LIQUID MIXTURES OF PROPOXYLATED PARA-TOLUIDINES

Abstract

The invention relates to mixtures of propoxylated 4-toluidines containing two or more different di- or tri-propoxy lated or higher propoxylated p-toluidines in specific weight ratios, to methods for preparing them and to their use as polymerization accelerators or vulcanization accelerators or as hardener components in epoxy resins.

Claims

1. A mixture comprising two or more different compounds of the general formula (I) ##STR00002## in which R.sup.1 is hydrogen or methyl, but where the R.sup.1 radicals on directly adjacent carbon atoms do not both represent hydrogen and do not both represent methyl, and m and n represent integers, wherein 4-toluidine is present in a proportion of not more than 2% by weight, based on the total mass of all compounds of the formula (I) in the mixture, and the compounds of the formula (I) in which the sum total of m and n is the integer 2 are present in the mixture in a proportion of not more than 20% by weight, based on the total mass of all compounds of the formula (I), and the compounds of the formula (I) in which the sum total of m and n is at least the integer 6 are present in the mixture in a proportion of not more than 40% by weight, based on the total mass of all compounds of the formula (I).

2. The mixture as claimed in claim 1, wherein the compounds of the formula (I) in which the sum total of m and n is the integer 3 are present in the mixture in a proportion of 7% to 49% by weight, based on the total mass of all compounds of the formula (I).

3. The mixture as claimed in claim 1, wherein the compound of the formula (I) in which the sum total of m and n is the integer 4 is present in the mixture in a proportion of 10% to 49% by weight, based on the total mass of all compounds of the formula (I).

4. The mixture as claimed in claim 1, wherein every homologous group of compounds of the formula (I) is present in the mixture in a proportion of less than 50 percent by weight based on the total mass of all compounds of the formula (I) in the mixture.

5. The mixture as claimed in claim 1, wherein the mixture contains a proportion of 4-toluidine of less than 0.1% by weight based on the total mass of all compounds of the formula (I) in the mixture.

6. The mixture as claimed in claim 1, wherein the mixture is in a liquid state of matter at temperatures of 5 to 40° C.

7. The mixture as claimed in claim 1, wherein the mixture has a dynamic viscosity of 500 to 20 000 mPas at a temperature of 25° C., measured to DIN 53019 with a rotary viscometer.

8. The mixture as claimed in claim 1, wherein the mixture contains 96% to 100% by weight of compounds of the formula (I).

9. A process for preparing the mixture as claimed in claim 1, comprising the reacting the compounds of the formula (I) in which R.sup.1 is hydrogen or methyl, but where the R.sup.1 radicals on directly adjacent carbon atoms do not both represent hydrogen and do not both represent methyl, and in which m and n are the integer 1, with from 1.0 to 4.0 mol of propylene oxide per mole of 4-toluidine used in the presence of a catalyst.

10. The process for preparing the mixtures as claimed in claim 9, wherein the reacting step is effected at temperatures of 80 to 150° C.

11. The process for preparing the mixtures as claimed in claim 9, wherein the reacting step is effected in the presence of 0.01 to 0.05 mol of catalyst selected from the group consisting or alkali metal and alkaline earth metal hydroxides, alkali metals, lithium alkyls, sodium hydride, complex hydrides, lithium aluminum hydride, sodium bis(methoxyethoxy)aluminum dihydride, or alkali metal alkoxides, per mole of compound of the formula (I) used in which R.sup.1 is hydrogen or methyl, but where the R.sup.1 radicals on directly adjacent carbon atoms do not both represent hydrogen and do not both represent methyl, and in which m and n are the integer 1 (N,N-dipropoxy-p-toluidine).

12. The process for preparing the mixtures as claimed in claim 9, comprising the preparation of the compound of the formula (I) in which R.sup.1 is hydrogen or methyl, but where the R.sup.1 radicals on directly adjacent carbon atoms do not both represent hydrogen and do not both represent methyl, and in which m and n are the integer 1 (N,N-dipropoxy-p-toluidine), by reaction of 4-toluidine with from 1.8 to 2.2 mol of propylene oxide per mole of 4-toluidine used, at temperatures of 80 to 150° C. in the absence of catalysts.

13. The process for preparing the mixtures as claimed in claim 9, wherein the reacting step takes place in the absence of solvents.

14. The process for preparing the mixtures as claimed in claim 9, wherein the 4-toluidine has a proportion of not more than 0.2% by weight of 3-toluidine, based on 4-toluidine.

15. The use of the mixtures as claimed in claim 1 as polymerization or vulcanization accelerators, or as hardener component for epoxy resins.

16. A polymeric product obtainable by polymerization, of a polyester in the presence of the mixture as claimed in claim 1 as polymerization or vulcanization accelerator or as hardener component for epoxy resins.

Description

EXAMPLES

Examples 1a to 1e: Production of Propoxylated Toluidine Proceeding from N,N-dipropoxy-p-toluidine

Example 1a

[0062] A 3 liter autoclave (stainless steel) with stirrer, internal thermometer, immersed introduction tube for the propylene oxide and riser tube for removal was initially charged with 1425 g of 98% N,N-dipropoxy-p-toluidine [compound of the formula (I) in which m and n are each the integer 1; 6.25 mol] in molten form and 10.9 g of about 90% potassium hydroxide flakes (0.175 mol). The autoclave was closed, inertized by injecting nitrogen, decompressed and evacuated to about 670 hectopascal (hPa) (absolute pressure). The contents were heated to >80° C. in order to largely melt the N,N-dipropoxy-p-toluidine. Then the melt was heated up to the desired reaction temperature (120° C.). At this temperature, the envisaged amount of propylene oxide (here 690.1 g=11.88 mol, corresponding to 1.9 molar equivalents based on N,N-dipropoxy-p-toluidine, i.e. a total of 3.9 molar equivalents based on 4-toluene) was metered in at a rate of about 163 g/h, with achievement of a pressure of 0.18 MPa (absolute pressure) for a short time. This pressure was typically not exceeded in the other examples either. About 90 min after the metered addition had ended, the total pressure had dropped to a pressure of about 800 hPa that was then constant for about 15 min. This was followed by stirring at reaction temperature for a further 60 min, then cooling to 40° C., compensating for the reduced pressure with nitrogen, blowing out any propylene oxide still present with nitrogen, and dispensing of the mixture through a clarifying filter. 2109.3 g (yield: 99.200 of the use amounts) of product was obtained, which has the following distribution (in percent by weight) of the homologs of the formula (I):

TABLE-US-00001 m = 1; m = 1; n = 1 n = 2 m + n = 4 m + n = 5 m + n > 5 Content of 0.51% by 41.7% by 35.6% by 14.6% by 6.27% by compound of weight weight weight weight weight the formula (I)
Examples 1b to 1e were conducted analogously—if appropriate in a 0.5 liter autoclave. Rather than the amounts envisaged in example 1a, examples 1b to 1e were conducted with the data specified in table 1.

TABLE-US-00002 TABLE 1 Reaction data of examples 1b to 1e Example 1b Example 1c Example 1d Example 1e Reaction data inventive inventive inventive noninventive Autoclave size 3 L 3 L 0.5 L 0.5 L 98% N,N- 1425 g 1425 g 226 g 226 g dipropoxy-p- 6.25 mol 6.25 mol 1.00 mol 1.00 mol toluidine Catalyst: 99.8% sodium 99.8% sodium 90% potassium 90% potassium hydroxide hydroxide hydroxide hydroxide beads beads flakes flakes Amount of 5.73 g 5.73 g 1.13 g 1.13 g catalyst 0.143 mol 0.143 mol 0.018 mol 0.018 mol 2.3 mol % .sup.1) 2.3 mol % .sup.1) 1.8 mol % .sup.1) 1.8 mol % .sup.1) Reaction 120° C. 120° C. 120° C. 120° C. temperature Propylene 671.9 g 635.6 g 58.2 g 29.1 g oxide 11.56 mol 10.94 mol 1.00 mol 0.50 mol 1.85 moleq..sup.2) 1.75 moleq..sup.2) 1.00 moleq..sup.2) 0.50 moleq..sup.2) Yield 2047 g 2012 g 278 g 250 g 97.4% of the 97.4% of the 97.4% of the 97.6% of the amounts used amounts used amounts used amounts used Content of compound of the formula (I) m = 1; n = 1 0.95% by 1.31% by 11.0% by 47.4% by weight weight weight weight m = 1; n = 2 44.6% by 47.9% by 72.2% by 41.9% by weight weight weight weight m + n = 4 32.0% by 31.0% by 13.0% by 10.5% by weight weight weight weight m + n = 5 14.0 12.4% by 3.65% by <0.1% by weight weight weight m + n > 5  7.66 6.20% by <0.1% by <0.1% by weight weight weight State of matter liquid, liquid, liquid, significantly at 20° C. slightly slightly viscous viscous, viscous viscous predominantly with solid fractions State of matter distinctly distinctly highly solid with at 5° C. viscous viscous viscous vitreously solidified fractions State of matter vitreously vitreously vitreously solid with at −15° C. solidified solidified solidified vitreously solidified fractions .sup.1) 1 mol %: 0.01 mol of base based on 1 mol of N,N-dipropoxy-p-toluidine used .sup.2)x moleq.: x mol of propylene oxide based on 1 mol of N,N-dipropoxy-p-toluidine used

Examples 2a to 2e: Production of Propoxylated Toluidine Proceeding from 4-toluidine

Example 2a

[0063] A 3 liter autoclave (stainless steel) with stirrer, internal thermometer, immersed introduction tube for the propylene oxide and riser tube for removal was initially charged with 672.1 g of 99.7% 4-toluidine (6.25 mol) in molten form. The autoclave was closed, inertized by injecting nitrogen, decompressed and evacuated to about 670 hPa (abs.). The contents were heated up to >45° C., without stirring at first, in order to fully melt the 4-toluidine. Then the melt was heated further up to the desired reaction temperature (120° C.). At that temperature, 726.4 g of propylene oxide (12.49 mol) was metered in at a rate of about 163 g/h in the absence of catalysts, with attainment of a maximum pressure of 0.27 MPa (abs.) for a short period of time. This pressure was typically not exceeded in the other examples either. About 3.5 h after the metered addition had ended, the total pressure had dropped to a pressure of about 770 hPa that was then constant for about 15 min. Stirring was then continued at reaction temperature for a further 60 min, then the mixture was cooled to 80 to 100° C., and the reduced pressure was compensated for with nitrogen. By means of sampling, it is possible to verify whether the typical composition of N,N-dipropoxy-p-toluidine has been attained.

[0064] Subsequently, the envisaged amount (2.8 mol % based on 4-toluidine used) of solid about 90% potassium hydroxide was added, and the autoclave was closed again, inertized as described above, evacuated and heated up to the desired reaction temperature of 120° C. Subsequently, a further 690.1 g (11.88 mol) of propylene oxide was metered in at about 163 g.h, with observation of a pressure rise toward the end by about 760 hPa to about 0.143 MPa (absolute). About 50 min after the metered addition had ended, the total pressure had dropped to the original pressure of 670 hPa. This was followed by stirring at reaction temperature for a further 60 min, then cooling to 40° C., compensating for the reduced pressure with nitrogen, blowing out any propylene oxide still present with nitrogen, and dispensing of the mixture through a clarifying filter. 2087.4 g (yield: 99.4% of the amounts used) of product was obtained, which contains the following distribution (in percent by weight) of the homologs of the formula (I):

TABLE-US-00003 m = 1; m = 1; n = 1 n = 2 m + n = 4 m + n = 5 m + n > 5 Content of 1.69% by 38.9% by 35.2% by 15.6% by 7.00% by compound of weight weight weight weight weight the formula (I)
Examples 2b to 2e were conducted analogously—if appropriate in a 0.5 liter autoclave. Rather than the amounts envisaged in example 2a, examples 2b to e were conducted with the data specified in table 2.

TABLE-US-00004 TABLE 2 Reaction data of examples 2b to 2e Example 2b Example 2c Example 2d Example 2e Reaction data inventive inventive inventive noninventive Autoclave size 0.5 L 0.5 L 0.5 L 0.5 L 99.7% 4- 107.5 g 107.5 g 107.5 g 77.4 g toluidine 1 mol 1 mol 1 mol 0.72 mol 1st stage Propylene 116.2 g 116.2 g 116.2 g 83.6 g oxide 2 mol 2 mol 2 mol 1.44 mol 2.0 moleq..sup.2) 2.0 moleq..sup.2) 2.0 moleq..sup.2) 2.0 moleq..sup.2) Reaction 110° C. 130° C. 120° C. 120° C. temperature 2nd stage Catalyst: 90% 90% 90% 90% potassium potassium potassium potassium hydroxide hydroxide hydroxide hydroxide flakes flakes flakes flakes Amount of 1.75 g 1.75 g 1.75 g 1.26 g catalyst 0.028 mol 0.028 mol 0.028 mol 0.020 mol 2.8 mol % .sup.1) 2.8 mol % .sup.1) 2.8 mol % .sup.1) 2.8 mol % .sup.1) Reaction 110° C. 130° C. 120° C. 120° C. temperature Propylene 101.6 g 101.6 g 58.1 g 177.8 g oxide 1.75 mol 1.75 mol 1.0 mol 3.06 mol 1.75 moleq..sup.2) 1.75 moleq..sup.2) 1.0 moleq..sup.2) 4.25 moleq..sup.2) Yield 317.5 g 317.9 g 266.3 g 316 g 97.1% of the 97.1% of the 93.9% of the 92.9% of the amounts used amounts used amounts used amounts used Content of compound of the formula (I) m = 1; n = 1 2.27% by 1.08% by 12.9% by 0.55% by weight weight weight weight m = 1; n = 2 47.8% by 33.5% by 74.9% by 5.36% by weight weight weight weight m + n = 4 32.7% by 35.3% by 8.71% by 16.0% by weight weight weight weight m + n = 5 11.3% by 18.2% by 0.39% by 20.8% by weight weight weight weight m + n > 5 3.79% by 10.2% by 0.20% by 56.3% by weight weight weight weight State of matter liquid, liquid, liquid, liquid, at 20° C. slightly slightly viscous slightly viscous viscous viscous State of matter distinctly distinctly highly distinctly at 5° C. viscous viscous viscous viscous State of matter vitreously vitreously vitreously vitreously at −15° C. solidified solidified solidified solidified .sup.1) mol %.: 0.01 mol of base based on 1 mol of 4-toluidine used .sup.2)x moleq.: x mol of propylene oxide based on 1 mol of 4-toluidine used