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Updated: Jun 18, 2025
09:06
Evaluation of the Curing of Adhesive Systems by Rheological and Thermal Testing
Published on: July 3, 2020
7.2K
Influence of Rheological Modifications on Primary Network Chemical and Structural Cure Kinetics for an
Robert V Chimenti1,2, Kayla A Bensley1, Alexandra M Lehman-Chong2,3
1Department of Physics and Astronomy, Rowan University, Glassboro, New Jersey, USA.
Applied Spectroscopy
|August 2, 2024
Summary
Low-frequency Raman spectroscopy monitors resin cure kinetics by tracking structural changes, complementing traditional chemical conversion measurements. This technique reveals relationships between structural conversion and material properties, improving resin formulation and processing.
Area of Science:
- Polymer Science
- Materials Science
- Spectroscopy
Background:
- Non-contact in situ monitoring techniques enhance resin formulation and processing.
- Low-frequency Raman spectroscopy assesses resin structural cure kinetics.
- Structural cure kinetics complements traditional chemical conversion measurements.
Purpose of the Study:
- Evaluate the relationship between structural and chemical conversion in resin systems.
- Investigate two chemically identical but rheologically distinct interpenetrating polymer network (IPN) resin formulations.
- Correlate structural conversion with rheological properties like storage modulus.
Main Methods:
- Utilized low-frequency Raman spectroscopy for in situ monitoring of structural changes.
- Employed rheological analysis to measure storage modulus and assess material properties.
- Investigated two IPN resin formulations with identical chemistry but different rheology.
- Applied a semi-empirical model to analyze cure kinetics and storage modulus.
Main Results:
- Rheological analysis revealed a correlation between structural conversion and storage modulus, not evident in chemical conversion data.
- Master cure kinetics curves were generated using both chemical and structural conversion methods, yielding comparable kinetic constants.
- Demonstrated the utility of combining parametric analysis of different conversion types with modeling for storage modulus.
Conclusions:
- Low-frequency Raman spectroscopy provides valuable insights into structural cure kinetics, complementing chemical methods.
- Structural conversion is a critical factor influencing rheological properties during resin curing.
- The findings support the advancement of non-contact monitoring techniques for optimized resin formulation and processing.
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