FIELD: production of films weldable by heat. SUBSTANCE: composition comprises, %: linear low density polyethylene, 30-60, crystalline copolymer of propylene and α-olefin, 40-70. Melt index of said linear polyethylene is 0.1-15 g/10 min. Mentioned above copolymer comprises 8-20 % of α-olefin being chosen of ethylene, C4-C8-α-olefin or mixture thereof. Composition has temperature of initial stage of welding being 85-110 C. Desired composition is prepared by copolymerziation of α-olefins which takes place in the presence of catalyst. Catalyst comprises titanium compound on active magnesium dihalide and alkyl aluminium, atomic ratio of aluminium and titanium being 1-1000. The process is carried out in at least two stages, at the first stage ethylene is affected by copolymerization with C3-C12-α-olefin. At the consequent stages copolymerization of propylene with C4-C8-α-olefin is carried out, the process takes place in the presence of catalyst. EFFECT: improved quality. 11 cl, 3 tbl
