TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The adhesion promoting agent is a compound of formula (X)3-p(Me)p-Si-R-Y1 (III). The ratio of moles of Si-H groups contained in the cross-linking agent relative to moles of alkenyl groups contained in the base compound (moles of Si-H group/moles of alkenyl group) is 1.2-5.X=methoxy, ethoxy, or 2-methoxyethoxy;Me=methyl;R=ethylene or propylene;Y1=amino, vinyl, methacrylyl, isocyanate, mercapto, ureido, or epoxy;p=0 or 1. EXAMPLE - An adhesive composition comprising: SIFEL2660 (RTM: an olefinic poly(fluoroalkoxy)silane base compound having a formula H2C=CH-Si(CH3)2-(CF(CF3)-CF2O)n-Si(CH3)2-CH=CH2 (where n is 500)) (50 wt.%); cross-linking agent (a polysiloxane of formula H-Si(CH3)2-O-(Si(CH3)2-O)x-(SiH(CH3)-O)y-Si(CH3)2-H (where x+y is 20)) (3 wt.%); platinum black (catalyst) (4 ppm); A-187 (RTM: adhesion promoting agent) (40 wt.%); tetravinyldimethylsiloxane (reaction inhibitor) ( less than or equal to 1 wt.%); and fillers (7 wt.%), having ratio of moles of Si-H groups/moles of alkenyl groups of 1.2; was prepared by kneading the base compound and the cross-linking agent, further kneading with the filler and the adhesion promoting agent; the reaction catalyst and the reaction inhibitor were added; and the components were allowed to disperse to obtain the adhesive for the membrane-electrode assembly of the fuel cell. A fuel cell (test) was prepared using the membrane-electrode assembly comprising the adhesive. The fuel cell comprising the conventional adhesive was used as a (comparative) fuel cell. Both fuel cells were evaluated for the adhesive layer bond durability (for bonding of a gas diffusion layer with the solid polymer electrolyte membrane) after electric power generation at electric current density of 1 A/cm2, for 3000 hours. It was observed that after the test: the gas diffusion layer and the solid polymer electrolyte membrane remained joined in the (test) fuel cell, whereas the layers were separated in the (comparative) fuel cell. The results showed that the (test) fuel cell employing the (test) adhesive layer had very high bond durability than the fuel cell comprising the conventional adhesive.