Polymers, nitro

Nitromethane can form azeotrope with many organic solvents. Additionally, it can dissolve certain polymers, nitro compounds, and nitrate compounds. Nitromethane is partially miscible with water at 20 °C, the solubility of nitromethane in water is 9.5 % (by volume) or 10.5 % (by mass), meanwhile, the solubility of water in nitromethane is 1.75 % (by mass). Generally, the miscibility of nitromethane increases with the rise of temperature. Dry nitromethane is a neutral substance, thus it possesses excellent storage stabihty. After being stored for certain period of time, wet nitromethane will become acidic, which making it capable of corroding metals, however, adding a small amount of phosphoric acid or phosphate can effectively inhibit corrosion. 

Totally degraded in 1-2 months principal products hydroquinone, 4-nitrocatechol, and a dark, acidic polymer nitro group reduced to amino and azo group... 

Another commercial appHcation of nucleophilic reactions of nitro-free duoroaromatics is the manufacture of polyetheretherketone (PEEK) high performance polymers from 4,4 -diduoroben2ophenone [345-92-6], and hydroquinone [121-31-9] (131) (see PoLYETHERS, AROMATIC). 

Polymers. AH nitro alcohols are sources of formaldehyde for cross-linking in polymers of urea, melamine, phenols, resorcinol, etc (see Amino RESINS AND PLASTICS). Nitrodiols and 2-hydroxymethyl-2-nitro-l,3-propanediol can be used as polyols to form polyester or polyurethane products (see Polyesters Urethane polymers). 2-Methyl-2-nitro-l-propanol is used in tires to promote the adhesion of mbber to tire cord (qv). Nitro alcohols are used as hardening agents in photographic processes, and 2-hydroxymethyl-2-nitro-l,3-propanediol is a cross-linking agent for starch adhesives, polyamides, urea resins, or wool, and in tanning operations (17—25). Wrinkle-resistant fabric with reduced free formaldehyde content is obtained by treatment with... 

I itro-DisplacementPolymerization. The facile nucleophilic displacement of a nitro group on a phthalimide by an oxyanion has been used to prepare polyetherimides by heating bisphenoxides with bisnitrophthalimides (91). For example with 4,4 -dinitro monomers, a polymer with the Ultem backbone is prepared as follows (92). Because of the high reactivity of the nitro phthalimides, the polymerkation can be carried out at temperatures below 75°C. Relative reactivities are nitro compounds over halogens, Ai-aryl imides over A/-alkyl imides, and 3-substituents over 4-substituents. Solvents are usually dipolar aprotic Hquids such as dimethyl sulfoxide, and sometimes an aromatic Hquid is used, in addition. 

Condensation ofDianhydrides with Diamines. The preparation of polyetherknides by the reaction of a diamine with a dianhydride has advantages over nitro-displacement polymerization sodium nitrite is not a by-product and thus does not have to be removed from the polymer, and a dipolar aprotic solvent is not required, which makes solvent-free melt polymerization a possibiUty. Aromatic dianhydride monomers (8) can be prepared from A/-substituted rutrophthalimides by a three-step sequence that utilizes the nitro-displacement reaction in the first step, followed by hydrolysis and then ring closure. For the 4-nitro compounds, the procedure is as follows. 

Diazo Coupling Reactions. Alkylphenols undergo a coupling reaction with dia2onium salts which is the basis for the preparation of a class of uv light stabilizers for polymers. The interaction of orxv i -nitrobenzenediazonium chloride with 2,4-di-/ r2 -butylphenol results in an azo-coupled product (30). Reduction of the nitro group followed by m situ cyclization affords the benzottiazole (31) (19). 

Solvent for Displacement Reactions. As the most polar of the common aprotic solvents, DMSO is a favored solvent for displacement reactions because of its high dielectric constant and because anions are less solvated in it (87). Rates for these reactions are sometimes a thousand times faster in DMSO than in alcohols. Suitable nucleophiles include acetyUde ion, alkoxide ion, hydroxide ion, azide ion, carbanions, carboxylate ions, cyanide ion, hahde ions, mercaptide ions, phenoxide ions, nitrite ions, and thiocyanate ions (31). Rates of displacement by amides or amines are also greater in DMSO than in alcohol or aqueous solutions. Dimethyl sulfoxide is used as the reaction solvent in the manufacture of high performance, polyaryl ether polymers by reaction of bis(4,4 -chlorophenyl) sulfone with the disodium salts of dihydroxyphenols, eg, bisphenol A or 4,4 -sulfonylbisphenol (88). These and related reactions are made more economical by efficient recycling of DMSO (89). Nucleophilic displacement of activated aromatic nitro groups with aryloxy anion in DMSO is a versatile and useful reaction for the synthesis of aromatic ethers and polyethers (90). 

Nitro-substituted indolino spiroben2opyrans or indolino spironaphthopyrans are photochromic when dissolved in organic solvents or polymer matrices (27). Absorption of uv radiation results in the colorless spiro compound [1498-88-0], C22H2gN202, being transformed into the colored, ring-opened species. This colored species is often called a photomerocyanine because of its stmctural similarity to the merocyanine dyes (see Cyanine dyes). Removal of the ultraviolet light source results in thermal reversion to the spiro compound. 

Passive transdermal dehvery systems on the market tend to be either matrix or membrane controUed. In matrix devices, the stmctural and molecular characteristics of the dmg-polymer matrix determine dmg release. Examples of polymer matrix-controUed diffusional systems for angina prophylaxis include Nitro-Dur and Nitrodisc, which provide transdermal dehvery of nitroglycerin [55-63-0], and Erandol, a tape that releases isosorbide dinitrate [87-33-2]. Matrix diffusional systems have been used for dehvering dmgs with a wide therapeutic index. 

The Nitro-dur system, marketed by Key Pharmaceuticals, Inc., contains nitroglycerin in acryUc-based polymeric adhesives with a cross-linking agent for polymer stabiUty. This depot of dmg provides a continuous source of active ingredient. An impermeable backing prevents release of nitroglycerin away from the skin. The systems are individually sealed in a paper polyethylene-foil pouch (81). 

Carbazole, 2-hydroxy-reactions with citral, 4, 235 Carbazole, 2-hydroxy-9-methyl-synthesis, 4, 294 Carbazole, N-hydroxymethyl-as metabolite of carbazole, 1, 230 Carbazole, N-isopropyl-PE spectroscopy, 4, 190 Carbazole, A7-methyl- N NMR, 4, 175 X-ray spectroscopy, 4, 163 Carbazole, 1-nitro-synthesis, 4, 282 Carbazole, tetrahydro-dehydrogenation, 4, 282, 312 synthesis, 4, 107, 337, 353 Carbazole, 1,2,3,4-tetrahydro-reduction, 4, 255, 256 synthesis, 4, 312, 325, 352 Carbazole, 1,2,3,4-tetrahydro-1 -oxo-synthesis, 4, 337 Carbazole, 9-trifluoroacetyl-synthesis, 4, 218 Carbazole, vinyl-polymers, 1, 275, 301 Carbazole, 9-vinyl-copolymer... 

Furan, 2,3-dihydro-5-methyl-polymers, 1, 276 Furan, 2,3-dihydro-3-methylene- H NMR, 4, 577 Furan, 2,5-dihydro-2-methylene- H NMR, 4, 577 tautomerism aromaticity and, 4, 595 Furan, 2,5-dihydro-2-nitro-structure, 4, 550 Furan, 2,3-dihydroxy-tautomerism, 4, 37 Furan, 2,4-dihydroxy-tautomerism, 4, 37 Furan, 3,4-dihydroxy-tautomerism, 4, 37 Furan, 2,5-diiodo-nitration, 4, 602 synthesis, 4, 712 Furan, 3,4-diiodo-reactions, 4, 650 Furan, 2,3-dimethoxy-synthesis, 4, 625, 648 Furan, 2,5-dimethoxy-synthesis, 4, 648 Furan, 3,4-dimethoxy-cycloaddition reactions, 4, 64, 625 lithiation, 4, 651 reactions... 

Imidazole-5-carboxamide, l-methyl-4-nitro-mass spectra, 5, 359 Imidazole-4-carboxanilide, 1-methyl-synthesis, 5, 435 Imidazolecarboxylic acid, vinyl-polymers, 1, 281 Imidazole-2-carboxylic acid chlorination, 5, 398 mass spectra, 5, 360 synthesis, 5, 474... 

Imidazolidin-2-one, l-(5-nitro-2-thiazolyl)-pharmacological activity, 6, 328 Imidazolidin-4-one, l-aryl-3-phenyl-2-thioxo- C NM S, 355 Imidazolidinones C NMR, 5, 355 Imidazolidin-2-ones nucleophilic displacement, 5, 428 polymers, 1, 279-280 reactivity, 5, 376 synthesis, 5, 466, 471 Imidazolidin-4-ones synthesis, 5, 468 Imidazoline, 2-alkyl-synthesis, 5, 463 Imidazoline, 2-amino-applications, 5, 498 Imidazoline, 2-aryl-synthesis, 5, 463 Imidazoline, 2-methyl-synthesis, 5, 487 Imidazoline, 2-nitroamino-synthesis, 5, 471 2-Imidazoline, 2-arylamino-tautomerism, 5, 368 2-Imidazoline, 1-benzyl-methylation, 5, 425 2-Imidazoline, 1,2-diaryl-synthesis, 5, 463... 

Quinazoline-2,4( 1 H,3H)-dione, 7-nitro-synthesis, 3, 110 Quinazolihediones mass spectra, 2, 22 polymers, 1, 298 Quinazoline-2,4( 1 H,3 H)-diones synthesis, 3, 106 O-trimethylsilylation, 3, 91 Quiriazolines addition reactions, 3, 73... 

In addition to its water solubility poly(vinyl pyrrolidone) is soluble in a very wide range of materials, including aliphatic halogenated hydrocarbons (methylene dichloride, chloroform), many monohydric and polyhdric alcohols (methanol, ethanol, ethylene glycol), some ketones (acetyl acetone) and lactones (a-butyrolactone), lower aliphatic acids (glacial acetic acid) and the nitro-paraffins. The polymer is also compatible with a wide range of other synthetic polymers, with gums and with plasticisers. 

Aromatic fluorodenitration was first discovered in the reaction of polychloro-nitrobenzenes with potassium fluoride, when 2,3,5,6-tetrachlorofluorobenzene was prepared in 37% yield from 2,3,5,6-tetrachloronitrobenzene 105] The technique has been adapted to prepare aryl fluorides from other activated nitro aromatics for applications in pharmaceutical and polymer chemistry (equation 31) Fluorodenitration also has been applied to prepare radiolabeled ( F) fluo-roaromatics [74, 106]... 

A more effecdve catalyst for the Hetuy reacdon is a polymer-supported base such as amberlyst A-31. Various fi-nitro alcohols can be obtained v/ith the help of amberlyst v/ith or without solvent fEq, 3,14, A recent report claims that amberlite IRA-430 COH-formi or DOWEX-1 COH-formi is more effecdve for the Henry reacdon than amberlyst A-31/ Poly-... 

Dehydration of fi-nitro alcohols using DCC gives a mixnire of E/Z nitroaikenes. The pure fE -isomers are obtained on treatment with catalytic amounts of triethylamine or polymer-bound triphenylphosphme (TPP fEq. 3.281. When (Z) nitroaikenes are desired, the addition of PhSeNa to the E/Z mixnire and protonadon at -78 "C fohowed by oxidadon with gives fZi-nitroalkenes fEq. 3.29. ... 

Recently, Dutta and Maiti [21] reported nitro displacement polymerization of the bisphenol dianion with the sulfone activated dinitro aromatic compounds. In addition, there have been recent reports of the development of functionalized PEEK [22] and polyether sulfone ketone (PESK) [23] that are comparable to commercially available high performance polymers. 

We also found the saturation kinetics for alkaline hydrolyses of 44 (PNPA), 3-nitro-4-acetoxybenzoic acid 56 (NABA), and 3-nitro-4-acetoxybenzenearsonie acid 57 (NABAA) in the presence of QPVP1025. If ester-polymer complex formation occurs prior to the attack of OH-, Eq. (5) holds, according to Bunton etal. 103 where K is the equilibrium association constant of polyelectrolyte (PE) and ester (S), and kt the first-order rate coefficients1035, PE, S, and P indicate the poly-... 

The term nitro polymer refers to nitrated polymeric compds, usually thermoplastic, having nitro—carbon bonding, viz ... 

Sweeney K.W. Bills, Application of Nitro-polymers to Smokeless Propellants , Report No 1104, Aerojet-General Corp, Azusa, Calif ... 

Nitro Ethyl Acrylate Polymers. See Vol 6, E201-R to E202-R... 

Of the many nitro polymers developed as propints by Aerojet General Corp, one polyamide polymer resulted which can be considered an expl and is presented below ... 

Toxicity. Unknown, but should be hazardous considering other glycidyl compds Refs 1) PJ. Blatz et al, Research in Nitro Polymers and Their Application to Solid Smoke-... 

CH3.CH2.CiC.NO5, mw 99.10, N 14.14%-, OB to C02 —137.24%, red, sticky, odiferous oil. Prepn from l-bromo-l-nitro-butene-(l) by reacting with methylamine in ethanol The monomer explds when heated Polymer... 

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