Crystallization Kinetics and Thermodynamic Parameters of Poly(thioglycolide)

Area of Science:

• Polymer Science
• Materials Chemistry
• Chemical Engineering

Background:

• Limited understanding of thermodynamic parameters and condensed-state structures in closed-loop recyclable polymers.
• Poly(thioglycolide) (PTGC) is a promising material for closed-loop chemical recycling.
• Need for detailed characterization of PTGC's properties to facilitate its application.

Purpose of the Study:

• Investigate the thermodynamic properties and crystallization kinetics of poly(thioglycolide) (PTGC).
• Determine the optimal crystallization temperature and understand the influence of molecular weight.
• Establish fundamental thermodynamic data for PTGC to aid in its recycling and material design.

Main Methods:

• Differential Scanning Calorimetry (DSC) for thermal analysis.
• Fast Scanning Chip Calorimetry (FSC) for crystallization kinetics.
• Wide-Angle X-ray Diffraction (WAXD) for structural analysis.
• Hoffman-Weeks extrapolation for equilibrium melting point determination.

Main Results:

• Identified an optimal crystallization temperature of 80 °C for PTGC, distinguishing homogeneous and heterogeneous crystallization.
• Determined the heat of fusion to be 123 ± 10 J/g, independent of molecular weight.
• Calculated equilibrium melting points of 211 ± 2 °C and 280 ± 2 °C using linear and nonlinear Hoffman-Weeks methods.

Conclusions:

• Established key thermodynamic parameters and crystallization behavior of PTGC.
• Provided fundamental data crucial for the design and efficient chemical recycling of PTGC.
• Highlighted the potential of PTGC as a recyclable polymer with well-defined properties.