SU143552A1 - Method for saponification of polyvinyl acetate - Google Patents

Description

The use of azodinitrile as a polymerization initiator for various unsaturated compounds is known.

It is also known to homogeneous saponification of beaded polyvinyl acetate in methanol with caustic and fines, in an ethanol solution of ammonia and triethanolamine.

A method for the saponification of polyvinyl acetate is proposed. The initial polyvinyl acetate is obtained by bead polymerization of vinyl acetate with azodinitrile isobutyric acid initiator, and the resulting nolyvinyl acetate beaded is washed in a wet form, in a methanol solution, with caustic alkali or a mixture in the course set, in the course of the first set, in the course of time, in the course of time, in the course of time, in the course of time, in the course of time, in wet form, it is washed heterogeneously in the methanol solution with caustic alkali or mixture, and in the course of the common cause, in the course of time, in the course of time, in the course of time, in the course of time, in the course of time, in the course of time, it is wetted with alkali or a mixture of methanolic solution, imitated with alkali or mixture, and in the course of the common cause, in the course of time, in the course of time, in the course of time, in the course of time, in the course of time, it is washed with an alkaline mixture or a mixture of nitric acid and a mixture of nitric acid and a mixture of nitric acid; polyvinyl alcohol which can be dissolved in water. The resulting product is insoluble in the original monomer, alcohols and hydrocarbons, but swells in them.

The use of heterogeneous saponification of beaded polyvinyl acetate in methanol solution of amines is unknown.

Example 1. In two parts of an aqueous solution containing 0.02-0.05% polyvinyl alcohol with 10-15% perchidated acetate groups, one weight part of vinyl acetate is added with 0.2-0.4% azodinitrile iso-oxyde dissolved in it acid. The polymerization reaction is carried out when moving and a temperature of 65-90 for 3-5 hours. The resulting polyvinyl acetate bead is tromped with water and centrifuged to a content of 10-12% moisture. Wet polyvinyl acetate beads are washed in methanol solution of caustic soda (at the rate of 3-5 moles of caustic soda per 100 mOJ: polyvinyl acetate) at a temperature of 40-60.

Example 2. Beaded polyvinyl acetate is placed in methanol at a weight ratio of 1: 5 and saturated with dry ammonia and obtained in laboratory conditions from ammonium chloride and caustic soda in an amount of 0.2-0.5 mol of ammonia per one mol of polyvinyl acetate.

No. 143552

.,.

-.) V, X

Reaction drrhod # Gt w and room temperature with the formation of a powder-adJi-HBH wrtoepro alcohol. Depending on the dosage of am-miak. It is possible to get lolochiticholivinilovogo alcohol with different content of ostatrnyh: acetate groups. The quickest way is to wash the bead; polyvinyl acetate in methanol with ammonia in the cold for 4-5 hours and additionally cleansing acetate groups with a small amount of caustic soda.

 Example 3. Saponification of beaded polyvinyl acetate in methanol with triethanolamine (a mixture of mono-, di-, and triethanolamine) was carried out with an equimolar amount of the latter for 4-5 hours at 40-50 ° to form polyvinyl alcohol having properties similar to those previously indicated.

The polyvinyl alcohol film did not swell in organic solvents. The specific gravity of the product is 1.3 kg / cm, the tensile strength is 1300 kg / cm, which is in accordance with the indicators for polyvinyl alcohol. At the conclusion of the PIIPPlastic, testing polyvinyl alcohol samples from beaded polyvinyl acetate to obtain synthetic fiber gave positive results, but the samples are somewhat inferior in lacquer polymer in terms of strength and color.

Subject invention

The process of saponification of polyvinyl acetate by treating it in methanol with a mixture of MONO-, di-, and triethanolamine, characterized in that a beaded polyvinyl acetate is exposed to amines.