DE1911478C - Process for the production of epoxy polyadducts - Google Patents

Description

R,

R-,

R,

R,

in the R ₁ . R, and R ₃ alkyl-. Cycloalkyl aryl. Alkaryl or arylalkyl radicals each having not more than 25 carbon atoms and R _{4 is} an alkaryl radical 2- having 1 to 10 carbon atoms and X is a halogen atom.

2. The method according to claim 1, characterized in that the PhnNphoniumhalogenid Triphenylalkylphosphonium halide is used.

3. The method according to claim 2, characterized in that that triphenylalkylphosphonium iodide is used as the phosphonium halide.

4. The method according to claim 3, characterized in that the phosphonium halide is used Triphenyläthylphosphoniumjodid used.

5. The method according to claim 1 to 4, characterized in that the phosphonium halide in an amount of 0.001 to 10 percent by weight, based on the reactants used.

It is known that polycarboxylic anhydrides for curing polyepoxide compounds at increased Temperature can be used. The polycarboxylic anhydrides react with the polyepoxide compounds very slowly, even at elevated temperatures, which means long curing times. Accelerators, such as tertiary amines, are therefore usually added in order to reduce the hardening time will. The mixture of polyepoxide compounds. Polycarboxylic anhydrides and accelerators are said to be have a usable pot life so that sufficiently large batches of the mixture can be poured. to form and impregnation can be provided.

It is also known to use organic phosphines as curing accelerators in the manufacture of adducts to use from polyepoxy compounds and polycarboxylic anhydrides. However, these have the disadvantage that the mixtures are cured very quickly even at room temperature, so that the Use of the phosphines would lead to insufficient pot life of the approaches.

The invention relates to a process for: Production of polyadducts by reacting with -.Alkar \ i-

Halogen atom means

S £ * the inventive method is he, Room temperature a satisfactory pot life and be, eSr temperature a very fast curing of mixtures of Poiyepox.dverb.andungen and Pohcarbonsäureanhvdnden achieved.

The m methods of the invention used Accelerators have the additional advantage that

- Maintain reliable activity over a long period of time if we are dissolved in a pohepoxide compound and if other catalysts "change the poly-epoxide compound, e.g. by gelling. This makes it possible to produce storable ^ -

3, to produce catalyzed pol> epoxy compounds to which only the polycarboxylic anhydride was added must become. a hardenable mixture », w.

ii have epoxy polyadducts _; > r-

raoencfe mechanical properties and show καηο vJrrarbunc.The method according to the invention.std.ncr for the production of coatings. Pouring hangings. I-oim bodies and laminates are very suitable.

The ones used in the method according to the present invention 4S poly epoxy compounds are compounds that "on average more than one vicinal epoxy group. d. H. more than one group

he molecule contain. Preferred polyepoxy compounds

5, dunaen are liquid polyglycidyl ethers of 2,2 bis

(4-hydroxyphenydpropane. Such liquid poly-

Glycidyl ethers are usually made by reacting

from "> -). Bis (4-hydroxyphenyl) propane with a large

Excess of epichlorohydrin in the presence of a

Alkali hydroxide produced and usually own

Epoxy equivalent weights from 170 to 250.

Other polyepoxy compounds which may be used are polyglycidyl ethers of solid ■> •> bis (4-hydroxyphenyl) propane as derived from the dihydric phenol 'and epichlorohydrin in molar ratios of 1: 1.1 to 1: 2 in the presence of alkali metal hydroxides can be produced, as well as polyglycidyl ethers from novolaks and resoles, poly-

glycidyl ether of polyhydric alcohols, such as glycerine. Pentaerythritol and trimethylol propane. Glycidyl esters of polybasic acids such as diglycidyl adipate. Diglycidyl tetrahydrophthalate and dielycidyl hexyhydrophthalate. Compounds having inner poxygruppen ^r. such as 3.4-epoxy-cyclohexylmethyl-3.4-epo \ ycyclohexanoate and mixtures of such epoxides.

The polyepoxide compounds can be used in a known manner Use a smaller amount of 3 to 20 percent by weight of a liquid monoepoxide. like Buty IgIyeidyläther. Phenyl glycidyl ether. OctylglycidyUither or a glycidyl ester of a monocarboxylic acid contain. Such reactive diluents are preferably used together with viscous liquids Epoxy compounds used to reduce their viscosity.

Examples of polycarboxylic anhydrides. that can be used are

Phthalic anhydride.

Tetrahydrophthalic anhydride.

Hexahydrophthalic anhydride.

Succinic anhydride.

3.4.5.6.7.7-Hexachlor-3.6-endomethylene-

l.H-tetrahydrophthalic anhydride-chlorine-

endic acid anhydride).
Dodecenyl succinic anhydride.
3.6-endomethylene tetrahydrophthalic acid

anhydride.
Methyl ^ .o-endomethylene-tetrahydrophthal-

acid anhydride.
Trimellitic anhydride.
Polyazelaic anhydride.
Pyromellitic dianhydride.
Benzophenone-S ^ J '^' - tetracarboxylic acid-

dianhydride.
partial esters of glycol or glycerol with trimellitic anhydride and mixtures of such compounds.

Preferred polycarboxylic anhydrides. which can be used according to the invention are usually liquid or low melting anhydrides such as hexahydrophthalic anhydride.

The catalysts used in the process according to the invention are phosphonium halides in general Formula:

R ₁

[X]

in which X is a halogen atom, such as chlorine, bromine or iodine, R ₁ . R ₂ and R _{3 are} identical or different monovalent alkyl, cycloalkyl, aryl, alkaryl or arylalkyl groups with not more than 25 carbon atoms each, preferably with 1 to 18 carbon atoms, e.g. B. phenyl, butyl, octyl, lauryl, hexadecyl or cyclohexyl groups and R _{4 is} an alkyl group with 1 to 10 carbon atoms, such as a methyl, ethyl, propyl, η-butyl, sck.-butyl and mean n-decyl group.

Examples of phosphonium halides. which are useful as catalysts according to the invention are Methyl triphenylphosphonium iodide. Ethyl-iriphenylphosphonium iodide, Propyl triphenylphosphonium iodide. n-Butyi-triphenylphosphonium iodide. ii-decyl triphenylphosphonium iodide. Methyl - tributylphosphosnium iodide, ethyl triphenylphosphonium chloride. η - butyl - triphenylphosphonium chloride and Äthvltriphenyiphosphoniumbromid. Preferred phosphonium halides are triphenylalkylphosphonium halides.

These phosphonium halides can generally be prepared in that approximately equimolar Amounts of a phosphine of the general formula

R ₁ -PR ₃

be mixed with a halide of the general formula R ^ X, where in the formulas R ₁ . R _:. R ₅ . R ₄ and X have the meaning mentioned, after which, if appropriate, in the presence of an inert solvent such as diethyl ether. Benzene. Chloroform or carbon tetrachloride, the mixture is heated.

To explain the method of production of the phosphonium halides For example, ethyl triphenylphosphonium iodide is prepared as follows: 52g triphenylphosphine are dissolved in ICK) ml of benzene and slowly added 32 g of ethyl iodide. The mixture will Heated under reflux for 4 hours and the white precipitate filtered off and dried. It will 63 g of ethyl triphenylphosphonium iodide of melting point 161 to 162 C.

In the process according to the invention, the equivalence ratio of the polycarboxylic acid anhydride is to the polyepoxide compound in the range commonly used, d. H. from G.o: 1 (for chlorinated polycarboxylic anhydrides) to 1.1: 1. In the case of diacid anhydrides, the equivalence ratio is preferably 1: 1. With polycarboxylic acid anhydrides referred to the equivalent weight is the molecular weight divided by half the number of potential carboxyl groups. In the case of polyepoxy compounds, the equivalent weight is determined by determining the epoxy groups definitely.

The catalysts are only required in very small quantities. Excellent results are obtained when the catalyst is used in amounts of 0.001 to 10 percent by weight, based on the reaction

^ o taker, is used. Particularly preferred amounts are from 0.05 to 5 percent by weight based on the reactants.

When carrying out the method according to the invention, different per se can be used for different Purposes known additives are used, such as volatile solvents, non-volatile solvents, Pigments, fillers, other resins. Fiberglass, asbestos. Sand and other finely divided minerals, asphalt. Tars, stabilizers, insecticides, dyes. Plasticizers and the like. Solid polyepoxide compounds can be melted before the polycarboxylic acid anhydride, the accelerator and optionally other additives can be added.

The hardening and adduct formation is achieved by heating the ingredients to temperatures above Room temperature accomplished. Excellent cure speeds are achieved at temperatures from 50 to 200 ° C, which is why this temperature

1 91 i 478

area is preferred in many applications. Temperatures well above 200 C are generally not desirable, but can be used if necessary.

The mixtures of polyepoxy compound. Hardening «» - Agent and catalyst can be used for many important purposes.

You can use Pur Metall as adhesives, for example. Hol /. Concrete. Plaster of paris and the like and used as a surface coating for various types of surfaces. They can also be used to make laminates or artifacts. reinforced with textile fibers are used. Also -.ic can be used for the production of castings and moldings! ": Ι: ·. \ Ύ / to encapsulate electrical devices.

The following examples will help you find the answer naiK: explained.

example 1

For 100 parts by weight of technical Diglvcidvi : From 2.2-bis (4-hydrox) phen \ /! propane with 0.52% epoxide equivalents per 100 g mil XO parts by weight of hexane drophthalic anhydride and 0.16 parts by weight Athvltriphenvlphosphoniurniodid (TPPFl) mixed-Ha-. The mixture was hardened at 125 ° C. for 2 hours to form a molded article used for measurement the physical properties was used. The properties of the adduct are as follows Table I listed in column 1. For comparison was a similar mixture using 1 part by weight 100 faces each of the approach Ben /> F dimelhylamine (BDMA) as a catalyst / u GieLUingen hardened, the properties of which are listed in table i under column 2.

Tab

II ¹ Pi.I ill ΒΠΜ

Tensile strength, kg cnr 522 "2i until / at break M> 0.2 ",. To / at setting Elongation at break. ",. '.93 3. bi> / to break 35 420 ! 0.2 "" to / at setting ! 2SS 2s wiO Train modes. kg cnr 3 "Wed (I I ί <> ¹ ) Flexural strength, kg cnr read; 32 4Ki BlCÜOni'iJul. kg CiI ":" know clearly Ge! r 1-arbc

Example 2

; o This example explains the effect of a «· i'h ■ > phoniumhaliigenid.-aiii the pot life and the dd:, runas / eit of the mixture of a Fpoxidverbindt.iu and a Puhcarbons.iureanhydnd. lOOGewich; - ieile of the Dighcidjlather-. from 2.2-Bisi4-h_vdro \> p! v.

nvlipropan. as in the example] use it! wi: ide. were with HO parts by weight of hexahydrophthalic, urcanhydride and 0.1 part by weight of ethyl triphenylph phonium iodide (TPPFIi \ ermi «-cht. The experimental results ness of pot life and gelation / ci:

ic are given in the following table, where zuiv, compared to the same < κ-mixture with benzyldimethylamine (BDMA!) was used as the hardening accelerator, which is currently due to the good latitude in mixtures of epoxy compounds u: ni

; s carbonic acid anhydride catalyst used; - '

TPPFI | 0.1 percent by weight). . .
BDMA ") (0.05 (weight percent).

table II : Tap ii.iu: na ^ h : Ir · " \, ^ • Itcrun. ^. » ' X " ^ Γ. _ΐμι π Z; Mii'.uIlt, · ¹ ! I) T.iuei! X-V Y ! Z-Z. 16 W. Y 38: \ ^T

Ί (icmcssen at Ki5 (. '.

Ί Β [) Μ · \ was in jcr same Molkon / entr ^ lion v- \ c ΓΡΡΓ.Ι \ eruemlel

The data show that the phosphonium halide is more reactive than BDMA with respect to the gelation tower time the same molar concentration and with regard to the pot life the BDNfA etvwi tileiclnvertii; is.

Claims (1)

Palent claims: 1. Process for the production of Poh adducts by reacting with shaping of epoxy compounds with an average of more than one epoxy group per molecule with poly carbon ^ .tureanhydrides at elevated temperature in the presence of a phosphorus compound as an accelerator, thereby characterized in that a phosphonium halide is used as the phosphorus compound general formula: aroLus phosphorus compound as Ä ⁿ u "? 4f that 'dadu ^ e chin is drawn that as a phosphorus compound a Phosphomumhalosemd of the general formula: