CH643577A5 - Process for the preparation of curable adhesives or sealants, and the use thereof for the production of adhesive bonds and seals - Google Patents

Description

The invention relates to a process for the preparation of curable adhesives or sealants, which is a curable reaction product with ester groups of the formula

R "

I.

CH2 = C-COO-

where R "is a hydrogen or chlorine atom, or a methyl or ethyl group, in a mixture with at least one further component, and their use for the production of bonds and seals between surfaces.

It is known that solidifiable resins which have desirable properties can be prepared as a reaction product of an organic polyisocyanate with an acrylic acid ester which has a reactive hydrogen atom in the molecule. Such resins are known from U.S. Patent 3,425,988 to Gorman. This patent specifically relates to monofunctional substances with terminal acrylate groups which are reacted with organic polyisocyanates in such a ratio that all isocyanate groups are converted into urethane or ureide groups. The esters are preferably the acrylic acid and methacrylic acid esters which contain functional hydroxyl or amino groups in the molecule.

US Pat. No. 3,678,014 to Suzuki discloses a thermosetting resin which is stabilized with peroxide and which is a reaction product of a polybutadiene or copolybutadiene, which consists predominantly of butadiene units of the 1,2 configuration and with hydroxyl or carboxyl groups is blocked, with an isocyanate compound, which was obtained by reaction of an organic polyisocyanate with an olephenic compound, such as acrylic acid hydroxyl alkyl ester or methacrylic acid hydroxyl alkyl ester. The resins thus produced can be cured with peroxy initiators and are said to be usable as coatings and adhesives. However, such resins are not entirely satisfactory in terms of various properties such as e.g. Impact resistance and thermal strength (i.e. the strength at high temperatures or after heating to high temperatures), and furthermore they do not have the ability to perform satisfactorily in relatively large gaps e.g. to hold about 1-1.3 mm or more.

From U.S. Patent 3,431,235 to Lubowitz, the ring formation (formation of a cyclic compound) of a reaction product of e.g. known with hydroxyl-substituted 1,2-polybutadiene with tolylene diisocyanate. Although this leads to some useful properties, the heat resistance and hardening speed and also the hardening with a larger volume are insufficient.

It was an object of the present invention to provide curable mixtures of adhesives or sealants which give bonds and seals between surfaces with improved thermal and impact resistance properties and also hold in gaps of more than 1 mm in width.

This object is achieved by the im

3 643577

Claim 1 characterized method for the production of curable adhesive or sealant mixtures and solved by the use characterized in the independent independent claim 23.

s Advantageous embodiments of the invention are shown in the dependent claims.

The invention is explained in more detail below with the aid of examples.

The reaction products produced according to the invention as a mixture component can be regarded as polymerizable one-component block copolymers which have rigid and flexible segments. This is achieved by chemically linking two «prepolymers», which are then combined with functional acrylate groups, e.g. Methacrylate groups are capped. Accordingly, in a preferred embodiment, a "flexible" polymeric or copolymeric butadiene diol segment of relatively low molecular weight with an isocyanate equivalent 20 excess of its hydroxyl equivalent of a "rigid" diisocyanate, such as e.g. Toluene diisocyanate or methylene diisocyanate (diphenylmethane-4,4'-diiso-cyanate), reacted, whereby urethane bonds are formed. Before the reaction with the butadiene polymer or copolymer, the diiso-2s cyanate is preferably reacted in excess with another radical which contains "stiff" in hydroxyl or non-tertiary amine groups at least two reactive hydrogen atoms, the other "stiff" residue is capped with 0 = C = N groups. The term “rigid” segment means a segment or segments that contain aromatic, cycloaliphatic or heterocyclic rings. If a plurality of segments are involved, then these should either be in the form of condensed or directly combined rings or be connected by a minimal number of carbon atoms (for example 1 to 2 in the case of longitudinal chaining or 1 to 6 in the case of crosslinking) or heteroatoms, so that there is little or no flexibility between the segments. The term “flexible” segment means a segment that primarily comprises linear aliphatic parts with internal unsaturated points. Attached functional groups, including Aromatic, heterocyclic and cycloaliphatic groups, also as cross-members, can also be included, provided that there is no significant impairment of the required flexible nature of the linear part.

Examples of the polyisocyanates that can be used in the preparation of the adhesive or sealant mixtures according to the invention include the following so-called: phenylene diisocyanate, tolylene diisocyanate, diphenyl 4,4'-diisocyanate, diphenylmethane 4,4'-diiso-cyanate, dianisidine diisocyanate, naphthylene-l, 5-diisocyanate, diphenyl ether 4,4'-diisocyanate, p-phenylene diisocyanate , Dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis (isocyanato-55 methyl) -cyclohexane, cyclohexylene diisocyanate, tetrachlorophenylene diisocyanate, 2,6-diethyl-p-phenylene diisocyanate and 3,5-diethyl-4,4 'diisocyanate diphenyl methane. Other polyisocyanates that can also be used are the rigid, higher molecular weight polyisocyanates, which are obtained by reacting polyamines having terminal primary and secondary amine groups or polyhydric alcohols, e.g. the alkane, cycloalkane, alkene and cycloalkene polyols, e.g. Glycerin, ethylene glycol, bisphenol-A, 4,4'-dihydroxyphenyldimethylmethane-substituted bisphenol-A and the like can be obtained with an excess of one or more of the above-mentioned isocyanates. These higher molecular weight urethane or ureide polyisocyanates can be represented by the formula

643577

H O

I II

(0 = C = N-R-N-C-X-) n-B

in which R is an organic radical from the group comprising alkyl, alkenyl, cycloalkyl, cycloalkenyl, aryl, aralkyl and alkaryl radicals having 2 to 20 carbon atoms, both substituted and unsubstituted substituted; X is in the formula above

R '

I.

-O- or -N-, where

R 'is hydrogen or a lower alkyl group of 1-7 carbon atoms; B in the above formula is a polyvalent organic radical from the group comprising cycloalkyl, cycloalkenyl, aryl, aralkyl, alkaryl, and heterocyclic radicals, both substituted and unsubstituted; In the above formula, n is an integer from 2 to 6.

As already stated above, the diisocyanate is preferably reacted with another rigid segment which comprises an aromatic or cycloaliphatic compound with at least 2 reactive hydrogen atoms, preferably diamines and more advantageously diols. Suitable compounds include 2,2- (4,4'-dihydroxyphenyl) propane (ie bisphenol-A), 4,4'-isopropylidendicyclohexanol (ie hydrogenated bisphenol-A), ethoxylated bisphenol-A, propoxylated bisphenol-A , 2,2- (4,4'-dihydroxydiphenyl) butane, 3,3- (4,4'-dihydroxydiphenyl) pentane, a, a '- (4,4'-dihydroxydiphenyl) -p-diisopropylbenzene , 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,4-cyclo-hexanedimethanol, bicyclic and tricyclic di-oils such as 4,8-bis (hydroxymethyl) tricyclo (5.2.1.02-6) -decane, 2, 2,4,4-tetramethyl-l, 3-cyclobutanediol, hydroquinone, resorcinol and 2,2- (4,4'-dihydroxydiphenyl) sulfone, as well as the halogenated derivatives of the above compounds such as tetrabromated ethoxylated bisphenol-A. These ring compounds can also be substituted with reactive or non-reactive groups, such as, for example, alkyl groups with 1 to 4 carbon atoms. This reaction can be carried out at temperatures from room temperature to 180 ° C., preferably in the temperature range from 40-120 ° C., the temperatures depending in particular on the specific reactants selected. Conventional catalysts can be used at lower temperatures. Non-reactive diluents can be used if desired.

The organic or the polyisocyanate obtained as the reaction product is reacted with a polymeric butadiene compound which has a functional group at each end of the butadiene chain which contains a reactive hydrogen atom, preferably a hydroxyl group.

The molecules of the butadiene polymers or copolymers used in the present invention predominantly contain butadiene units in a specific configuration, namely the 1,4 configuration.

It is generally known that 1,3-butadiene can form a polymeric chain according to one of the following two structures: the 1,2-form, resulting in contiguous reactive groups of the following formula,

CHz-CH-

I.

CH

. II

CH2

or the 1,4-form, resulting in a linear unsaturated chain of the following formula:

- (CH2-CH = CH-CH2 ^ -.

s

The 1,2-form has long been recognized to be useful for the manufacture of adhesives. In contrast, the importance of the 1,4-form to achieve significantly better properties has not yet been recognized. The present invention requires that the butadiene polymer or copolymer used in the molecule contain over 50%, preferably at least 70% and more advantageously at least 80%, of the 1,4 configuration. Manufacturing methods for such materials IS are well known in the art and a number of suitable materials are commercially available (some of which are given in the examples above).

The 1,4-fraction of butadiene diols used in the present invention corresponds to the formula

20th

HO

CH2-CH = CH-CH2> - (CH-CH2) b

-OH

25th

where a can vary from 0.65 to 1.0, preferably from 0.75 to 0.85; b can vary from 0 to 0.35, preferably from 0.25 to 0.15; n can vary from 5 to 150, preferably 30 from 10 to 85; T is hydrogen or an organic radical derived from compounds such as styrene and its simpler derivatives, lower alkyl-acrylic acid esters and methacrylic acid esters and acrylonitriles, the latter being particularly advantageous. Of course, T should be chosen so that it does not cause any significant degradation in the properties given by the rest of the molecule. If b is different from O, the weight percentage of the comonomer residue belonging to b should expediently be less than 40% of the total copolymer part, preferably less than 30%.

The flexible polybutadienes or copolybutadienes which have functional groups with active hydrogen are reacted with the polyisocyanate in such a ratio that the polyisocyanate is present in a molar excess in relation to the concentration of the active hydrogen-containing groups in the polybutadiene. This ensures that a product results that has an -NCO group at each end of the polybutadiene segment. The molar excess of polyisocyanate can vary from 0.05 to 6.

The reaction can be carried out at temperatures from room temperature to 150 ° C., preferably from 40 ° C. to 120 ° C. After the flexible diol is added, it takes 0.1 to 30 hours to complete at the preferred temperature. If desired, the reaction can also be improved or accelerated by catalysts, and non-reactive solutions can also be used for viscosity control. The product of the above reaction is reacted with a Moläqui-60 valent, or preferably with a molar excess, based on the -NCO group content, of an acrylic or methacrylic ester having a hydroxyl or non-tertiary amine group in the molecule. This leads to an adhesive and sealing Prepo-65 polymer, which is sealed at both ends with functional acrylate or methacrylate groups. Suitable esters for use in the present invention conform to the formula

5

643577

R "0

I II

H2C = C-C-0-R "'- X-H,

in which X has the meaning already defined above, R "is hydrogen, chlorine, methyl or ethyl and R '" is a divalent lower alkylene radical having 1-8 carbon atoms, the phenylene or the naphthylene radical. Suitable hydroxyl and amino group-containing esters are, for example, acrylic acid hydroxyethyl ester, methacrylic acid hydroxyethyl ester, methacrylic acid amino ester, methacrylic acid 3-hydroxypropyl ester, methacrylic acid aminopropyl ester, acrylic acid hydroxyethyl methacrylate, methyl acrylate, methyl acrylate, methyl acrylate, methyl acrylate, methyl acrylate Bisphenol-A, all hydrogenated derivatives of bisphenol-A and cyclohexyldiol and similar compounds, but the suitable hydroxyl and amino group-containing esters are not limited to the compounds listed above. The reaction can be carried out in the presence of diluents or without them. Hydrocarbon is preferably used as the diluent, e.g. aliphatic, cycloaliphatic and aromatic hydrocarbons, for example benzene, toluene, cyclohexane, hexane, heptane and the like. However, other diluents, such as methyl isobutyl ketone, diamyl ketone, isobutyl methacrylic acid and cyclohexyl methacrylic acid, can also be used with advantage, if desired, especially where full compatibility with the sealant system is desired.

The temperature used in the reaction can also vary within a wide range. If the components are used in approximately chemically equivalent amounts, the appropriate temperatures may be about room temperature or below, e.g. Vary from 10 ° C to 15 ° C, up to temperatures from 100 ° C to 180 ° C. When the simpler isocyanate compounds are reacted, the ingredients are preferably reacted at or near room temperature, e.g. in a temperature range from 20 ° C to 30 ° C. At lower reaction temperatures, the use of a catalyst is recommended. When higher molecular weight isocyanate compounds are reacted, higher temperatures are more advantageous, e.g. from 40 ° C to 150 ° C.

The finished monomeric prepolymers produced according to the invention correspond to the formula

R "0

CH: = C-C-0-R '"* I * Dd * Ii *

wherein R "and R '" have the meanings given above, I is a polyisocyanate radical, D is an aromatic or cycloaliphatic polyol or polyamine radical, advantageously a diol and preferably a diol of a cycloaliphatic compound and Z is a polymeric or copolymeric butadiene diol or butadiene diamine radical, one has an average degree of polymerization of 5 to 150 monomer units per molecule and in which at least 50%, in particular 70%, of the butadiene units have the 1.4 configuration, and in which there is an integer which corresponds to the valence of Z, either 1 or Is 0, i is 0 when d = 0, and is otherwise a number equal to or less than the number of reactive hydrogen atoms of D. An asterisk (*) in the above formula denotes a urethane - (- NH- COO-) or ureide - (- NH-CO-NH -) - bond.

The prepolymers described above cure to a hard, tough resin under the influence of free radicals of a 5 peroxy initiator from the wide field of these known initiators. Examples of such initiators are the diacyl peroxides, e.g. Benzoyl peroxide, the dialkyl peroxides, e.g. Di-tertiary butyl peroxides, ketone peroxides such as e.g. Methyl ethyl ketone peroxides and easily hydrolyzing peresters, such as e.g. tert-butyl peracetate, tert-butyl perbenzoate, di-tert-butyl diperphthalate, etc. A particularly suitable class of peroxy initiators are the organic hydroperoxides, e.g. Cumoehydroperoxide, methyl ethyl ketone hydroperoxide, tert-butyl hydroperoxide, etc. Of these, cumoehydrope i5 oxide is particularly advantageous. The initiators should expediently be added in a concentration of 0.01% to 10% by weight of the entire adhesive or sealant mixture, preferably in a concentration of 0.1% to 5% by weight. . Another suitable class of initiators includes the compounds containing carbonyl groups which form free radicals by ultraviolet radiation, such as e.g. Acetophenone, benzophenone and the benzoin ethers. Suitable UV initiators are described in US patent application serial no. 356.679 from 2.5.1973 25. Mixtures of different initiators can also be used.

It is clear that the curable mixtures of the present invention are also suitable for a two-part adhesive or; Sealants can be used. In this case, the initiator or one of a combination of initiators can form the second component, which is only combined with the mixture at the point of use. For example, the one component can be applied to one of two surfaces to be connected and the initiator as the second component to the other of the two surfaces and the two surfaces can then be brought together. Likewise, one of the accelerators mentioned below can be applied separately as a second component to one of the two surfaces to be connected to one another.

If desired, the curing polymerization can be carried out by applying moderate heat, e.g. at 50 ° C to 150 ° C, are accelerated. At temperatures above 125 ° C, curing is usually completed in about 10 minutes or 45 less. The prepolymers produced according to the invention can be processed into anaerobic adhesives or sealants which harden at room temperature. Compositions of this type are well known in the art, including for example, from U.S. Patent No. 5,043,820 to Krieble and the aforementioned U.S. Patent 3,678,014; for such mixtures e.g. Hydroperoxide initiators are used, such anaerobic mixtures advantageously also polymerization accelerators, such as contain organic imides (e.g. benzoic acid sul-55 fimide) and primary, secondary or tertiary amines, as well as inhibitors or stabilizers from the group of quinones or hydroquinones. The accelerators are generally used in concentrations of less than 10% by weight, and the inhibitors in concentrations of 0.001% by weight to 0.1% by weight. In the form of an anaerobically curing adhesive or sealant mixture, there is the advantage of long-term stability and the ability to cure at room temperature in the absence of oxygen, e.g. between the threads 65 of screw and nut or between the opposite surfaces of the bearing and shaft. The anaerobic curing can be done by moderate heat, e.g. at temperatures up to 150 ° C.

643577

If desired, the adhesive or sealant mixtures can be prepared using diluents which are reactive during subsequent curing and are capable of copolymerizing with the prepolymers in question. Typical such diluents are the hydroxyalkyl alkyl esters, e.g. Acrylic acid hydroxyethyl ester, acrylic acid hydroxypropyl ester and the corresponding methacrylic acid ester, including methacrylic acid recyclohexyl ester and methacrylic acid tetrahydrofurfuryl ester. Other unsaturated reactive diluents such as e.g. Styrene and acrylonitrile can also be used. When using such diluents, their concentration should be less than 60% by weight and preferably in the range between 40 and 10% by weight.

One of the characteristic advantages of the prepolymers produced according to the invention is their unique ability to cure up to about 2.3 mm gap width within wide gaps. This behavior can be improved by moderate warming. However, it is preferred to use one of the "primers" known for anaerobic systems, e.g. that described in Toback U.S. Patent 3,625,930, and in particular that of thiourea compounds described in U.S. Patent Application 323,689 dated January 15, 1973. Such “primers” are advantageously applied as a spray, dissolved in a diluent solution, to one or both surfaces to be joined.

The following examples are specific embodiments of various aspects of the present invention, but the invention is not limited to these.

example 1

A nitrogen-cleaned four-necked resin kettle equipped with a stainless steel agitator, a nitrogen inlet tube, a thermometer, a condenser and an inlet connector is used to add 34.8 grams of toluene diisocyanate (TDI) (80% 2.4- / 20% 2,6-) supplied. The TDI is heated to 95-100 ° C. 18 grams of hydrogenated bisphenol-A (HBPA) are slowly added in 1 to 1.5 hours. 15 minutes after completion of the HBPA addition, a solution of 36.5 grams of dimethacrylic acid retriethylene glycol ester (TRIEGMA) and 150 ppm of a quinone stabilizer is added. 15 minutes later, 6.0 grams of HBPA are added in 3-5 servings. 15 minutes after all of the HPBA (24 grams total) has been added, the bath temperature is reduced so that the reaction mixture is at a temperature of 60-65 ° C. The reaction mixture consists of a toluene diisocyanate-capped HBPA prepolymer (abbreviated TDI * HBPA * TDI), dissolved in TRIEGMA. (In the present examples, asterisks represent urethane bonds).

To the reaction solution are added 98.0 grams of a degassed poly (butadiene-acrylonitrile) (P (BD-CN)) polyol resin, the butadiene portion of which contains approximately 80% of the 1,4 configuration (Arco CN-15 resin, OH = 0.62; manufactured by Arco Chemical Co., Philadelphia, Pennsylvania) within 2 hours. The reaction solution is kept at a temperature of approximately 65 ° C. Heating and stirring are then continued for an additional hour. Then a diluent of 24.5 grams of TRIEGMA and 150 ppm of a quinone stabilizer is gradually added to maintain a flowing reaction medium. Then 32 grams of 96% methacrylic acid hydroxypropyl ester (HPMA) are added and the reaction solution is kept at a temperature of 60-70 ° C. for a further 30 to 45 minutes. The resulting solution contains approximately 70% urethane

Dimethacrylic acid ester structures according to the general formula (HPMA * TDI * HBPA * TDI> * (P (BD-CN)).

Example 2

Example 1 was repeated with the modification that dimethacrylic acid 1,3-butylene glycol ester (BDMA) was used instead of TRIEGMA. The corresponding prepolymer was obtained.

Example 3

Example 1 was repeated with the modification that ethoxylated bisphenol A ester of dimethacrylic acid was used instead of TRIEGMA, using approximately 10% more to maintain a liquid medium. The corresponding prepolymer was obtained.

Example 4

Example 1 was repeated with the modification that bisphenol-A (BPA) was used instead of the hydrogenated bisphenol-A. The corresponding prepolymer was obtained.

Example 5

A nitrogen purged resin kettle heated to about 60 ° C, equipped as mentioned in Example 1 above, is charged with 21.5 grams of methylene bisphenyl isocyanate (MDI) and a solution of 21.5 grams of TRIEGMA and 150 ppm of a quinone stabilizer. When the solution has heated to 60-65 ° C, 93.0 grams of the degassed copolymeric butadiene acrylonitrile diol of Example 1 are gradually added over a 2 to 3 hour period. A diluent solution consisting of 23.8 grams of TRIEGMA and 150 ppm of a quinone stabilizer is used to maintain a liquid reaction medium. Finally, 25.6 grams of HPMA are added to obtain the desired urethane methacrylic ester end groups as described in Example 1. The prepolymer thus prepared corresponds to the following general formula

(HPMA * MDI) 2 * (P (BD-CN))

Example 6

The resin kettle described above is heated to about 65 ° C under a nitrogen atmosphere. Then 14 grams of TDI and a solution of 21.5 grams of TRIEGMA and 150 ppm of a quinone stabilizer are added to the kettle. Then, 130 grams of the degassed CH-15 described above is gradually added over a period of 2.5 to 3 hours, keeping the temperature at 65-70 ° C. After a further heating period of 1.5 to 2 hours and a periodic addition of a diluent solution (26.3 grams of TRIEGMA and 100 ppm of stabilizer), 20.3 grams of 96% HPMA are slowly added (within about 5 minutes). The solution is then heated for an additional hour to complete the reaction. The prepolymer obtained corresponds to the general formula

(HPMA * TDI) 2 * (P (BD-CN))

Example 7

The resin kettle described above is heated to about 60 ° C under a nitrogen atmosphere, the following being fed to the kettle: 24.4 grams of MDI and a solution of 20 grams of TRIEGMA and 200 ppm of one

6

5

10th

15

20th

25th

30th

35

40

45

50

55

60

65

Quinone stabilizer. When the solution has reached a temperature of 61-65 ° C, 130 grams of a degassed polybutadiene diol (P (BD)) (Arco Chemical Co., Philadelphia, Pennsylvania, R-45M, 80% 1.4 microstructure) are added and gradually over a period of 3 hours. In the final phase of this diol feed, a diluent solution (20.2 grams of TRIEGMA with 100 ppm of a quinone stabilizer) is added to maintain a liquid reaction medium. After the delivery of the diol and diluent solution is complete, 24.4 grams of 96% HPMA are added over a period of approximately 5 minutes. The heating is then continued for 1 to 2 hours. The resulting prepolymer corresponds to the general formula

(HPMA * MDI) 2 * (P (BD))

Example 8

This example describes a typical anaerobic adhesive mixture using one of the prepolymers described above or a mixture of several such prepolymers. With thorough stirring, 4.6 grams of methacrylic acid hydroxypropyl ester are added to 79 grams of the prepolymer resin product solution (70-75% solids). A solution of 0.7 grams of saccharin, dissolved in 7.6 grams of dimethacrylic acid triethylene glycol ester (as a solvent), is then stirred in. Then 5.6 grams of acrylic acid (adhesion improver) and 2.8 grams of cumoehydroperoxide (CHP) are added and stirring is continued for about an hour. Small amounts of stabilizers, curing accelerators, thickeners, plasticizers and the like can be added if desired, as is well known.

Example 9

Anaerobic adhesive mixtures were prepared in accordance with Example 8, using prepolymers which have been prepared in accordance with the preceding examples and are designated as follows

Plate I

General prepolymer structure

A

(HPMA * MDI) 2 * [P (BD)]

B

(HPMA * TDI * HBPA * TDI) 2 * [P (BD)]

C.

(HPMA * MDI) 2 * [P (BD-CN)]

D

(HPMA * TDI * HBPA * TDI) 2 * [P (BD-CN)]

E

(HPMA * TDI * BPA * TDI) 2 * [P (BD-CN)]

F

(HEMA * TDI * HBPA * TDI) 2 * [P (BD-CN)]

G

(HPMA * TDI) 2 * [P (BD-CN)]

The typical strength properties of these adhesive mixtures are given in Table II. The tensile strength measurements were carried out in accordance with ASTM D-2095-72.

Simply described in this test, the adhesion of two steel rods, which are connected at their ends by the adhesive, is checked. The opposite ends of the steel bars are then measured using a measuring device such as an "Instron tester" pulled apart and measured the tensile strength of the connection. The shear strength test was performed according to ASTM D-1002-65. In this test, the adhesion of two overlapping surfaces is checked by two steel test strips.

643577

The ends of the test piece assembled in this way are measured with a measuring device such as pulled apart by an "Instron tester" and the shear strength of the connection is measured. The shear strength is tested according to the military test regulations MIL-R-46082A (MR). The ability of an adhesive connection to hold a bushing or a bearing on a shaft is measured. The test checks the adhesion of a cylindrical pin within the bore of a suitable sleeve. The force required to press the pin out of the sleeve is then e.g. measured with an "Instron tester" or an appropriate measuring device. The shock resistance is tested in accordance with ASTM D-950-72. In this test, a steel block glued together with another steel block is pushed with a swinging pendulum. A suitable device is, for example, the “Baldwin Impact Tester”. The impact force required to separate the blocks is measured. The heat resistance test corresponds to the shear stress test described above, but the test specimen is previously heated to approx. 200 ° C for 1.25-1.5 hours and is also tested at this temperature. Heating (to about 93 ° C) was also used to accelerate curing in all tests, one hour in the tensile and shear stress and shear strength tests, and 1.5 hours in the impact test.

Tcifel II

Prepoly

Tensile

Shear sp.

Thrust

Push

Heat mere solid.

festig.

festig.

festig.

festig.

kp / cm2

kp / cm2

kp / cm:

kgm / cm2

kp / cm2

A

212.7

168.7

147.7

0.084

68.9

B

218.7

184.2

0.058

33.7

c

242.6

218

205.3

0.195

61.9

D

463.3

271.4

262.3

0.259

49.9

D (1)

483.7

310.8

312.2

0.304

63.3

E

275.6

246.1

0.264

63.3

F

288.3

• 232.7

0.156

49.9

G

251.3

146.9

180.0

0.257

(1) The prepolymer D (l) is prepared with ethoxylated bisphenol-A-dimethacrylic acid ester as a solvent instead of TRIEGMA.

It is also an advantageous feature of the present prepolymer adhesives that they are able to set to structurally acceptable strengths at room temperature without the use of a "primer" or activator. In the shear stress test, for example, the above-mentioned prepolymers D and F develop strengths of approximately 126.6 kp / cm 2 after 24 hours and 175.8-211 kp / cm 2 after 72 hours.

Example 10

One of the particular advantages of adhesives with mixtures made in accordance with the present invention is their ability to maintain sufficient strength values even when they are exposed to higher temperatures for an extended period of time. This is shown in Table III. The strength test used for this was the test of shear strength already described above. The test specimens are exposed to a temperature of approx. 230 ° C for the specified number of weeks and then divided into two groups, one of which was tested at room temperature and the other at a temperature of approx. 200 ° C. The resin used was the above prepolymer D.

7

5

10th

15

20th

25th

30th

35

40

45

50

55

60

65

643577

8th

Plate III

Shear stress resistance in kp / cm2 heat treatment time at room temperature at 200 ° C

Weeks

0

193.4

33.7

1.0

215.1

77.3

1.5

165.9

52.7

2.0

103.4

24.6

2.5

98.4

18.3

3.0

18.3

16.9

4.0

24.6

14.1

5.0

7.0

5.6

6.0

2.1

3.5

Example 11

Another clear advantage of the present prepolymers is their ability to be used in wide gaps e.g. Cure 1 mm and more. Table IV shows typical shear stress and shock resistance values for the above-mentioned prepolymers D at different gap widths. With the exception of the example specifically indicated in the table, curing was carried out at room temperature on sandblasted steel surfaces which had been provided with a known tetramethyl-thiourea activator as a "primer" before the prepolymers were applied. The curing time was up to 0.5 mm gap width 24 hours, and with gap widths of 1 mm and more 72 hours.

Plate IV

Gap width in mm

Shear strength in kp / cm2

Shock resistance in kgm / cm2

0

164.5

0.257

20th

126.6

0.193

41

100.5

0.212

55

67.5

0.118

85

25.3

85 *

96.3

♦ with additional heat setting over an hour at approx. 93 ° C.

Example 12

Using the prepolymers D (shown in Table I), a curable mixture was prepared by the method given in Example 8, but with the difference that 3-5% by weight (based on the total weight of the mixture) instead of the CHP ) Benzophenone were used. A 50-125 µm film of the mixture was applied to a piece of glass and exposed to ultraviolet radiation. The UV source was a 400 watt mercury io vapor lamp, which was installed in a “Porta-Cure 400” lamp. Both the lamp and the lamp were from the "American Ultraviolet Co." produced. The UV source was set to deliver 600 microwatts of radiation intensity to the film. After an irradiation time of 15 15-19 minutes, the mixture had solidified into a hard, dry film. The same mixture was used to connect the specimens for a shear strength test, but using glass strips instead of steel strips. The test specimens were exposed to UV radiation of 6000 microwatts at their 20 connection points. After about 40 seconds, the glass strips were so firmly connected that they could no longer be moved relative to one another by hand.

25th

Example 13

Using prepolymers D (shown in Table I), an adhesive mixture was prepared according to the method given in Example 8 above, but with the modification that 3-5% by weight (based on the total weight of the adhesive) instead of the CHP Mixture) benzoyl peroxide was used. A 50-125 µm film of the mixture was applied to a piece of steel and then held in an oven at about 93 ° C for 1.5 hours and then cooled to room temperature. The mixture of adhesives solidified into a dry, stable film.

A shear strength test was carried out using this adhesive mixture in accordance with the ASTM method mentioned in Example 9. The same thermal curing as mentioned above was used and the bond strength was found to be 263.7 kgf / cm 2.

B

Claims (27)

643577 2nd PATENT CLAIMS 1. Process for the preparation of curable adhesives or sealants, which is a curable reaction product with ester groups of the formula R " I. CH2 = C-COO-, where R "represents a hydrogen or chlorine atom or a methyl or ethyl group, contained in a mixture with at least one further component, characterized in that the preparation of the aforementioned curable reaction product (a) Organic, at least one ring-containing polyisocyanate initially with (b) a butadiene polymer or copolymer substituted by a plurality of hydroxyl or non-tertiary amine groups, which has an average degree of polymerization of 5 to 150 monomer units per molecule and in which at least 50% of the butadiene units have the 1,4 configuration, in a quantity ratio such that one mole of hydroxyl groups or one mole of non-tertiary amine groups of the substituted butadiene polymer or copolymer capable of reacting with isocyanate groups of the organic polyisocyanate account for more than one mole of isocyanate groups of the organic polyisocyanate, and thereafter with (c) a hydroxyl group or a non-tertiary amine group in the molecule of ester of unsubstituted or in the a-position to the carboxyl group substituted by a chlorine atom or a methyl or ethyl group acrylic acid in the ratio of at least one mole of ester to an isocyanate equivalent of the adduct of (a) and (b) implemented. 2. The method according to claim 1, characterized in that a poly (butadiene acrylonitrile) diol is used as the substituted butadiene copolymer (b). 3. The method according to claim 1, characterized in that as the polyisocyanate (a) the reaction product (ai) from aromatic or cycloaliphatic polyol or from a plurality of non-tertiary amine groups containing aromatic or cycloaliphatic polyamine and such an amount of aromatic or cycloaliphatic polyisocyanate that more than one mole of isocyanate groups of the polyisocyanate is used for one mole of hydroxyl groups of the polyol or for one mole of non-tertiary amine groups of the polyamine. 4. The method according to claim 1, characterized in that the polyisocyanate (a) is tolylene diisocyanate or a reaction product (a-i) of the type defined in claim 3, for the preparation of which toluene diisocyanate was used as the polyisocyanate. 5. The method according to claim 1, characterized in that the polyisocyanate (a) diphenylmethane-4,4'-diiso-cyanate or a reaction product (ai) of the type defined in claim 3, for its preparation as polyisocyanate diphenylmethane-4,4 'diisocyanate was used. 6. The method according to claim 3, characterized in that the reaction product (a-i) is a reaction product of hydrogenated bisphenol-A and tolylene diisocyanate. 7. The method according to claim 1, characterized in that one uses as the ester (c) methacrylate or ethyl methacrylate. 8. The method according to claim 1, characterized in that you make adhesives or sealants that contain an organic solvent. 9. The method according to any one of claims 1 to 8, characterized in that one manufactures adhesives or sealants which contain a solvent which is co-reactive during subsequent hardening. 10. The method according to any one of claims 1 to 9, characterized in that one manufactures adhesives or sealants which contain at least one free radical-forming polymerization initiator. 11. The method according to any one of claims 1 to 10, characterized in that adhesive or sealant is prepared which contain additives for anaerobic curing. 12. The method according to claim 10 or 11, characterized in that adhesive or sealant is prepared which contain a peroxy initiator as a free radical-forming polymerization initiator or as an additive for anaerobic curing. 13. The method according to claim 12, characterized in that the peroxy initiator is a hydroperoxide. 14. The method according to claim 13, characterized in that the hydroperoxide is cumene hydroperoxide. 15. The method according to claim 10, characterized in that adhesives or sealants are prepared which contain an initiator which can be activated by ultraviolet rays as the free radical-forming polymerization initiator. 16. The method according to any one of claims 11 to 14, characterized in that one manufactures adhesives or sealants which contain a polymerization accelerator. 17. The method according to claim 16, characterized in that an imide or an amine is used as the accelerator. 18. Curable adhesive or sealant, produced by the method according to claim 1. 19. Curable adhesive or sealant according to claim 18, produced by the method according to one of claims 2 to 9. 20. Curable adhesive or sealant according to claim 18, produced by the method according to one of claims 10 to 14. 21. A curable adhesive or sealant according to claim 18, produced by the method according to claim 15. 22. A curable adhesive or sealant according to claim 18, produced by the method according to claim 16 or 17. 23. Use of a curable adhesive or sealant according to claim 18 for bonding surfaces or sealing gaps between surfaces, characterized in that the adhesive or sealant is cured between said surfaces with the help of at least one free radical-forming polymerization initiator. 24. Use according to claim 23 of a curable adhesive or sealant according to one of claims 19 to 21. 25. Use according to claim 23 of a curable adhesive or sealant according to claim 22. 26. Use according to any one of claims 23 to 25, characterized in that the adhesive or sealant is applied to one of the surfaces to be treated and the or a free radical-forming polymerization initiator on the other surface, the two occupied surfaces are brought together and that Allow the mixture to harden. 27. Use according to claim 25, characterized in that one has to treat a polymerization accelerator on one and possibly also the other one 10th 15 20th 25th 30th 35 40 45 50 55 60 65 Applying the surfaces and the adhesive or sealant to the other of the surfaces to be treated, bringing the two occupied surfaces together and allowing the mixture to harden.