Time‐Resolved Infrared Spectroscopic Characterization of Curing Kinetics for Silyl‐Modified Preceramic Polymers

Extreme environments, such as those experienced in aerospace and at hypersonic speeds, challenge the performance of conventional materials and motivate the development of advanced ceramics with low density, erosion/corrosion resistance, and high modulus. Traditional ceramic processing often results in brittle, porous structures that are constrained by mold geometry and have limited design flexibility. Preceramic polymers (PCP) address these limitations by enabling the fabrication of complex shapes via advanced manufacturing and the reduction of porosity via polymer infiltration and pyrolysis (PIP) cycles. Crucial to the efficiency of PIP is the ceramic yield, which is greatly affected by PCP curing. This study investigates the thermal curing behavior of StarPCS silyl‐modified polymers SMP‐10 and SMP‐877. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR‐FTIR) was used to track changes in the absorbance of key functional groups to monitor chemical transformations under an inert argon atmosphere. The curing process, driven by hydrosilylation, was modeled as an irreversible first‐order reaction, with normalized peak areas representing concentration. Curing rate constants and activation energies were quantified. Crosslinking was found to occur primarily between 150 °C and 250 °C. This study provides insight into improving the rate and energy efficiency of advanced ceramic production.