In the realm of rubber materials, cross-linking density (CLD) plays a pivotal role in determining the overall performance and properties of the rubber. Actifine®, as a functionalized micronized rubber powder (FMRP), is a drop-in for many TRG applications thanks to it maintaining CLD and avoiding having to compensate for possible CLD changes by reformulating. In contrast, regular MRPs are associated with a significant reduction of CLD.
Why is CLD Crucial?
CLD is the “secret sauce” for high-performance rubber materials. It refers to the degree of chemical bonding between rubber macromolecules during vulcanization that gives the final product resilience, durability, and versatility. A well-cross-linked rubber matrix ensures enhanced mechanical properties, resistance to wear, improved ageing and thermal stability - making it a go-to for a myriad of applications from automotive to industrial. Positioning vulcanizates on the right spots of the CLD chart is an essential part of rubber product design.
What is the Advantage of Actifine® for CLD?
Actifine® is not your average MRP – it is a key factor for quality in sustainable rubber! Actifine® excels in maintaining CLD within rubber host compounds. Its unique surface functionalization and particle structure promote cross-linking without compromising structural integrity.
Our indirect measurements based on Delta S (MH-ML) of rheometer curves showed that comparable moduli are achievable, typically higher than 95 % of reference compound at around 15-20 wt.% Actifine® loading.
The lack of functionalization in traditional MRPs, on the other hand, leads to poor dispersion, higher viscosity, and weak interfaces making them a “stumbling block” and disrupting the cross-linking process, causing a reduction in CLD. This, in turn, compromises the rubber's performance in terms of elasticity, tensile strength, modulus, and wear resistance.
By incorporating Actifine® into your rubber formulations, you can unlock a new level of performance and durability, ensuring your products meet the demands of even the most challenging applications. With its ability to maintain CLD, Actifine® sets a new standard for rubber reinforcement, empowering you to make products that stand out in terms of quality, longevity, and overall performance.
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