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Copolyetheramides with a block structure for technical applications, with good flexibility at low temperature and with a viscosity in the molten state of at least 50 on the xs
Copolyetheramides with a block structure for technical applications, with good flexibility at low temperature and with a viscosity in the molten state of at least 50 on the xs
Novel block copolyetheramides which are homogeneous and flexible at low temperatures and have melting or softening points of at least 170 DEG C., glass transition temperatures of at most -5 DEG C. and viscosities in the molten state of at least 500 poises, are facilely prepared by copolymerizing (I) admixture of a lactam having from 4 to 12 carbon atoms with a solution of a salt of a fatty acid dimer and a polyoxyalkylenediamine in a solvent medium comprising (i) a mixture of water and an aliphatic alcohol having less than 5 carbon atoms, (ii) a water/alcohol/lactam mixture, (iii) a lactam in molten state or (iv) a water/lactam mixture wherein the lactam is water soluble, the stoichiometry of said salt being adjusted such that the pH thereof is within +/-0.05 pH units of its equivalence point and (II) a minor amount of a strong inorganic oxyacid or a strong organic oxyacid other than a carboxylic acid.
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