INFLUENCE OF A METALLIC FILLER ON POLYURETHANE FORMATION

The addition of metallic fillers is recognized to impart improvement o f acoustic properties to polyurethane-based materials used for marine applications. The system under consideration was obtained by the react ion of a triisocyanate-terminated prepolymer with 1,4-butanediol, in t he presence of various concentrations of lead powder. With increasing lead content, gelation time is reduced and an Einstein-type law does n ot apply. The kinetics of the reaction were determined by Fourier tran sform infrared spectroscopy. Deviation from the classic second order i s observed for the filled systems, and the higher the lead content, th e more important the deviation is, showing undoubtedly the catalytic e ffect of the metallic powder.