DE1044406B - Process for the production of polyesters of carbonic acid - Google Patents

Description

It is already known to produce carbonic acid with a low softening point by reacting polyesters Manufacture dialkyl carbonates with glycols. Oily to soft waxy products are obtained by using bischlorocarbonic acid esters of glycols with polyhydric phenols or dichlorocarbonic acid esters polyvalent Reacts phenols with glycols with the addition of tertiary bases in stoichiometric amounts. High molecular weight fiber- and fihn-forming products cannot be obtained in this way because the tertiary Bases easily split off carbon dioxide from the chlorocarbonic acid esters. Also made from phosgene and polyvalent ones Phenols, polyesters of carbonic acid can be obtained. In this case, solid plastic-like ones are obtained Products that are however insoluble and at higher levels Easily decompose at temperatures.

Recently, various processes have been described in which high molecular weight fiber and film-forming Polyesters of carbonic acid are obtained, the diarylalkane groups linked via ester bridges contain. So you can bis (hydroxyaryl) alkanes with phosgene or with bis-chlorocarbonic acid esters of Implement bis (hydroxyaryl) alkanes in absolute pyridine or in aqueous alkalis. The bis (hydroxyaryl) alkanes can also be converted into polyester with diphenyl esters of carbonic acid. To Mixtures of bis (hydroxyaryl) alkanes and glycols in polyester can now also use this method Carbonic acid are transferred. However, the products obtained are less high molecular weight and have a irregular structure, because the glycols used react by breaking the chain and are not completely amalgamated Participate in sales.

It has been found that carbonic acid polyesters of regular structure with alternating aromatic and aliphatic groups obtained when bis-chlorocarbonic acid esters of glycols in aqueous alkaline Reacts medium with dihydroxyaryl compounds. Suitable bis-chlorocarbonic acid esters are, for. B. those of the glycols 1,2-ethylene glycol, 1,4-butanediol, 1,6-hexanediol, 2,5-hexanediol, bis (hydroxy) ethyl-4-oxaryl) dimethyl methane or 1,4-hexenediol. As dihydroxyaryl compounds, for. B. hydroquinone, Use resorcinol or catechol. The use of bis (hydroxyaryl) alkanes is usually particularly advantageous. This class of compounds includes e.g. B. (4,4'-Dihydroxydiphenyl) methane, 1,1- (4,4'-Dihydroxydiphenyl) -cyclohexane, 3,4- (4,4'-dihydroxydiphenyl) -hexane, 2,2- (4,4'-dihydroxydiphenyl) -propane, l, l- (4,4'-dihydroxydiphenyl) -l-phenylethane, 2,2- (2,2'-dihydroxy-4,4'-di-tert-butyldiphenyl) propane, 1,1- (4,4'-Dihydroxy-3,3'-dimethyldiphenyl) cyclohexane. Mixtures of these dihydroxyaryl compounds can also be used Advantage can be used.

Method of manufacture
of carbonic acid polyesters

Applicant:

Aniline & Soda Factory in Baden

Corporation,

Ludwigshafen / Rhine

Dr. Horst Gölz, Schwetzingen,

and Dr. Ferdinand Meyer, Ziegelhausen,

have been named as inventors

The bis-chlorocarbonic acid ester of a glycol is expediently added to an aqueous alkaline solution or Suspension of a dihydroxyaryl compound. It is often beneficial to use an inert organic solvent admit. Particularly aliphatic and aromatic hydrocarbons are used as organic solvents into consideration, which may contain halogen, for example xylene, chloroform or methylene chloride. You let them both components act on each other until a tough polycondensation product is formed indicates the end of the reaction. The reaction can be started by adding tertiary amines or their quaternary Speed up salting. In general, the components are left on top of one another in approximately equivalent amounts

act, but the use of an excess of dichlorocarbonic acid ester of up to about 10% is often advantageous. The reaction is usually carried out at room temperature.

The products obtained are thermoplastic and can be valuable directly or from their solutions Foils, films or threads are processed.

example 1

57 parts of bis (4-hydroxyphenyl) dimethyl methane are added to a solution of 30 parts of sodium hydroxide in 300 parts of water and added 50 parts of methylene chloride. To the suspension obtained is added in the course of about 4 hours with cooling at about 20 ° C. 59 parts of 1,4-butanediol-bis-chlorocarbonic acid ester. Then stir a few hours, expediently after adding 2 parts of dimethylbenzylammonium chloride, and then separates the aqueous layer from the organic layer. After evaporation of the solvent, a tough, almost colorless product that dissolves in methylene chloride

809.679 / 438

is soluble and processed into films from this solution can be. The k value of this product, in m-cresol determined, is 65, its softening point, 190 ° C.

Example 2

200 parts are added to a solution of 110 parts of p-hydroquinone in 1200 parts of 10% sodium hydroxide solution Xylene and then with cooling at room temperature within 3 hours 260 parts of 1,6-hexanediol dichlorocarbonic acid ester. After stirring for a few hours at room temperature, the polycondensate becomes worked up as described in Example 1. A pale pink colored product is obtained, the k value of which in mJKresol- determined, is 59. It can be seen from the Spin the melt into threads.

Claims (2)

Patent claims: 5. 1. Process for the production of polyesters of the Carbonic acid from bis-chlorocarbonic acid esters of glycols and dihydroxyaryl compounds, characterized in that the reaction takes place in aqueous alkaline Medium, optionally with the addition of an ίο indifferent solvent, is made. 2. The method according to claim 1, characterized in that that quaternary ammonium salts are added as a reaction accelerator.