Sodium Thiosulfate Anhydrous (CAS 7772-98-7) serves as a key auxiliary agent in the plastics industry, and its applications center on production support processes, leveraging its reducibility, complexing ability and bleaching properties. The specific use cases are as follows:
Plastic Surface Treatment and Cleaning
Sodium thiosulfate anhydrous has strong reducibility, so it can remove residual oxidants, stains or printing inks from plastic surfaces. For example, in the pre-treatment processes of electroplating and spraying for plastic parts, it neutralizes residual oxidative cleaning agents on the surface and enhances the adhesion of subsequent coatings or platings. It also clears dye residues on plastic surfaces and restores the original color of the substrate.
Impurity Removal and Stabilization in Plastic Production
During the production of some halogen-containing plastics (such as PVC), sodium thiosulfate anhydrous acts as a dechlorinating agent, complexes free chlorine generated in production, prevents chlorine from corroding equipment and avoids chlorine residues that affect the weather resistance and mechanical properties of plastics. In addition, it forms stable complexes with heavy metal ions (such as copper and iron ions), removes heavy metal impurities from plastic raw materials and reduces the adverse effects of impurities on plastic processing performance and finished product color.
Waste Plastic Recycling and Regeneration Processes
In the cleaning and regeneration of waste plastics, sodium thiosulfate anhydrous reduces oxide layers or colored pollutants on the surface of waste plastics, improves the whiteness and purity of recycled plastics. It also complexes metal impurities mixed in the recycling process and enhances the processing stability of recycled plastics.
Notes
Sodium thiosulfate anhydrous does not act as a direct plastic raw material or additive but only applies to auxiliary production and recycling processes.
Control the dosage during use, because excessive use may cause surface residues on plastics or affect the effect of subsequent treatment processes.
