DE857946C - Process for the polymerization of propylene - Google Patents

Description

Process for the polymerization of propylene It is known that one from propylene by treatment with catalysts of the Friedel-Crafts reaction can obtain more or less high molecular weight polymers. As far as this one high Viscosity of e.g. B. io to 20 ° E or above at 99`, they are excellent as insulating oils for electrical purposes, in particular as cable insulating oils. they draw namely not only because of the high viscosity, but also because of its low viscosity Viscosity index, high flash point and excellent electrical properties the end. However, their use for this purpose has so far failed due to their difficult accessibility. You could only get them in limited quantities together with large quantities in proportion Produce low molecular weight polymers that are not for technical purposes or are difficult to use. It is true that the formation of high molecular weight polymers in the polymerization of propylene by means of Friedel-Crafts' catalysts Reaction by using low polymerization temperatures support financially, but then the rate of polymerization is so slow that such a procedure is no longer suitable for the industrial production of the polymers mentioned.

It has now been found that high-quality polymers of propylene, which are ideally suited as insulating oils for electrical purposes, without the aforementioned Disadvantages are obtained if the propylene is preferably used at temperatures below -30 "- at about its boiling point, using aluminum chloride with the addition of hydrogen halide or compounds which split off hydrogen halide. As hydrogen halide or compounds which split off hydrogen halide are particularly suitable and the alkyl chlorides, but you can also use the corresponding bromine, iodine or Fluorine compounds work, although generally they are not as effective.

The additives mentioned are usually in amounts of a few Percent (based on propylene) applied. With the additions mentioned, the Polymerization is accelerated so that within a relatively short time, e.g. B. less hours, almost all of the propylene in a high quality, for the said Purposes suitable polymer can be transferred. The rate of polymerization generally increases with the amount of the additives mentioned.

Example i 9500 parts of liquid propylene are mixed with 750 parts of aluminum chloride at -48 '. A slow stream of hydrogen chloride gas is now passed into the propylene. After one hour of reaction, a 97.5% yield of 01 is obtained with a viscosity of 1.520E at 99t ° 'and 292.1'E at 5o °, a flash point of 23o ° and a viscosity index of 25. The specific resistance of the Oil is io1e O'hm X cm, and the loss factor determined with a frequency of 50 Hz is smaller than io-3.

Example 2 300 parts of liquid propylene are mixed with 5% tert-butyl chloride at -48 ° mixed. After the addition of 15 parts of aluminum chloride, a rather violent reaction occurs A reaction that ends after 25 minutes at the boiling point of propylene. : Ulan obtained in a yield of 94% an oil with a viscosity of 7.73 ° E at 99 ° and from 152.6 ° E at 5o °. The viscosity index is 30 and the flash point is 216 °.

If the same amount of amyl bromide is used instead of tert-butyl chloride, a C51 with a viscosity of 18.22 ° E at 99 °, a viscosity index of 30 and a flash point of 220 ° is obtained after 3 hours.

Lead Example 3 A mixture of 150 parts of propylene and 7.5 parts of aluminum chloride at -80 ° with 5% tert-butyl chloride. After 12 hours an oil with a viscosity of 1.5 ° C. is obtained in a yield of 86% 99 °, a viscosity index of 32 and a flash point of 218 °.

Claims (1)

PAi'E \ TA \ SPRUCH: Process for the production of high molecular weight polymers by treating propylene with aluminum chloride at low temperatures, thereby characterized that at temperatures below -30 °, preferably at about Boiling point of propylene, and in the presence of hydrogen halide or hydrogen halide Compounds, especially hydrogen chloride or alkyl chlorides, works.