Reversible Diels-Alder chemistry was utilized to manipulate the surface energy of glass substrates. Hydrophobic dieneophiles were prepared and attached to glass slides and capillaries to yield a nonwetting surface. Thermal treatment of the surfaces cleaved the Diels-Alder linkage, and resulted in the fabrication of a hydrophilic surface. Preliminary analysis utilized contact angle (CA) measurements to monitor the change in surface energy, and observed a hydrophilic state (CA - 70 +/- 3 degrees) before attachment of the dieneophile to a hydrophobic state (CA - 101 +/- 9 degrees) followed by regeneration of the hydrophilic state (CA - 70 +/- 6 degrees) upon cleavage of the Diels-Alder linkage. The treatments were then applied to glass capillaries, with effective treatment confirmed by fluid column measurements. Patterned treatments were also demonstrated to provide effective flow gating. Finally, attempts to create self-pressurizing capillaries were unsuccessful due to pronounced contact angle hysteresis for the hydrophobic surface treatment.

A soybean based coating with thermally responsive Diels-Alder linkages has been prepared following an automotive 2-component formulation. The resulting coatings displayed the capability to be healed following physical deformation by a thermal stimulus, and such a material has significant potential for end users. Various curing agents were employed, and resulted in variation of scratch resistance and re-healablity. Different thermally responsive soybean resins were synthesized to have varying amounts reversible and nonreversible linkages when incorporated into the coating. Additionally, different isocyanates were added at differing ratios of NCO : OH in search of the optimum coating. It was found through the analysis of rehealability, hardness, gloss, and adhesion that the optimal combination was an acetylated resin (no irreversible crosslinks) with 54% reversible Diels-Alder linkages at an NCO : OH ratio of 5 : 1 using isophorone diiscocyanate. Materials were evaluated via differential scanning calorimetry (DSC), scratch resistance, Koenig hardness, gloss measurements, and topographical analysis.

The corrosion of infrastructure imposes a significant monetary cost, and at times human cost, upon society. Methods to improve corrosion resistance of materials are described herein which utilize the reversibility of the Diels-Alder reaction to impart thermal responsiveness upon materials. Such stimuli responsiveness can potentially play a role in self healing properties which lead to reduced cracking and thus increased corrosion protection.