3,3 -Thiobis

Methylphenol is converted to 6-/ f2 -butyl-2-methylphenol [2219-82-1] by alkylation with isobutylene under aluminum catalysis. A number of phenoHc anti-oxidants used to stabilize mbber and plastics against thermal oxidative degradation are based on this compound. The condensation of 6-/ f2 -butyl-2-methylphenol with formaldehyde yields 4,4 -methylenebis(2-methyl-6-/ f2 butylphenol) [96-65-17, reaction with sulfur dichloride yields 4,4 -thiobis(2-methyl-6-/ f2 butylphenol) [96-66-2] and reaction with methyl acrylate under base catalysis yields the corresponding hydrocinnamate. Transesterification of the hydrocinnamate with triethylene glycol yields triethylene glycol-bis[3-(3-/ f2 -butyl-5-methyl-4-hydroxyphenyl)propionate] [36443-68-2] (39). 2-Methylphenol is also a component of cresyHc acids, blends of phenol, cresols, and xylenols. CresyHc acids are used as solvents in a number of coating appHcations (see Table 3). 

Phenyl sulphides 4,4 -Thiobis-(6-t-butyI-w-cresol) (IX) Very slight Not so powerful as phenylalkanes as a class but synergistic with carbon black. 

Figure lO.U. Oxidation of polyethylene in air at 105°C, Effect of adding 0.1% antioxidant on power factor. A, blank. B, /V,/V -diphenyl-p-phenylenediamine. C, 4,4 -thiobis-(6-butyl-m-cresol). D, Nonox WSP. E, N./V -di-pl-naphthyl-p-phenylenediamine... 

The oxidation reaction proceeds to completion within 30 to 40 min the oxidant consumed is precisely determined on an excess of reagent by means of an iodometric procedure. Polyethylene samples containing varying amounts of 4,4/-thiobis(6-f-butyl-m-cresol) and other synergists were analysed with results close to the expected values. The method has been applied to numerous commercially available polymers. 

The samples investigated initially were commercial high pressure low density, linear low density and high density polyethylenes and had properties given in Table 1. Solutions of these polymers were prepared in concentrations of 0.8 to 3.5 g/1 by dissolving the pol5rmer over a time period of two hours in an oven maintained at 145°C. To avoid degradation 0.05% 4,4 -thiobis(3-methyl-6-tert-butyl phenol) was used as an antioxidant in the solutions. 

Toxieology. 4,4 -Thiobis(6-rrrr-butyl-w-cresol) (TBBC) is of low systemic toxicity in animals allergic contact dermatitis has been reported in humans. 

The 2003 ACGIH threshold limit valuetime-weighted average (TLV-TWA) for 4,4 -thiobis(6-ferr-butyl-7 -cresol) is lOmg/mk... 

An immnotoxicological evaluation of 4,4-thiobis-(6-t-butyl-m-cresol) in female B6C3F1 mice.2. Humoral and cell-mediated immunity, macrophage function, and host resistance. Fundamental and Applied Toxicology,... 

J-tert-Butyl-4-hydroxy-5-methylphenyl sulfide o-Cresol, 4,4 -thiobis[6-tert-butyl- (8), Phenyl, 4,4 -thiobis[2-(1,1-dimethylethyl)-6-methyl- (9),... 

Monsanto Santonox R 4,4 -thiobis (6-tert-butyl-w-cresol)... 

Note Moderately polar solvent, ethereal odor soluble in water and most organic solvents flammable moderately toxic incompatible with strong oxidizers can form potentially explosive peroxides upon long standing in air see the relevant tables in the chapter on laboratory safety commercially, it is often stabilized against peroxidation with 0.5 to 1.0% (mass/mass) p-cresol, 05 to 1.0% (mass/mass) hydroquinone, or 0.01% (mass/mass) 4,4 -thiobis(6-ferf-butyl-m-cresol) can polymerize in the presence of cationic initiators such as Lewis acids or strong proton acids. Synonyms THF, tet-ramethylene oxide, diethylene oxide, 1,4-epoxybutane, oxolane, oxacyclopentane. 

Tris (f-butyl) phenoxy-, 4,4 -methylenebis (2,4- di-f-butyl) phenoxy- or 4,4 -thiobis (2-t-b utyl-6-methyl) phenoxy-radicals have been prepared for ESR observation by oxidation of the corresponding phenolates at a graphite electrode in acetonitrile 561). Dimroth etaL S62 determined reversible le -oxidation potentials for a series of substituted phenols in basic medium. (CF3)2NOH has been oxidized in alkaline medium on platinum or magnetite in quantitative yield to the pink violet hexafluorodimethylnitroxide (CF3)2NO 563 ... 

Thiobis[2-(2-tert-butyl-m-cresol) Phenol, 4,4 -thiobis[2-(1,1 -dimethyl-ethyl)-3-methyl- (4120-97-2), 76, 201, 202... 

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