Low density oriented polymer composition with inert inorganic filler

Abstract

An article of manufacture comprising a polymer composition, having 30 wt % or more and 95 wt % or less inert inorganic filler, that is oriented by the steps of conditioning the polymer composition to a drawing temperature of at least 15° C. and approximately 40° C. below a softening temperature of the polymer composition; and drawing the polymer composition though a drawing die at a drawing rate of at least 0.25 m/min and with a nominal draw ratio of 1.25 or more and 8 or less to produce the article of manufacture made of the oriented polymer composition.

1 . An article of manufacture, comprising:
 a polymer composition, having 30 wt % or more and 95 wt % or less inert inorganic filler, that is oriented by the steps of conditioning the polymer composition to a drawing temperature of at least 15° C. and approximately 40° C. below a softening temperature of the polymer composition; and drawing the polymer composition though a drawing die at a drawing rate of at least 0.25 m/min and with a nominal draw ratio of 1.25 or more and 8 or less to produce the article of manufacture made of the oriented polymer composition, the article of manufacture having:
 (a) a density of less than 0.8 g/cm 3  according to ASTM method 792-00; 
 (b) a flexural modulus of 1.4 GPa (200,000 psi) or more according to ASTM method D-790-03; 
 (c) a cross-sectional dimension defined according to a cross section of the article, with the cross section having a centroid and a perimeter that defines a shape for the cross section, with all cross sectional dimensions greater than 1.5 mm; 
 (d) a delamination force value greater than 44.5 N (10 lbf); and 
 (e) at least 30 vol % void volume proximate to the inert inorganic filler in the oriented polymer composition. 
   
     
     
         2 . The article of  claim 1 , wherein the inert inorganic filler is selected from a group consisting of talc, calcium carbonate, clay and fly ash. 
     
     
         3 . The article of  claim 1 , wherein the oriented polymer composition is comprised of at least one polymer selected from the group consisting of polypropylene-based polymers, polyethylene-based polymers, polyvinyl chloride, polyesters and polyester-based polymers. 
     
     
         4 . The article of  claim 1 , wherein the oriented polymer composition further comprises less than or equal to 3 weight-percent of a blowing agent. 
     
     
         5 . The article of  claim 1 , comprising 40 percent by weight or more of the inert inorganic filler. 
     
     
         6 . The article of  claim 1 , wherein the polymer composition is comprised of a semi-crystalline polymer. 
     
     
         7 . The article of  claim 1 , comprising 40 percent by weight or more of the inert inorganic filler. 
     
     
         8 . The article of  claim 1 , wherein the polymer composition is comprised of a semi-crystalline polymer. 
     
     
         9 . The article of  claim 1 , wherein the inert inorganic filler has a density of at least 2 g/cm 3 .