NOVELTY - Adhesive composition, preferably permanent-barrier comprises (i) block copolymers and/or its mixtures, and (ii) at least one adhesive resin.    USE - The adhesive composition is useful as a barrier composition for preventing a diffusion of permeant and for encapsulating an electronic arrangement and an optoelectronic arrangement, where the adhesive composition includes a pressure-sensitive adhesive composition or a melt adhesive composition (all claimed), and the optoelectronics are electrophoretic or electrochromic assemblies or displays, organic or polymeric light emitting diodes in display and display devices or as illumination, electroluminescent, light-emitting electrochemical cells, organic solar cells, preferably solar cells, polymer or dye, inorganic solar cells, thin film solar cells, organic field-effect transistors, organic integrated circuits, organic optical amplifiers, organic laser diodes, or inorganic-based radio-frequency identification-transponder.    ADVANTAGE - The adhesive composition exhibits improved rigidity or flexibility.    DETAILED DESCRIPTION - Adhesive composition, preferably as permanent-barrier comprises (i) block copolymers and/or its mixtures of formula A-B-A, (AB)n, (AB)nX or (A-B-A)nX, where a portion of the A-blocks is sulfonated and optionally two block copolymers of the form A-B act as an additive component, and (ii) at least one adhesive resin.    X = a residue of coupling agent;    A = a polymer block made of aromatic vinyl groups;    B = a polymer block of an alkene or diene; and    n = 2-10.    INDEPENDENT CLAIMS are included for:    (1) preparing the adhesive composition, comprising providing the block copolymers and/or its mixtures, and mixing the adhesive resin; and    (2) a flat adhesive agent comprising the adhesive composition, comprising a surface element and an adhesive tape, where the adhesive tape comprises a support and the adhesive composition coated on at least one side of the carrier, and the adhesive composition of the adhesive agent is substantially dried.