Compositions for injection moulding
Use of a filled polymer resin in the manufacture of an article therefrom by injection moulding, a method of manufacturing an article by injection moulding a filled polymer resin, a method for enabling or improving the injection mouldability of a polymer resin comprising recycled polymer, wherein the polymer resin comprises recycled polymer and functional filler, the use of a functional filler in a polymer resin comprising recycled polymer to improve the injection mouldability of the polymer resin, an article of manufacture obtained by injection moulding a filled polymer resin, and a filled polymer resin.
1. An article of manufacture obtained by injection moulding a filled polymer resin comprising a recycled polymer and a functional filler,
wherein the functional filler comprises an inorganic particulate that (i) is surface treated or (ii) has a d 50 of less than about 2.5 μm, and
wherein the filled polymer resin has:
(1) a MFI at 2.16 kg/190° C. which is lower than then MFI of the filled polymer resin during injection moulding;
(2) a MFI at 2.16 kg/190° C. which is at least 3 g/10 mins lower than the MFI of the filled polymer resin during injection moulding; or
(3) a MFI of less than about 2.6 g/10 mins at 2.16 kg/190° C.,
wherein the inorganic particulate is calcium carbonate; and
wherein the article has a wall having a thickness of no more than about 5 mm.
2. The article according to claim 1 , wherein the filled polymer resin has a MFI of less than 2.5 g/10 mins at 2.16 kg/190° C.
3. The article according to claim 1 , wherein the filled polymer resin has a MFI of less than about 2.5 g/10 mins at 2.16 kg/190° C. and also has (a) a Spiral Flow Number (SFN) which is at least 80% of the SFN of an unfilled virgin HDPE resin having a MFI of at least about 5.0 g/10 min at 2.16 kg/190° C., and/or (b) a SFN which is at least 8% of the SFN of an unfilled virgin HDPE polymer resin having a MFI of 8 g/10 mins at 2.16 kg/190° C.
4. The article according to claim 3 , wherein the filled polymer resin has a MFI equal to or less than about 1.0 g/10 mins at 2.16 kg/190° C.
5. The article according to claim 1 , wherein the filled polymer resin also has a R-FMI of at least about 100, wherein
R-MFI=(MFI at 21.6 kg)/(MFI at 2.16 kg), and
wherein (MFI at 21.6 kg)−(MFI at 2.16 kg) is at least about 40.
6. The article according to claim 1 , wherein the filled polymer resin also has a Spiral Flow Number (SFN) of at least about 350 mm.
7. The article according to claim 1 , wherein the filled polymer resin comprises at least about 50% by weight recycled polymer.
8. The article according to claim 1 , wherein the recycled polymer comprises
a mixture of polyethylene and polypropylene,
a mixture of different types of polyethylene,
a mixture of different types of polyethylene and polypropylene, or
another mixture of polymer types.
9. The article according to claim 1 , wherein the filled polymer resin is free of virgin polymer.
10. The article according to claim 1 , wherein the functional filler is an uncoated inorganic particulate having a d 50 of no greater than about 1.0 μm.
11. The article according to claim 1 , wherein the functional filler comprises or is a surface-treated inorganic particulate having a d 50 of from about 0.1 to 2.5 μm.
12. The article according to claim 1 , wherein the inorganic particulate is surface-treated with a surface treatment agent selected from a compound including a hydrocarbyl unsaturation and an O- and/or N-containing acid functionality, and/or a compound having a saturated hydrocarbyl group and an O- or N-containing acid functionality.
13. The article according to claim 1 , wherein the filled polymer resin further comprises an impact modifier.
14. The article according to claim 1 , wherein the filled polymer resin further comprises from about 0.01 wt. % to about 0.05 wt. % of di-cumyl peroxide or 1,1-Di(tert-butylperoxy)-3,3,5-trimethylcyclohexane or other a peroxide-containing additive, based on the total weight of the filled polymer resin.
15. The article according to claim 14 , wherein the filled polymer resin comprises from about 0.015 wt. % to about 0.025 wt. % of the di-cumyl peroxide or 1,1-Di(tert-butylperoxy)-3,3,5-trimethylcyclohexane or other peroxide-containing additive.
16. The article according to claim 1 , wherein the filled polymer resin further comprises up to 3 wt. % carbon black and up to about 0.5 wt. % antioxidant, based on the total weight of the filled polymer resin.
17. The article according to claim 1 , wherein the recycled polymer of the filled polymer resin, other than impact modifier when present, consists of polyethylene and polypropylene derived from a recycled mixed polyolefin feed.
18. The article according to claim 1 , wherein the article has a wall having a thickness of no more than about 3 mm.
19. The article according to claim 1 , wherein the article has one or more of:
(a) an elongation at break of at least about 300%,
(b) a UTS of at least about 20 MPa,
(c) a flexural modulus of at least about 90 MPa, and
(d) a Charpy Impact Strength of at least about 40 KJ/m 2 (20° C.±2° C.).
20. The article according to claim 1 , wherein the article has an elongation at break of at least about 300%.
21. The article according to claim 1 , wherein the article has a UTS of at least about 20 MPa.
22. The article according to claim 1 , wherein the article has a flexural modulus of at least about 900 MPa.
23. The article according to claim 1 , wherein the article has a Charpy Impact Strength of at least about 40 kJ/m 2 (20° C.±2° C.).