Cresol INDEX

When some values seem questionable a question mark in brackets is added next to these values. If two very different values are given for one substance the doubtful data source is noted. For instance, for o-cresol, two LD50 values for the rat orally are mentioned as follows LD50 o-r 121 1350 (Merck). This means that the 1350 value that seems high and that applies to a phenol that is particularly corrosive and toxic (see Code du travail (ie Labour Code)) was suggested by the Merck Index. 

In addition to degradation by hydroxyl and nitrate radicals, all three cresol molecules absorb small amounts of W light with wavelengths above 290 nm (Sadtler Index 1960a, 1960b, 1966). Therefore, direct photolysis is also possible however, the photolysis rate is probably slow compared to the reaction with atmospheric radicals. 

Sadtler Index. 1960a. W spectrum for m-cresol (622). Philadelphia Samuel Sadtler and Sons, Inc. 

A pressure glass vessel was charged with a cyclohexane solution of butadiene (60 g) and styrene (15 g) and treated with 11.7 ml of the step 1 product and the mixture polymerized at 50°C for 2.5 hours. The conversion was approximately 100%. Thereafter, 0.5 ml of 5% 2,6-di-f-butyl-p-cresol dissolved in isopropanol was added and the mixture precipitated in an isopropanol solution containing slight amounts of hydrochloric acid and BHT. The mixture was dried and the product isolated having an Mn of 1.74 x 105Da with a polydispersity index (PDI) of 1.02 and MLi+4 (100°C) of 22. 

To improve the solubility of polyimides, Korshak and co-workers used l,l-dichloro-2,2-bis(4-aminophenyl)-ethylene as the starting nucleophile [17] (Scheme 3.2). The resulting polymers turned out to be of relatively high molecular weight (r = 1.2-1.4 dl/g), heat resistant > 270 °C) and fire resistant (oxygen index (OI) = 36-39) (Table 3.2). Polypyromellitimide was soluble in H2SO4 only, but polyimides based on the dianhydrides of benzophenone-3,3, 4,4 -tetracarboxylic acid and diphenyloxide-3,3, 4,4 -tetracarboxylic acid were also soluble in w-cresol and a trichloroethane (TCE)/phenol (3 1) mixture. Diphenyloxide-3,3, 4,4 -tetracarboxylic acid was soluble even in N-methyl-2-pyrrolidone (NMP) (Scheme 3.2). 

NMP N-methyl-2-pyrrolidone MC m-cresol TCP, trichloroethane LOI Limiting oxygen index. ... 

Differential scanning calorimetry Limiting oxygen index w-Cresol... 

In search of less expensive, less toxic, and lower viscosity eluants, a few authors have proposed diluting the active ingredient with a common SEC eluant such as toluene, dichloromethane, or chloroform. To lower the operating temperature and minimize polymer degradation, mixtures of m-cresol with chlorobenzene (50 50, v/v, 43°C), dichloromethane (50 50, room temperature), and chloroform have been used, with 0.25 wt% benzoic acid added to prevent adsorption. In the same vein, o-chlorophenol has been diluted with chloroform (25 75) and used at 20°C. The main disadvantage in this latter solvent was a small dnidc for the polymer, which rendered refractive index measurements difficult. In addition, careful purification of the phenol is required to obtain a detection signal. Dichloroacetic acid diluted to 20 vol% with dichloromethane has been proposed as the mobile phase. However, even at this concentration, PA tends to degrade at room temperature. 

Fluorescence detection at 284/310 nm (extinction/ emission wavelengths) leads to a detection limit of 1.3 mmol/L (0.14 mg/mL for / -cresol). Identification of phenol and /7-cresol may be confirmed by liquid chroma- tography/mass spectrometry. Because HPLC methods require only simple extraction, e.g., by ethyl acetate, and do not require further steps such as derivatization, they j are simple and rapid compared with gas chromatography or gas chromatography/mass spectrometry. Such methods I are useful for monitoring serum phenols in dialyzed patients as an index of hemodialysis adequacy. How- ever, the separation of the three isomers of cresol can only be performed by adding 3-cyclodextrin to the c liquid phase. q... 

CAS Registry Number Index Lists compounds by Chemical Abstracts Service Registry Number. Note there is some redundancy in this index, because many compounds have several Registry Numbers associated with them. Thus the CAS RN in a table entry may differ from the CAS RN that points to it in the index. For example, CAS RN 1319-77-3 in the index points to all three cresol isomers, each of which has its own specific CAS RN. 

Dietz, D., and L. T. Mulligan. 1988a. Subchronic toxicity of para-cresol in Sprague-Dawley rats. Govt. Rep. Announce. Index (U.S.) SS(14), Abstr. No. 836, p. 770 cited in Chem. Abstr CA 110(9) 70771r. 

Figure 2. The refractive index increment (dn/d fif, for solutions of CTA in m-cresol (%) s-tetrachlorelhane (9—) chloroform (w) methylene chloride (-%) and in mixtures of methylene chloride (1) and methanol (3) with q)j = 0.20 (O) 0.25...

Synonyms Acetic acid, 2-methyl phenyl ester Acetic acid, o-tolyl ester o-Acetoxytoluene Acetyl o-cresol o-Cresol acetate o-Cresylic acetate 2-Methylphenyl acetate o-Methylphenyl acetate 2-Methylphenyl ester of acetic acid o-Tolyl acetate Empirical C9H10O2 Formula CH3COOC6H4CH3 Properties Liq. sol. in hot water, org. soivs., oils nearly insol. in cold water m.w. 150.18 dens. 1.05 b.p. 208 C ref. index 1.4998 Precaution Combustible Uses Synthetic flavoring agent in foods and pharmaceuticals cosmetics ingred. 

Synonyms Acetic acid-4-methylphenyl ester 4-Acetoxytoluene p-Acetoxytoluene Acetyl p-cresol p-Cresol acetate p-Cresylic acetate 4-Methylbenzoic acid methyl ester 4-Methyl phenyl acetate p-Methylphenyl acetate Paracresyl acetate p-Tolyl acetate p-Tolyl ethanoate Classification Aromatic ester Empirical C9H10O2 Formula CH3CO2C6H4CH3 Properties Colorless liq., anise sweet fragrant odor sol. in fixed oils, propylene glycol misc. with alcohol, ether insol. in water, glycerin m.w. 150.18 dens. 1.047 b.p. 210-211 C dec. 360 C flash pt. 90 C ref. index 1.5010 Toxicology LD50 (oral, rat) 1900 mg/kg, (skin, rabbit) 2100 mg/kg mod. toxic by ing. and skin contact irritant TSCA listed Precaution Combustible Hazardous Decomp. Prods. Heated to decomp.. 

Definition Ester of p-cresol and isobutyric acid Empirical C11H14O2 Formula CH3C6H40C0CH(CH3)2 Properties Colorless liq., lily-narcissus odor sol. in alcohol insol. in water m.w. 178.23 dens. 0.993 b.p. 237 C flash pt. >100 C ref. index 1.485-1.489... 

Dark (4) found agreement between the SEC measurements of various nylons dissolved in /w-cresol at 100°C with detection by differential refractive index and TFA-nylon in chloroform at room temperature with UV detector. The various nylons included nylon 6, 11, 6, 6, 6, 9, 6, 10, and 6, 12. The better reproducibility of weight-average MW of TFA-nylon (3-4%) than nylons in m-cresol (7-9%) was also reported. 

Other Names Bromocresol green Phenol, 4,4 -(3H-2,l-benzoxathiol-3-yUdene)fcM[2,6-dibromo-3-methyl-, S,S-dioxide m-Cresol, 4,4 -(3H-2,l-benzoxathiol-3-ylidene)fcw[2,6-dibiomo-, S,S-dioxide o-Toluenesulfonic acid, a,a-fci5 (3,5-dibromo-4-hydroxy-(3-tolyl)-a- hydroxy-, y-sultone 3H-2,l-Benzoxathiole, phenol deriv. 3, 3",5, 5"-Tetrabromo-m-cresolsulfonephthalem BCG Bromcresol green NSC 7817 Tetrabromo-m-cresolphthalein sulfone CA Index Name Phenol, 4,4 -(l,l-dioxido-3H-2,l-benzoxathiol-3-ylidene)to[2,6-dihromo-3-methyl-CAS Registry Number 76-60-8 Merck Index Number 1386 Chemical Structure... 

The enzymatic reaction kinetics on the HRP-catalyzed oxidation of p-cresol in aqueous 1,4-dioxane or methanol showed that the cataljdic turnover niunber and Michaelis constant were larger than those in water (235). Numerical and Monte Carlo simulations of the peroxidase-catalyzed polymerization of phenols were demonstrated (236). The simulations predicted the monomer reactivity and polymer molecular weight, leading to synthesis of polymers with specific molecular weight and index. In an aqueous 1,4-dioxane, the formation of monomer aggregate was observed (237), which might elucidate the specific polymerization behaviors in such a medium. 

There are only a few one-compcment solvents of nylons, e. g. the univosal solvent of all nylons — cresol, or some fluminated alcohols. Multiconqxmmt solvents are the ones mostly used in the study of soluticm properties, mainly in the determination of the molecular parameters of nylons. The main reason for this is the specific demands of various methods on the refractive index, viscoaty, density, boiling point and other properties, which are difficult to meet by means thermodynamic quality of the solvent (See 3.2). 

Preliminary results show that for a more accurate determination of of nylon digomeB, tems with extremely hi re active index increments (>0.5 nd/g, e. g. in the mixture m-cresol/n-heptane) may ove helpful (See Chapter 6). 

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