Standard Malaysian rubber L (SMR L)

This rubber, known as SMR L, is a pristine light-colored material. To prevent enzyme darkening, 0.05% of sodium metabisulfate is included during the latex stage. SMR L is mainly utilized in colored compounds, particularly light or vibrant hues. Its consistent and clean nature allows for reduced colorant usage while enhancing color uniformity between batches (ensuring this week’s color matches that made six months from now! ). General-purpose rubber lacks this consistent quality. The low presence of impurities also contributes to high-quality physical properties. While some may opt for the slightly cheaper SMR 5 for solely physical properties, SMR L is preferred for comprehensive requirements to avoid stocking multiple versions of the same product.

Utilizing a precrosslinked rubber, whether natural or synthetic, offers several processing benefits. Precrosslinked natural rubber enhances processing without compromising final properties. When blended with SBR, it not only enhances physical properties but also improves processing efficiency, similar to the effect of adding NR to SBR.