Octabenzone

Description

Octabenzone is a UV absorber/screener. It is used to protect polymers (e.g., polyethylene, polypropylene, polyvinylchloride) against damage by UV light. Colorless crystals; Light yellow powder.
Stable under recommended storage conditions.

Characterization

UV Absorber 531 is an ultraviolet light absorber (UVA) of the benzophenone class, imparting good light stability when used in combination with a hindered amine light stabilizer (HALS) of the Chimassorb, Tinuvin® or Uvinul® range. It shows good compatibility with polyolefins and plasticized PVC.

Applications

The main application of UV Absorber 531 is in combination with a HALS the
light stabilization of low density and linear low density polyethylene as well
as ethylene-vinyl acetate copolymers for agricultural films. It can be used as
well as a UV barrier to protect the contents of packages for both industrial
and consumer applications. Also, in combination with HALS, UV Absorber 531
can be used in high density polyethylene molded articles, e. g. in crates.
UV Absorber 531 also protects a number of other polymers against degradation
caused by light exposure such as plasticized PVC and rubbers.
UV Absorber 531 can be used in combination with antioxidants, phosphites
and other light stabilizers.

Physical properties

Uses

Adsorbents and absorbents;
Paint additives and coating additives not described by other categories
Processing aids, not otherwise listed
Air Care Products
Building/Construction Materials not covered elsewhere
Fabric, Textile, and Leather Products not covered elsewhere
Furniture and Furnishings not covered elsewhere
Paints and Coatings
Plastic and Rubber Products not covered elsewhere

Features/benefits

UV Absorber 531 is particularly suitable for thick films, typically > 100 μm and thick sections. The low vapor pressure of UV Absorber 531 prevents losses during processing. Low migration rates reduce the risk of blooming.

Analytic Laboratory Methods

Migration of photo stabilizers from plastics was studied in model elution expt where the plastics were placed at different temp 20 and 45 degree in different solvents, e.g. H2O, acetic acid,  sunflower oil, heptane, and the amt of photostabilizer eluted was determined by spectrophotometry and by gas chromatography. The elution of 2-hydroxy-4-n-octyloxybenzophenone depended on the type of plastic. Elution was low in polystyrene and high in polyolefins, polyethylene. Food contamination from these plastic additives is discussed.

Guidelines for use

Handling & Safety

In accordance with good industrial practice, handle with care and avoid
unnecessary personal contact. Avoid continuous or repetitive breathing of
dust. Use only with adequate ventilation. Protect skin. Avoid dust formation
and ignition sources.
For more detailed information please refer to the material safety data sheet.

References

1. https://pubchem.ncbi.nlm.nih.gov/compound/Octabenzone#section=U-S-Exports
2. https://en.wikipedia.org/wiki/Octabenzone

Description

Octabenzone appears as light yellow/yellowish crystals/fine powder and is odourless and freely soluble in benzene, n-hexane, and acetone; slightly soluble in ethanol; and very slightly soluble in ethane dichloride. Octabenzone is a light stabiliser with good performance, capable of absorbing the UV radiation of 240–340 nm wavelength with the characteristics of light colour, non-toxicity, good compatibility, small mobility, easy processing, etc. Octabenzone protects the polymer to its maximum extent and helps to reduce its colour. It can also delay the yellowing and impede the loss of its physical function. Industrial applications of octabenzone is very extensive and applied to PE, PVC, PP, PS, PC, organic glass, polypropylene fibre, ethylene-vinyl acetate, etc. Also, octabenzone has very good light-stability effect on drying phenol aldehyde, varnish of alcohol and acname, polyurethane, acrylate, expoxnamee, etc. The major uses include UV stabiliser, for example, polyethylene and polypropylene fibres.

Chemical Properties

Light yellow powder

Uses

HOBPs are UV absorbers for insulating plastics, which can be incorporated with active layers to increase the stabilization of organic solar cells (OSCs). It may be incorporated in parylene C films to enhance the light stability, which can be potentially used as a moisture transfer membrane for electronic boards and photovoltaics.

Uses

To stabilize polyethylene against deterioration by ultraviolet light.

Preparation

Preparation by reaction of n-octyl chloride with 2,4-di-hydroxybenzophenone,
in the presence of a mixture of sodium carbonate, triethylamine and potassium iodide in refluxing butanol for 15 h (90%); 
in the presence of potassium carbonate in cyclohexanone at 145° for 5 h (66%);
in the presence of potassium hydroxide and antimony triiodide in diethylene glycol at 150° for 1 h (93%);
in the presence of sodium bicarbonate and potassium iodide in 1-methylpyrrolidone for 2 h at 150° (96%).

Definition

ChEBI: Octabenzone is a member of benzophenones.

General Description

2-Hydroxy-4-(octyloxy)benzophenone (HOBP) is a UV based absorber that has 2-hydroxybenzophenone as a functional group. It can be used to enhance the light fastness of polymers using UV absorbers with sulfur and phosphorus compounds.

Flammability and Explosibility

Not classified