Patent ID: 9617399
Date: 2017-04-11
CPC Classifications: B29C,B29K,C08J,C08K,C08L

Claim:
1. An improvement in a method of forming a polyolefin-based article that includes (a) incorporating into a polyolefin formulation a filler that is capable of being excited by a high frequency electromagnetic field; (b) forming a substrate from the polyolefin formulation, the substrate having at least one surface; and (c) subjecting the surface of the polyolefin substrate to the high frequency electromagnetic field under conditions such that the substrate is welded to a second surface of the polyolefin substrate or to a surface of a second polyolefin substrate to form a polyolefin-based article; wherein the improvement comprises (1) including in the polyolefin formulation a zeolite that is ion exchanged with sodium, calcium, or potassium, in an amount of at least 5 weight percent based on weight of the polyolefin formulation; and (2) employing as a base polymer in the polyolefin formulation a polyolefin selected from the group consisting of (a) a homogeneously branched, linear or substantially linear ethylene/α-olefin copolymer having a density from 0.865 to 0.905 grams per cubic centimeter and a melt index, measured at 190° C. at 2.16 kilograms, from 0.5 to 30 grams per 10 minutes; (b) a homogeneously branched propylene/α-olefin copolymer having a density from 0.863 to 0.885 grams per cubic centimeter and a melt flow rate, measured at 230° C. at 2.16 kilograms, from 2 to 30 grams per 10 minutes; (c) a combination thereof; provided that the base polymer has a melting temperature below 100° C.; and further provided that the polyolefin substrate exhibits as properties a cohesive welding failure and a weld strength for a 10 mil (0.254 millimeter) thickness that is greater than 7 pounds per inch (1.23 Newtons per millimeter) at a welding time of less than or equal to 6 seconds, to form a polyolefin-based article.