| 摘要 |
Elastomeric polyurethane filamentary materials are obtained by p reacting a polyacetal having at least two terminal hydroxyl groups in the molecule and a molecular weight of from 500 to 5,000 with an organic polyisocyanate in a first step to prepare an isocyanate-terminated intermediate reaction product and extruding said product into a coagulating bath comprising an organic polyamine in solution or liquid form thus causing the extruded streams to set into the form of solid filaments. The polyacetals may be prepared by reacting a polyhydric alcohol such as butane-1,4-diol, hexane-1,6-diol, butane-1,4-di-(b -hydroxyethyl)-ether, dihydroxy ethyl ether, diethylene glycol or triethylene glycol optionally mixed with trimethylol propane or glycerine with an aldehyde such as formaldehyde, paraformaldehyde, acetaldehyde, crotonaldehyde, or chloral. The polyisocyanates may be toluylene-2,4- and 2,6-diisocyanates, diphenylmethane-4,41-diisocyanate, phenylene-1,4-diisocyanate, 4,41-diisocyanatodiphenyl dimethylmethane, hexamethylene diisocyanate, cyclohexane-1,4- and furfurylidene diisocyanate. Preferably the reaction is carried out at a temperature of 70 DEG and 130 DEG C. in a solvent such as dioxane, tetrahydrofuran, dimethyl formamide, dimethyl acetamide, methyl ethyl ketone, glycol monoethyl ester acetate, methylene chloride or chloroform. The reaction may be modified by the addition of reactive hydrazines, polyhydric alcohols, polyamines and amino alcohols, of which the following are specified:-hydrazine hydrate, methyl hydrazine, dimethyl hydrazine, ethylene glycol, propylene glycol, butane-1,4-diol, hexane-1,6-diol, trimethylol ethane, trimethylol propane, hydroxyalkylated glycols, 1,4-bis-hydroxyethoxy butane, bis-hydroxy ethyl hydroquinone, N,N1-bis-hydroxy ethyl piperazine, ethylene diamine, diethylene triamine, N-methyl dipropylene triamine, piperazine, bis-(g -amino-propyl)-piperazine, di-(g -amino-propoxy)-butane, 4,41-diaminodiphenyl-methane, amino propanol and aminoethanol. Catalysts such as trimethylamine, triethylene diamine, dimethyl aniline, hexahydrodimethyl aniline, alkyl morpholines and dialkyl piperazines may also be added to the spinning bath. Specification 798,209 is referred to.
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