NOVELTY - The encapsulant of photovoltaic module (20) comprises two or three nanostructured thermoplastic adjacent layers that consist of: a graft polymer polyamide (5-50 wt.%) comprising a polyolefin backbone and a rest of unsaturated monomer; and polyolefin consisting of polyethylene containing an ethylene homopolymer or a copolymer comprising 50 mol.% of ethylene and comonomers. The graft polyamide is attached to the polyolefin backbone by the rest of unsaturated monomer comprising a function for reaction by a condensation reaction with a polyamide having a terminal amine and/or carboxylic acid.    USE - The encapsulant of photovoltaic module is useful for coating a photovoltaic stack.    ADVANTAGE - The encapsulant has good flame retardant properties and UV resistance, increases the performance of the photovoltaic module, allows the transmission of light waves of the radiation to photovoltaic cells, and avoids risk of corrosion/oxidation to the photovoltaic stacks.    DETAILED DESCRIPTION - The encapsulant of photovoltaic module (20) comprises two or three nanostructured thermoplastic adjacent layers that consist of: a graft polymer polyamide (5-50 wt.%) comprising a polyolefin backbone and a rest of unsaturated monomer; and polyolefin consisting of polyethylene containing a ethylene homopolymer or a copolymer comprising 50 mol.% of ethylene and comonomers. The graft polyamide is attached to the polyolefin backbone by the rest of unsaturated monomer comprising a function for reaction by a condensation reaction with a polyamide having a terminal amine and/or carboxylic acid. The rest of unsaturated monomer (1.3-10) is fixed on the backbone by grafting or copolymerization. The polyolefin backbone and the graft polyamide are selected such that the graft polymer polyamide has a flow temperature of 75-160 degrees C, where the flow temperature is highest temperature from the melting points and glass transition temperatures of the graft polyamide and the polyolefin backbone. A number-average molar mass of graft polyamide is 2000-3000 g.mol-1. The polyamide backbone has melting temperature of 110 degrees C. The encapsulant has a thickness of 200-600 mu m. The thermoplastic adjacent layer has a thickness of 1-1980 mu m An INDEPENDENT CLAIM is included for a photovoltaic module.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic view of a photovoltaic module.    Photovoltaic stack (10)    Photovoltaic module (20)    Upper part (22)    Upper protective layer (24)    Backsheet. (26)