Polymer blends
Compatibilizer for a polymer blend, use of the compatabilizer in a polymer, a polymer blend comprising the compatabilizer, an article formed from the polymer blend, and methods for making the compatabilizer, polymer blend and article.
1. A compatibilizer for a polymer blend, the compatibilizer comprising a particulate and an organic linker on a surface of the particulate, wherein:
the organic linker is a basic form of an organic acid comprising an oxygen containing acid functionality and at least one carbon-carbon double bond;
the particulate is an alkaline earth metal carbonate or sulphate, a hydrous kandite clay, an anhydrous (calcined) kandite clay, or combinations thereof,
the particulate has a d 50 of from about 0.5 μm to equal to or less than 1.5 μm; and
the organic linker is:
CH2=CH—(CH2) a -Z (1)
wherein a is equal to or greater than 3; and
wherein Z is a carboxylate group, a phosphate group, a phosphite or a phosphinate group.
2. A compatibilizer according to claim 1 , wherein the organic linker is the conjugate base of said organic acid.
3. A compatibilizer according to claim 1 , wherein the organic acid is an unsaturated fatty acid or derived from an unsaturated fatty acid.
4. A compatibilizer according to claim 1 , wherein the organic linker comprises six or more carbon atoms.
5. A compatibilizer according to claim 1 , wherein a is from 6 to 10.
6. A compatibilizer according to claim 1 , wherein the organic linker is a carboxylate.
7. A compatibilizer according to claim 1 , wherein the organic acid is undecylenic acid.
8. A compatibilizer according to claim 1 , wherein the compatibilizer consists essentially of the particulate and the organic linker.
9. A compatibilizer according to claim 8 , wherein the organic linker is the basic form of undecylenic acid.
10. A compatibilizer according to claim 1 , wherein the particulate is calcium carbonate.
11. A polymer blend comprising a mixture of polyethylene and polypropylene and a compatibilizer, wherein
the compatibilizer comprises a particulate and an organic linker on a surface of the particulate, wherein
the organic linker is a basic form of an organic acid comprising an oxygen-containing acid functionality and at least one carbon-carbon double bond;
the particulate is an alkaline earth metal carbonate or sulphate, a hydrous kandite clay, an anhydrous (calcined) kandite clay, or combinations thereof;
the particulate has a d 50 of from about 0.5 μm to equal to or less than 1.5 μm; and
the organic linker is:
CH2=CH—(CH2) a -Z (1)
wherein a is equal to or greater than 3; and
wherein Z is a carboxylate group, a phosphate group, a phosphite or a phosphinate group.
12. A polymer blend according to claim 11 , further comprising a peroxide-containing additive.
13. A polymer blend according to claim 11 , wherein the compatibilizer is a first filler and the polymer blend further comprises a second filler.
14. An article comprising the polymer blend of claim 11 , wherein the article has
(i) a resilience which is at least about 50% greater than an article formed from a polymer blend comprising the mixture of different polymer types filled with only the particulate of the compatibilizer; and/or
(ii) a flexural modulus which is at least about 92% of the flexural modulus of an article formed from a polymer blend comprising the mixture of different polymer types filled with only the particulate of the compatibilizer.
15. A polymer blend according to claim 11 , wherein the polymer blend comprises at least about 50% by weight recycled polymer, based on the total weight of polymer in the polymer blend.
16. A polymer blend according to claim 11 , wherein the polymer blend comprises up to about 70% by weight of compatibilizer, based on the total weight of the polymer blend.
17. A compatibilizer according to claim 10 , wherein the calcium carbonate is ground calcium carbonate.