Grafted thermoplastic compositions and fabricated articles therefrom

A grafted blend composition comprising

• (A) a blend of;
• 1) one or more linear or substantially linear ethylene homopolymers or interpolymers and one or more branched ethylene homopolymers or interpolymers;
• 2) one or more linear or substantially linear ethylene homopolymers or interpolymers and one or more substantially random interpolymers;
• or
• 3) one or more linear or substantially linear ethylene homopolymers or interpolymers, one or more branched ethylene homopolymers or interpolymers and one or more substantially random interpolymers;
• and
• (B) one or more coupling agents;
• and wherein said grafted blend composition has
• a) a melt strength, greater than about 8 cN;
• b) a melt elongation of 20 mm/s or greater;
• c) a flexural modulus of 80,000 psi or greater;
• and
• d) a gel content which is 50 percent or less, as determined by insolubility of the gels in boiling xylene when tested according to ASTM D-2765A-84.

A grafted blend composition which has a melt index, I2, of about 0.05 to about 10 g/10 min comprising;

• A) from 55 to 90 wt percent (based on the combined weights of component A and B) of a linear or substantially linear ethylene homopolymer or interpolymer, having a density of greater than 0.9450 g/cm3;
• B) from 10 to 45 wt percent (based on the combined weights of component A and B) of a branched ethylene homopolymer or interpolymer having a melt strength of greater than 5 cN;
• and
• C) from 0.005 wt percent to about 0.2 wt % (based on the combined weights of A and B) of a coupling agent;
• and
• D) wherein the melt strength of said grafted blend is greater than 5 cN.

A grafted blend composition comprising,

• (A) one or more olefinic polymers other than polypropylene;
• (B) one or more propylene homopolymers or interpolymers;
• and
• (C) at least one coupling agent;
• and wherein said grafted blend has
• 1) a gel content which is 50 percent or less, as determined by insolubility of the gels in boiling xylene when tested according to ASTM D-2765A-84;
• 2) a melt elongation greater than or equal to about 20 mm/s,
• 3) a melt strength greater than about 5 cN;
• and
• 4) a flexural modulus of 50,000 psi or greater.

A process for preparing grafted blend compositions comprising a coupling agent in solid form and a polymer or polymer blend composition, said process comprising;

• 1) mixing said polymer or polymer blend with a tackifier;
• 2) tumble blending the mixture from step 1 with said coupling agent;
• and
• 3) extruding the resulting mixture at a temperature at which the coupling agent is activated.

A process for preparing grafted blend composition comprising a coupling agent in liquid form and a polymer or polymer blend composition, said process comprising;

• 1) mixing said coupling agent with a tackifier, and
• 2) tumble blending the mixture from step 1 with said polymer or polymer blend composition;
• and
• 3) extruding the resulting mixture at a temperature at which the coupling agent is activated.

A process for preparing grafted blend composition comprising a coupling agent and resin comprising a polymer blend composition, said process comprising;

• 1) preparing a mixture of the coupling agent;
• and a resin comprising one of the components of said polymer blend, and extruding the resulting mixture at a temperature at which the coupling agent is not activated;
• 2) adding the remaining component(s) of said polymer blend composition, other than that used in step (1), to the mixture from step (1), in an amount required to give the final desired concentration of coupling agent (based on the weight of the final grafted blend composition);
• and
• 3) extruding the mixture from step 3 at a temperature at which the coupling agent is activated.