Enhancing Clarity, Thermal Stability, and Long-Term Appearance

Magnesium Aluminum Hydrotalcite (Hydrotalcite), a type of layered double hydroxide (LDH), is widely used as a functional additive in transparent polymer materials. Thanks to its unique layered structure and excellent acid-absorbing capability, it plays a critical role in improving thermal stability, color retention, and optical performance of transparent plastics.

Why Use Hydrotalcite in Transparent Materials?

Transparent polymer applications place extremely high demands on additives. Even a small amount of instability may lead to yellowing, haze, or surface defects. Hydrotalcite is specifically valued for its ability to maintain transparency while enhancing long-term material performance.

Key benefits include:

• Excellent transparency retention

• Low haze and minimal light scattering

• Non-migrating and non-blooming behavior

• Long-term thermal and color stability

Core Functions in Transparent Polymer Systems

Acid Scavenging and Thermal Stabilization

During processing and long-term use, transparent polymers—especially transparent PVC—may release acidic degradation products such as hydrogen chloride (HCl). These acids accelerate polymer degradation and cause discoloration.

Hydrotalcite effectively neutralizes and absorbs acidic substances, interrupting the degradation chain reaction and significantly improving thermal stability.

Performance advantages:

• Delayed yellowing

• Extended thermal stability time

• Improved long-term transparency

Minimal Impact on Optical Properties

Compared with conventional inorganic stabilizers, Hydrotalcite features:

• A refractive index close to that of polymer matrices

• Fine particle size with narrow distribution

• Excellent dispersion within the resin

As a result, it maintains high clarity and low haze even at functional loadings, making it ideal for transparent applications.

Excellent Surface Appearance and Anti-Blooming Performance

In high-clarity products, surface quality is critical. Hydrotalcite exhibits strong structural stability and good compatibility with polymer systems, helping to prevent additive migration, blooming, or surface whitening.

This ensures smooth surfaces, consistent gloss, and long-lasting visual appeal.

Synergistic Effects with Other Stabilizers

Hydrotalcite is commonly used in combination with:

• Organotin stabilizers

• Calcium-zinc stabilizer systems

• Antioxidants and UV stabilizers

Such combinations reduce the overall stabilizer dosage while enhancing both initial and long-term thermal and color stability.

Typical Applications

• Transparent PVC films and sheets

• Medical-grade transparent tubing and hoses

• Food and consumer packaging materials

• Transparent PP, PET, PC, and PMMA components

Hydrotalcite is particularly effective in applications where optical clarity and long-term appearance are critical.

Recommended Properties for Transparent Applications

For optimal performance in transparent materials, Hydrotalcite should feature:

• High whiteness (≥95)

• Sub-micron particle size with narrow distribution

• Low impurity and low iron content

• Excellent dispersibility and compatibility

Conclusion

Magnesium Aluminum Hydrotalcite is a highly efficient functional additive for transparent polymers, offering acid scavenging, thermal stabilization, and long-term transparency retention. It is an ideal solution for manufacturers seeking high optical quality and durable performance in transparent plastic products.