Splice for jointing steel cord strips encased in thermoplastic material

Abstract

A splice is described for jointing thermoplastic strips that include steel cords. In the splice a splice polymer is used that is a mixture of a co-polymer and a base polymer, wherein the co-polymer is a grafted co-polymer, a block co-polymer or a random co-polymer functionalized for enabling adhesion to the steel cords. Particular about the inventive splice is that the amount of co-polymer in the base polymer is such that in a test-till-break of a splice, part of the steel cords fracture in the test while the remaining cords are pulled out of the polymer without breaking. Surprisingly, a splice with such a failure behavior results in a better overall splice strength than a splice wherein a too large amount of co-polymer is added. When too much co-polymer is added all steel cords break in the test which strangely enough leads to a lower overall strength of the splice.