Influence of a metallic filler on polyurethane formation

The addition of metallic fillers is recognized to impart improvement of acoustic properties to polyurethane‐based materials used for marine applications. The system under consideration was obtained by the reaction of a triisocyanateterminated prepolymer with 1,4‐butanediol, in the presence of various concentrations of lead powder. With increasing lead content, gelation time is reduced and an Einstein‐type law does not apply. The kinetics of the reaction were determined by Fourier transform infrared spectroscopy. Deviation from the classic second order is observed for the filled systems, and the higher the lead content, the more important the deviation is, showing undoubtedly the catalytic effect of the metallic powder.