Calcium/Zinc One Pack Heat Stabilizer For PVC Wires&Cables

Mechanism of HCl Scavenging and Long-Term Heat Stability in PVC Cable Insulation

During the high-shear extrusion of PVC cable compounds, thermal stress initiates dehydrochlorination, releasing hydrogen chloride (HCl) that accelerates further degradation. Calcium/zinc stabilizers work through a dual mechanism: zinc soaps rapidly replace labile chlorine atoms to interrupt polyene formation, while calcium soaps act as long-term HCl acceptors, preventing autocatalytic decomposition. The one-pack approach synergistically blends these metal soaps with polyols, phosphites, and lubricants to provide a balanced stabilization package. For white 70°C-rated insulation, initial color retention is a key quality indicator. Our PVC Cable Calcium Zinc Stabilizer is engineered to deliver a brilliant white initial hue that resists yellowing even under extended thermal aging, as validated by JiangSu Uniwel Chemistry Co.,Ltd.'s rigorous oven-aging tests.

Comparing Stabilizer Chemistries for Wire and Cable Applications

By selecting a properly formulated one-pack system like the one offered by JiangSu Uniwel Chemistry, compounders can achieve simultaneous improvement in both color hold and thermal endurance, without the regulatory burden of heavy metals.

Resistance to Vulcanization Pollution, Oils, and Chemicals in Cable Environments

When PVC cables are in contact with rubber insulation or seals, sulfur from cross-linking agents can migrate and react with certain metal stabilizers, forming colored sulfides—a phenomenon known as vulcanization pollution. This leads to unsightly pink or brown staining and can embrittle the PVC jacket. Calcium/zinc stabilizers inherently resist sulfide staining because calcium and zinc sulfides are white or colorless, unlike lead or cadmium sulfides. Our Calcium Zinc One Pack Heat Stabilizer For PVC Cables is specifically formulated to provide robust protection against vulcanization pollution, while also exhibiting excellent resistance to industrial oils, chemical cleaning agents, and plasticizer extraction—common stressors in automotive wiring, appliance cords, and data cables. At JiangSu Uniwel Chemistry Co.,Ltd., we integrate specialty co-stabilizers that reinforce this inertness, ensuring that cable jackets maintain both appearance and mechanical integrity over their service life.

• Eliminates sulfide staining when in contact with rubber insulation
• Retains flexibility and color after immersion in ASTM #2 oil at 70°C
• Resists degradation from commonly encountered cleaning fluids and lubricants

Maximizing Extrusion Output and Surface Quality with Optimized One-Pack Systems

In high-speed wire coating lines, inconsistent stabilizer dispersion can cause melt fracture, die build-up, and fluctuations in wall thickness. A well-designed one-pack stabilizer overcomes these issues by pre-dispersing metal soaps, lubricants, and co-stabilizers into a homogeneous free-flowing powder or granule. At JiangSu Uniwel Chemistry, our Calcium Zinc One Pack Heat Stabilizer For PVC Cables is engineered for rapid, uniform plastification, enabling processors to push line speeds without sacrificing surface smoothness. Its built-in demoulding effect reduces the need for external release agents and minimizes cleaning intervals.

Typical Processing Improvements Achieved

1. Lower melt pressure and torque due to balanced internal-external lubrication.
2. Enhanced dispersion eliminates micro-gels that cause surface imperfections on thin-wall insulation.
3. Consistent feeding behavior from storage to extruder hopper—no segregation during conveying.
4. Reduction in die lip plate-out, extending continuous production runs.

These processing advantages translate directly into higher yield and lower scrap rates, making the one-pack format a cost-effective choice for demanding cable manufacturers.

Regulatory Compliance and the Drive Toward Sustainable PVC Cable Compounds

Global environmental directives such as ROHS (Restriction of Hazardous Substances) and REACH (Registration, Evaluation, Authorisation of Chemicals) have phased out lead and cadmium stabilizers from most consumer and industrial cable markets. Calcium/zinc one-pack stabilizers are inherently free of harmful heavy metals and can fully meet these requirements. Our PVC Cable Calcium Zinc Stabilizer has passed SGS testing against ROHS and REACH SVHC criteria, giving cable producers confidence for export markets. JiangSu Uniwel Chemistry Co.,Ltd. has been at the forefront of this transition: in 2016, we helped formulate China's industry standard GB/T33284-2016, "Specification of Thermostabilizer for Unplasticized Polyvinyl Chloride Profiles". While the standard originated in profiles, the rigorous quality framework informs our entire calcium/zinc product line, ensuring the same level of reliability for cable-grade stabilizers.

By choosing a supplier that actively shapes industry standards and maintains rigorous in-house quality control, cable manufacturers de-risk their supply chain and future-proof their formulations.