Qihong: Three Types of Stabilizers for Processing PVC Products, There Must Be One Suitable for You!

    For the selection of stabilizers in processing PVC low-foaming products, the stabilizers commonly used in processing PVC low-foaming dry blends include:

(1) Lead salt stabilizers;    (2) Organotin stabilizers;    (3) Metallic soap stabilizers.

Stabilizers can be selected according to the product, processing equipment and application range. Priority should be given to stabilizers that provide good processing performance, excellent weather resistance and harmlessness to the human body. Qihong Calcium-Zinc Stabilizer GX400: a new generation of environmentally friendly product with non-toxic and high-efficiency characteristics, the first choice for export products.

    Currently, lead-based stabilizers account for a major proportion due to their low cost, ease of processing, and wide application range, suitable for profiles, sheets, pipes, and films. Qihong Composite Lead Salt Stabilizer QY298: contains 33% lead, is inexpensive, and offers excellent thermal stability and electrical properties.

    When temperature stability and transparency requirements are strict, organotin stabilizers are used. Organotin Stabilizer YJ-906: highly suitable for transparent PVC products, with extremely high thermal stability and excellent initial coloring performance, pure color, minimal gas release, and no precipitation. It exhibits excellent high-temperature color stability and long-term dynamic stability.

    When formulating recipes, it should be noted that different stabilizer systems, in addition to their actual stabilizing effects, also have activating effects on foaming agents. Other substances also have stabilizing effects but are only used for self-stabilization, so they are respectively called co-stabilizers, chelating agents, ultraviolet absorbers, and antioxidants.

    The main representatives of these stabilizers are epoxy compounds, which can be high-molecular-weight or low-molecular-weight compounds. A typical representative harmless to human health is epoxidized soybean oil. Since almost all stabilizers contain metals, epoxy compounds act synergistically with them to improve light stability. In addition, epoxy compounds are also used as processing aids to enhance surface smoothness. Alkyl and nitrile phosphites are used as chelating agents, which can reduce the activity of metal oxides generated by HCl elimination, thereby improving photothermal stability.

    Ultraviolet absorbers can convert high-energy ultraviolet rays harmful to PVC into heat, thereby improving the light stability of products. Phenols and organic sulfides are mainly used as antioxidants; they alleviate the thermal oxidative decomposition of PVC by absorbing free radicals generated by oxidation.