Thermally accelerated curing of platinum-catalyzed elastomers

• Published in: Cell reports physical science 2024-03, Vol.5 (3), p.101849, Article 101849
• Main Authors: Yap, Te Faye, Rajappan, Anoop, Bell, Marquise D., Rasheed, Rawand M., Decker, Colter J., Preston, Daniel J.
• Format: Article
• Language: English
• Subjects: Arrhenius relationship; curing; manufacturing; reaction kinetics; silicone; soft robotics; temperature
• ISSN: 2666-3864; 2666-3864
• DOI: 10.1016/j.xcrp.2024.101849

Silicone elastomers exhibit extraordinary compliance, positioning them as a material of choice for soft robots and devices. To accelerate curing times of platinum-catalyzed silicone elastomers, researchers have employed elevated temperatures; however, knowledge of the requisite duration for curing at a given temperature has remained limited to specific elastomers and has relied primarily on empirical trends. This work presents an analytical model based on an Arrhenius framework coupled with data from thermo-rheological experiments to provide guidelines for suitable curing conditions for commercially available addition-cured platinum-catalyzed silicone elastomers. The curing reaction exhibits self-similarity upon normalizing to a dimensionless reaction coordinate, allowing quantification of the extent of curing under arbitrary time-varying thermal conditions. Mechanical testing revealed no significant changes in properties or performance as a result of thermally accelerated curing. With this framework, higher throughput of elastomeric components can be achieved, and the design space for elastomer-based manufacturing can be developed beyond conventional casting. [Display omitted] •Elevated temperatures (T) accelerate curing of Pt-catalyzed silicone elastomers•Parameters for curing are often determined empirically without physical insight•We develop a model that determines the gelation time as a function of T•Self-similarity allows prediction of the cure extent for arbitrary T versus time Yap et al. introduce and validate a modeling framework that describes the temperature-dependent curing of platinum-catalyzed silicone elastomers under arbitrary spatiotemporal thermal conditions. The presented framework enables tunable curing via modulation of temperature and yields orders of magnitude higher throughput of elastomeric components compared to room temperature curing.