CONCENTRATE FOR POLYESTER-BASED MATERIALS

Abstract

The invention discloses a concentrate comprising polymethylpentene and titanium dioxide, a process for preparing polyester-based preforms and containers, a use of said concentrate, and a container product. The concentrate of the invention comprises 20-90% polymethylpentene, and 10-80% titanium dioxide, based on the weight of the concentrate.

Claims

1. A concentrate comprising 20-90% of polymethylpentene, and 10-80% of titanium dioxide, based on total weight of the concentrate.

2. The concentrate of claim 1, wherein the polymethylpentene is a homopolymer, copolymer or a mixture thereof.

3. The concentrate of claim 1, further comprising polyester.

4. The concentrate of claim 1, further comprising aliphatic polymer or aromatic polymer.

5. (canceled)

6. The concentrate of claim 3, wherein the polyester comprises one or more selected from the group consisting of aliphatic homopolymer polyesters, aliphatic copolymer polyesters, semi-aromatic copolymer polyesters, semi-aromatic homopolymer polyesters, aromatic copolymer polyesters, and aromatic homopolymer polyesters.

7. The concentrate of claim 4, wherein the aromatic polymer comprises one or more selected from the group consisting of polystyrene, polysulphone, polyphenylsulphone, and acrylonitrile-butadiene-styrene, and the aliphatic polymer comprises one or more selected from the group consisting of polyethylene, and polypropylene.

8. The concentrate of claim 1, further comprising a light absorbing additive.

9. The concentrate of claim 8, wherein the light absorbing additive is a pigment and/or dye.

10. A compound formulation comprising a polymethylpentene, titanium dioxide, and a polyester resin, wherein the compound formulation comprises 1-10% of polymethylpentene and 0.5-15% of titanium dioxide, based on total weight of the compound formulation.

11. A method of colouring polyester, comprising adding the concentrate of claim 1 to the polyester.

12. A method of colouring polyester, comprising adding the compound formulation of claim 10 to the polyester.

13. The method of claim 11, wherein the polyester is a polyester preform for bottles or other containers.

14. The method of claim 13, wherein the amount of polymethylpentene is 5% or less by total weight of the preform.

15. The method of claim 13, wherein the amount of titanium dioxide is 8% or less by total weight of the preform.

16. A process for preparing polyester-based containers suitable for storing solids and/or liquids and having a 0-2% transmission at 550 nm and 0.3 mm sample thickness, said process comprising producing a preform for said containers from the polyester and the concentrate of claim 1, and moulding the preform into a container.

17. A process for preparing polyester-based containers suitable for storing solids and/or liquids and having a 0-2% transmission at 550 nm and 0.3 mm sample thickness, said process comprising producing a preform for said containers from the polyester and the compound formulation of claim 10, and moulding the preform into a container.

18. The process of claim 16, wherein the amount of concentrate is 4-8% by total weight of the polyester-based container.

19. A container product obtainable by the process of claim 16, wherein the amount of polymethylpentene is 5% or less by total weight of the container.

20. A container product obtainable by the process of claim 16, wherein the amount of titanium dioxide is 8% or less by total weight of the container.

21. The method of claim 12, wherein the polyester is a polyester preform for bottles or other containers.

22. The method of claim 21, wherein the amount of polymethylpentene is 5% or less by total weight of the preform.

23. The method of claim 21, wherein the amount of titanium dioxide is 8% or less by total weight of the preform.

Description

EXAMPLES

Example 1

[0083] PET bottles were prepared including amounts of 1 wt. % and 3 wt. % of selected polymers. These polymers were Moplen HP500N (homopolymer of polypropylene from LyondellBasell Industries), polymethylpentene (from Mitsui), Hostalen XP112-I (random copolymer polypropylene from LyondellBasell Industries), LLDPE 1050B (linear low-density polyethylene from Dow Chemical Company), Polybutene-1 PB 0800M (homopolymer of polybutene-1 from LyondellBasell Industries), PLEXIGLAS® 8N (polymethylmethacrylate (PMMA) from Evonik Industries) and Vistamaxx 6202 FL (from Exxon Mobil). The polyester preforms (Invista T94N PET resin (IV=0.84 dl/g)), 25 g preform for 0.5 litre bottle with PCO neck finish) were made on an Arburg Allrounder 320 (extruder temperature profile, hot runner temperatures were set at 285° C.), equipped with a Piovan T200 dryer and DB-60 control unit (PET was dried to a dew point of −45° C.). Dosing of the polymer into the PET base resin was done using a Movacolor MCBalance. Some polymers could not be processed at 3 wt. % and were excluded from further work. Preforms were blown on a Corpoplast LB01 using standard PET bottle blowing settings. The transmission curves from 200 to 750 nm of the blown bottles (0.30 mm wall thickness) were collected using a Cary 5000 spectrometer equipped with an integrating sphere. The percent transmission at 550 nm was determined from the transmission curves and is shown in FIG. 1. As can be seen, the amount of light transmitted using the polymer polymethylpentene is significantly lower, at the critical wavelength of below 550 nm and below, than with the selected standards at the concentration of 1% and 3%.

Example 2

[0084] A mixture of 800 gram polymer and 1200 gram titanium dioxide was mixed and processed on a laboratory extruder (APV 19 mm twin screw) with a temperature profile between 270 and 240° C. at 300 rpm. The percent of polymer by weight included in the concentrate is 40%, the weight of titanium dioxide included in the concentrate is 60%.

[0085] Several concentrates were prepared as described above, with selected carrier polymers. The concentrates containing these polymers were used to prepare polyester preforms and bottles.

[0086] The colour concentrates were used to produce polyester (PET) preforms (Invista T94N resin (IV=0.84 dl/g)), 25 g preform for 0.5 litre bottle with PCO neck finish) on an Arburg Allrounder 320 (extruder temperature profile, hot runner temperatures were set at 285° C.), equipped with a Piovan T200 dryer and DB-60 control unit (PET was dried to a dew point of −45° C.). Dosing of the colour concentrates at 9 wt. % was done using a Movacolor MCBalance. Preforms were blown on a Corpoplast LB01 using standard PET bottle blowing settings. The transmission curves from 200 to 750 nm of the blown bottles were collected using a Cary 5000 equipped with an integrating sphere. The percent transmission at 550 nm was determined from the transmission curves and is shown in FIG. 2.

Example 3

[0087] Two additional colour concentrates were made in the following manner:

[0088] A mixture of 700 g polymer, 1300 g titanium dioxide was mixed and processed on a laboratory extruder (APV 19 mm twin screw) and temperature profile between 270 and 240° C. at 300 rpm. The chosen carrier polymers were PET and polymethylpentene. The percent of carrier polymer by weight included in the concentrate is 35%, the weight of titanium dioxide included in the concentrate is 65%

[0089] These concentrates with polymethylpentene and PET as carrier polymers were used to prepare polyester preforms and bottles as described in Example 2.

[0090] As can be seen from FIG. 3, the amount of titanium dioxide in the bottles to achieve a light transmission at 550 nm of 1.5% in these bottles was remarkably lower for the claimed invention.

Example 4

[0091] A mixture of 700 g polymer, 1299 g titanium dioxide and 1 g Carbon Black Pigment Black 7 (PB7) was mixed and processed on a laboratory extruder (APV 19 mm twin screw) and temperature profile between 270 and 240° C. at 300 rpm. The chosen carrier polymers were PET and polymethylpentene. The percent of carrier polymer by weight included in the concentrate is 35%, the weight of titanium dioxide included in the concentrate is 64.94%, the weight of PB7 was 0.06%.

[0092] These concentrates with polymethylpentene and PET as carrier polymers were used to prepare polyester preforms and bottles as described in Example 2, with the difference that bottles were prepared with a wall thickness of 0.2 mm.

[0093] As can be seen from FIG. 4, the amount of titanium dioxide in the bottles to achieve a light transmission at 550 nm of 0.2% in these bottles was remarkably lower for the claimed invention.