An Investigation of the Dynamic Curing Behavior and Micro-Mechanism of a Super-Tough Resin for Steel Bridge Pavements

To overcome challenging service conditions, a groundbreaking thermoset, "Super-Tough Resin" (STR), has been specifically designed for steel bridge deck paving. Currently, investigations of paving thermosets mainly focus on cured materials. Detailed investigations of the curing process and its impact on the evolving properties of STR are lacking. Therefore, this study aims to explore the curing kinetics and the performance evolution of STR. Specifically, spectroscopy test, time sweep, linear viscoelastic region, and weight loss tests were conducted. Our results show that the curing degrees increase significantly with the curing durations and temperatures at the initial stage. When cured for 10 h, the curing degrees at four temperatures all exceed 80%. Then, a kinetic model with an nth-order of 1.551 was established. Upon increasing the temperature from 35 to 80 degrees C, the gel point time decreases from 480 to 189 min but the corresponding curing degree remains constant at 75.73%. When curing time is increased from 2.5 to 4 h, the linear viscoelastic regions decrease from 20% to 3%. Finally, after 400 h, the weight losses of STR at 35 and 80 degrees C are about 8% and 20%, respectively. These outcomes are beneficial to understanding the dynamic curing behaviors of STR and similar thermosets.