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Published on: August 13, 2020
Exploring the impact of weak interaction on conformational flexibility in polyborosiloxane
Yang Song1, Zhiming Zhao1, Feng Li1,2
1School of Materials Science and Engineering, Xi'an University of Technology, Xi'an 710048, China. leo1981_0804@163.com.
Physical Chemistry Chemical Physics : PCCP
|July 27, 2026
Summary
Intramolecular hydrogen bonds critically influence the flexibility of polyborosiloxane (PBS) polymers. This study reveals these weak interactions are key to PBS
Area of Science:
- Polymer Chemistry
- Materials Science
- Computational Chemistry
Background:
- Weak interactions, such as hydrogen bonds, are fundamental in determining polymer properties.
- Polyborosiloxane (PBS) is a supramolecular polymer known for its shear-stiffening behavior.
- Understanding the role of weak interactions in PBS is crucial for tailoring its properties.
Purpose of the Study:
- To investigate the influence of weak interactions on the conformational flexibility of polyborosiloxane (PBS).
- To establish a robust computational protocol for studying complex polymer systems.
- To provide fundamental insights into the physicochemical properties of PBS isomers.
Main Methods:
- Synthesis of polyborosiloxane (PBS) samples with varying molecular weights via condensation reaction.
- Characterization using Gel Permeation Chromatography (GPC) and Fourier-Transform Infrared (FTIR) spectroscopy.
- Multi-level computational approach: high-temperature molecular dynamics, semi-empirical pre-screening, and DFT calculations for low-energy conformer identification.
- Advanced wavefunction analyses: IRI, energy decomposition, atomic charge, and ESP mapping to characterize weak interactions.
- Frequency calculations to confirm optimized structures as true minima.
- Thermodynamic calculations to assess conformer stability.
Main Results:
- Experimental characterization confirmed the successful synthesis of PBS with minimal side reactions.
- Computational methods identified low-energy conformers of PBS.
- Advanced wavefunction analyses revealed that intramolecular hydrogen bonds are the primary drivers of PBS conformational flexibility.
- Thermodynamic calculations supported the stability of identified conformers.
Conclusions:
- Intramolecular hydrogen bonds play a critical role in modulating the conformational flexibility of polyborosiloxane (PBS).
- The study establishes a comprehensive and integrated computational protocol for analyzing weak interactions in complex polymer systems.
- The findings offer fundamental insights into the structure-property relationships of PBS, paving the way for tailored material design.
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