An oil-extended EPDM rubber (Keltan 7341 A, a new CLCB grade rubber) with ethylene-norbornene (7.5 wt%), oil (20 phr), Mooney viscosity 53 at 150[degrees]C, obtained from DSM, Netherlands was used.
NOMENCLATURE ATH Aluminum hydroxide CBS Cyclohexyl benzothiazole sulphonamide CLCB Conjugated long chain branching EPDM Ethylene-propylene-diene monomer HAF High abrasion furnace HB Horizontal burning LOI Limiting oxygen index phr Parts per hundred rubber S Sulfur SEM Scanning electron microscopy TGA Thermogravimetric analysis TMTD Tetramethylthiuram disulfide ZnO Zinc oxide Correspondence to: Rani Joseph; e-mail: firstname.lastname@example.org
Again, the CLCB technology showed the best overall performance, resulting in the most consistent production process and product properties.
To validate the CLCB structure and composition of the new sponge polymer, it was decided to compare K7341A with two EPDMs exhibiting significantly different polymer characteristics.
In addition, the level of CLCB improves the surface finish of extruded profiles.
The robustness of the CLCB production technology offers a product with a high level of consistency, which is required for the production of automotive sponge seals.
The branching level of CLCB polymers can be tuned to optimize processing behavior without disturbing physical properties.