Bisphenol-A yield

Nucleophilic attack by the triphenylphosphine opens the epoxide, producing a betaine, 1. Proton abstraction from bisphenol A yields the phenoxide anion, 2. The phenoxide reacts with the electrophilic carbon attached to the positive phosphorus, 3, regenerating the catalyst. When the phenol is exhausted, the betaine can decompose into a terminal olefin and triphenylphosphine oxide (the final step in the Wittig... 

Proton abstraction from bisphenol A yields the phenoxide anion, forming a phosphonium salt. The phenoxide reacts with the electrophilic carbon attached to the positive phosphorus regenerating the catalyst ... 

The yield of hydroquinone based on bisphenol A is close to 90%. The phenol and the acetone formed can easily be recycled. However, this process has not been industrialized. 

The most important commercial chemical reactions of phenol are condensation reactions. The condensation reaction between phenol and formaldehyde yields phenoHc resins whereas the condensation of phenol and acetone yields bisphenol A (2,2-bis-(4-hydroxyphenol)propane). PhenoHc resins and bisphenol A [80-05-7] account for more than two-thirds of U.S. phenol consumption (1). 

Benzene is alkylated with propylene to yield cumene (qv). Cumene is catalytically oxidized in the presence of air to cumene hydroperoxide, which is decomposed into phenol and acetone (qv). Phenol is used to manufacture caprolactam (nylon) and phenoHc resins such as bisphenol A. Approximately 22% of benzene produced in 1988 was used to manufacture cumene. 

Advancement Process. In the advancement process, sometimes referred to as the fusion method, Hquid epoxy resin (cmde diglycidyl ether of bisphenol A) is chain-extended with bisphenol A in the presence of a catalyst to yield higher polymerized products. The advancement reaction is conducted at elevated temperatures (175—200°C) and is monitored for epoxy value and viscosity specifications. The finished product is isolated by cooling and cmshing or flaking the molten resin or by allowing it to soHdify in containers. 

A different variety of copolymer has been prepared by Gramain and Frere who treated 1,10-diaza-l 8-crown-6 with the bisglycidyl ether of bisphenol A. The reaction was conducted at reflux in a mixture of THF and methanol. The polymer, illustrated in Eq. (6.24) was formed 83% yield. The polymer was appparently quite stable, surviving aging tests conducted over a two-year period. 

The alkali-catalysed methanolysis of poly(2,2-bis(4-hydroxyphenyljpropane carbonate) (PC) in a mixture of methanol (MeOH) and toluene or dioxane was studied. The treatment of PC in meOH, with a catalytic amount of sodium hydroxide, yielded only 7% bisphenol A. Using a mixed solvent of MeOH and toluene completely depolymerised PC to give 96% free bisphenol A in solid form and dimethyl carbonate in solution. The eharaeteristies of the catalysis are discussed together with the pseudo-first rate kinetics of the depolymerisation. The reaetion eonditions were investigated to facilitate the reeyeling of PC plasties. 17 refs. 

Various bisphenol derivatives were also polymerized by peroxidase under selected reaction conditions, yielding soluble phenolic polymers. Bisphenol-A was polymerized by peroxidase catalyst to give a polymer soluble in acetone, DMF, DMSO, and methanol. The polymer was produced in higher yields using SBP as a catalyst. This polymer showed a molecular weight of 4 x 10 and a 7g at 154°C. The HRP-catalyzed polymerization of 4,4 -biphenol produced a polymer showing high thermal stability. ... 

The anthors also snccessfnlly catalysed the formation of PC with 39-R via oxidative carbonylation of bisphenol A [47], Under similar conditions with 39- Bu, a PC with = 24000 and = 9400 was obtained in 80% yield. The... 

Bisphenol AF/Bisphenol A (unit ratio) Yield (%) Bred (dl/g)... 

Copoly(formal)s (8) with high reduced viscosities are readily obtained in high yields irrespective of the feed ratio ofBisphenol AF (1) and Bisphenol A (4) (Table 9.6). 

Hexafluoroisopropylidene-unit-containing aromatic poly(ether ketone)s were first synthesized from an alkaline metal salt of Bisphenol AF (1) and 4,4 -difluoro-benzophenone.14 Cassidy and co-workers prepared hexafluoroisopropylidene-unit-containing poly(ether ketone)s by condensing 2,2-bis[4-(4-fluorobenzoyl)-phenyl]-l,l,l,3,3,3-hexafluoropropane (9) and 2,2-bis[4-(4-fluorobenzoyl)-phenyljpropane (10) with Bisphenol AF (1) or Bisphenol A (4) (Scheme 7).15 The reactions are nucleophilic aromatic displacements and were conducted in DMAc at 155- 160°C with an excess of anhydrous potassium carbonate. After 3 to 6 h of reaction, high-molecular-weight poly(ketone)s are obtained in high yields. 

Interfacial condensation of sodium salt of bisphenol A and phosgene also yields the same polymer ... 

The PEs of BPA and BP-5 in a normal experimental medium, 5% CDFBS-supplemented medium and synthetic ITDME medium are presented in Table 7.3.5. The addition of 0.1 p.M BPA to 10% CDHuS or 5% CDFBS supplemented medium increases cell proliferation as effectively as estradiol. BPA was also tested in the presence of an antiestrogen, producing inhibition of the PE associated with BPA. The PEs of chlorinated bisphenols are shown in Table 7.3.5. It was significantly greater than one for all the compounds tested. In comparison with the RPE of estradiol, all the positive compounds showed a full to partial agonistic response, producing cell yields that ranged from 85% of estradiol-induced yield for bisphenol-A to 30% for the bisphenol-A derivative tetrachlorine. 

Study of the effect of small amounts of water in the liquid, organic phase on the polymerization of bisphenol-A and HFB in several solvents.[14] Solvents were rigorously dried and assayed for water content by potentiometric Karl Fischer titration. A series of polymerizations catalyzed and uncatalyzed in each solvent were carried out in which the water content was increased incrementally. Polymer yields and inherent viscosities were determined as a function of water content in each solvent. The optimal water content expressed as the mole ratio of water to catalyst shows that the necessary water level varies substantially with solvent (see Table V and Figure 1-3). 

The thermoset included here is derived from bisphenol-A dicya-nate. It can be thermally trimerized yielding a triazine or cyanurate network (8,9,10) as seen in the reaction scheme (Table 1). The critical molecular weight between crosslinks is relatively low, resulting in an extremely tight, brittle network. The material is usually used as a prepeg because a total cure produces a hard, infusible, and insoluble matrix. It possesses excellent adhesive properties and is currently used as a metal coupling agent. It offers many superior properties relative to conventional epoxies derived from bisphenol-A. 

A 2-year feeding study with mice and rats yielded no evidence of carcinogenic effects. Recent extensive reviews have concluded that bisphenol A is nongenotoxic in vivo ... 

Statistical copolymerization of ethylene glycol and 1,4-butanediol with dimethyl ter-ephthalate results in products with improved crystallization and processing rates compared to poly(ethylene terephthalate). Polyarylates (trade names Ardel, Arylon, Durel), copolymers of bisphenol A with iso- and terephthalate units, combine the toughness, clarity, and proce-sibility of polycarbonate with the chemical and heat resistance of poly(ethylene terephthalate). The homopolymer containing only terephthalate units is crystalline, insoluble, sometimes infusible, and difficult to process. The more useful copolymers, containing both tere- and isophthalate units, are amorphous, clear, and easy to process. Polyarylates are used in automotive and appliance hardware and printed-circuit boards. Similar considerations in the copolymerization of iso- and terephthalates with 1,4-cyclohexanedimethanol or hexa-methylene diamine yield clear, amorphous, easy-to-process copolyesters or copolyamides,... 

But not only palladium(O) complexes can activate CO or O2, also palla-dium(II) complexes have been reported to be active in the presence of carbon monoxide or dioxygen as it was shown in the direct synthesis of polycarbonate from CO and phenol or bisphenol A [79,80]. The authors could confirm the positive influence of the NHC ligand comparing the activity and reactivity of the palladium-carbene complex with the corresponding PdBr2 catalyst. The molecular weights and yields of the polycarbonates improved with increasing steric hindrance of the substituents in the l,T-position of the car-bene complex. 

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