Theoretical study of hydrogen bonding interactions on MDI-based polyurethane
Cuili Zhang1, Jinlian Hu, Shaojun Chen
1Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, China.
Journal of Molecular Modeling
|February 16, 2010
Summary
Density functional theory (DFT) investigated hydrogen bonding in MDI-based polyurethane. DFT confirmed hydrogen bonds form between carbonyl/ester and N-H groups, with carbonyl bonds being stronger.
Area of Science:
- Materials Science
- Computational Chemistry
- Polymer Science
Background:
- Polyurethanes are versatile polymers with applications in various industries.
- Understanding hydrogen bonding is crucial for predicting polyurethane properties.
- 4,4'-diphenylmethane diisocyanate (MDI)-based polyurethanes are widely used.
Purpose of the Study:
- To theoretically investigate hydrogen bonding in MDI-based polyurethane.
- To explore interactions between hard-hard and hard-soft segments.
- To validate computational methods for studying weak interactions in polymers.
Main Methods:
- Density Functional Theory (DFT) calculations were employed.
- B3LYP/6-31G* and B3PW91/6-31G* computational methods were utilized.
- Analysis of molecular structures, charges, binding energies, dipole moments, and IR spectra.
Main Results:
- DFT methods accurately predicted molecular structures and hydrogen bonding characteristics.
- Calculated N-H...O bond distances closely matched experimental data.
- Polyurethane carbonyl oxygen predominantly exists in a hydrogen-bonded state.
- Carbonyl hydrogen bonds were found to be stronger than ester hydrogen bonds.
Conclusions:
- DFT is a reliable tool for studying weak interactions in MDI-based polyurethane.
- Hydrogen bonds form between carbonyl/ester groups and N-H groups.
- The strength of hydrogen bonds influences the material's properties.
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