| 摘要 |
An elastomeric filament or film is made of a linear segmented urea/urethane/ether, ester or ether-ester polymer having an inherent viscosity of at least 3.0 when dissolved in 60% phenol and 40% tetrachloroethane and containing 2-9% of urea segments each containing one or more repeating units (1) -A-NH-CONH-D-NH-CO-NH- and/or (2) -ANHCONH-, where A is the residue of a functionally aliphatic di-isocyanate, and D the residue of a functionally aliphatic diamine NH2-D-NH2 the NH2 groups of which are not sterically hindered, A and D being such that a polyurea consisting solely of repeating units (1) and having a M.W. >104 would have a M.P. of at least 200 DEG C., each of said urea segments being linked at the A end to the NH of a urethane linkage, the -O- of which is bonded to the residue P of a polyether, polyester or polyether-ester and at the -NH- end to the A of a urethane linkage -ANHCO-O, the -O- of which is attached to another P residue. The polyethers, polyesters or polyether-esters used in making the polymers of the invention have the formula HO-P-OH, a molecular weight of 600-12,000 and a melting point below 50 DEG C. They may be replaced by an oligomer of up to 11 P residues linked by urethane groups of formula -O-CO-NHANH-. The segmented linear polymers may be formed in a solution suitable for spinning or casting by forming a macrodiisocyanate from the polyether, polyester or polyether-ester and a diisocyanate, in a suitable solvent, adding water and/or the diamine and allowing reaction until the polymer in solution has an inherent viscosity of at least 2. A small proportion of di-secondary diamine may be used with the di-primary diamine. After formation of the macrodiisocyanate, some or all of the unreacted diisocyanate may be removed (Specification 1,118,736). In the second stage of the process it is advantageous to employ a temperature of 55 DEG C. or higher (Specification 1,118,734). The spinning or coating solutions may be stabilized by addition of an organic acid anhydride or halide (Specification 1,118,735). Stabilizers for the filaments can also be added to the solution before spinning (Specification 1,118,736). The co-polyethers (Specification 1,118,602) may be used in making the polymers of this invention. Many other suitable polyols are mentioned. The di-isocyanates may be sterically hindered or not. Preferred starting materials used in the examples are: Polyethers.-Copolymers of tetrahydrofurane and 8-oxabicyclo-[4.3.0]-nonane; polytetramethylene oxide. Diisocyanates.-Hexamethylene diisocyanate; 1,4 - cyclohexane bis - (methylisocyanate); p-xylylene diisocyanate. Diamines.-Hexamethylene diamine; m- or p - xylylene diamine; 1,4 - cyclohexane bis-(methylamine); ethylene diamine; 4-methylheptane-1,7-diamine. The preferred solvent is N,N-dimethylacetamide.
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