tert-Butyl peroxybenzoate

Description

Tert-Butyl peroxybenzoate (TBPB) is an organic compound with the formula C6H5CO3CMe3 (Me = CH3). TBPB, a pale yellow, is exclusively encountered as a solution in solvents such as ethanol or phthalate. It is an ester of peroxybenzoic acid and the most widely produced perester.

Chemical Properties

colourless or slightly yellow liquid. At 124 ℃ (temperature), the half-life of tert-butyl peroxybenzoate is 10 hours.

Uses

Tert-Butyl peroxybenzoate is used for elevated temperature curing of polyesters and to initiate polymerization reactions. It could used as a Polymerization initiator for polyethylene, polystyrene, polyacrylates, and polyesters. It is also used as a chemical intermediate.

Uses

tert-Butyl peroxybenzoate was employed as polymerization and cross-linking catalyst. It was also was employed as initiator during grafting of 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO)-4-oxyacetamido-(3 propyltriethoxysilane) to poly(ethylene co-octene and in preparation of conformal poly(cyclohexyl methacrylate) thin films via initiated chemical vapor deposition.

Synthesis Reference(s)

Journal of the American Chemical Society, 68, p. 642, 1946 DOI: 10.1021/ja01208a033

General Description

Clear, colorless to slightly yellow liquid with a mild, aromatic odor. tert-Butyl peroxybenzoate also is stored and transported as a mixture with inert solids and as a solvent slurry, to mitigate the explosion hazard.

Air & Water Reactions

Insoluble in water.

Reactivity Profile

TERT-BUTYL PEROXYBENZOATE explodes with great violence when rapidly heated to a critical temperature; pure form is shock sensitive and detonable [Bretherick 1979 p. 602]. Upon contact with organic matter, t-butyl peroxybenzoate can ignite or give rise to an explosion [Haz. Chem. Data 1973 p. 77].

Hazard

Oxidizing material; do not store near com- bustible materials.

Health Hazard

t-Butyl peroxybenzoate is a mild skin andeye irritant. Exposure to 500 mg/day causedmild irritation in rabbit eyes and skin. Toxicitydata on animals show a low order oftoxicity.
LD₅₀ value, oral (mice): 914 mg/kg
It has been reported to cause tumors(blood) in mice. Its carcinogenic actions onhumans are unknown.

Fire Hazard

Highly reactive and oxidizing compound with moderate flammability; flash point (open cup) 107–110°C (224.6–230°F); autoignition temperature not reported.
It forms an explosive mixture with air; the explosive range not reported. It is not sensitive to shock but is heat sensitive. It explodes on heating; self-accelerating decomposition temperature 60°C (140°F).
It may react explosively when mixed with readily oxidizable, organic, and flammable substances. Fire-extinguishing agent: water from a sprinkler; use water to keep the containers cool.

Flammability and Explosibility

Flammable

Safety Profile

Moderately toxic by ingestion. A skin and eye irritant. Questionable carcinogen with experimental tumorigenic data. Mutation data reported. See also PEROXIDES, ORGANIC. Potentially explosive when heated above 11 5'C. Explosive reaction on contact with organic matter or copperQ) bromide + limonene. When heated to decomposition it emits acrid smoke and fumes.

Carcinogenicity

Other studies have determined the possibility that t-butyl peroxybenzoate can be metabolized to free radicals by human carcinoma skin keratinocytes. Free radicals are suggested to be involved in the cascade of events occurring during tumor promotion .

storage

It should be stored in a well-ventilatedplace at a temperature between 10 and27°C (50–80°F), isolated from oxidizable,flammable, organic materials and accelerators.It should be shipped in glass, polyethylene,and earthenware containers of up to5-gallon capacity placed inside wooden orfiberboard boxes.