An eco-friendly, high-yield and scalable method for processing concentrated natural rubber latex with superabsorbent polymer beads

Concentrated natural rubber latex (CNRL), prized for its exceptional molding performance, high elasticity and strength, is indispensable in various latex products. Currently, commercial CNRL production mainly relies on the centrifugation of fresh natural rubber latex (FNRL), facing challenges such as complexity, lower yield and environmental pollution. In this study, an absorption concentration method based on superabsorbent polymer (SAP) beads was developed for fabricating CNRL to overcome these limitations, without using complex equipment. The concentration process is more environmentally friendly and is applicable to the concentration of various synthetic rubber latexes. The CNRL prepared through this method can achieve a total solid content of up to 70 % and exhibits excellent storage stability. Furthermore, the substantial non-rubber components in CNRL markedly improve the mechanical attributes of the resulting products, including rubber films and latex products. The absorption mechanism of SAP beads on non-rubber components has been subjected to comprehensive analysis, thereby providing substantial theoretical support for the comprehension of this process. This work not only successfully identifies a highly promising method for natural rubber latex concentration but also establishes a robust theoretical foundation for subsequent process optimization.