DE432252C - Process for the production of resinous condensation products from phenols and formaldehyde - Google Patents

Description

Process for the production of resinous condensation products Phenols and formaldehyde. The known methods of making resinous Condensation products from phenols and formaldehyde are based on heating a Mixture of these two substances in the presence of a catalyst. As catalysts For example, acids or basic substances or salts are used. In contrast for this purpose, according to the invention, ßilr superoxide is used, for example barium superoxide or sodium peroxide. But it can also contain manganese superoxide or a similar superoxide Fabric to be used. The main effect is that one is much more easily colorless Products than is otherwise possible. Besides, the products are too odorless. It is also possible to start and obtain less pure starting materials still usable products. The way it works is otherwise exactly the same as in the known processes, and products of different types can be used in exactly the same way Solubility can be obtained depending on the type and duration of heating. Example x.

= 50 g raw cresol, 100 g formaldehyde solution (4%) and 5 g barium peroxide are heated to boiling under reflux until the formation of a lower Resin layer and an upper aqueous layer. One still heats-for example 1/4 to 1 / a hour to the boil, in order to lead the reaction to the end. Then the lower resin layer initially washed out with hot and then with cold water if necessary, wash out raw cresol and formaldehyde that have not yet reacted. Excess barium super-oxide can be easily removed by adding to the wash water a little dilute hydrochloric acid is added. Washing out the barium superoxide is not absolutely necessary if the phenol-formaldehyde condensation product formed Varnish (alcoholic solution) should be further processed, as it will then be after a short time Time from the alcoholic solution settles as sludge at the bottom of the vessel, from which can be easily poured off. The resulting product is in contrast to the one with Barium hydroxide obtained almost colorless and odorless. The one made from this product Lacquer (alcoholic solution) is distinguished from that from the phenol-formaldehyde condensation product obtained using barium hydroxide due to particularly good adhesiveness the end. Counterexample = a.

= 50 g raw cresol, 100 g formaldehyde solution (4%) and 5 g barium hydroxide are heated to boiling under reflux until a lower resin layer forms and form a top aqueous layer. The lower resin layer will Initially with hot water, later with cold water, possibly with additive of dilute hydrochloric acid if the product is used as an insulation material should, washed out. A brown colored, strong smell of cresol is obtained Product that provides a varnish (alcoholic solution) with low adhesive strength.

Example 2.

1509 raw cresol, 100 g formaldehyde solution (4%) and 5 g sodium peroxide are heated in the manner indicated in example i until stratification occurs, and the resin layer obtained is washed out initially with hot water and finally with cold water. There is no need to add hydrochloric acid to the washing water, as it is made up of sodium peroxide Sodium hydroxide solution which forms in the course of the reaction can be easily removed with water. That The end product is characterized by its almost complete colorlessness and odorlessness and provides a varnish (alcoholic solution) with very good adhesive strength.

Counterexample 2a.

1509 raw cresol, zoo g formaldehyde solution (4%) and 5 g sodium hydroxide are heated to boiling under reflux until a lower resin layer forms and form a top aqueous layer. The washing out happens as in the example ia specified. But this can be due to the addition of hydrochloric acid because of its easy solubility of the sodium hydroxide in water can be dispensed with. The product obtained is brown colored, smells strongly of cresol and provides a poorly adhesive varnish (alcoholic Solution). _ _ @ .-- ---- -Example 3.

150 g of raw cresol, 100 g of formaldehyde solution (4%) and 5 g of manganese peroxide (obtained by oxidation of manganese hydroxide with oxygen, so-called artificial manganese dioxide) are condensed according to the method given in Example i. The separating resin mass is initially washed warm and then cold to neutrality with the addition of a little dilute hydrochloric acid to the washing water. An almost colorless and odorless product is obtained which gives a varnish (alcoholic solution) with very good adhesive properties.

A method has already become known from patent specification 217560, alkali-soluble resinous condensation products from phenols and formaldehyde thereby to be converted into odorless, light- and air-resistant resins so that they can be used subsequently acidic or alkaline with oxidizing agents such as persulfates or perborates. In contrast, the new way of working represents a significant technical advance achieved by the condensation and oxidation of the resinous products formed takes place in one operation and also almost colorless products are obtained, while in the known processes the end products are yellow to yellow-brown in color to have.

Claims (1)

PATENT CLAIM: Process for the production of resinous condensation products from phenols and formaldehyde by heating these substances in the presence of a catalyst, characterized in that the catalysts used are alkali, alkaline earth or heavy metals --_ sxyde = use --___