Simulated morphological landscape of polymer single crystals by phase field model

Area of Science:

• Materials Science
• Computational Physics
• Polymer Science

Background:

• Understanding polymer single crystal growth is crucial for materials science.
• Existing models often simplify crystal growth dynamics.
• The specific characteristics of polymer crystallization require advanced modeling approaches.

Purpose of the Study:

• To develop a novel phase field model incorporating polymer characteristics.
• To simulate the spatiotemporal growth of syndiotactic polypropylene single crystals.
• To elucidate the physical origins of polymer single crystal morphology.

Main Methods:

• Established a phase field model based on the nonconserved spatiotemporal Ginzburg-Landau equation (TDGL model A).
• Related diffusion equations to polymer crystal growth faces, discretizing diffusion coefficients for lattice sites.
• Utilized two-dimensional numerical calculations with lattice shapes reflecting unit cell dimensions.

Main Results:

• Simulated the growth of faceted single crystals, including square, rectangular, lozenge-shaped, and hexagonal morphologies.
• Demonstrated good agreement between simulated patterns and experimental polymer crystal morphologies.
• Provided theoretical insights into the physical mechanisms driving polymer single crystal growth.

Conclusions:

• The developed phase field model effectively captures polymer-specific characteristics in crystal growth.
• The model's predictions align well with experimental observations, validating its approach.
• This work enhances the theoretical understanding of polymer crystallization and morphology development.