| 摘要 |
Organic esters of the high molecular weight formaldehyde polymer described in Specifications 748,836, 753,299, 766,524 and 766,629, which contain free hydroxy groups are made by interacting the polymer with a carboxylic or substituted carboxylic acid or an anhydride thereof, preferably in the presence of a catalyst. Esterification may be effected by dispersing or dissolving the polymer in a diluent or solvent or by the direct action of anhydride vapours on the solid polymers. The catalyst may be a salt whose cation is an alkali metal and whose anion is the product obtained by removing a hydrogen atom from an acid having a dissociation constant which is less than 1.5X10-4 at 25 DEG C. and/or a basic catalyst. The anhydride may be of acids such as acetic, propionic, butyric, caproic, decanoic, stearic, cyclohexanecarboxylic, benzoic, 4-phenyl benzoic or phthalic, or a mixed anhydride such as acetic propionic anhydride. Catalysts mentioned are pyridine, quinoline, methylethyl pyridine, dimethylaniline, N - phenylmorpholine, di - ethylcyclo - hexylamine, dimethylcyclohexylamine, trimethyl and triethylamines, the lithium, sodium, potassium, rubidium or cesium salt of formic, stearic, carbonic, benzoic, acetic or sulphurous acid, or disodium phosphate. The diluent or solvent may be n-heptane, hexane, cyclohexane, toluene, benzene or xylene. The esterified polymers may be treated with an antioxidant stabilizer such as a phenolic compound, e.g. beta-conidendrol, a secondary or tertiary amine, e.g. di - beta - naphthyl - p - phenylenediamine, hydrazines, ureas, or thioureas. The esterified polymer may be made into films, fibres or filaments.
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