Bis 4-hydroxyphenyl

Reduction. These hydroxybenzaldehydes can be reduced by catalytic hydrogenation over palladium or platinium to yield the corresponding hydroxybenzyl alcohols, but the electrolytic reduction in an alkaline medium gives the coupling product l,2-bis(4-hydroxyphenyl)ethane-l,2-diol in very good yield from 4-hydroxybenzaldehyde (49—51). 

The most common commercial polycarbonate [24936-68-3] is prepared from 2,2-bis (4-hydroxyphenyl)propane, that is, bisphenol A [80-05-7] and has the general stmcture ... 

Polyarylether Ketones. The aromatic polyether ketones are tme thermoplastics. Although several are commercially available, two resins in particular, poly ether ether ketone [31694-16-3] (PEEK) from ICI and poly ether ketone ketone (PEKK) from Du Pont, have received most of the attention. PEEK was first synthesized in 1981 (20) and has been well studied it is the subject of numerous papers because of its potential use in high performance aircraft. Tough, semicrystalline PEEK is prepared by the condensation of bis(4-fiuorophenyl) ketone with the potassium salt of bis(4-hydroxyphenyl) ketone in a diaryl sulfone solvent, such as diphenyl sulfone. The choice of solvent is critical other solvents, such as Hquid HE, promote the reaction but lead to premature low molecular-weight crystals, which do not exhibit sufficient toughness (21). 

As already indicated, the polycarbonates may be produced from a wide range of polyfunctional hydroxy compounds. In practice only the diphenyl compounds have proved of much interest and the only polycarbonate of commercial significance is derived from bis-phenol A 2,2-bis-(4-hydroxyphenyl) propane. 

To produce resins for paints and for electrical insulation, film cast from solution copolymers based on bis-phenol A and bis-phenol Z (l,l-bis-(4-hydroxyphenyl)cyclohexane) have been used. 

Stannett and Meyers have reported that crystallisation may reduce the nitrogen permeability by 50%. The moisture vapour permeability of the polycarbonate from l,l-bis-(4-hydroxyphenyl)cyclohexane has been quoted by Schneir as being somewhat below half that of the bis-phenol A polymer (1.7, c.f. 3.8 units). 

Chemical Designations - Synonyms 2,2-Bis(4-Hydroxyphenyl)Propane p,p -Dihydroxy-... 

The most widely used monomer compd is 2,2-Bis (4-hydroxyphenyl)-propane or bisphenol-A. For a description of this monomer see Vol 2, B147-R- The properties of the polymer or resin comprised of this monomer are presented next ... 

The steric requirements of the enhanced interaction between arylsulfinyl or arylsulfonyl groups and the benzene ring in bis(4-hydroxyphenyl)sulfoxides or sulfones were examined by Oae and colleagues through the introduction of methyl groups in two or four of the positions ortho to SO or S02. As in the work described earlier for S02Me, effective values for the combined influence of the substituents o (obs.) were determined and compared with o (calc.) computed on the basis of strict additivity of substituent effects on the dissociation... 

TABLE 4. First pKa values of bis(4-hydroxyphenyl)sul foxides in 50% water-ethanol at 25 °C and related Hammett (r-values (after Reference 33)... 

Bis(arylsulphonyl)alkanes 654 Bis(/ -hydroxyalkyl) sulphones 642 Bis(4-hydroxyphenyl) sulphones, pXa values of 587, 588... 

Bis(4-hydroxyphenyl) sulphones butadienyl - see Butadienyl sulphones chiral - see Chiral sulphones complexes of 573 cyclic - see Cyclic sulphones cycloalkenyl - see Cycloalkenyl sulphones cycloalkyl aryl - see Cycloalkyl aryl sulphones... 

Bis(4-hydroxyphenyl) sulphoxides butadienyl - see Butadienyl sulphoxides carbamoyl - see Carbamoyl sulphoxides chiral - see Chiral sulphoxides complexes of 567-573 conformational analysis of 84-89 cyclic - see Cyclic sulphoxides cyclopentanone - see Cyclopentanone sulphoxides... 

To cold diionyl chloride (1.31 g, 11 mmol) in an ice-water bath, pyridine (10 mL) is added slowly for 10 min to keep the reaction temperature low. The reaction medium is stirred for 30 min. Then, a mixture of isophdialic acid (0.41 g, 2.5 mmol) and terephdialic acid (0.41 g, 2.5 mmol) in pyridine (10 mL) is added slowly for 10-20 min to control the reaction temperature. The cooling badi is then removed and the reaction mixture is stirred at room temperature for 20 min. 2,2-Bis(4-hydroxyphenyl)propane (bisphenol-A, 1.14 g, 5 mmol) in pyridine (10 mL) is added all at once to the mixture, and the whole solution is heated to 80°C (bath temperature) for 4 h. The resulting viscous solution is diluted with pyridine and poured into methanol to precipitate the polymer, which is washed in boiling methanol and dried. The inherent viscosity of polymer is 2.2 dL/g (determined in 60/40 phenol-1.1.2.2-tetrachloroethane at 30°C)... 

Experiment with addition of diphenyl carbonate Diphenyl terephthalate, 31.8 g (0.1 mol), 28.62 g (0.09 mol) of diphenyl isophthalate, and 2.37 g (0.011 mol) of diphenyl carbonate are polycondensed with 45.6 g (0.2 mol) of 2,2-bis(4-hydroxyphenyl)propane (bisphenol-A) under the preceding conditions. A slighdy brownish, extremely tough, noncrystalline polyester is obtained with an inherent viscosity equal to 0.56 dL/g. The softening point of the polyester is equal to 200°C and the melting range is 215-285°C. 

Herbert and Hay reported a bisphenolic monomer, 3,8-bis(4-hydroxyphenyl)-A-phenyl-1,2-naphthalimide (Table 6.1), as well as its corresponding polyf V-phenyl imido aryl ether sulfone) via transimidization reactions with hydrazine monohydrate, aliphatic amines, and an amino acid.193 These polysulfones with... 

Using 4,4,-bis(4-hydroxyphenyl)pentanoic acid (BHPA)196 197 as comonomer, some polysulfones with pendent carboxylic groups were successfully synthesized.198199 Table 6.1 shows the structure of BHPA. The functional groups can be used for the preparation of graft copolymers. 

Bis(4-hydroxyphenyl)-lV-phenyl-l,2-naphthalimide, 354, 355 4,4 -Bis(4-hydroxyphenyl)pentanoic acid (BHPA), 355, 356 Bisnitroimides, 346 Bisphenol-A, 112 Bisphenol-A-based benzoxazines... 

Polydimethylsiloxane based multiblock copolymer systems containing 1,1-dichloro-2,2-bis(4-hydroxyphenyl)ethylene polycarbonate units and phenolphthalein polycarbonate units were synthesized and evaluated231 . Both copolymer systems showed good phase separation, increased rubbery character and improved processa-... 

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