Method for improving the grip of a tyre on a snowy and/or icy road, and a winter tyre

摘要

A method for improving tyre grip on snowy and/or icy roads includes forming a tread band with a base elastomeric material comprising at least 70 wt % of a polymer mixture including between 20 wt % and 60 wt % of at least one styrene/1,3-butadiene copolymer and between 40 wt % and 80 wt % of at least one 1,3-butadiene homopolymer. The at least one styrene/1,3-butadiene copolymer comprises styrene units and vinyl units. The at least one 1,3-butadiene homopolymer comprises vinyl units. The glass transition temperature of the at least one styrene/1,3-butadiene copolymer is at least 30° C. higher than that of the at least one 1,3-butadiene homopolymer. A mixture of the at least one styrene/1,3-butadiene copolymer with the at least one 1,3-butadiene homopolymer shows a single glass transition peak having a maximum value corresponding to a temperature greater than or equal to −70° C. and less than or equal to −45° C.