Related Experiment Video
Updated: May 14, 2025
09:06
Evaluation of the Curing of Adhesive Systems by Rheological and Thermal Testing
Published on: July 3, 2020
6.3K
Correlation Between the Molecular-Level Behavior of Polyurethane on Oily Surfaces and Adhesive Strength
Seito Yamazaki1, Takahiro Aizawa2, Takayuki Miyamae1,3,4
1Graduate School of Science and Engineering, Chiba University, 1-33 Inage-ku, Chiba, Chiba 263-8522, Japan.
ACS Omega
|May 12, 2025
Summary
Understanding how silicone oil affects polyurethane adhesive bonds is key for industrial applications. This study reveals oil absorption during curing and reappearance upon heating weakens adhesion, offering insights for stronger bonds on oily surfaces.
Area of Science:
- Materials Science
- Surface Chemistry
- Polymer Science
Background:
- Adhesive bonding is vital in automotive and aerospace industries.
- Polyurethane adhesives offer room-temperature curing, flexibility, and insulation.
- Bonding without degreasing oily surfaces is a significant industrial challenge.
Purpose of the Study:
- To elucidate the molecular behavior of silicone oil at polyurethane interfaces.
- To investigate the impact of oil behavior on adhesive bond strength.
- To provide insights for developing adhesives for oily substrates.
Main Methods:
- Utilized vibrational sum frequency generation (SFG) spectroscopy.
- Investigated the correlation between silicone oil behavior and adhesion strength.
- Examined oil migration during room-temperature curing and thermal annealing.
Main Results:
- Silicone oil is absorbed into the polyurethane bulk during room-temperature curing.
- Annealing causes absorbed silicone oil to reappear at the interface.
- The reappearance of silicone oil at the interface significantly reduces adhesion strength.
Conclusions:
- Silicone oil's solubility and migration behavior dictate adhesion on oily surfaces.
- Understanding oil-polymer interactions is crucial for reliable bonding.
- Findings guide the design of polyurethane adhesives for enhanced performance on oil-contaminated substrates.
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