Multilayer films and methods of making the same

A multilayer film comprising a plurality of layers, the plurality of layers comprising an ethylene copolymer layer comprising 100 wt % of a first ethylene copolymer, based on total weight of polymer in the ethylene copolymer layer;

• wherein the first ethylene copolymer comprises at least one of the following:
• (a) a low crystalline polymer comprising greater than or equal to about 70 wt % units derived from ethylene, less than or equal to about 30 wt % units derived from propylene, and less than about 5 wt % of units derived from C4-C20 α-olefins, based on total weight of the polymer, and having the following properties:
• (i) crystallinity derived from ethylene;
• (ii) a heat of fusion of about 20 to about 85 J/g;
• (iii) a polydispersity index (Mw/Mn) of less than about 2.5;
• (iv) a reactivity ratio of about 0.5 to about 1.5;
• (v) a proportion of inversely inserted propylene units based on 2, 1 insertion of propylene monomer in all propylene insertions, as measured by 13C NMR of less than 0.5 wt %;
• and (vi) a branching index greater than about 0.5;
• wherein the polymer is prepared in a single reactor;
• (b) a low crystalline polymer blend composition, comprising:
• (i) from 65 wt % to 90 wt % based on the total weight of the blend of an ethylene α-olefin elastomer having either no crystallinity or crystallinity derived from ethylene, having 70 wt % or more units derived from ethylene;
• and (ii) from 10 wt % to 35 wt % based on the total weight of the blend of a propylene polymer having from 40 wt % to 90 wt % units derived from propylene, including isotactically arranged propylene derived sequences, and 10 wt % or more units derived from ethylene;
• wherein the ethylene α-olefin elastomer and the propylene polymer are prepared in separate reactors arranged in parallel configuration;
• and
• (c) an ethylene-propylene rubber;
• wherein the multilayer film has at least one of the following properties:
• (i) a tear resistance of at least about 25% higher in each of a Machine Direction (MD) and a Transverse Direction (TD);
• and (ii) a dart impact of at least about 25% higher, compared to that of a film free of the first ethylene copolymer, but is otherwise identical in terms of film structure, layer compositions and overall film thickness.

A multilayer film comprising a first layer, a second layer, and a third layer between and in contact with each of the first layer and the second layer, wherein the third layer comprises 100 wt % of a first ethylene copolymer, based on total weight of polymer in the third layer;

• wherein the first ethylene copolymer is a propylene-based elastomer, having at least about 60 wt % propylene-derived units and about 3 to about 25 wt % ethylene-derived units, based on total weight of the propylene-based elastomer, and a heat of fusion of less than about 80 J/g;
• wherein the multilayer film has at least one of the following properties:
• (i) a tear resistance of at least about 6% higher in the Machine Direction (MD);
• (ii) a tear resistance of at least about 12% higher in the Transverse Direction (TD);
• and (iii) a dart impact of at least about 12% higher, compared to that of a film free of the first ethylene copolymer, but is otherwise identical in terms of film structure, layers' compositions and the film's overall thickness, and
• wherein at least one of the first layer and the second layer comprises at least about 80 wt % of a polyethylene derived from ethylene and one or more C3 to C20 α-olefin comonomers, based on total weight of polymer in the layer, wherein the polyethylene has a density of from about 0.900 to about 0.960 g/cm3, a melt index (MI), I2.16, of from about 0.1 to about 15 g/10 min, a polydispersity index (Mw/Mn) of from about 1.5 to about 5.5, and a melt index ratio (MIR), I21.6/I2.16, of from about 10 to about 100 and an LDPE.