DE1052117B - Process for the production of copolymers from epoxy resin esters and aromatic vinyl compounds of high value for paint technology - Google Patents

Description

The invention relates to the production of copolymers from epoxy resin esters and aromatic ones Vinyl compounds, especially styrene.

The epoxy resins are glycidyl ethers of dihydric phenols as described in the British patents 680 997 and 681 001 and by heating a dihydric phenolic compound with epichlorohydrin at temperatures of 50 to 200 ° C in the presence of a base can; by changing the proportions between epichlorohydrin and dihydric phenol A variety of products with different molecular weights are available.

It is known that styrenated esters of fatty acids can be used from drying and semi-drying oils with the epoxy resins mentioned, made by means of an A ^ process, which is based on the production of an ester the epoxy resin and its reaction with styrene is stopped; this procedure is used in. the German Patent Specification 950 870 or in US Pat. No. 2,596,737 on which it is based. The reworking of the process has shown, however, that although good results in terms of viscosity and the homogeneity of the product and its compatibility with urea and melamine-formaldehyde resins can be achieved if one starts from the epoxy resins with lower molecular weight (As with a ratio of 1.65 to 1.75 or more molecules of epichlorohydrin per molecule dihydric phenol); the use of resins of higher molecular weight (molecular ratio Epichlorohydrin to dihydric phenol about 1.25 to 1.35: 1 or less) as described below the trade name "Epikote" ("Epikote 1004", "Epikote 1007" or "Epikote 1009") are known however, to highly viscous or even gelatinous substances that are not always homogeneous and that contain carbonyl-aldehyde type curable resins such as urea and melamine-formaldehyde resins have good or no tolerance at all. Some of these high molecular weight epoxy resins are so reactive that even during esterification, i. H. before attempting any To styrenate esters, gelling occurs, whereby of course the temperature and temperature used the type and amount of fatty acid esters used play a role. For example, “Epikote 1004 "(45 parts) when reacting with a mixture of fatty acids from dehydrated castor oil (11 parts) and from sunflower oil (44 parts) at 260 ° C during cooking, d. H. before the esterification was complete. However, if the esterification was carried out at 230 ° C., it was successful Ester with an acid number of 15.7 from the same reaction

for the production of lacquer technology, more valuable

Copolymers of epoxy resin esters and aromatic vinyl compounds

Applicant:
Lewis Berger & Sons Limited, London

Representative: Dr.-Ing. F. Wuesthoff, Dipl.-Ing. G. Pulse and Dipl.-Chem. Dr. rer. nat. E. Frhr. v. Bad luck man,

Patent Attorneys, Munich 9, Schweigerstr. 2

Great Britain November 24, 1954
and November 10, 1955

Frank Armitage, Chingford, Essex,
and William Eric Allsebrook, Borrow Ash, Derbyshire

(Great Britain),
have been named as inventors

Prepare a mixture. Styrene, to which a catalyst was added, was slowly added to a 75% strength Solution of this ester in xylene occurred after 3 hours Heat a gelling one. In another attempt at copolymerization succeeded in preventing gelling during the reaction by using a little dipentene (in addition to the xylene), however, the film obtained from the product was cloudy. Another styrenated ester made from a linseed oil fatty acid ester of. "Epikote 1004" also showed intolerance as a film. Another Esters with a content of sunflower fatty acidii (78%) and the fatty acids of. dehydrated castor oil (32%.) gelled when in its solution in Xylene was added dropwise to styrene, and likewise when a mixture of the ester and styrene was used as Whole was catalytically reacted in xylene solution.

From the German patent specification itself or the USA patent specification 2 596 737 it can be seen that this process leads to products of high viscosity (which is equivalent to the formation of relatively small film thickness with spray consistency) and that these are of dubious clarity. For example, in an intermediate polymer described in the patent, a low

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the hit that won't dissolve again if not a sufficient excess of xylene, reducing the solids content to up to 30%, is added. In relation on another interpolymer described in the patent it is stated that it is necessary remove "gel-like particles" from it by filtration. Filtration of the Reaction mixture as necessary, either to remove gel-like particles or to make them clear Solution to come. In one case, double filtration is even mentioned. There is no special one Indication of whether the films were clear or not, and even though viscosities are not given, works from the text it emerges that in view of the relatively low solids content of the solutions used for Applying with the spatula had been used, the viscosities must be high, quite apart from that from the presence of the "gel particles" mentioned.

According to the invention has now been found that one can come to homogeneous products with good Viskositätseigenschäften when esterifying the epoxy resins of higher molecular weight with previously styrenated fatty acids and or or when the \ ^r eresterungs- and Styrolisierungsreaktion performs simultaneously.

According to the invention there is a process for the production of copolymers from the epoxy resin esters of fatty acids from drying or semi-drying oils with aromatic vinyl compounds in that one can be obtained by reacting epichlorohydrin with a dihydric phenol in a ratio Epoxy resin made from less than 1.4: 1 with one or more fatty acids more drying or semi-drying oils esterified, these fatty acids being used before or during the esterification reaction copolymerized with an aromatic vinyl compound. The aromatic vinyl compound is preferable an aromatic vinyl hydrocarbon such as styrene including the ring alkylated and im Core halogen-substituted styrenes, such as vinyl toluene.

It is possible to use urea and melamine-formaldehyde resins with lower levels of fatty acids in the ester compatible products to come; these resins are desirable additives in the Manufacture of thermosetting (oven-drying) paints. There is a reference in the literature ensure that the styrenated epoxy resin esters are compatible with urea or melamine-formaldehyde resins are still on how such compatibility can be achieved. If the tolerability Styrenated epoxy resin esters with such resins also differ from the incorporated ones to a certain extent Depends on the amount of styrene and is the greater for an eponester of a certain oil content, the lower the proportion of copolymerized styrene, the proportions seem to be that with an incorporated styrene content of up to 30% (measured on the basis of the final Resin, d. H. the total weight of the reagents) compatibility with melamine and urea-formaldehyde resins can only be achieved if the proportion of total fatty acids in the end product is less is than 40%, d. H. if this proportion is less than 40% of the total weight of the reactants represents.

The styrenated fatty acid esters to be used according to the invention can be used in accordance with the British Patent 611 109 described method or a modification of such methods produced will.

The following examples serve to explain the invention in more detail, the percentages being percentages by weight mean. The used. Epoxy resins are those with a higher molecular weight (Moiverratio Epichlorohydrin to dihydric phenol about 1.25 to 1.35: 1 or less), as described under the Trade name "Epikote" are known, and the mentioned Synourin fatty acids "S" are fatty acids made from dehydrated castor oil with a viscosity of 0.5 poise.

example 1

50O ¹ g of fatty acids from dehydrated castor oil (viscosity 0.5 poise) (Synourin fatty acids "S") were heated in a 2-1 flask with 100 g of styrene, the temperature at the reflux condenser within half an hour of. 220 to 260 ° C rose. ^{105O 1} g of styrene was then added dropwise over 13 hours, the temperature being maintained between 23O ¹ and 260 ° C .; the reaction mixture was then held at 260 ° C. for a further 4 hours. The product was a pale yellow paste with 96.2% nonvolatiles. A water separator was used to separate out a small amount of water that would otherwise have caused "spattering".

A mixture was then prepared from 450 g of the styrenated fatty acids prepared as above, 284 g of fatty acids from sunflower oil, 280 g of "Epikote 1004" and 50 g of xylene, heated to 245 ° C. and the water of esterification was removed using a Dean and Stark separator. The reaction was continued at 245 to 265 ° C. for 9 hours until an acid number of 9.5 was reached. The viscosity was 3.7 poise at 49.5% solids "in xylene. The product gave a Idaren film and was compatible with 10% melamine-formaldehyde resin substantially, but not more ^30!%.

Example 2

151 g of styrenated fatty acids according to Example 1, 265 g of fatty acids from sunflower oil, 128 g of synourin fatty acids "S", 360 ^! g of "Epikote 1004" and 60 g of xylene were mixed, heated to 245 ° C. and, as in Example 1, brought to an acid number of 9.0 and a viscosity of 4.3 poise in xylene at 51% solids within 8 hours. The product gave a clear film, but was somewhat less compatible with melamine-formaldehyde resin than the product from Example 1.

Example 3

455 g of styrenated fatty acids according to Example 1, 212 g of fatty acids from sunflower oil, 350 ^! g of "Epikote 1004" and 90 g of xylene were _{kept at 245 ° C. for 9V for 2} hours and, according to Example 1, brought to an acid number of 6.6 and a viscosity of 4.6 poise at 52% solids in xylene. The product gave a clear film and was well compatible with 30% melamine-formaldehyde resin.

A mixture of the product of Example 3 with melamine-formaldehyde resin (30% of the dried film weight of resin) was sprayed onto a metal sheet and V2 hour at 150 ^| thermoset ⁰ C. The rocker hardness was 53 and the total hardness was 1600 g, in contrast to 42 or 1200 g for a typical unstyrenated epoxy resin ester / melamine-formaldehyde resin product with 40% oil. The kinkability, as measured by bending over a 3/4 inch mandrel, was satisfactory.

Alkali resistance tests at 80 to 85 ° C for 18 hours against 0.6% trisodium phosphate solution gave the same results as with the product made from unstyrenized epoxy resin ester / melamine-foTmaldehyde resin.

Example 4

455 g of styrenated fatty acids according to Example 1, 212 g of Synourin fatty acids "S", 350 g of "Epikote 1004" and 90 g of xylene were reacted at 260 ° C. for 10 hours, resulting in an acid number of 9.4 and a viscosity of 3.9 poise at 51% solids in xylene. The product itself gave a clear one Film and was compatible with melamine-formaldehyde resin.

Examples 3 and 4 illustrate styrenated epoxy resin esters in which the fatty acid content is less than 40%.

Example 5

175 g "Epikote 1004", 145 g fatty acids from sunflower oil, 30 g synourin fatty acids "S" and 13 g dipentene were mixed and placed in a vessel equipped with a Dean and Stark separator. Heated 250 ° C, whereupon 159 g of styrene were added at such a rate that the temperature remained constant. ^{11 cm 3 of} water was separated out in 6 hours and found that about 95% of the styrene had been copolymerized.

The product had an acid number of 5.0 and a viscosity of 1.3 poise at 51% solids content Xylene and was both in solution and in the form of a thermoset film with commercially available melamine-formaldehyde resin (Beetle 615) in a ratio of 6 parts ester to 4 parts resin compatible.

Example 6

252 g "Epikote 1007", 150 g fatty acids from sunflower oil, 50 g synourin fatty acids "S" and 21 g dipentene were heated together to 230 ° C in the device according to Example 5, whereupon 113 g styrene were added over 6 hours and 12 cm ^{3 of} water were withdrawn. The product had an acid number of 5.0 and a viscosity of 1.4 poise at 40.5 percent solids in xylene solution. It was well compatible with melamine-formaldehyde resins.

Example 7

252 g "Epikote 1007", 150 g fatty acids from sunflower oil, 50 g synourin fatty acids "S" and 21 g dipentene were heated to 235 ° C. in the device according to Example 5, whereupon 113 g vinyl toluene were added over 5 hours and 11.5 cm ³ waters were deposited. The product had a viscosity of 1.6 poise at 41.4% solids in xylene and was well compatible with melamine-formaldehyde resins.

Example 8

210 g fatty acids from sunflower oil, 70 g synourine fatty acids "S", 353 g "Epikote 1007" and 272 g Styrene.

A mixture of the above fatty acids was heated to 240 ° C. and 113 g of the styrene were slowly added at this temperature. The 353 g of "Epikote 1007" were then added, whereupon the remaining 141 g of styrene were added at such a rate that the temperature remained constant at 240 ° C. The separated water (15.3 cm ³ ) was collected in a water separator and the experiment was over in 8 hours. All of the styrene had been added during the first 6 hours and the temperature was maintained at 240 ° C for the last 2 hours by adding a small amount of xylene.

The product exhibited an acid number of 7.1 and a viscosity of 3.7 poise at 43.5 percent solids in xylene. By adding melamine-formaldehyde resin to this resin, hard, clear, thermosetting can be produced Make paints.

ίο According to Example 8, higher styrene proportions are copolymerized than according to Examples 5 and 6, and when using the "Epikote 1007" resin, which has a higher molecular weight, it has been found to be advantageous to first copolymerize part of the styrene with the fatty acids and then a one-step To join processes in which the remainder of the styrene comes to reaction, as can be seen from the last example.

The use of a small proportion of dipentene, as shown in Examples 5, 6 and 7, facilitates the production of a stable product, but the dipentene is not an essential component. Small amounts of others can also be used to aid in the removal of the water of esterification Solvents can be used when all of the styrene is copolymerized before esterification is complete is; however, the use of a solvent is by no means necessary, and the monomeric Styrene, which is present during the reaction, can be considered reliable for the formation of an azeotrope with the water, which is removed in this way from the reaction mixture.

From the foregoing description it can be seen that the invention consists in a method which enables the production of clear styrenated epoxy resin esters, some of which with urea and melamine aldehyde resins are compatible. The basis for the copolymers are the epon resins higher Molecular weight, from which clear products are otherwise not at all or only under Let difficulties get in.

Claims (6)

Patent claims: 1. Process for the production of lacquer-technically valuable copolymers, in addition to epoxy resin esters (i.e. the esters of the fatty acids of drying or semi-drying oils with a condensation product from dihydric phenols and epichlorohydrin) an aromatic vinyl compound contain, characterized in that a condensate containing less than 1.4 moles of epichlorohydrin contains per mole of the dihydric phenol, drying with one or more fatty acids or semi-drying oils esterified before or during the esterification with an aromatic Vinyl compound, preferably styrene or a core alkyl or halogen substituted styrene, are copolymerized. 2. The method according to claim 1, characterized in that there is no more than esterification 40% of the total weight of the reacting substances is used in fatty acids. 3. The method according to claim 1 and 2, characterized in that the amount of the aromatic vinyl compound present in the reaction mixture does not exceed 30% of the total weight of the reacting substances. 4. The method according to claim 1 to 3, characterized in that the aromatic vinyl compound is added to the esterification mixture in several portions during the esterification. 5. The method according to claim 1 to 4, characterized in that the aromatic vinyl compound introduced to a certain extent as a copolymer with the fatty acids in the reaction mixture and the rest during the Esterification is added in free form. 6. The method according to claim 1 to 5, characterized in that one is used for esterification Mixture of the free fatty acids and their copolymers with the aromatic vinyl compound used. Considered publications: German Patent No. 915 870;
U.S. Patent No. 2,596,737. © «09 768/560 2.59