Chiguard^®: UV Stabilizers

Ultraviolet (UV) radiation from sunlight gradually breaks down and damages polymers over time—a common issue seen in plastic components, coatings, and textiles. UV stabilizers help prevent UV-induced degradation and significantly extend product lifespan under sunlight exposure.

◆The Role of UV Stabilizers

UV stabilizers are essential additives designed to protect polymers from UV-induced deterioration. They effectively reduce material breakdown and discoloration, helping preserve the appearance and performance of outdoor products.

◆Types of UV Stabilizers

UV absorbers and stabilizers act as an invisible shield, quietly protecting plastic products from damage caused by sunlight, oxygen, and heat.

• Outdoor chairs: Easily degraded after one year of sun exposure.
• Automotive parts: Lose gloss and become brittle.
• Food packaging: Degraded by heat, compromising safety.

Although both UV absorbers and UV stabilizers protect materials, they function through different mechanisms.

UV Absorbers (UVA) –

When materials are exposed to sunlight for extended periods, UV radiation damages molecular structures, leading to yellowing, aging, and brittleness. UV absorbers act like sunscreen for materials — absorbing UV radiation and converting it into harmless heat. This prevents the formation of reactive chemical energy and protects the internal structure of the polymer. They are especially important for preserving transparency and long-term aesthetics.

Common UV absorbers include benzophenones, benzotriazoles, and triazines.

How it works:

UV absorbers do not block UV rays directly; instead, they absorb high-energy light and convert it to heat. This mechanism slows down material degradation, ensuring long-term performance even under harsh UV and high-temperature conditions.

Hindered Amine Light Stabilizers (HALS) –

Compared to UV absorbers, UV stabilizers work more like "internal maintenance" for materials. They combat internal damage caused by UV radiation, oxygen, and heat. Their core function is to eliminate free radicals generated after UV exposure—these radicals trigger chain reactions that cause oxidation and degradation within polymers.
HALS are highly effective even at low concentrations. They neutralize free radicals, break degradation chains, and help delay aging and prevent brittleness or performance loss.

How it works:

UV exposure produces free radicals within the material, accelerating aging and embrittlement. HALS quickly capture these radicals and convert them into stable, non-destructive molecules, effectively preventing further damage and extending the material's lifespan and appearance.

◆ How UVA and HALS Work Together to Extend Material Life

UVA and HALS each provide distinct protective mechanisms and are often used together synergistically to deliver comprehensive inside-out protection. This dual-action strategy is the foundation of the Chiguard® stabilizer system.

UVA (UV Absorbers) absorb UV energy and convert it into harmless heat, preventing molecular damage caused by high-energy radiation. They are ideal for applications requiring optical clarity, such as optical films, transparent packaging, and coatings.
HALS (Hindered Amine Light Stabilizers) eliminate free radicals formed by UV exposure, suppressing internal degradation reactions and preserving the material's structural integrity. They effectively extend product life and prevent brittleness and discoloration.

🛡️ Synergistic Effect of UV Absorbers and Stabilizers:

UVA: Absorbs and converts UV energy, reducing surface-level damage
HALS: Neutralizes free radicals, repairs internal damage, and prevents material deterioration.

This dual protection strategy enhances both durability and aesthetics, making it an essential solution for high-performance plastics and coatings.

Application Example:

Outdoor furniture:
1. UVA – Absorbs UV and converts it to heat, delaying yellowing and surface degradation.
2. HALS – Repairs internal free radical damage, maintaining durability and flexibility.
👉 Together, UVA + HALS act as a double shield that keeps materials long-lasting and resistant to environmental wear.

◆Key Applications

Plastics – Outdoor furniture, accessories, and components
Coatings – Automotive and industrial surfaces
Adhesives and Sealants
Textiles – Awnings, outdoor fabrics, and apparel

◆Impact on Product Lifespan

Properly formulated UV stabilizer systems significantly enhance product durability, slow down degradation, and help maintain long-term appearance and performance—meeting growing market demands for high-weatherability products.