DE436779C - Process for the production of resinous condensation products, especially those from phenols and aldehydes - Google Patents

Description

Process for the production of resinous condensation products, especially those made from phenols and aldehydes. The manufacture of resinous Condensation products, especially those from phenols and aldehydes, takes place as is known, in such a way that the constituents of the reaction are first, if appropriate in the presence of condensation agents, allow them to react with one another for some time, whereupon the product formed immediately or after prior separation of water is evaporated until the desired consistency is achieved.

The technical implementation of this general procedure offers certain Trouble. Above all, it is almost impossible to check the temperature conditions to regulate within a larger resin mass. like this with regard to the Security of the result would be desirable. This is particularly annoying then noticeable when HaTZe of the so-called resol class are made from phenols and formaldehyde because these resins are easily, sometimes even within the device, undergo a transformation into insoluble and infusible products, their premature Creation must therefore be carefully avoided.

A well-known further drawback, especially of all phenol aldehyde resins is also the always very strong smell of phenol that some consumers, e.g. B. Manufacturer of paint, very annoying. Because technically a resin production with uniform and pure phenols, e.g. B. Pure phenol (C,; H; OH) itself, for obvious reasons separates out, rather primarily the technical mixture of the three isomeric cresols (Raw cresol, commercial cresol) must be used, but the three cresol isomers are known react with aldehydes at different speeds, so there is always more or less large amounts of unconnected phenols in the resin, their removal so far unsuccessful was. Of course, the difficulties increase in this direction with impure ones Starting materials, e.g. B. hydrocarbon-containing primordial tar phenols, even more and influence then also the other properties, such as solubility, melting point, etc.

One can avoid all indicated evils and beyond still achieve considerable other advantages, if -mari- on the hitherto usual evaporation larger; cups, which often weigh several thousand pounds, are dispensed with and the procedure set up so that only a relatively small amount at a time for evaporation arrived .. Because then it is. which in itself could not be foreseen without further ado, possible to choose ar = working conditions which of those for treatment the - total. dimensions may differ significantly. It is special then with ease possible to use temperatures so high that the effect is achieved within a very short time and with certainty, whereby so not just completing the chemical_Umsetzung "but the complete elimination of all volatile products is also guaranteed.

The essence of the new process is therefore the one to be evaporated Mass in a continuous manner and in relatively small lengths to one to distribute a large surface, then in a finely distributed state for a short time Time to subject it to high heating and then immediately to any further action to withdraw from the heat. By appropriately coordinating these measures, it is without Difficulty possible to bring the "'experience to implementation so quickly, that the performance is in no way inferior to the method currently used.

The distribution of the product to be evaporated to the required large surface area can be done in different ways. So can nebulizers are used, furthermore rollers or endless belts on which the 'let, similar like a painting machine. The heating can also be effected differently, the device in question being the selected Type of distribution has to adapt. There are many ways to do this are known and essentially the devices of rapid dryers, etc. correspond.

The setting of the distribution device as well as the temperature and the duration of the heating depends, of course, on the type of evaporation resin-forming mass. As far as these are made from phenolics and aldehydes, növolak-like Deliver resins, there is no particular restriction on the choice of temperature. It is particularly surprising, however, that the new process also works with the more cautious Working. wise, which is necessary with resolute masses, excellent results leads to: -The cause is probably to be seen in the fact that at about 13o to 14o ° C, which have turned out to be the appropriate heating temperature, the chemical conversion that yes, from the primary constituents only the resin supplies, proceed very quickly goes; but above all show the striking odorlessness of the product as well the very high melting point clearly indicates that evaporation occurs at the same time of the unconnected phenol components is a particularly good one. In what extraordinary "The extent to which the resin can be improved results from the fact that, for example, a resol from primordial tar phenols, which was produced by the usual method despite long heating of the Whole all-set up to finally 120 ° C in a vacuum with stirring never over one Melting point of about 45 ° C came out, also remained soft. And except for phenols also smelled of the tarry companions, prepared according to the present process, provides a resin that melts at 66 ° C, is brittle and almost completely odorless. aside from that the solubility of this product is even better than before.

The advantages of the new way of working are not exhausted. So you can now use the more expensive stills and auxiliary equipment, such as Vacuum pumps, do without it completely. Plus, it's easy to do the whole operation to make the resin production continuous, such. that you just get a mixture the components through a preheater, e.g. B. one heated to a suitable temperature Copper snake of a certain length can be regulated, whereupon it is preheated Mixture either immediately or after flowing through a watershed on the Distribution facility arrives. In this way, the whole process runs automatically and uses a small workforce without reducing performance. It is also possible. the finished resin from the evaporation device directly put to use. For example, one working with spray devices System can easily be connected to a paper coating machine. On such In addition, all the alcohol that would otherwise be used for the production of one is saved paint suitable for painting was required, which is important for such areas, in which alcohol for technical purposes can only be obtained with difficulty, considerable Offers advantages, not to mention other amenities and savings.

Those that are developed in the evaporation devices Vapors can be recovered and usable in a special condensation plant Components are processed. Since the evaporation device already consists of these Reason is kept closed, order no odor nuisance nichr.

The applicability of the new process is by no means limited to manufacturing limited by Plie-.lol-. '# idclivdliarzen alone. Rather, E @ can be finite everywhere Advantage to apply where synthetic resins by Uni.e tzun @ any Koinponentcil can be generated. that result in a product, to complete it final evaporation is required. It does not matter whether or not in this evaporation phase. as especially with the Plien0l aldehyde resins, chemical changes take place financially or not. Example i.

A batch of 100 parts phenol, 80 parts formaldehyde, 5 parts Oxalic acid is boiled for about an hour. After sitting down, it will be from the water separated and the liquid mass of the distribution device of a drum dryer continuously fed. The drying roller is heated to about 15o to 16oC. The speed of rotation is to be set so that on the scraper a at approx 8o to go ° C melting, light and almost odorless resin is removed.

When dewatering the reaction mass in the usual Z @ Teise can in particular the odor can never be eliminated in the same perfection. Example '?. A Mixture of crude cresyl alcohols becomes in the molten state (at about 50 ° C) Distributing device fed to a drum dryer. At a roller temperature from about 150 ° C on the scraper device a constant temperature of about 7o to 8o'C melting, almost odorless resin removed, which easily dissolves in alcohol solves.

When cresyl alcohol is processed by the process of patent specification 189262, products either always have a strong smell or are insoluble in alcohol. Example 3.

A mixture of 100 parts of primordial tar phenol, 90 parts of formaldehyde, 5 Share aqueous @ geni ammonia is first boiled for 1 hour. The one separated from the water Reaction product results after leaving the drum dryer; a hard one in the cold, Almost odorless resin with a melting point above 6o'C and good solubility in alcohol.

When processing the approach in the usual way will always be soft persistent, strong-smelling products that dissolve only slowly in alcohol are preserved.

Example .. cresol, formaldehyde and ammonia are in proportion ioo: ioo: in langaineni electricity passed through a long heating coil, its heating It is to be regulated in such a way that the reaction mixture is heated to 100.degree. At the end of A water separator is arranged in the heating coil, from (lein from that freed from: water Liquid Reakticnsprodukt iii a second heating coil, which heating allowed on over ioo'C. The reaction product arrives from this second line The roller on the scraper then becomes the distributor of the drum dryer than one that melts at about 7o to 8o'C, is almost odorless and easily in alcohol Soluble resin mass of resol character (lurking removed. Example. One lets in Mixture of cresol, formaldehyde and condensing agent according to Example 4 by the both heating coils (finite interposed water separator) go and lead then the reaction product obtained to a system of spray nozzles, which are pressed in with Hot air. The finished resin is inside a chimney on a endless belt (expediently made of sheet steel). The removal takes place outside the chamber.

The action of the spray nozzles can sweep through the chamber Hot air flow are supported. In this case, the spray nozzles if necessary, also operate finitely air of ordinary temperature. .

Instead of an endless steel belt, paper to be coated can also be fed into the spray can. Example 6.

To produce a tack-free resin ester, mix at about ioo ' C rosin (100 parts), slaked lime (3 parts) and glycerine (5 parts) and lets the mixture over the heated roller of a drying device to about 25o ° C walk.

The above examples are only intended to illustrate the essentials of the implementation of the @% experience and can of course be changed in a wide variety of ways will.

Claims (2)

PATENT CLAIMS: i. Process for the production of resinous condensation products, in particular those from phenols and aldehydes, - in which the constituents are first made to react, if appropriate in the presence of catalysts, and the reaction product is dehydrated. that only a part of the total amount is always distributed over a coarse surface and in this state is exposed to the brief action of heat. 2. The method according to claim i, characterized (indicates that in the production of @ -on Plicnol-Aldehvdharzen instead of the usual Cresol mixture of ordinary primordial tar phenol is used. 3. "" experienced according to claim i and 2, characterized in that the supply of the reaction components to Evaporation device is continuously designed in such a way that that by switching on a heating device the first reaction of the component possibly with the participation of condensation agents, whereupon the Reaction mixture either immediately or after passing through a watershed is made to evaporate. Method according to claims i to 3, characterized in that that the production of the resin with a processing device for the resin, z. B. a paper coating machine is combined.