Evaluation of Various Carbon Blacks in Highly Extended EPDM Compounds for Extrusion Applications

A three factor, multiple level, general factorial designed experiment was performed to investigate the subtleties of a highly extended EPDM formulation designed for the extrusion market.  The three factors were: 1) Carbon black – N550, N650, N774 and SR401, 2) Polymer type – Supplier A and B of 70 Mooney, 70/30 Ethylene to Propylene ratio, 5% ENB content, and 3) surface treatment – Yes or No.  This design yielded 16 discreet experiments in the data set.  Specific properties measured were:  a) physical properties, b) rheological properties, and c) dynamic properties.  The mathematical models generated from the designed experiment were employed to generate multiple solutions to various extrusion applications depending on customer criteria.  Also introduced is SR401, a new high structure carbon black which has many new properties not previously available to the custom rubber compounder and formulator.