The Novel Use of Controlled Long Chain Branched (CLCB) Keltan~R Blends to Widen the Processing Window

摘要

Combinations of new CLCB EPDM grades are used showing the advantages to be gained fay blending. Previous papers have described the intrinsic properties of EPDMs produced using the CLCB polymerisation technology with respect to compound behaviour and physical properties. The EPDM molecular structure is described in terms of chemical composition, Mooney viscosity (molecular weight), molecular weight distribution and a long chain branching parameter AS. This recently introduced family of EPDM polymers shows a molecular structure that differs significantly from conventional EPDMs in their balance of molecular weight distribution and long chain branching. This is manifested in lower Mooney viscosity, retention of physical properties despite predominance of low molecular weight polymer contribution, cure rate and processing safety. The presentation will offer guidelines for formulating blends for specific applications and processing constraints.