2- hydroxy-1.4-phenylene

A major type of epoxy monomers is that derived from the reaction of bis(4-hydroxy phenylene)-2,2 propane (called bisphenol A) and 1-chloropropene 2-oxide (called epichlorohydrin) in the presence of sodium hydroxide (condensation reaction). The structure of the major product, bisphenol A digly-cidyl ether (DGEBA) and its condensed forms (Table 2.7a), is dependent upon the stoichiometry of the reactants. 

Chemical Name 2,2-Dimethylpropanoic acid 4-[ 1-hydroxy-2-(methylamino)ethyl] -1,2-phenylene ester... 

Only a few building blocks are available for the synthesis of ester-containing rigid mesogenic units, namely dihydroxy-, dicarboxy-, or (hydroxy, carboxy)-l,4-phenylenes, 4,4,-biphenylenes, and 2,6-, 1,4-, or 1,5-naphthylenes (Table 2.15). 

The photodegradation of synthetic polymers can be prohibited (or at least reduced) upon addition of UV-stabilizers. These compounds transform the absorbed light energy into thermal energy thus preventing all sorts of photochemically initiated reactions. Films of poly-(m-phenylene-isophthalamide) were used which contained appropriate amounts of UV-stabilizers of the 2-(2 -hydroxy-5 -methylphenyl)benzotriazole type or their 21-methoxy derivatives. The following results were obtained ... 

CC Wu, JKM Chun, PE Burrows, JC Sturm, ME Thompson, SR Forrest, and RA Register, Poly (p-phenylene vinylene)/tris(8-hydroxy) quinoline aluminum heterostructure light emitting diode, Appl. Phys. Lett., 66 653-655, 1995. 

In a pyrogram of Bisphenol A poly(formal) (6), the peak products are identified as a-methylstyrene, phenol, 4-hydroxy-a-methylstyrene, and isopropyl phenol by Py-GC/MS. These products are identical with the degradation products from Bisphenol A. In addition to the decomposition products of Bisphenol A, 4-isopropenyl anisole is also identified as a product. The pyrograms of Bisphenol AF poly(formal) (7) contain only two major species, pentafluoroisopropenyl benzene (product T) and pentafluoroisopropenyl anisole (product 2 ). They correspond to a-methylstyrene, 4-hydroxy-amethylstyrene from Bisphenol A poly(formal) (6) and are produced by the cleavage of phenylene-oxy bonds and oxy-methylene bonds according to (Scheme 6). 

Similar explanations almost certainly account for the very large effective molarities found for lactonization of the hydroxy acids B.1.13, B.2.16 and B.2.25 (Table 12). All these compounds have the basic tetrasubstituted ethylene (here o-phenylene) structure found in the dialkylmaleic acid system further destabilized by substituents in the 3 and 6 positions of the benzene ring which also act to prevent bond angle spreading of the two inner substituents. (The effects of 3- and 6-substituents on this type of cyclization reaction are well known, and are shown for example by the range of EM s for compounds... 

In concluding this section, we should touch upon phase boundary concentration data for poly(p-benzamide) dimethylacetamide + 4% LiCl [89], poly(p-phenylene terephthalamide) (PPTA Kevlar)-sulfuric acid [90], and (hydroxy-propyl)cellulose-dichloroacetic acid solutions [91]. Although not included in Figs. 7 and 8, they show appreciable downward deviations from the prediction by the scaled particle theory for the wormlike hard spherocylinder. Arpin and Strazielle [30] found a negative concentration dependence of the reduced viscosity for PPTA in dilute Solution of sulfuric acid, as often reported on polyelectrolyte systems. Therefore, the deviation of the Ci data for PPTA in sulfuric acid from the scaled particle theory may be attributed to the electrostatic interaction. For the other two systems too, the low C] values may be due to the protonation of the polymer, because the solvents of these systems are very polar. 

Di(hydroxyethoxy)-beniene or Di(hydroxy-ethyl) -phenylene Ether. See Bis(hydroxy-ethoxy)-benzene in Vol 2, p B145-R... 

The maleimide functionality has also been utilized as a modifying group to obtain polymers crosslinkable by free radical chemistry. Thus, hydroxy-terminated poly(oxy-2,6-dimethyl-1,4-phenylene) (164) was treated with p-maleimidobenzoyl chloride (165) to obtain resin (166 Scheme 81) (72FRP2122181). Resin (166) melted at 155 °C and could be coated on to... 

Andreetti, G. D., Ungaro, R., Pochini, A., Crystal and molecular structure of cyclo quarter[(5-t-butyl-2-hydroxy-l, 3-phenylene)methylene] toluene (1 1) claihraie. J. Chem. Soc., Chem. Commun. 1979, 1005-1007. 

N,N-Bis -(2-hydroxy ethyl)-/ -pheny lene diamin e N,N-Bis -(2-hydroxyethyl)-/ -phenylene diamin e N,N-Bis -(2-hydroxyethyl)-/ -phenylene diamin e N,N-Bis -(2-hydroxyethyl)-/ -phenylene diamin e N,N-Bis -(2-hydroxy ethy l)-p-pheny len ediamin e N,N-Bis -(2-hydroxyethy 1)-p -phenylene diamin e 4-Amino-3-methylphenol 4-Amino-3-methylphenol 4-Amino-3-methylphenol 4-Amino-3-methylphenol 4-Amino-3-methylphenol 4-Amin o-3-methylp heno 1... 

The potential of the m-benziporphyrin skeleton to produce aromatic macrocycles, foreseeable in the above discussion of its hypothetical tautomers, was actually revealed by introduction of hydroxy groups on the phenylene ring. These functionalities serve as additional tautomerization sites, which become effective aromaticity switches in appropriately designed systems. Theoretical insight into the switching capabilities of hydroxybenziporphyrins was gained from a theoretical survey of relative stabilities and aromatic character of various hydroxybenziporphyrin tautomers [287, 288], which was concurrently verified by experimental work (Table 2) [250],... 

The discussion of the influence of the interphase need not be limited to just linear polyethylenes. Interphases of several nm have been reported in polyesters and poly-hydroxy alkanoates. One major difference between the interphase of a flexible polymer like polyethylene and semi-flexible polymers like PET, PEN and PBT is the absence of regular chain folding in the latter materials. The interphase in these semi-flexible polymers is often defined as the rigid amorphous phase (or rigid amorphous fraction, RAF) existing between the crystalline and amorphous phases. The presence of the interphase is more easily discerned in these semi-flexible polymers containing phenylene groups, such as polyesters. 

CN ( )-2,2-dimethylpropanoic acid 4-[l-hydroxy-2-(mcthylamino)ethyl]-l,2-phenylene ester... 

Polyester macromonomers were also prepared by Hudecek et al. 92) who reacted polyesters with hydroxy end groups. With the mono-adduct of 2-hydroxyethyl methacrylate (HEMA) and methylene-bis-phenylene isocyanate (MD1) one obtains ... 

Hydroxy quinoline is obtained by the reaction between o.phenylene diamine and dichloro acetic acid... 

PB PBI PBMA PBO PBT(H) PBTP PC PCHMA PCTFE PDAP PDMS PE PEHD PELD PEMD PEC PEEK PEG PEI PEK PEN PEO PES PET PF PI PIB PMA PMMA PMI PMP POB POM PP PPE PPP PPPE PPQ PPS PPSU PS PSU PTFE PTMT PU PUR Poly(n.butylene) Poly(benzimidazole) Poly(n.butyl methacrylate) Poly(benzoxazole) Poly(benzthiazole) Poly(butylene glycol terephthalate) Polycarbonate Poly(cyclohexyl methacrylate) Poly(chloro-trifluoro ethylene) Poly(diallyl phthalate) Poly(dimethyl siloxane) Polyethylene High density polyethylene Low density polyethylene Medium density polyethylene Chlorinated polyethylene Poly-ether-ether ketone poly(ethylene glycol) Poly-ether-imide Poly-ether ketone Poly(ethylene-2,6-naphthalene dicarboxylate) Poly(ethylene oxide) Poly-ether sulfone Poly(ethylene terephthalate) Phenol formaldehyde resin Polyimide Polyisobutylene Poly(methyl acrylate) Poly(methyl methacrylate) Poly(methacryl imide) Poly(methylpentene) Poly(hydroxy-benzoate) Polyoxymethylene = polyacetal = polyformaldehyde Polypropylene Poly (2,6-dimethyl-l,4-phenylene ether) = Poly(phenylene oxide) Polyp araphenylene Poly(2,6-diphenyl-l,4-phenylene ether) Poly(phenyl quinoxaline) Polyphenylene sulfide, polysulfide Polyphenylene sulfone Polystyrene Polysulfone Poly(tetrafluoroethylene) Poly(tetramethylene terephthalate) Polyurethane Polyurethane rubber... 

Coupling carbonyl compounds with aromatic amines bearing amino, hydroxy, or thiol groups in o -positions is known to be a general method for the synthesis of 1,3-benzazoles, with the intermediate formation of the respective 2,3-dihydro derivatives. No heterocyclization occurs, however, in the reaction of o-phenylene-diamines or o-aminophenols with /i-quinones. In these cases, the reaction stops at the stage of formation of the deeply colored quinoneimine 105 which is similar to that obtained by the previously studied reaction of a variety of / -substituted anilines with derivatives of p -bcn/oquinonc.6 Compounds 10 do not undergo cyclization under heating or irradiation of its solution (Scheme 4). 

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