Polymer processing additive, compositions, and methods
A poly(oxyalkylene) polymer and a metal salt of a carboxylic acid, sulfonic acid, or alkylsulfate, in combination are useful as a polymer processing additive synergist. Polymer processing additive compositions, homogeneously catalyzed olefin compositions, and other extrudable polymer compositions including a poly(oxyalkylene) polymer and a metal salt of a carboxylic acid, sulfonic acid, or alkylsulfate are disclosed. Methods of reducing melt defects during the extrusion of a thermoplastic polymer, which may be a homogeneously catalyzed polyolefin, are also disclosed.
1. A composition comprising:
a polyolefin;
a polymer processing additive selected from the group consisting of a fluoropolymer and a silicone-containing polymer; and
a polymer processing additive synergist comprising a polyethylene glycol and a metal salt selected from the group consisting of a metal salt of an aliphatic carboxylic acid, a metal salt of an aliphatic sulfonic acid, and a metal salt of an alkylsulfate, wherein the polyethylene glycol is present in an amount of at least 85% by weight, based on the total weight of the polymer processing additive synergist, and wherein the metal salt is a sodium, potassium, aluminum, or barium salt.
2. The composition of claim 1 , wherein the polymer processing additive synergist comprising the polyethylene glycol and the metal salt has higher thermal stability than the polyethylene glycol alone.
3. The composition of claim 1 , wherein the metal salt is the metal salt of an aliphatic carboxylic acid or the metal salt of an aliphatic sulfonic acid.
4. The composition of claim 3 , wherein the metal salt is the metal salt of an aliphatic carboxylic acid, and wherein the aliphatic carboxylic acid is other than stearic acid.
5. The composition of claim 1 , further comprising an at least one of an antioxidant, a metal oxide, or a hindered amine light stabilizer.
6. The composition of claim 1 , wherein the metal salt is present in an amount of at least 5% by weight, based on the total weight of the polymer processing additive synergist.
7. The composition of claim 1 , wherein the polyolefin is a linear low density polyethylene.
8. The composition of claim 1 , wherein the polyolefin is made by homogeneous catalysis with a metallocene catalyst.
9. The composition of claim 1 , wherein the polymer processing additive is a fluoropolymer having a Mooney viscosity ML 1+10 @ 121° C. in a range from 30 to 90.
10. The composition of claim 1 , wherein the combined weight of the polymer processing additive and the polymer processing additive synergist is in a range from 0.01 percent to 10 percent, based on the total weight of the composition.
11. The composition of claim 1 , wherein the polymer processing additive is a fluoropolymer.
12. The composition of claim 1 , wherein the polymer processing additive is a silicone-containing polymer.
13. The composition of claim 1 , wherein the metal salt is a sodium or potassium salt.
14. A method of reducing melt defects during the extrusion of the polyolefin, the method comprising extruding the composition of claim 1 .
15. A composition comprising:
a polyolefin;
a polymer processing additive selected from the group consisting of a fluoropolymer and a silicone-containing polymer; and
a polymer processing additive synergist comprising a polyethylene glycol and a metal salt selected from the group consisting of a metal salt of a carboxylic acid and a metal salt of a sulfonic acid, wherein the metal salt is a sodium or potassium salt, and wherein the polyethylene glycol is present at least at 85% by weight, based on the total weight of the polymer processing additive synergist.
16. The composition of claim 15 , wherein the polyolefin is a linear low density polyethylene.
17. The composition of claim 15 , wherein the polymer processing additive is a fluoropolymer having a Mooney viscosity ML 1+10 @ 121° C. in a range from 30 to 90.
18. The composition of claim 15 , wherein the metal salt is present in an amount of at least 5% by weight, based on the total weight of the polymer processing additive synergist.
19. The composition of claim 1 , wherein the polyolefin is made with a metallocene catalyst.
20. The composition of claim 1 , wherein the polyolefin is made with a single-site catalyst.