DE1150808B - Use of indicator dyes to show the degree of mixing in epoxy resin compounds - Google Patents

Description

Epoxy resins - ζ. B. the glycidyl polyethers of polyhydric phenols - are used in industry for many purposes - as adhesives, coatings, embedding agents and the like. In order to obtain hardenable compounds, i.e. molding compounds, the epoxy resins must be thoroughly mixed _{with a hardener - amines, anhydrides, BF 3 complex.} Insufficient mixing usually results in poor physical properties of the molded parts obtained, such as poor strength and resistance to solvents.

By using indicator dyes to show the degree of mixing of a form, Coating or adhesive, which is an epoxy resin, a hardener and optionally a diluent and Containing fillers, the mixing can be monitored according to the invention.

Particularly suitable indicators are bromothymol blue, Neutral red, ß-naphthol yellow, alizarin or Brilliant yellow.

Although it is known to physically form a yellowish paste with a blue hardener in such a ratio to mix that a mass with a greenish transparent color that comes close to the inherent color of glass Color arises in order to monitor the mixing. It's not one chemically influenced color change. By using indicator dyes one needs on the other hand only a single dye and is no longer of the different basic colors addicted. The choice of dyes that can be used is greater, so too does the inherent color of the reactants can be given greater consideration. The use of indicator dyes is permitted In addition, streak-free mixing in the shortest possible time. The degree of mixing can therefore be significant can be determined more easily. When using indicator dyes, the hardened ones have Mass uniform and improved physical properties, e.g. B. Solvent Resistance, Adhesion and strength.

The dyes used are substantive or acidic dyes and, in particular, substantive dyes based on an aniline salt (e.g. from coal tar). Brilliant yellow, /? - naphthol orange are preferred (Orange II) and alizarin (1,2-dihydroxyanthraquinone). Other dyes that contribute to the color Change contact with the epoxy resin hardener and, if necessary, in the presence of a thinner can be found in indicator tables, e.g. B. Technical Manual and Year Book of the American Association of Textile Chemists and Colorists, Use of Indicator Dyes

to display the degree of mixing

in epoxy resin compounds

Applicant:

Shell

International Research Maatschappij N.V., The Hague

Representative: Dr.-Ing. F. Wuesthoff, Dipl.-Ing. G. Pulse and Dipl.-Chem. Dr. rer. nat. E. Frhr. v. Pechmann, patent attorneys, Munich 9, Schweigerstr. 2

Claimed priority:
V. St. v. America of March 17, 1960 (No. 15 520)

Larry Cecil McGuire, Walnut Creek, Calif.

(V. St. Α.),
has been named as the inventor

Vol. XXXV (1959), pp. 330 to 339 and 317, 330, etc., can be found.

The amount and type of dye used should be such that it will mix thoroughly Components have a clearly perceptible color compared to the color of the unmixed components confers. In many cases, especially in the case of adhesives, other substances can also be in the mixture be present, such as fillers, pigments, other resins and the like, which give the masses a rather dark appearance Give color. In this case a considerable amount of dye must be used in order to obtain a perceptible one Preserve color. In general, about 0.1 to 3 percent by weight of dye will suffice.

Epoxy resins with an epoxy equivalency of greater than 1.0 are preferred.

Particularly preferred epoxy resins are the glycidyl ethers, very particularly the glycidyl ethers of polyvalent ones Phenols and polyhydric alcohols. The glycidyl ethers of polyhydric phenols with a Molecular weight between 250 and 600 and epoxy

equivalences greater than 1.0 come in special because of the superior results one gets with them into consideration.

309 618/29;

3 4

The 33 parts of the reaction product of a dimerized in the molding, coating or adhesive masses

The hardener contained can be the usual alkaline, th linolenic acid and diethylenetriamine and 5 parts neutral or acidic substances. Diethylenetriamine are then mixed with 2 parts of ethylene

Preferred hardeners are the glycol containing hydrogen amine. The mixture obtained is with Compounds, especially the aliphatic or 5 at a rate of about 50 μ / min so gecycloaliphatic Amines and the amine hydrogen stirs that thorough mixing of the components containing amides. he follows. After about 3 minutes it will change

If the indicator dye is not deep red, or if the color of the mixture is poor, there are no streaks soluble in the epoxy resin and the hardener, so streaks of uncolored or slightly colored can add an additional substance to the mass, the io tem material is more present,
the dye dissolves and intimate contact between the resulting molding compound can then be used as an adhesive

the indicator and the hardener allowed. Such fabrics are used to join two pieces of aluminum liquids such as phenols and complex amines are used against each other. The glycols ge at 24 ° C, Chloroform, ether and monoepoxides. hardened bond has excellent strength

These substances not only improve solubility and are superior to similar bonding of the indicator dye in the reaction mixture, according to the usual method of stirring in the but also reduce the viscosity of the form hardener without specifying the degree of mixing. was asked.

Various other substances can be added to Example 2

Giving form, coating or adhesive, e.g. B. 20

various fillers, such as asbestos, aluminum, aluminum Example 1 is repeated with the exception that

Minium oxide, iron oxide, sand, pigments, plasticizers are used as epoxy resin, polyether C - from the USA patent maker, other polymers such as formaldehyde resins, writing 2,633,458. Similar furfural resins, polyacetal resins, polyvinyl resins, chewing results are obtained,
chuke. 25th

The examples 3 listed above are preferably mixed

Components, the epoxy resin filler or the fillers and the indicator dye, these Examples 1 and 2 being repeated with the mixture then with a mixture of that one would take brilliant yellow through each of the following hardeners and diluent is combined. The 30 replaced the indicators: yS-naphthol yellow (Orange II), However, the order in which they are added is not decisive alizarin, neutral red, bromothymol blue (dibromo- and can be changed if necessary. thymolsulphophthalein). In doing so, similar

Mixing is continued until the results are obtained.
The color of the mixture is uniform throughout and example 4

has reached the desired shade. The 35

If necessary, the desired color shade can be determined in advance. 65 parts of polyether A are matched with 20 parts of quartz by mixing some routine powder and 0.5 part of Brilliant Yellow. then Moods are carried out and the tone comes from 35 parts of the polyamide resin from Example 1 the required physical properties with the added. After 2 minutes of stirring the color is hardened molding supplies. 40 deep red, without stripes or streaks. For the production

The hardening of the mass can be done in the case of spatial or molded parts, the mass is poured into molds higher temperature depending on the one used and hardened at 40 ° C. It becomes a homogeneous one Harder, done. Fitting included.

Unless otherwise stated, "parts" means in For such a mixture was without brilliant yellow

the following examples are parts by weight. 45 so far to ensure the correct through

mixing degree a mixing time of 5 minutes is necessary.

Claims (1)

PATENT CLAIM: 100 parts of U.S. Pat. No. 2,633,458 Use of Indicator Dyes as mentioned Polyethers A are made with 50 parts. powdered aluminum as a filler and 25 parts of coating or adhesive, which is an epoxy resin, Asbestos mixed. 0.7 parts of a noun coloring - a common hardener and possibly also substance based on aniline salt, brilliant yellow (contains thinners and fillers. made by conversion of phenol with doubly diazo diaminostilbene sulfonic acid) is added 55 Publications considered: and stirred the mixture. There is no color change. Company font: Habilit der Firma Henkel & Cie. change a. GmbH., Düsseldorf. © 309 618/291 6.63