Among the thermal stabilizers used in PVC processing and production, calcium and zinc stabilizers have the following characteristics relative to other PVC auxiliaries.
1, green environmental protection: no heavy metal elements (lead, separation), can meet the requirements of environmental standards (such as RHOS directive, REACH directive, etc.).
2, low density, can be appropriate to increase the amount of calcium carbonate, reduce the cost: compared with composite lead heat stabilizer, calcium zinc heat stabilizer itself density is about 40% lower, PVC products only switch heat stabilizer meter weight decreased by about 2% on average.
3, improve whiteness, good long-term stability: improve the whiteness of PVC pipe, not easy to yellow, effectively inhibit the chameleon phenomenon of products in summer, excellent long-term stability.
4, vulcanization resistance to pollution: in the field of PVC doors and Windows profiles, the use of composite lead heat stabilizer in some parts of the north of China (the use of large amounts of sulfur-containing coal lead to acid rain) prone to blackening phenomenon, and calcium zinc heat stabilizer will not be polluted.
5, good system switching characteristics: when the traditional compound lead heat stabilizer is converted to organic tin heat stabilizer, there will be cross contamination, resulting in high system switching cost, and calcium zinc heat stabilizer and these two kinds of heat stabilizer will not react, low switching cost.