What is desiccant and anti-gas masterbatch?
In recycled plastics and moisture-sensitive raw materials, water left in the melt turns into steam at processing temperature. The result is holes and fish eyes in film, and silver streaks and internal voids in injection molded parts. Desiccant and anti-gas masterbatch contains high-purity active calcium oxide (CaO), which binds this moisture chemically inside the melt.
How it works
CaO reacts with water to form calcium hydroxide (CaO + H₂O → Ca(OH)₂). Because the water is bound into a solid, stable compound, no steam forms. The calcium hydroxide remains as a fine, inert phase in the polymer; at the right ratio it does not noticeably change the mechanical or optical properties of the product.
For recycling lines
Erk-Han exports this product, together with filler masterbatch, as a core item of its recycling additives range. The moisture in washed and stored PCR/PIR feedstock changes from batch to batch; desiccant masterbatch evens out this variation and helps the line run more steadily. In calcite-filled formulations it also binds the moisture carried in by the filler.
Recommended Dosage
- In standard productions with low moisture content: 1.0% - 2.0%
- In film extrusion (to prevent tearing and fish eyes): 1.5% - 3.0%
- In processing high-moisture and recycled (PCR/PIR) materials: 2.0% - 5.0%
Polymer compatibility
It works best in PE and PP and their recycled grades. In moisture-absorbing, hydrolysis-sensitive polymers such as PET and PA, the masterbatch supports drying but does not replace pre-drying.
Storage
CaO also absorbs moisture from the air. Keep the product in its closed original packaging in a dry place; reseal an opened bag tightly after use and consume it soon.