| 摘要 |
FIELD: chemistry. ^ SUBSTANCE: the method relates to cast elastomers used as oscillation dampening elements to dampen the oscillations of any kinds of machinery, more specifically in construction of train-ferries, ship building and engineering, etc. The said cast elastomers are produced from the (A) NCO-prepolymer of the high-melting polyisocyanate taken from the group consisting of 1,5-naphthalene diisocyanate (NDI), para-phenylene diisocyanate (PPDI) and 3,3'-dimethyl-4,4'-bi-phenyl diisocyanate (TODI); and (b) a mixture of polyols of (b1) 50-85 mol-% in regard to (b1) and (b2), -hydro-ë-hydroxy-poly-(oxytetramethylene) with the molecular weight ranging from 500 to 5000 g/mol and hydroxy functionality of 2,0; (b2) 15-50 mol-% in regard to b1) and b2), -hydro-ë-hydroxy-poly-(oxypropylene-1,2) and/or -hydro-ë-hydroxy-poly-(oxypropylene-1,2-so-oxyethylene) with the molecular weight ranging from 900 to 4000 g/mol and hydroxy functionality ranging from 1,9 to 2,7, whereas the hydroxyl value of the polyol mixture of (b1) and (b2) ranges from 36 to 90 mg KOH/g; and (B) at least one chain extender taken from a group of aliphatic diols with two hydroxil groups (preferably where they are primary groups) and the average molecular weight ranging from 62 to 202 g/mol, trifunctional polyols, polyols (b1), polyols (b2), water and their mixtures, as well as aromatic diamines; (C) if required, additive agents and supplements, where the molecaular ratio of the NCO-groups to the active groups of all components ranges from 1,04 to 1,25 and the ratio of the storage modulus G' measured at -30C and the same parameter measured at 110C (in accordance with DIN EN ISO 6721-1) ranges from 0,8 to 2. Described is a method of producing the said cast elastomers. ^ EFFECT: production of the polyurethane materials with improved properties related to the temperature dependence of material properties: storage modulus G', loss-angle tangent tan and loss modulus G'' while retaining all other good properties. ^ 2 cl, 12 ex, 3 tbl |
