Accelerators Derived from Piperidine

Abstract

Abstract Before the year 1913 piperidine was a compound of little more than academic interest and seldom to be found in considerable quantities outside the chemical laboratory. At about that time it became known that many organic bases, and in particular, piperidine and its homologs, had the effect of accelerating the vulcanization of rubber. Had piperidine then been available at a reasonable price, there is no doubt that large quantities would have been absorbed by the rubber industry. Apart from the high cost of the material, however, piperidine and other bases were not free from the objection that they were volatile and unpleasant to handle in the ordinary mixing process. In the light of modern standards, the degree of acceleration imparted by these bases would be regarded as being of a low order. In those days, however, the effect had a considerable practical significance. In attempting to make use of these bodies in a more convenient form, it was subsequently shown that the compounds formed by the reaction of carbon disulfide with aliphatic amines had an accelerating effect that was much more intense than that of the amine itself. In particular, the product obtained from the reaction of piperidine with carbon disulfide, namely, piperidyl pentamethylenedithiocarbamate (P.P.D.), was found to have exceptionally useful properties. It is probably true to say that this product was the first ultra-accelerator to acquire commercial importance.