Mass phenols

At room temperature phenol is a white, crystalline mass. Phenol gradually turns pink if it contains impurities or is exposed to heat or light. It has a distinctive sweet, tarry odor, and burning taste. Phenol has limited solubiUty in water between 0 and 65°C. Above 65.3°C phenol and water are miscible in all proportions. It is very soluble in alcohol, ben2ene, chloroform, ether, and partially disassociated organics in general. It is less soluble in paraffinic hydrocarbons. The important physical properties of phenol are Hsted in Table 1. 

Few of the phenol derivatives that have a keto substituent in their side-chain are of interest as fragrance or flavor substances. A number of phenols and phenyl ethers acetylated in the benzene ring have been identified as volatile components of foods. 4-Methoxyacetophenone is of some interest as a fragrance material. 4-Hydroxybenzylacetone, a higher mass phenol ketone, has a characteristic raspberry aroma. 

Properties Crystalline mass phenol-like odor. Wt/ gal 8.67 lb, d 1.039, bp 202C, mp 35.25C, flash p 187F (86C), autoign temp 1038F (558C). Soluble in alcohol, ether, chloroform, and hot water. 

Various HPLC-MS methods were examined to establish the optimal ion source and detector operating conditions for the detection or determination of low molecular mass phenols and flavan-3-ols. Atmospheric pressnre electrospray ionization MS (ESI-MS) in... 

Phenolic degradation products of lignin in Kraft black liquors were extracted with chloroform after acidification and separated by CE with UVD at 214 nm. Simple CZE was insufficient for the separation of low molecular mass phenolic and neutral degradation products of lignin. Enhanced separation was attained on turning to the MEC technique, where the analytes interact with micelles present in the carrier buffer solution . 

Peroxide decomposers, e.g. sulfur-containing compounds, enhance the performance of high molar mass phenols under high temperature service conditions. For example, in polyolefins, dialkyl sulfides (e.g. PS 800) are often used as a peroxide decomposer s)mergists. 

Peroxide Decomposers as Processing Stabiiizers. Alkyl and aryl phosphite esters (see Scheme 12) are effective melt stabilizers. They are often used in combination with hindered phenols (see Table 6). Phosphites generally function by a stoichiometric peroxidolytic mechanism (PD-S) Table 7 illustrates the benefits of using the commercial phosphites TNPP (AO 15) and Irgafos P-EPQ (AO 17, Table 3) for melt stabilization (95). The unique phosphite AO 37 and its phosphate transformation products AOs 38 and 39, (Table 7), which were shown (104,133-135) to operate by a catalytic mechanism (PD-C), are particularly effective at low concentration of the parent stabilizer molecule (see AO 37, Table 7) (95). Phosphites are, however, generally susceptible to hydrolysis. For example, hydrolysis of aryl phosphites leads to the formation of low molecular mass phenol and a... 

Prodanov M, Garrido I, Vacas V, Lebron-Aguilar R, Duenas M, Gomez-Cwdoves C, Bartolome B (2008) Ultrafiltration as alternative purification procedure for the characterization of low and high molecular-mass phenolics from almond skins. Anal Chim Acta 609 241-251... 

Lignin accounts for about 17%-28% of dry weight of grapevines (20% on average in vine shoots [119]). It possesses a three-dimensional amorphous structure resulting from the polymerization of coniferyl, sinapyl, and p-coumaryl alcohol units (Figure 4.9), that is typical of hardwood [120], and its degradation produces low-molecular mass phenolic alcohols, aldehydes, ketones, and acids [121,122], as well... 

Javor, T., Buchberger, W., and Tanzcos, I., Determination of low molecular mass phenolic and non-phenolic bgnin degradation compounds in wood digestion solution by capillary electrophoresis, Microchim. Acta, 135, 45, 2000. 

Spruce wood pyro-vapors Al and Cu (SAR 20) An increase of acetic acid and furans was observed with decrease in higher molecular mass phenols. Adam et al. (2005)... 

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