If you manufacture outdoor furniture, agricultural films, automotive parts, or any plastic product that sees sunlight, UV degradation is your #1 enemy. Yellowing, cracking, chalking, and mechanical failure — all caused by UV radiation.
Indian conditions make it worse: high UV intensity, 45°C+ temperatures, and monsoon humidity create the perfect storm.
Here's how to fight it.
How UV Destroys Plastics
The destruction follows a predictable path:
- UV absorption → free radical formation in the polymer
- Chain scission → molecular weight drops → material becomes brittle
- Oxidation → carbonyl groups form → yellowing
- Surface erosion → chalking, cracking, eventual failure
The key insight: you need to interrupt this chain at multiple points.
The Two-Layer Defense
The most effective protection uses both UV absorbers and HALS together:
Layer 1: UV Absorbers (The Sunscreen)
These absorb UV radiation before it can damage the polymer.
| Product | CAS | Best For | Dosage | Price |
|---|---|---|---|---|
| UV-531 | 1843-05-6 | General purpose | 0.2-0.5% | ₹800-1,200/kg |
| UV-P | 2440-22-4 | Clear products | 0.2-0.5% | ₹1,000-1,500/kg |
| UV-1577 | 147315-50-2 | High performance | 0.1-0.3% | ₹2,000-3,000/kg |
Layer 2: HALS (The Bodyguard)
Hindered Amine Light Stabilizers scavenge free radicals. The magic: they're regenerative — they don't get consumed, providing years of protection.
| Product | CAS | Best For | Dosage | Price |
|---|---|---|---|---|
| Tinuvin 770 | 52829-07-9 | General HALS | 0.1-0.5% | ₹2,000-4,000/kg |
| Chimassorb 944 | 71878-19-8 | High MW HALS | 0.1-0.3% | ₹3,000-5,000/kg |
| Tinuvin 622 | 65447-77-0 | Polymeric HALS | 0.1-0.5% | ₹2,500-4,000/kg |