Aluminum container containing dicarbonate

Abstract

The invention relates to aluminium vessels containing dicarbonic diesters and to a method for producing the packaged dicarbonic diesters.

Claims

1. An aluminium vessel having a product contained therein, comprising: an inside containing the product therein, wherein the product comprises at least one compound selected from the group of dimethyl dicarbonate and diethyl dicarbonate, and wherein said inside is coated with a polymer layer that comprises at least one polymer which is a polyester prepared from at least a pyromellitic dianhydride, a tricyclodecanedimethanol and a crosslinker comprising isophorone diisocyanate.

2. The aluminium vessel according to claim 1, wherein the at least one compound fills the vessel in an amount of 90 to 100%, based on a total amount by volume of products filling the vessel.

3. The aluminium vessel according to claim 1, further comprising fillers and/or pigments, wherein the amount of fillers and/or pigments is less than or equal to 50 ppm of the polymer layer.

4. The aluminium vessel according to claim 1, wherein the polymer layer has a thickness of 5 to 10 ?m.

5. The aluminium vessel according to claim 1, wherein the at least one polymer has an average molecular weight (MVV) of 1000 to 7500 g/mol.

6. The aluminium vessel according to claim 1, wherein the at least one polymer is a polyester having a glass transition temperature of less than or equal to 100? C.

Description

EXAMPLES

Example 1

(1) Production of the Coated Aluminium Vessel

(2) A polyester resin varnish (Goldlack BT651B (from Valspar Corp.)) was applied by spraying to the aluminium surface, more particularly to the surface facing the filled product. The vessel was then heated at 190? C. for 10 min. Thereafter the uniformity of the coating was examined optically.

Example 2

(3) Filling of the Aluminium Vessel With Dimethyl Dicarbonate

(4) The coated aluminium bottles from Example 1 are filled with dimethyl dicarbonate and sealed directly with a plastic cap from Bericap, Budenheim. The caps have a polytetrafluoroethylene (PTFE) seal. The seal is available commercially under the name Plytrax 100 and was obtained from Norton Performance Plastic Corporation, Wayne, NJ, USA.

Example 3

(5) Stability Tests of Dimethyl Dicarbonate In Different Containers

(6) 3 kg of dimethyl dicarbonate were filled into different containers, available commercially and produced experimentally, as listed in Table 1, and the containers were then sealed and placed for storage into various temperature cabinets. The conditions, in other words the storage time and the storage temperature, under which the filled product was stored in the containers can be seen from Table 1. Analysis was carried out by gas chromatography; in this case, a determination was made of the amount of dimethyl carbonate present, which is a breakdown product in the thermal decomposition of dimethyl dicarbonate. Where a high quantity of dimethyl carbonate is found, this is representative of a low stability of the dimethyl dicarbonate.

(7) TABLE-US-00001 TABLE 1 Storage temperature Dimethyl carbonate content [? C.] [ppm]/after X days' storage Aluminium, uncoated 20 6724 ppm/35 days (from Leicht und Appelt, Bad Gandersheim, GER) Aluminium anodized (from 20 4462 ppm/35 days Leicht und Appelt, Bad Gandersheim, GER) Glass 20/40/20* 19 591 ppm/168 days Polyester resin varnish, 20/40/20* 120 ppm/365 days coated on aluminium, with a pigment content of less than 300 ppm. (Goldlack BT651B (from Valspar Corp. AG, Gr?ningen, CH) Polyester resin varnish 20/40/20* 840 ppm/365 days coated on aluminium, with a pigment content of less than 300 ppm. (Goldlack 32S23MC (from Valspar Corp. AG, Gr?ningen, CH) *5 weeks' storage at 20? C., then 4 weeks at 40? C., then continued storage at 20? C.

(8) As can be seen from Table 1, dimethyl dicarbonate can be stored for much longer, and hence more stably, in aluminium vessels coated with polyester varnish than in uncoated or anodized aluminium vessels.