CS207118B1 - Method of preparation of the epoxide resins - Google Patents

Description

Czechoslovak Socialist

REPUBLIC <1S)

DESCRIPTION OF THE INVENTION 207118 (11) (Bl)

TO THE CERTIFICATE OF CERTIFICATE '(51) Int. Cl.3 --- C 08 G 59/04 (22) Registered 14 12 79 (21) (PV 8799-79) (40) Published 15 09 80

OFFICIAL OFFICE AND DISCOVERIES (45) Published 15 08 83 (75)

The author of the invention WIESNER IVO ing., OSTÍ NAD LABEM (54) Method of preparation of epoxy resins

BACKGROUND OF THE INVENTION The present invention relates to a process for the preparation of epoxy resins by polydition diane with diepoxides.

One of the frequently used technologies for the production of epoxy resins is polyadioated oxides with diane, catalysed by the most common compounds, alkali salts, quaternary ammonium or phosphonium compounds, sulfonium compounds, betaines and the like. the second reactant is dian, which is used exclusively in solid form. The transport of reactor dianuk, handling of bags and harassment of service by toxic dian dust, presently represent very serious problems. Dian must be removed from the production line from the pelletizer and filled into pellets (scales, balls, etc.) on a packaging machine. Sacks need to be reloaded several times even when using the maximum of transport technology. For the large-scale production of epoxy resins, the solid form of dian is not the most appropriate solution, and pneumatic transport of finely ground dianos is cost-intensive. Efforts to facilitate manipulation of the Diana, saving labor and energy and, last but not least, the effort to improve the health of the working environment have led to the use of dianas in the form of easy transport and dosing into the reactor. dian or dian solutions in inert solvents. Thermal thermolabilitadian at temperatures above 130 ° C, especially above its melting point, virtually eliminates the possibility of transporting dian melt. The use of a diluent solution in solvents encounters several problems. In particular, it is low or unsatisfactory solubility of the dian in the used aromatics or aromatic mixtures with the alcoholic ketones. However, the use of more effective solvents (ketones, monoalkyl ether glycols and the like), providing sufficiently concentrated solutions, faces serious problems due to side reactions of these solvents with the reactants during the polyaddition. These types of solvents are difficult to obtain, expensive and difficult to remove from the reaction mixture. Another way to solve this technical problem is not yet known.

It has now been found that epoxy resins can be successfully prepared according to the present invention by the diepoxide polyaddition with liquid dian polyhydrate, which is obtained by separating the lower liquid phase from the emulsion existing in one of the phase regions of the dian-water system. However, the anti-technical objectives are to use only the area defined by the temperature of 99 to 140 ° C and the concentration of dian 72 to 81.8% by weight. The theoretical 207118 2 can maintain the emulsion even at temperatures above 140 ° C, but due to the considerable thermolability of the dian and the increasing heat losses it is not expedient.

The process according to the invention consists in mixing the preheated diepoxide melt with the diane liquid polyhydrate of 99-140 ° C and the known dian content while stirring, with 0.05 to 5 wt. and, if necessary, the amount of solvent required to form the azeotropic mixture, and then increase the temperature to 120-220 ° C and allow the polyaddition to proceed while distilling off the free water. The reaction is catalyzed by known catalysts, in particular alkali metal compounds such as carbonates, hydroxides, phosphates, acetates, lithium, chloride or potassium chlorides, tertiary amines, betaines, quaternary ammonium or sulfonium compounds and the like. In some cases, it is expedient to use inert solvents, most often toluene, xylene or ethylbenzene. In such cases, the liberated water is removed from the reaction mixture by binary or binary azeotropic distillation. The polyaddition is carried out for 1 to 16 hours at a temperature of 120 to 220 ° C. The polyaddition can also be carried out at temperatures above 220 ° C, but due to the large amount of polymeric gel particles and the deterioration of the product, higher temperatures are not expedient. At temperatures below 120 ° C, the polyaddition velocity is relatively slow.

The content of dian in the liquid polyhydrate is determined by measuring the dielectric constant and using calibration graphs, determining the Fischer water base or azeotropic distillation with xylene. An advantage of the method of the invention is the removal of most of the difficulties arising from the preparation, transport and use of solid form dian. The need for heavy physical work will be greatly reduced, handling will be simplified, semi-material (reduced spray loss) and packaging will be reduced. Improvement in working environment is not negligible, eliminating the possibility of toxic dian dust leakage.

The accompanying drawing shows a phase diagram of the dian-water system, where A is the existence of two liquid immiscible phases, of which the lighter phase is the aqueous solution of dian, the heavier phase is the liquid polyhydrate of the diaphragm, B is the region of homogeneous solution to dian hydrate in water, C is the region of existence of a crystalline mixture of dian hydrate with water, D is the region of existence of a suspension of crystalline dian polyhydrate in water and Pe is a ee point. The regions are limited in the diagram by the curves a, b, c, d. The eutectic point is influenced by the impurities contained in the dian, With the increasing content of impurities, the point can drop by as much as 10 ° C, thereby also affecting the position of the badv diagrams. it is not significant for the subject matter of the invention.

The two-phase mixture from area A cannot be used as a substitute for the dian, because a mixture of uncontrollable water and / or an uncontrolled amount of water would be dispensed with. weak roztokudianu in the water. Therefore, the tempered two-phase mixture (emulsion) must be subjected to a lower phase separation f2, formed by a liquid polythene wire dian, then used for polyaddition. Example 1

680 g (2 moles) of bis- (glycidyl) ether dianne are introduced into a sulfur-containing three-necked flask equipped with a stirrer, a contact thermometer and an azeotropic distillation attachment and 317 g are added with stirring at 80-85 ° C. % dian polyhydroxy pentahydrate (140 ° C) and 72.0% wt. dianu. The mixture was diluted with toluene (200 g), lithium carbonate (0.09 g) was added, and the temperature was raised to 120 DEG C. and the water released by simultaneous azeotropic distillation. The polymer is typically completed after 6.5 hours. The progress of the polyaddition is monitored by measuring the changes in water conductivity or by monitoring the decrease in the dian content. The product was removed by vacuum distillation. The product is an epoxy resin containing 0.211 epoxy / 100 g with a softening point of 66 ° C. Example 2

Into the sulfurization flask described in Example 1, 454.5 g of an epoxy resin containing 0.211 epoxy / 100 g having an Ec of 0.220 epoxy / 100 g average molecular weight of 909 are introduced. Under a nitrogen atmosphere, the resin is melted and heated to 90-95 ° C, 264.2 g of liquid dianium dihydrate (f2) at 100 ° C and 86.4 wt. % dianu. 70 gxylene and 1.8 g benzyldibutylamine are added to the mixture and then heated to 180 ° C with simultaneous azeo-distillation of the water released. In order to achieve the desired temperature, the amount of xylene in the mixture during the polyaddition is adjusted as needed. After the dian had reacted (about 3 hours), the reaction product was cooled to 80-100 ° C and diluted to 50% with a solvent mixture consisting of equal parts xylene and isobutanol. 100% resin contained 0.031 epoxy / 100g and its softening point was 167. ° C (ring-ball). Example 3

The apparatus described in Example 1 is charged with 1165 g (3 moles) of a low molecular weight epoxy resin containing 0.515 epoxy / 100 g and 0.51% chlorine. The resin is heated to 120 ° C, whereupon 285.2 gcdian polyhydrate of 110 ° C and 85.0 wt. % dianu. 2.1 g of lauryltrimethylammonium bromide are added to the stirred mixture and the mixture is heated with simultaneous distillation of the free water to 150 ° C where it is kept for 3 hours, whereupon the residual moisture is evaporated under vacuum. The product is an epoxy resin containing 0.256 epoxy / 100 g at a softening point of 50.5 ° C.

Claims (1)

3 A process for the preparation of diepoxide diane epoxy resin with an average molecular weight of 340 to 1100 at a temperature of 120 to 220 ° C and a dian to di-epoxide molar ratio of 1: 1.2 to 3, catalysed by basic compounds, alkali metal compounds, betai-object. FILLED, ammonium or phosphonium compounds, optionally in the presence of solvents, characterized in that the diepoxide is mixed with the dian liquid polyhydrate at 99 to 140 ° C and the polyaddition is carried out. drawing