Modeling of a two-stage polymerization considering glass fibre sizing using molecular dynamics

Area of Science:

• Materials Science
• Polymer Chemistry
• Computational Modeling

Background:

• Fiber reinforced polymers (FRPs) offer excellent mechanical properties but their performance is limited by poor understanding of the fiber-sizing-resin interface.
• Existing research often focuses on idealized systems, neglecting the complexity of industrial applications and the critical role of sizing agents.

Purpose of the Study:

• To develop and apply molecular dynamics simulations for studying complex sizing agent interactions at the fiber-sizing-resin interface in FRPs.
• To establish a systematic computational procedure for modeling the curing process of industrially relevant resin systems.

Main Methods:

• Utilized molecular dynamics simulations to model a simplified, industrially relevant resin system with added fiber surface and sizing layers.
• Modeled a two-stage curing reaction: initial condensation to form oligomers, followed by polyurethane reaction and radical polymerization.
• Performed spatial analysis of the fiber-sizing-resin interface by evaluating system properties along the normal direction to the fiber surface.

Main Results:

• Successfully extended a simplified resin system with fiber surface and sizing layers using molecular dynamics.
• Developed a systematic procedure to model the curing process, including condensation, polyurethane, and radical polymerization reactions.
• Enabled spatial analysis of the fiber-sizing-resin interface, providing insights into interfacial behavior.

Conclusions:

• The developed molecular dynamics approach provides a valuable method for studying complex fiber-sizing-resin interactions in industrially relevant systems.
• This work lays the foundation for optimizing sizing agent design and improving the overall performance of fiber reinforced polymers.