Ethylene/Alpha-Olefin Copolymers for Better Optical and Mechanical Properties and Processability of Film Made Therefrom

A Ziegler-Natta catalyzed ethylene/alpha-olefins copolymer, wherein the copolymer comprises the following properties:

• density of between 0.890 and 0.935 g/cc;
• C4-C10 comonomer content of between 1 and 20 wt %;
• melt index (I2) of between 0.5 and 10 dg/min;
• ratio (Mz/Mw) of z-average molecular weight (Mz) to weight average molecular weight (Mw) of between 3.0 and 10;
• melting point over 124° C. across the density of 0.890 to 0.935 g/cc;
• sporadic long chain branches with J-C α value of less than 5;
• melt strength index, defined as the ratio of storage modulus to loss modulus (G′/G″) at a shear rate of 0.03 s−1, is less than 5;
• weight average molecular weight Mw of less than 200,000 g/mol;
• a fraction soluble below about 30° C. of greater than 12 wt %, determined by CRYSTAF, having a weight average molecular weight Mw of higher than 90,000 g/mol, determined by gel permeation chromatography (GPC);
• a fraction soluble between about 60° C. and 75° C. of less than 35 wt %, determined by CRYSTAF;
• greater than 13.5 wt % of a polymer component having an elution temperature below about 30° C., determined by temperature rising elution fractionation (TREF) analysis;
• greater than 15 wt % of a polymer component having an elution temperature below about 40° C., determined by TREF analysis, and an average high molecular weight of greater than 90,000 g/mol, determined by GPC analysis;
• greater than 10 wt % of a polymer component having an elution temperature range from about 30° C. to 60° C., determined by TREF analysis;
• less than 50 wt % of a polymer component having an elution temperature range from about 60° C. to 94° C., determined by TREF analysis;
• greater than 25 wt % of a polymer component having an elution temperature higher than about 94° C., determined by TREF analysis;
• a substantially constant distribution of short chain branching across its molecular weight distribution (MWD) in each fraction over the elution temperature range from about 30° C. to 94° C., determined by GPC coupled with Fourier Transform Infrared Spectroscopy Detector (GPC-FTIR);
• and
• a reversed distribution of comonomer composition across the molecular weight distribution in the fractions eluted over about 94° C., determined by GPC-FTIR analysis;
• and
• a high molecular weight tail in the fractions over the elution temperature range over about 100° C.