Heat-sealable polyolefins and articles made therefrom

A process for preparing an article comprising the step of heat sealing a first thermoplastic surface to a second thermoplastic surface, wherein the first thermoplastic surface and the second thermoplastic surface comprise a branched polyolefin having a density of about 0.86 to about 0.93 g/mL, having three or more branches of the formula —(CH2CH2)mH wherein m is an integer of one or more, provided that said branched polyolefin has one or both of the following properties:

• said branched polyolefin contains less than 2 methyl groups per 1000 methylene groups and at least 30 total branches per 1000 methylene groups;
• said branched polyolefin contains less than 0.3 branches of the formula —(CH2)5H per 1000 methylene groups;
• and in said branched polyolefin the level of hexyl+branches is at least 80% of the level of ethyl branches, and
• said polyolefin contains less than 2 methyl branches per 1000 methylene groups or less than 0.3 branches of the formula —(CH2)4CH3 per 1000 methylene groups or both.

A process, comprising,

• (a) manufacturing a branched polyolefin by contacting ethylene with a first active catalyst which oligomerizes ethylene to a series of α-olefins, and a second active catalyst which copolymerizes said ethylene and said α-olefins to a branched polyolefin;
• (b) forming said branched polyolefin into an article;
• and
• (c) forming a heat seal with said article wherein at least one surface which is heat-sealed comprises said branched polyolefin.

An article made at least in part from a first thermoplastic surface and a second thermoplastic surface joined together by heat sealing, wherein the first thermoplastic surface and a second thermoplastic surface comprise a branched polyolefin having a density of about 0.86 to about 0.93 g/mL, having three or more branches of the formula —(CH2CH2)mH wherein m is an integer of one or more, provided that said branched polyolefin has one or both of the following properties:

• said branched polyolefin contains less than 2 methyl groups per 1000 methylene groups and at least 30 total branches per 1000 methylene groups;
• said branched polyolefin contains less than 0.3 branches of the formula —(CH2)5H per 1000 methylene groups;
• and
• in said branched polyolefin the level of hexyl+branches is at least 80% of the level of ethyl branches, and said polyolefin contains less than 2 methyl branches per 1000 methylene groups or less than 0.3 branches of the formula —(CH2)4CH3 per 1000 methylene groups or both.