UV Absorber 329

UV Absorber 329 is a high-performance and highly effective anti-aging additive. It is soluble in benzene, styrene, and ethyl acetate, slightly soluble in ethanol, and insoluble in water. It can absorb ultraviolet light of 270–340 nm and is widely used in PE, PVC, PP, PS, PC, polypropylene fiber, ABS resin, epoxy resin, resin fiber, and ethylene-vinyl acetate (EVA), etc. It can also be used in packaging materials such as plastic containers and food packaging boxes, providing them with good light stabilization. Recommended dosage: 0.1%–0.5%; for thick articles, 0.05%–0.2%.
 
Solubility of UV Absorber UV-329 (grams dissolved per 100 ml solvent at 20 °C): Water: <0.01; Acetone: 9; Benzene: 32; Chloroform: 37; Methanol: 0.6; Dichloromethane: 38; Cyclohexane: 15; Ethyl acetate: 15; n-Hexane: 6
 
Reference dosage: PC (0.1–1.0%), PVC (0.25–1.0%), ABS (0.25–0.75%), MMA (0.1–1.0%)
 
Reference quality standard: Appearance: white powder; Content: ≥99%; Volatile matter: ≤0.5%; Melting point: 101–106 °C; Ash content: ≤0.05%; Light transmittance: 440 nm ≥97%, 500 nm ≥98%
 
Common UV absorbers
Phenyl salicylate (composition: phenyl o-hydroxybenzoate), UV Absorber UV-P (composition: reaction product of o-nitroaniline and p-cresol), UV Absorber UV-O (composition: 2,4-dihydroxybenzophenone), UV Absorber UV-9 (composition: 2-hydroxy-4-methoxybenzophenone), UV Absorber UV-531 (composition: 2-hydroxy-4-n-octyloxybenzophenone), UV Absorber UVP-327 (composition: 2-(2′-hydroxy-3′,5′-di-tert-butylphenyl)-5-chlorobenzotriazole), UV Absorber RMB (composition: resorcinol monobenzoate), Light Stabilizer AM-101 (composition: 2,2′-thiobis(4-tert-octylphenoxy) nickel), Light Stabilizer GW-540 (composition: tris(1,2,2,6,6-pentamethylpiperidyl) phosphite), Light Stabilizer 744 (composition: 4-benzoyloxy-2,2,6,6-tetramethylpiperidine), Light Stabilizer HPT (composition: hexamethylphosphoric triamide)
 
Inorganic UV absorbers
Light stabilizers used historically can be roughly divided into four categories: UV absorbers, quenchers, free-radical scavengers, and light screens. In terms of mechanism, they mainly work in three directions. First, blocking UV radiation from entering the product — keeping the enemy outside the gate — but screens are non-selective in blocking light, resulting in opaque products. Second, capturing the free radicals triggered by UV entering the polymer, preventing them from further causing other molecular scissions; essentially, this protects the overall integrity of the product at the cost of very few molecular bond breaks. When using UV-sensitive colorants, fading is prone to occur. Third, absorbing UV energy and dissipating it as heat, which is a very good method. With the growing international concept of green consumption, products are required to have a longer service life to protect limited resources. The toxicity of products has also attracted more attention. Against this background, inorganic nano UV absorbers emerged. Nanomaterials refer to materials whose size has at least one dimension between 1 and 100 nm. Currently, the powders used as UV absorbers are basically spherical particles whose diameter is comparable to the UV wavelength; UV light waves undergo strong reflection on the particle surface, a phenomenon called the small-size effect of nanomaterials. Under the small-size effect, nanomaterials can strongly shield UV radiation, while visible-light wavelengths are much larger than the particle size, so they undergo diffraction and pass through the particles, giving nanomaterials high visible-light transmittance while shielding UV. In summary,

Inorganic UV absorbers have the following outstanding advantages:
1. High UV shielding efficiency and good visible-light transmittance.
2. Excellent stability, enabling long-term function, maintaining the bright appearance of polymer products for a long time, and extending their service life.
3. Currently developed products are essentially non-toxic and have a wide range of applications.
4. When particles reach the nanometer scale, their mechanical, optical, electrical, and magnetic properties change greatly, which brings optimization of the mechanical properties of polymer materials, making it possible to manufacture functional materials. High-strength plastics have already been produced using nanomaterials, and antibacterial and self-cleaning functional coatings have been manufactured by exploiting the high surface activity of nanomaterials.
 
 
Chemical properties: Off-white powder