Thermoplastic polymer composition and method for making films from the same

A method for producing a film, the method comprising the steps of:

• (a) providing an apparatus comprising:
• (i) a die having an annular die orifice adapted to extrude a tube;
• (ii) a means for blowing pressurized fluid into the tube exiting the annular die orifice;
• and
• (iii) a means for drawing and collecting the tube;
• (b) providing a thermoplastic polymer composition comprising (i) a polyethylene polymer composition having a melt relaxation index of 2 or greater;
• and (ii) a salt of bicyclo[2.2.1]heptane-2,3-dicarboxylic acid;
• (c) heating the thermoplastic polymer composition to a temperature sufficient to melt the thermoplastic polymer composition so that it may be extruded through the die;
• (d) extruding a molten thermoplastic polymer composition through the annular die orifice to form a tube exiting the annular die orifice in a first direction, the tube having a diameter and a length;
• (e) blowing a pressurized fluid into the tube under sufficient pressure to inflate the tube and increase its diameter while simultaneously drawing the tube in the first direction to increase its length, thereby producing a film;
• (f) allowing the film to cool to a temperature at which the thermoplastic polymer composition solidifies;
• and
• (g) collecting the film.