Polymer additives for rubber compounds

Improving rheology and processing: Smoother surfaces, reduced friction

Traditional process aids/lubricants are surface active substances that reduce the interfacial tension between surfaces, but this often leads to softening of the compound and reduction of physical properties, thermal ageing and oil/chemical resistance. Our alternative is 'the SIDISTAR™ way', using spherical particles, which reduce friction by minimizing the contact area between surfaces. When the particles are small enough, like the 150 nm particles of SIDISTAR™ product, only limited effects on properties can be expected.

Our product SIDISTAR™ offers improved processing and surface finish. These effects can be obtained both in rubbers as well as in thermoplastic compounds. Our customers use these properties in applications like cable compounds, flame retardant compounds, conveyor belts, as well as printer rolls.

The SIDISTAR™ 'ball bearing effect' has clear advantages for both cured and uncured compounds. Significant improvements in mixing energy and efficiency are seen, and there are cases where the number of mixing cycles could be reduced from three to two, at the same time as improving compound homogeneity.

Improving dynamic fatigue

By adding SIDISTAR™ additive to an elastomeric compound, you can achieve improvement of dynamic fatigue life up to 30–50%. These results can be obtained in a wide range of elastomers, such as NR, EPDM, BIIR and even FKM.

The fatigue improvement originates in the spherical shape and capability of dispersing down to primary particles. The primary particles in SIDISTAR™ have a mean size of 150 nm. The most commonly used SIDISTAR™ dosage, for these fatigue life improvements, lays in the range of 10–15 phr. There is little to no influence observed for physical properties and hardness of the final product.

Today, SIDISTAR™ is mainly used for its fatigue-enhancing properties in applications like anti-vibration pads, bushings and power transmission belts.

Improving flame retardancy

Whether you work with a flame-retardant system that relies on halogenated additives, or whether you prefer halogen-free systems,  SIDISTAR™ additives can help you to find improved solutions.

Our product SIDISTAR™ acts as a synergist together with primary flame-retardant materials, to improve the morphology for improved char integrity.

 

 

Improving fiber dispersion for faster processing

Incorporation of fibers into polymeric compounds can be a challenge, because they often remain floating on top of the compound and take a long time to incorporate and become fully 'wetted'.

By dry-blending fibres with SIDISTAR™, the incorporation is made a lot easier and at the same time the spherical particles result in a 'ball bearing' functionality, improving the processability of the final compound. This results in faster mixing, better anisotropic behavior, improved process ability, and improved product surface finish.

 

 

Improving special FKM compounds

FKM elastomers are a special case in the rubber world. Unlike other rubber compounds, SIDISTAR™, with its very low specific surface of 20–30 m²/g, acts as a reinforcing filler for FKM elastomers.

SIDISTAR™ is capable of replacing N990 on a 1:1 basis. Physical properties will remain very similar, but dynamic fatigue properties will improve. Since SIDISTAR™ also has grades with an off-white colour, it allows production of coloured FKM compounds without compromising physical properties.

 

 

Polymer additives: Maintaining Elkem’s leadership through sustainable technology

Polymer additives and rubber product formulations are constantly evolving, driven by a need for greater energy efficiency, cost-effectiveness and sustainability requirements, including longer lifecycles and recyclability.