SU1671338A1 - Method of producing tetrahydrofurane polymerization catalyst - Google Patents

Abstract

The invention relates to catalytic chemistry, in particular, a method for preparing a catalyst for the polymerization of tetrahydrofuran. The goal is to increase the activity and mechanical strength of the catalyst. It is prepared by heating montmorillonite clay, impregnating it with an organic liquid — tetrahydrofuran, activation with a strong mineral acid, washing acid off the anions, drying the activated clay, introducing into it (dry blending) 0.5 to 30% by weight of artificial graphite followed by molding, prov casting in air for 10-12 hours, drying at 100-120 ° C for 4-6 hours and calcining at 200-300 ° C for 2-4 hours. The resulting catalyst leads to an increase in polymer yield from 49 to 69.5 - 72%. The mechanical crush strength of the catalyst (at the "end") rises from 0.02 to 6.4 - 7.2 MPa. 1 tab.

Description

The invention relates to the production of catalysts for the synthesis of high molecular weight polymer compounds for the further preparation of polyurethanes.

The purpose of the invention is to increase the activity and mechanical strength of the catalyst due to the additional introduction into the activated clay by dry mixing a certain amount of carbonaceous material - artificial graphite followed by molding, air drying, drying and calcining under certain conditions.

Example 1. 110 g of montmorillonite clay dried at 100 ° C for 4 hours, impregnated with tetrahydrofuran at 25 ° C for 2 hours, activated with a 20% solution of HCI at

20 ° C for 3 hours, washed with water for 6 hours, dried at 100 ° C for 4 hours. Additional 0.5% by weight of carbon-containing material — artificial graphite (type PGM) is mixed in, then the mass is formed into cylindrical granules with a diameter of 4 ± 0.5 mm and a length of 10-15 mm, they are exposed to air for 10 hours, dried at 100 ° С, calcined at 200 ° С for 2 hours,

The catalyst is tested during the polymerization process of tetrahydrofuran under the following conditions, g:

Tetrahydrofuran1100 (15 mol)

Acetic anhydride 110 (1.05 mol)

Catalyst20.

at a temperature of 20-40 ° C for 6-8 hours with stirring.

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The strength of the catalyst is measured on an IPG-1 extensometer.

The remaining samples 2–5 were prepared similarly to sample 1. Conditions for the preparation of samples of the catalyst and the results of their tests are given in the table.

As can be seen from the data presented in the table, the use of the catalyst provides, under the specified conditions, the preparation of a polymer — polyfurite diacetate with a molecular weight of 1050-2100 and a yield of 69.5-72% in 6-8 hours, and also leads to an increase in the mechanical strength of the granules. crushing catalyst on the end to 6.4-7.2 MPa, compared with 49% and 0.02 MPa, respectively, in the case of using a catalyst prepared in a known manner.

Claims (1)

Claims A method of preparing a catalyst for polymerizing tetrahydrofuran, comprising heating montmorillonite clay, impregnating it with an organic liquid, tetrahydrofuran, activating with a strong mineral acid, washing off acid anions, drying the activated clay, characterized in that, in order to obtain a catalyst with increased activity and mechanical strength, after drying, the activated clay is additionally introduced by dry mixing 0.5-30 wt.% carbon-containing material - artificial graphite with subsequent shaping by drying in air for 10–12 h, drying at 100–120 ° C for 4–6 h and calcining at 200–300 ° C for 2–4 h,