POLYURETHANE COMPOSITION COMPRISING A FILLER CONSISTING OF RUBBER CRUMBS AND USED FOR PRODUCING LOW-MODULE OIL- AND PETROL-RESISTANT ELASTOMERS

摘要

The present invention relates to polyurethane compositions used for producing low-module oil- and petrol-resistant materials which have a reduced hardness (10 to 30 specific units in terms of Shore A hardness) and which can be used for coating ink rollers in polygraphic applications, for producing petroleum-product-resistant cladding and coating materials as well as in the industry of composite materials for various purposes. In order to improve the deformation and resistance characteristics of the elastomers while maintaining their oil- and petrol-resistance as well as their low elasticity module and hardness values, the composition includes a mixture of the following complex elements: oligoethertriol, oligoetherdiol with molecular weights of 2000, 2,4-toluylendiisocyanate and rubber crumbs having a fraction of 160-500 mu m, wherein the molar ratio between the oligoethertriol, the oligoetherdiol and the 2,4-toluylendiisocyanate is 0.925 : 0.075 : 1.5, while the part by weight of rubber crumbs ranges from 10 to 20 %. The elastomers thus obtained have a tensile strength of 1.5 to 2.9 MPa, an elasticity module upon a 100 % deformation of 0.32 to 0.85 MPa, an elongation at break of 950 to 1109 %, a tear resistance of 7.7 to 18.5 N/mm, a Shore A hardness of 10 to 30 specific units and a high oil- and petrol-resistance.