Diphenyl terephthalate

Diphenyl Terephthalate—Diphenyl Isophthalate-Bisphenol-A Melt Polyesterification... 

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. 

Diphenyl sulfone (DPS), 338 Diphenyl terephthalate-diphenyl isophthalate-bisphenol-A melt poly esterification, 111-112 Direct polyesterification, 63-69 Distinctness of image (DOI), 245 Divergent method, 8... 

VII) poly (2,4(8-vinylpyridyl)diphenyl terephthalate) [poly(2,4-VPDPT)]... 

We found that cyclic benzeneboronic anhydride (BBA), diphenyl carbonate (DPC) (4), diphenyl terephthalate (DPT) (5), diphenyl oxalate (DPO) (5), diphenyl malonate (DPM) (5), tetraphenyl orthocarbonate (POC) (6), hexaphenyl orthoterephthalate (POT) (7) are suitable compounds as chain extenders. 

The number 27 in Figure 7 was the result of the polycondensation with successive additions of 0.47 mole % of diphenyl terephthalate and 0.23 mole % of tetraphenyl orthocarbonate in the same reaction system. These chain extenders were added directly to the polycondensation reaction system under high vacuum. 

Elimination of Phenol. The equilibrium constants of the reactions indicated by Reactions 1 and 6 were measured at 275°C to explain the remarkable effect of diphenyl terephthalate in accelerating the PET polycondensation by elimination of phenol (10). 

Diphenyl Terephthalate. In Reaction 7, the effect of diphenyl terephthalate in accelerating the polycondensation reaction can be explained by assuming kJk-3—k2lk-2-... 

Diphenyl terephthalate (DPT) was prepared by interfacial reaction of sodium phenoxide in water and terephthaloyl chloride (TPC) in methylene chloride, using benzyl triethylammonium chloride as catalyst, followed by washing with hot water and recrystallization from toluene. The yield was usually 90% or higher. 

Diphenyl terephthalate was obtained with a conversion of 99.9% from a mixture of terephthalic acid, phenol, some tetra-n-butyl-1,3-diphenoxydistannoxane and platinum wire (pretreated with hydrogen) heated for 2 hours in an autoclave at 260°C under hydrogen (ref.8). 

The styrylpyridine based polyarylates and their model compounds were synthesized. The order of the relative char yield and oxygen indices were polyarylates > p,p -bis(B-2-vinylpyridyl)diphenyl terephthalate (p,p -BVPDPT) = p,p -2,6-(3-2-vinylpyridyl)diphenyl dibenzoate >(p,p -2,6 -2,6-(B-2-vinylpyridyl)phenyl benzoate (p-VPPB). This is also probably due to the Diels-Alder reaction of the C=C double bonds present in the main chain with the pryidine group. The result is a highly crosslinked C-C bond char. The styrylpyridine based model compounds of the ester and carbonate underwent the Photo-Fries arrangement when irradiated with UV light to give o-hydroxybenzophenone related structures. 

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