Chemically induced transition phenomena in polyurethanes as seen from generalized mode Grüneisen parameters

Area of Science:

• Polymer Chemistry
• Materials Science
• Physical Chemistry

Background:

• Phenomenological properties of reactive polymers, such as polyurethanes, change continuously during curing.
• These changes are linked to irreversible phase transitions, sol-gel transitions, and chemically induced glass transitions.
• The underlying curing process often obscures these critical transition phenomena.

Purpose of the Study:

• To propose generalized mode Grüneisen parameters as a novel method for investigating polymerization processes.
• To elucidate closely related transition phenomena during polymer curing.
• To utilize these parameters to better understand the curing behavior of reactive polymers.

Main Methods:

• Utilizing generalized mode Grüneisen parameters as an analytical probe.
• Employing polyurethane as a model system, synthesized from diisocyanate and varying ratios of difunctional and trifunctional alcohols.
• Monitoring changes in phenomenological properties during the curing process.

Main Results:

• Generalized mode Grüneisen parameters provide a sensitive measure of polymerization progress.
• This approach can reveal phase transitions that are otherwise masked by the curing process.
• The study demonstrates the utility of Grüneisen parameters in characterizing complex polymer curing dynamics.

Conclusions:

• Generalized mode Grüneisen parameters are effective in elucidating polymerization and associated transition phenomena.
• This method offers an alternative to traditional property measurements for studying reactive polymers.
• The findings contribute to a deeper understanding of polyurethane curing and related material science principles.