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Polyoxymethylene glycols

Paraformaldehyde [30525-89-4] is a mixture of polyoxymethylene glycols, H0(CH20) H, with n from 8 to as much as 100. It is commercially available as a powder (95%) and as flake (91%). The remainder is a mixture of water and methanol. Paraformaldehyde is an unstable polymer that easily regenerates formaldehyde in solution. Under alkaline conditions, the chains depolymerize from the ends, whereas in acid solution the chains are randomly cleaved (17). Paraformaldehyde is often used when the presence of a large amount of water should be avoided as in the preparation of alkylated amino resins for coatings. Formaldehyde may also exist in the form of the cycHc trimer trioxane [110-88-3]. This is a fairly stable compound that does not easily release formaldehyde, hence it is not used as a source of formaldehyde for making amino resins. [Pg.323]

Polymers produced by methods as described above have thermal stabilities many times greater than those obtained by the earlier bulk and solution methods of Staudinger. Staudinger had, however, shown that the diacetates of low molecular weight polyoxymethylenes (I) (polyformaldehydes) were more stable than the simple polyoxymethylene glycols (II) (Figure 19.2). [Pg.534]

Chemical Designations - Synonyms Fonnaldehyde polymer Polyformaldehyde Polyfooxymethylene Polyoxymethylene glycol Chemical Formula HO(CHjO) H. [Pg.305]

Two-shot techniques for acyclic diene metathesis, 435-445 for polyamides, 149-164 for polyimides, 287-300 for polyurethanes, 241-246 for transition metal coupling, 483-490 Anionic deactivation, 360 Anionic polymerization, 149, 174 of lactam, 177-178 Apolar solvents, 90 Aprotic polar solvents, 185, 338 Aprotic solvents, low-temperature condensation in, 302 Aqueous coating formulations, 235 Aqueous polyoxymethylene glycol, depolymerization of, 377 Aqueous systems, 206 Ardel, 20, 22... [Pg.577]

Poly f p-oxybenzoyl-co-p-phenylene isophthalate]), 113-114 Poly(2,2 -oxydiethylene adipate), 29 Polyoxymethylene glycol, aqueous, 377 Poly(oxytetramethylene) (PTMO), 53 Poly (p-pheny lene). See also Poly(para-phenylene)s dendronized, 520-521 synthesis of, 491-494 synthesis of water-soluble, 493 Poly(phenylene ether sulfone) chains,... [Pg.597]

Poly(Oxyethyl) Myristyl Ether Poly(Oxyethyl) Pentadecyl Ether Poly(Oxyethyl) Tetradecyl Ether Poly(Oxyethyl) Tridecyl Ether Polyoxymethylene Polyoxymethylene Glycol Polyoxypropylene Glycol Polyoxypropylene Glycol Methyl Ether Polyphosphoric Acid Polypropylene Polypropylene Glycol Polypropylene Glycol Methyl Ether Potassium Chromate Potassium Chromate (VI)... [Pg.78]

Step 3, end-capping of high-molecular-weight polyoxymethylene glycol to provide stable commercial resin. [Pg.1436]

When a DP of approximately 10 is reached, the oligomeric polyoxymethylene glycols are no more soluble, precipitation occurs and further polymerization proceeds in the heterogeneous, crystalline phase. The heterogeneous equilibria are... [Pg.364]

Concentrated solutions containing formaldehyde are unstable, both oxidizing slowly to form formic acid and polymerizing (Gerberich et al. 1980). In the presence of air and moisture, polymerization takes place readily in concentrated solutions at room temperature to form paraformaldehyde, a solid mixture of linear polyoxymethylene glycols containing 90-99% formaldehyde (EPA 1984). [Pg.321]

Paraformal- dehyde Formaldehyde Polymer Polyformaldehyde Polyfooxy- methylene Polyoxymethylene Glycol ... [Pg.253]

POLYOXYMETHYLENE GLYCOLS (50-00-0) Forms explosive mixture with air [flash point gas 185°F/85 C flash point solution (methanol content lowers it) 122°-176°F/ 50°-80°C]. Aqueous solutions (37-55% by weight) are combustible and may explode above their flash points. Aqueous solutions slowly oxidize in air to formic acid. May polymerize... [Pg.998]

DOT) FORMALITH FORMIC ALDEHYDE FORMOL FYDE HOCH IVALON KARSAN LYSOFORM METHANAL METHYL ALDEHYDE METHYLENE GLYCOL METHYLENE OXIDE MORBOCID OXOMETHANE OXYMETHYLENE PARAFORM POLYOXYMETHYLENE GLYCOLS SUPERLYSOFORM... [Pg.146]

CAS 50-00-0 EINECS/ELINCS 200-001-8 UN 1198 (DOT) UN 2209 (DOT) INS240 Synonyms Aldehyde Cl Formalin Formic aldehyde Formol HOCH Methaldehyde Methanal Methyene oxide Methyl aldehyde Methylene glycol Oxymethylene Paraform Polyoxymethylene glycols... [Pg.1842]

Polyoxymethylene glycols. See Formaldehyde Polyoxymethylene homopolymer. See Acetal... [Pg.3536]

Synonyms BFV FA Fannoform Formalin Formalin 40 Formalith Formic aldehyde Formol Fyde HOCH Ivalon Karsan Lysoform Methanal Methyl aldehyde Methylene glycol Methylene oxide Moibicid NC1-C02799 Oxomethane Oxymethylene Paraform Polyoxymethylene glycols RCRA waste number U122 Superlysoform UN 1198 UN 2209. [Pg.51]

Utterback and co-workers [54] determined oligomers of polyoxymethylene glycols and ethers by derivatisation with ammonia then determination by capillary column GC. Okada [55] used temperature programmed GC to determine polymethylene oligomers. High temperature capillary GC has also been used to determine separate Novoloc phenolic and epoxy novolac oligomers [56]. [Pg.183]

Formaldehyde is the most frequently used aldehyde in the production of phenolic resins. At room temperature, it is a pungent, colorless, highly flammable gas. Formaldehyde is highly reactive and commonly conunercialized in aqueous solution stabilized with methanol, where it predominantly forms adducts with the solvent, that is, equilibrium mixtures of methylene glycol, polyoxymethylene glycols and hemiformals of these glycols with methanol (Kowatsch, 2010 Fink, 2005). [Pg.14]

Uttenbach and co-workers [133] characterised and determined formaldehyde oligomers by capillary column GC. The homologous samples of polyoxymethylene glycols and the corresponding monomethyl ethers were derivatised with ammonia prior to GC. [Pg.282]

When aqueous solutions of formaldehyde are evaporated to dryness, a white crystalline solid (m.p. 121-123 C) known as paraformaldehyde is obtained. This comprises polyoxymethylene glycols formed by condensation of methylene glycol (hydrated formaldehyde see Section 8.3.2.) ... [Pg.154]

Synonyms Fomraldehyde polymer Polytbrmaldehyde Polyfboxymcthylene Polyoxymethylene glycol Chemi-... [Pg.635]

To determine formaldehyde oligomers in polyoxymethylene glycols and the corresponding polyoxymethylene ethers Utterback et first derivitivized them with ammonia then determined the oligomers by capillary column gas chromatography. [Pg.37]

See other pages where Polyoxymethylene glycols is mentioned: [Pg.121]    [Pg.377]    [Pg.121]    [Pg.766]    [Pg.342]    [Pg.208]    [Pg.84]    [Pg.677]    [Pg.1848]    [Pg.364]    [Pg.364]    [Pg.55]    [Pg.886]    [Pg.886]    [Pg.998]    [Pg.468]    [Pg.180]    [Pg.1301]    [Pg.646]    [Pg.37]   
See also in sourсe #XX -- [ Pg.305 ]



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