LOTSORB UV 329 (CAS:3147 – 75 – 9 )

Product Description 

Lotsorb UV 329 is a UV absorber of the hydroxyphenyl-benzotriazole class used as a light  stabilizer for plastics and other organic substrates. 

Key Features & Benefits 

- Hydroxyphenyl-benzotriazole UVA with excellent spectral coverage in the UV region

- Good photopermanence

- Improves exterior durability of ambient and low temperature cured coatings

CAS number

3147 – 75 – 9 

Chemical Structure 

2phenol, 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3,-tetramethylbutyl)

Molecular weight

329 g/mol 

Properties Typical 

Properties                        

Appearance                        slightly yellow powder  

Melting range                          103 – 105°C 

Flash point                               > 150°C 

Density at 20°C                        1.18 g/ml

Vapor pressure at 25°C            1 E-5 Pa 

Solubility at 20°C (g/100 g solution): 

acetone                                  9 

benzene                                 32 

chloroform                             37

cyclohexane                           15

ethyl acetate                          15

n-hexane                                6 

methanol                               0.6

water                                     < 0.01 

Volatility (TGA, air at 20°C/min) 

Temperature at 1.0% weight loss                 180°C 

Temperature at 2.0% weight loss                 200°C 

Temperature at 5.0% weight loss                 220°C

These typical values should not be interpreted as specifications.

Absorbance Spectrum (in 10 mg/l chloroform)

Lotsorb UV 329 exhibits strong absorbance in the 300 – 400 nm region and minimal absorbance in the  visible region (> 400 nm) of the spectrum. The absorption maxima are at 301 nm and 343 nm (ɛ =  15910 l/mol ∙ cm) in chloroform solution.

Applications 

Lotsorb  UV 329 is an effective light stabilizer for a variety of plastics and other organic substrates. It  protects polymers from UV energy, helping to preserve the original appearance and physical integrity  of molded articles, films, sheets and fibers from outdoor weathering.

Recommend Concentrations

Typical use levels range between 1.0 and 3.0%, depending on the substrate and performance  requirements of the final applications.

Packaging and handling 

Packaging: 20Kg/Carton       

Store the product in a cool, dry, well-ventilated area away from incompatible materials. Unless stated, proper storage will permit usage of the product for 12 months from the manufacture date. For additional handling and toxicological information, consult the Material Safety Data Sheet.