Compatible polymer blends useful as melt adhesives

Claim 2

A compatible polymer blend comprising a low density ethylene polymer, a copolymer of butene-1 and from about 1.5 to about 20 weight percent of an olefin selected from the group consisting of ethylene and propylene, a hydrocarbon tackifier and a low molecular weight polymer selected from the group consisting of a low molecular weight liquid polybutene, an amorphous polypropylene and mixtures thereof.

Claim 3

The polymer blend of claim 1 wherein said copolymer is a copolymer of butene-1 and ethylene.

Claim 4

The polymer blend of claim 2 wherein said low molecular weight polymer is a low molecular weight liquid polybutene.

Claim 5

The polymer blend of claim 2 wherein said low molecular weight polymer is an amorphous polypropylene.

Claim 6

The polymer blend of claim 1 wherein said amorphous polypropylene is obtained as a byproduct during the production of crystalline polypropylene.

Claim 7

The polymer blend of claim 1 wherein said amorphous polypropylene is obtained as a direct product of the polymerization of propylene without the formation of crystalline polypropylene.

Claim 8

The polymer blend of claim 2 wherein said low molecular weight polymer is a mixture of a low molecular weight liquid polybutene and an amorphous polypropylene.

Claim 9

The polymer blend of claim 7 wherein said mixture contains from about 97.5 to about 2.5 weight percent of amorphous polypropylene.

Claim 10

The polymer blend of claim 7 wherein said mixture contains from about 75 to about 40 weight percent of amorphous polypropylene.

Claim 11

The polymer blend of claim 2 wherein said low density ethylene polymer has a density of about 0.88 to about 0.94 and a melt index in the range of about 3 to about 5000 grams/10 minutes.

Claim 12

The polymer blend of claim 2 wherein said low density ethylene polymer has a density of about 0.88 to about 0.93 and a melt index of about 20 to about 500 grams/10 minutes.

Claim 13

The polymer blend of claim 2 wherein said butene-1 copolymer has a melt index in the range of about 0.3 to about 2000 grams/10 minutes.

Claim 14

The polymer blend of claim 2 wherein said butene-1 copolymer has a melt index in the range of about 3.0 to about 2000 grams/10 minutes.

Claim 15

The polymer blend of claim 2 wherein said hydrocarbon tackifier has a ring and ball softening point in the range of about 10° to about 150° C.

Claim 16

The polymer blend of claim 2 wherein said hydrocarbon tackifier has a ring and ball softening point in the range of about 10° to about 140° C.

Claim 17

The polymer blend of claim 2 wherein said low molecular weight polymer is a low molecular weight liquid polybutene having a molecular weight from about 500 to about 5000.

Claim 18

The polymer blend of claim 2 wherein said low molecular weight polymer is a low molecular weight liquid polybutene having a molecular weight from about 1300 to about 3000.

Claim 19

The polymer blend of claim 2 wherein said low molecular weight polymer is an amorphous polypropylene having a crystallinity of les than about 10 weight percent and a molecular weight in the range of about 300 to about 20,000.

Claim 20

The polymer blend of claim 2 wherein said low molecular weight polymer is an amorphous polypropylene having a crystallinity of less than about five weight percent and a molecular weight in the range of about 1000 to about 15,000.

Claim 21

The polymer blend of claim 2 wherein said low density ethylene polymer has a density of about 0.88 to about 0.94 and a melt index of about 3 to about 5000 grams/10 minutes, said butene-1 copolymer has a melt index in the range of about 0.3 to about 2000 grams/10 minutes, said hydrocarbon tackifier has a ring and ball softening point in the range of about 10° to about 150° C. and said low molecular weight polymer is a low molecular weight liquid polybutene having a molecular weight from about 500 to about 5000.

Claim 22

The polymer blend of claim 2 wherein said low density ethylene polymer has a density of about 0.88 to about 0.93 and a melt index of about 20 to about 500 grams/10 minutes, said butene-1 copolymer has a melt index in the range of 3.0 to about 2000 grams/10 minutes, said hydrocarbon tackifier has a ring and ball softening point in the range of about 10° to about 140° C. and said low molecular weight polymer is a low molecular weight liquid polybutene having a molecular weight from about 1300 to 3000.

Claim 23

The polymer blend of claim 2 wherein said low density ethylene polymer has a density of about 0.88 to about 0.94 and a melt index in the range of about 3 to about 5000 grams/10 minutes, said butene-1 copolymer has a melt index in the range of about 0.3 to about 2000 grams/10 minutes, said hydrocarbon tackifier has a ring and ball softening point in the range of about 10° to about 150° C. and said low molecular weight polymer is an amorphous polypropylene having a crysytallinity of less than about 10 weight percent and a molecular weight in the range of about 300 to about 20,000.

Claim 24

The polymer blend of claim 2 wherein said low density ethylene polymer has a density of about 0.88 to about 0.93 and a melt index in the range of about 20 to about 500 grams/10 minutes, said butene-1 copolymer has a melt index in the range of about 3.0 to about 2000 grams/10 minutes, said hydrocarbon tackifier has a ring and ball softening point in the range of about 10° to about 140° C. and said low molecular weight polymer is an amorphous polypropylene having a crystallinity of less than about five weight percent and a molecular weight in the range of about 1000 to about 15,000.

Claim 25

The polymer blend of claim 2 wherein said components are present in the following amounts: ______________________________________ Weight Percent ______________________________________ Low Density Ethylene Polymer 2.5-40 Butene-1 Copolymer 5-60 Hydrocarbon Tackifier 5-40 Low Molecular Weight Liquid Polybutene or 5-60 Amorphous Polypropylene 5-87.5 ______________________________________

Claim 26

The polymer blend of claim 2 wherein said components are present in the following amounts: ______________________________________ Weight Percent ______________________________________ Low Density Ethylene Polymer 5-30 Butene-1 Copolymer 10-50 Hydrocarbon Tackifier 10-35 Low Molecular Weight Liquid Polybutene or 10-40 Amorphous Polypropylene 10-75 ______________________________________

Claim 27

The polymer blend of claim 24 wherein the weight ratio of low density ethylene polymer to the butene-1 copolymer is in the range of about 9:1 to about 1:9.

Claim 28

The polymer blend of claim 25 wherein the weight ratio of low density ethylene polymer to the butene-1 copolymer is in the range of about 1:3 to about 3:1.

Claim 29

The polymer blend of claim 2 wherein a paraffin or microcrystalline wax is also present.

Claim 30

The polymer blend of claim 2 wherein an antioxidant is also present.

Claim 31

The polymer blend of claim 2 wherein a paraffin wax or microcrystalline wax and an antioxidant is also present.