NOVEL APPROACH TO MEASURE CARBON BLACK STRUCTURE.

A void volume test to give quick and precise structure measurements on pelleted carbon black is described. The test has been developed using a modified capillary rheometer. The test procedure requires less than a gram sample of carbon black uses a single uniform procedure which is applicable to all grades of black and most important minimizes the effects of pelletizing treatment of the loose black. The test also eliminates the ″no end point DBP″ problem. The capillary rheometer was also utilized to obtain flow rate data on polymers before and after the addition of various grades of carbon blacks. The void volume data on a wide spectrum of carbon blacks has been correlated with the flow rate data, and in conjunction with tint and torque at 90% cure, to the performance properties in a SBR-1500, ASTM NR and SBR-1712 formulation.