| 摘要 |
A process for the production of a high molecular weight polyurethane-urea polymer, which contains urea-linked N-(hydroxyalkyl) alkylene diamine radicals, one of the nitrogen atoms of each urea bridge being provided by the diamine, includes the step of reacting together (I) an isocyanate-terminated polyurethane polymer formed from (a) a polymeric glycol having a molecular weight of at least 250, such as a polyalkyleneether glycol, polyurethane glycol, polyalkylene-aryleneether glycol, polyalkylenecycloalkyleneether glycol, poly-alkyleneetherpolythioether glycol, polyesteramide glycol and polyester glycols of the formula HO-(B-D-CO-B1-CO-O)n-B-OH wherein B and B1 are hydrocarbon radicals and n is an integer and (b) an organic polyisocyanate such as an organic diisocyanate, and between 0,5 and 1,5 moles per NCO group in (I) of (II), an N-(hydroxyalkyl) alkylene diamine, to produce a polymer characterized by the presence of recurring linkages of the formula <FORM:0883568/IV (a)/1> wherein Z is selected from hydroxyalkyl and hydrogen, at least one Z being hydroxyalkyl, and wherein q is an integer from 2 to 10, inclusive, the relationship of (I) and (II) being such that the recurring linkages of the above formula recur on an average at least once for every 8,000 molecular weight units of the polyurethane-urea polymer. The product can be reacted with an organic polyisocyanate to effect a cure through cross-linking thereof. A list of suitable N-(hydroxy-ethyl, propyl, butyl, amyl and hexylethylene, propylene, butylene, isobutylene, hexylene, octamethylene and decamethylene-diamines is given. The reaction of I and II can be effected by solvent, bulk or emulsion technique. The reaction of (a) and (b) can be effected in the absence of a solvent or in the presence of, for example ketones, tertiary alcohols, esters or aliphatic of cycloaliphatic hydrocarbons. The product (I), if to be chain-extended by emulsion technique, can be emulsified with polyethylene glycol ethers, quaternary ammonium salts, alkali metal salts of high molecular weight acids or amine or alkylol amine salts of long chain alkyl acid sulphate esters, alkyl sulphonic acids or alkyl aryl sulphonic acids. After the chain extension the latex can be coagulated by adding acids or inorganic salts. In Examples (2) a prepolymer is prepared by reacting a dihydric dihydric polyoxyethylene - polyoxypropylenes of M.W. 2000 with tolylene 2,4 and 2,6- diisocyanates in an NCO/OH ratio of 2,0. The product, dissolved in toluene, is emulsified in water and reacted with N-(2-hydroxypropyl) ethylene diamine. The latex obtained is coagulated by freezing and the collected polymer is dried and moulded; (3) the collected polymer of (2) is mixed with carbon black and 3,31-dimethyl-diphenylmethane-4,41-diisocyanate and heated to vulcanize it. Instead of polyissocyanates as vulcanizing agents there can be used tetrachloroquinone, quinone dioxime, paraformaldehyde, organic and inorganic peroxides and low-stage phenolic, melamine or urea-formaldehyde resins. Clay, silica, talc, zinc and magnesium oxides, titanium dioxide and tetralkoxides, plasticizers and organic and inorganic pigments are other suitable compounding agents.
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