4,4 - bisphenol

Bisphenol A is made by reacting phenol with acetone in the presence of an acid catalyst (Fig. 1). The temperature of the reaction is maintained at 50°C (120°F) for about 8 to 12 hours. A slurry of bisphenol A is formed, which is neutralized and distilled to remove excess phenol. 

Bisphenol A is used in the production of epoxy resins and polycarbonate resins. 

Bisphenol-A (BPA) is an important raw material for the synthesis of polycarbonates, epoxy resins and other polymers as well as polymer additives. It is conventionally produced by acid-catalysed condensation of phenol with acetone. Application of various catalysts for the BPA synthesis is discussed with particular attention to the substrates conversion and the reaction selectivity. Recent developments in the BPA production and its applications are presented. Moreover, potential toxicological and endocrine disrupting properties of BPA are considered with the emphasis on human exposure, general toxicology, and biological effects. 

Keywords 4,4 -Isopropylidenediphenol, Bisphenol-A, synthesis, catalysts, applications, epoxy resins, polycarbonates, polysulphone, polyetherimide, flame retardants, human health, environmental safety 

Apart from the lUPAC name 4,4 -(propan-2-ylidene)diphenol, there are many synonyms for Bisphenol-A [1], such as, 4,4 -isopropylidenediphenol, 2,2-bis(4-hydroxyphenyl)propane, 2,2-di(4-phenylol)propane, bis(4-hydroxyphenyl)dimethylmethane, p,p -dihydroxydiphenylpropane, p,p -isopropylidenebisphenol, beta-di-p-hydroxyphenylpropane, DIAN, diano, Bisferol A, Parabis A, Rikabanol or Ucar Bisphenol-A, in common usage in different countries. 

Sabu Thomas and Visakh P.M. (eds.) Handbook of Engineering and Specialty Thermoplastics, (221-270) Scrivener Publishing LLC 

No applications or uses for BPA were proposed until the late 1910s. At that time, the first patent on an improved method of the BPA synthesis and its application for production of artihcial gum was obtained by Wallace Appleton Beatty in 1917 [5]. The first industrial application of BPA was the production of synthetic shellac, named Albertol, which was originally started by German company Chemische Fabriken Dr. Kurt Albert in 1923 [6,7]. 

Bisphenol A is used as an intermediate in the production of epoxy resins which are used in the internal coating for food and beverage cans to protect the food from direct contact with metal. It can migrate from cans with epoxy coating into foods, especially at elevated temperatures (24,25). 

In samples of canned drink products, the amount of bisphenol A was measured. Due to the particular sensitivity of the analytical method, bisphenol A was detected in samples of almost all drink products except for two tonic water soda products and one energy drink product. It is believed that quinine hydrochloride, which is commonly used as a bittering agent in tonic type drinks, may interfere with the extraction method in the analytical procedure. 

The concentrations of bisphenol A in most of the drink products were generally low. 75% of the products had bisphenol A levels of less than 0.5 85% had levels less than 1 jUgT. The average 

Bisphenol-A is produced at 500°C by the eorrderrsation of acetone with phenol in the presence of an acid catalyst. In early proeesses sirlfuric acid or dry hydrochloric acid was promoted with methyl mercaptarrs. More recently acid ion exchange resins have been used  

In terms of quantity, other polymer building blocks, such as bisphenol A and caprolactam are also among the most important phenol products. 

Bisphenol A was first obtained by Alexander P.Dianin in 1891, by acid catalysed condensation of phenol and acetone. 

In some European countries, the compound was named Dian, after its Russian discoverer. As a cost-effective bifunctional phenol, bisphenol A is particularly suited for the production of resins, as a result of its high reactivity and bifunctionality. Bisphenol A is complemented by other bisphenols such as bisphenol F and bisphenol S in the production of resins. 

1 Reactor 2 Hydrochloric acid column 3 Hydrochloric acid separator, 4 HCl recovery 5 Phenol column 6 Isomers column 7 Bisphenol A column 8 Bisphenol A crystallizer 9 Solvent tank 10 Solvent recovery 

A satisfactory yield can also be obtained in the production of bisphenol A by the reaction of phenol with methylacetylene on ion-exchange resins. However, this method has not yet been applied, because of the high price of methylacetylene. Other methods which have no industrial use at present include the reaction of p-isopropenylphenol with phenol in the presence of Friedel-Crafts catalysts which, at low temperature, gives almost quantitative yields of bisphenol A. 

Semiconductors thermoelectric cooling power generation application for commercial use, Bi2Te3 is doped with selenium sulfide to alter its conductivity. 

Toxicology. Bismuth telluride, either alone or doped with selenium sulfide, is apparently of very low toxicity. 

In limited industrial experimental work with bismuth telluride under controlled conditions (vacuum hoods), no adverse health effects were encountered other than tellurium breath.  

In a similar 11-month study in which animals were exposed to undoped bismuth telluride dust of 0.04-p,m diameter at 15mg/m no adverse responses of any type were observed other than the pulmonary responses to the inhalation of an inert dust. 

The 2003 ACGIH threshold limit valuetime-weighted average (TLV-TWA) is 10 mg/ m for undoped and 5mg/m for doped bismuth telluride. 

4-Fluoro-4 -hydroxydiphenyl sulfone, and (fluorophenyl)-(trifluorophenyl) sulfone as initiator 10 

5-[(4-fluorophenyl)sulfonyl]-2-fluorobenzoic acid and bis-(4-hydroxyphenyl)-sulfone 12 

Oxidative dimerization of 2,6-di-tert-butyl phenol to 3,3 5,5 -tetra- er butyl biphenol (TBBPL) and subsequent debut-ylation. 

In the first two methods, severe reaction conditions are required. Problems arise by the need of separation of large amounts of inorganic salts used. For this reason, the oxidative dimerization of 2,6-di-tm-butyl phenol is most preferably used to prepare BP on an industrial level. 

The debutylation rates of the four butyl groups in TBBPL are not equal, and that the rate slows as the number of butyl groups decreases. Therefore, continuous debutylation of TBBPL using a cascade of reactors can produce BP with a high yield and high purity continuously on an industrial level. For the debutylation reaction of TBBPL, an acid catalyst, such as p-toluenesulfonic acid is used at a reaction temperature up to 250°C.  

Polycarbonate baby bottle. [Dani Carclona/Reuters.] 

Chromatography is the most powerful tool in an analytical chemist s arsenal for separating and measuring components of a complex mixture. With mass spectromet-ric detection, we can identify the components as well. This chapter discusses principles of chromatography and mass spectrometry, and the following chapters take up gas and liquid chromatography. 

Column packing (stationary phase). suspended in solvent (mobile phase) 

Chromatography is widely used for Quantitative analysis How much of a component is present  

Polish botanist M. Tswett invented chromatography in 1903 to separate plant pigments with a column containing solid CaCOj particles (the stationary phase) washed by hydrocarbon solvent (the mobile phase). Separation of colored bands led to the name chromatography, from the Greek chromatos ( color ) and gra-phein ( to write O— color writing.  

Spectrometer Inletsystem Source Temperature Electron Energy Scan Range 

Physical Characteristics - Slightly yellow flakes, rap 48 - 55 C, bp 264 - 270 C (733 ram Hg). - Soluble in most organic solvents. 

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Figure C2.1.17. Stress-strain curve measured from plane-strain compression of bisphenol-A polycarbonate at 25 ° C. The sample was loaded to a maximum strain and then rapidly unloaded. After unloading, most of the defonnation remains.

Polycarbonate is a polyester in which dihydric (or polyhydric) phenols are joined through carbonate linkages. The general-purpose type of polycarbonate is based on 2,2-bis(4 -hydroxybenzene)propane (bisphenol A) and has the general structure ... 

DGEBA. See Bisphenol A, diglycidyl ether. Bisphenol A, diglycidyl ether (DGEBA) [1675-54-3]... 

Fig. 23. Representative protecting groups for phenolic and carboxylic acid-based systems, (a) The polymer-based protecting groups are fisted in order of increasing activation energy for acid-catalyzed deprotection, (b) Acid-labile monomeric dissolution inhibitors, a bifunctional system based on protected bisphenol A. (c) Another system that combines the function of dissolution inhibitor and PAG in a single unit.

The para and ortho positions of phenols condense at the carbonyl group of acetone to make bisphenols, eg, bisphenol A, 4,4 -(l-methylethyhdene)bisphenol [80-05-07]). If the H atom is activated, CICH— compounds add to the carbonyl group in the presence of strong base chloroform gives chloretone (l,l,l-trichloro-2-methyl-2-propanol [57-15-8]). 

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