were experimentally determined using a curve fitting analysis of the FTIR spectra as a function of temperature.…”