SU742437A1 - Method of polyethylene production - Google Patents

Description

I

This invention relates to a process for the production of popiolefins, in particular to the synthesis of polyethylene.

A known method of producing polyethylene in a hydrocarbon solvent medium in the presence of a catalytic system consisting of titanium tetrachloride and diethyl aluminum chloride with a molar ratio of the latter and a titanium compound of 0.5: 1–12: 1 and a concentration of titanium tetrachloride of 10 mmol / l l.

The disadvantage of this method is the non-high yield of polyethylene (PE), comprising 100-125 g of PE / gTG-at-h.

The goal of the invention is to increase the yield of the polymer.

This goal is achieved by carrying out polymerization of polyethylene in a hydrocarbon solvent medium in the presence of a catalytic system consisting of titanium tetrachloride (JiCd} and diethyl aluminum chloride (AE.CCjHj.) At a molar ratio of the latter and TtCC-1, 11: 1 - 31: 1 and concentration titanium tetrachloride 0.37-0.5 6 mmol / l. For example, n-heptane is used as a hydrocarbon solvent.

Preferably, the polymerization is carried out at 7 ° C and a pressure of 4 at. .

Example 1. 10, 7 mg (0.056 mmal) TlSe. and 74.0 mg Db (CaND) (dicyclic aluminum chloride was added as a 25% -4Joro solution in n-heptane) were sealed separately into glass ampoules. The molar ratio of AtjTi 11,0. The vials were placed in a 2OO ml stainless steel reactor,

IS discharged the reactor from air and traces of moisture, injected 1OO ml of purified heptane into it and raised the temperature to,. Then ethylene was fed into the reactor up to a pressure of 4 atm and the stirrer was switched on.

Claims (3)

20 After the termination of the dissolution of ethylene in n-heptane with the help of a special device, the ampoules with the components of the catalytic system were broken and the temperature and pressure of ethylene were automatically maintained constant in the reaction zone during the entire digestion process. Two hours after the start of the polymerization, the reactor was freed from ethylene, the polymer was removed, washed with water and ethyl alcohol from the catalyst residues. The weight of the washed and dried polyethylene was 13.3 g or 124O g PE / rTiCE or 615 g PE / g Tt at-h; C 116.1 dl / g (in decalin at 135 ° C). Example 2. Under the conditions of example 1, 8.5 mg (0.045 mmol) T1 of 108.5 mg AE (.C, (At / Ti molar ratio is 2O, O) were charged to the reactor. The PE yield for 2 h was 15.3 or 18OO g PE / gT1Se4 or 89O g PE / rTi 16 dl / g (in decalin gfi). Example 3. Under the conditions of Example 1, 8.4 mg (0.044 MMonb) TiCe and 127 mg {AE / Ti molar ratio was 24.0) were charged to the reactor. The output of PE in 2 hours is 16.2 g of shge 1930 g of PE / g of TiCE4 or 955 g of PE / g of TI. watts; P1 15.7 DL / g (in decan at 135 ° C) .i Example 4. Under the conditions of example 1, 7, O mg (0.037 mmol) of T1 Se4 and 137.4 mg of UC, j) XE were charged to the reactor. ( the molar ratio At | Ti is equal to; 30.9). PE output in 2 hours 1 O, 0 g or 1428 g PE / g TiCE or 706 g PE / g Ti at.h; 16.6 dl / g (in decalin at). Claims The method of producing polyethylene by polymerizing ethylene in a hydrocarbon solvent medium in the presence of a catalytic system consisting of titanium tetrachloride and diethyl aluminum chloride, characterized in that the polymerisation is carried out at a titanium tetrachloride concentration of 0.37-0 to increase the polymer yield. , 56 mmol / l and the molar ratio of diethyl aluminum chloride and tetrachloride of titanium 11: 1 -. Sources of information taken into account in the examination 1. Patent of Germany No. 1178603, cl. 39 from 25/01, publ. 1965 (prototype).