Use of polyethylene materials in the production of sterilisable liquid containers

Abstract

The present invention relates to the use of a polyethylene material in liquid containers that are sterilisable at a temperature of 100 C. during a period of >15 minutes, wherein the polyethylene material has a density >928 kg/m.sup.3 as determined according to ISO 1183-1, method A, and a melt mass flow rate of 0.50 and 51.00 g/10 min as determined according to ISO 1133-1 at a temperature of 190 C. and a load of 2.16 kg; wherein the polyethylene material produced in a high-pressure free-radical polymerisation process at a pressure of 1600 bar.

Claims

1. A liquid container, comprising: a polyethylene material having a density 928 and 930 kg/m.sup.3 as determined according to ISO 1183-1 (2012), method A, and a melt mass flow rate of 0.50 and 0.7 g/10 min as determined according to ISO 1133-1 (2011) at a temperature of 190 C. and a load of 2.16 kg; wherein the polyethylene material was produced in a high-pressure free-radical polymerisation process at a pressure of 1600 bar; the liquid container has a wall thickness of 1600 bar; the liquid container is sterilisable at a temperature of 100 C. during a period of 15 minutes.

2. The liquid container of claim 1, wherein the liquid container is a bottle or an intravenous bag.

3. The liquid container of claim 2, wherein the liquid container is a sealed container containing a liquid material.

4. The liquid container of claim 1, wherein the liquid container is sterilisable at a temperature of 105 C. or of 110 C.

5. The liquid container of claim 1, wherein the liquid containers is sterilisable during a period of 60 minutes.

6. The liquid container of claim 1, wherein the liquid container is produced with a BFS-process.

7. The liquid container of claim 1, wherein the liquid container consists of a single layer.

8. The liquid container of claim 1, wherein the liquid container is disposable.

9. The liquid container of claim 1, wherein the liquid container is produced via a process comprising the steps of: a) providing a melt comprising the polyethylene material; b) shaping the molten material into a tubular parison having a shape comprising an opening; c) positioning said parison in a mould having the desired shape of said liquid container, in which the parison is held at such temperature that the parison may be shaped into the shape of the liquid container by pressurising the inside of the parison with a pressurised gas to form the liquid container having at least one opening; d) filling the liquid container with a product for intravenous treatment; and e) sealing the at least one opening of the liquid container.

10. The liquid container according to claim 9 wherein the liquid container was produced via a process in which the sealing step e) is performed by heating the material of the liquid container in the area of the opening to a temperature above the softening temperature to provide an area of softened material; sealing of the opening by bringing the softened material of the liquid container into such contact that the opening is closed; and cooling of the softened material to a temperature below the softening temperature.

11. The liquid container of claim 1, wherein the polyethylene material is made in a tubular reactor.

12. The liquid container of claim 1, wherein the liquid container has a wall thickness of 20 m and 150 m.

13. The liquid container of claim 1, wherein the polyethylene material is produced in a high-pressure free-radical polymerisation process at a pressure of 2400 bar.

14. The liquid container of claim 1, wherein the liquid container is sterilisable at a temperature of 105 C. during a period of 60 minutes.

15. A liquid container, comprising: a polyethylene material having a density 928 and 930 kg/m.sup.3 as determined according to ISO 1183-1 (2012), method A, and a melt mass flow rate of 0.50 and 0.6 g/10 min as determined according to ISO 1133-1 (2011) at a temperature of 190 C. and a load of 2.16 kg; wherein the polyethylene material was produced in a high-pressure free-radical polymerisation process at a pressure of 2400 bar; the liquid container has a wall thickness of 20 m and 150 m; and the liquid container is sterilisable at a temperature of 105 C. during a period of 60 minutes.

Description

(1) The invention will now be illustrated by the following non-limiting examples.

(2) Liquid containers were prepared in the same way for example I and II on a Rommelag Bottlepack 321 Blow-Fill-Seal machine. The only difference thus being in the material used.

(3) Example I was performed according to the invention; example II was performed using a polyethylene material for comparative purposes.

(4) TABLE-US-00001 Example I II (comparative) Polyethylene material PE-A PE-B Density 928 kg/m.sup.3 927 kg/m.sup.3 Melt mass flow rate 0.55 g/10 min 0.30 g/10 min Shape stability during Good Poor; bumps/rippling sterilisation occurring

(5) PE-A was a polyethylene of the grade SABIC LDPE PCG06 obtainable from SABIC, produced in a tubular high-pressure free-radical polymerisation process at a pressure of 2800 bar; PE-B was a polyethylene of the grade PE3020D obtainable from LyondellBasell.

(6) The density was determined in accordance with ISO 1183-1 (2012), relating to methods for the determination of density of non-cellular plastics, using method A.

(7) The melt mass flow rate was determined in accordance with ISO 1133-1 (2011), relating to the determination of the melt mass-flow rate and the melt volume-flow rate of thermoplastics, at a temperature of 190 C. and a load of 2.16 kg.

(8) Shape stability on sterilisation is determined by subjecting liquid containers obtained from examples I and II to a sterilisation treatment with steam in an autoclave at a temperature of 106 C. for 85 minutes. After that sterilisation treatment shape stability during sterilisation has been assessed visually.

(9) The presented examples show that the use of a polyethylene material having a density of 928 kg/m.sup.3 as determined according to ISO 1183-1 (2012), method A, and a melt mass flow rate of 0.30 and 1.00 g/10 min as determined according to ISO 1133-1 (2011) at a temperature of 190 C. and a load of 2.16 kg, produced in a high-pressure free-radical polymerisation process at a pressure of 1600 bar for the production of liquid containers sterilisable at 100 C. can surprisingly lead to an significantly increased shape stability during sterilisation compared to the use of an industry standard material, frequently used for such application and having otherwise very similar properties.