ASPHALT COMPOSITION COMPRISING MONOMERIC MDI AS THERMOSETTING REACTIVE COMPOUND

Abstract

An asphalt composition comprising 0.1 to 10.0 wt.-% monomeric MDI based on the total weight of the composition.

Claims

1.-16. (canceled)

17. An asphalt composition comprising 0.1 to 10.0 wt.-% monomeric MDI based on the total weight of the composition.

18. The asphalt composition according to claim 17, wherein the monomeric MDI is carbodiimide modified.

19. The asphalt composition according to claim 18, wherein the weight percentage of 4,4′-MDI in the carbodiimide modified monomeric MDI is in the range of from 65 to 85% and the weight percentage of carbodiimide is in the range of from 15 to 35% in the carbodiimide modified monomeric MDI.

20. The asphalt composition according to claim 17, wherein at least 18% by weight based on the total weight of the composition are particles with a sedimentation coefficient above 5000 Sved in a white spirit solvent.

21. The asphalt composition according to claim 17, wherein above 20% by weight based on the total weight of the composition are particles with a sedimentation coefficient in a range of from 10000 to 1000000 Sved in a white spirit solvent.

22. The asphalt composition according to claim 18, wherein the carbodiimide modified monomeric MDI has a functionality in the range of from 2.1 to 2.5

23. The asphalt composition according to claim 18, wherein the carbodiimide modified monomeric MDI has a viscosity in the range of from 20 to 100 mPa*s at 25° C.

24. The asphalt composition according to claim 18, wherein the amount of the carbodiimide modified monomeric MDI is of from 0.5 to 5.0 wt.-% based on the total weight of the composition.

25. The asphalt composition according to claim 18, wherein the amount of the carbodiimide modified monomeric MDI is of from 0.8 to 3.0 wt.-% based on the total weight of the composition.

26. The asphalt composition according to claim 18, wherein the carbodiimide modified monomeric MDI has iron content in the range of from 1 to 80 ppm.

27. A process for the preparation of an asphalt composition according to claim 17 comprising the following steps: a) heating up a starting asphalt to a temperature of from 110 to 190° C.; b) adding a desired amount of monomeric MDI or carbodiimide modified monomeric MDI under stirring to produce a reaction mixture; and c) stirring the reaction mixture after step b) at a temperature in the range of from 110 to 190° C. for at least 2.5 h wherein the stirring is carried out under an oxygen atmosphere.

28. A process according to claim 27, wherein the temperature of at least one of the heating and stirring steps is in the range of from 110 to 150° C.

29. A process according to claim 27, wherein the temperature in step a) and step c) are the same and in the range of from 110 to 150° C.

30. A process according to claim 27, wherein the temperature is in the range of from 110 to 150° C. and the reaction mixture is stirred for at least 4 h after the adding step b).

31. A process according to claim 27, wherein the end of the reaction is determined by IR spectroscopy.

32. A method comprising utilizing the asphalt composition according to claim 17 for the preparation of an asphalt mix composition.

Description

EXAMPLES AND COMPARATIVE EXAMPLES

General Procedure for the Preparation of an Asphalt Composition

[0075] 2.5 kg of asphalt in the respective grade according to table 1 was heated up to 140° C. under oxygen atmosphere and stirred at 400 rpm in an oil bath (temperature set up to 150° C.) When the internal temperature of 100° C. was reached, 50 g of the respective thermosetting reactive compound according to table 1 was added to the melted asphalt. The stirring energy varied from 5.6 to 12 W/l. The reaction is further processed at 140° C. for 420 minutes before being cooled down at room temperature. The samples were dispatched into cans for further testing and stored at room temperature.

[0076] For comparative examples 1 (#1), 4 (#4) and 6 (#6) 2.5 kg of asphalt with the respective grade according to table 1 was heated up to 140° C. under oxygen atmosphere and stirred at 400 rpm in an oil bath (temperature set up to 150° C.) for up to 420 minutes before being cooled down at room temperature. The samples were dispatched into cans for further testing and stored at room temperature.

[0077] For example 5 (#5) 3000 g of asphalt 64-22 was heated in an oven at 150° C. for 2 hours in a closed container. The preheated sample had a temperature of 150° C. when the cover was removed. Afterwards it was laced in a heating mantle under oxygen atmosphere. With 20% mixer speed the asphalt was heated further with an electric heating mantle using a temperature controller in the asphalt to hold the temperature at 150° C.±2° C. When the internal temperature of 150° C. was reached, 60 g of mMDI with a functionality of 2.2 (CDI13) was added to the melted asphalt. The reaction is further processed at 150° C. for 150 Minutes.

[0078] For comparative example 2 (#2) 2.5 kg of asphalt 50-70 was heated up to 140° C. under oxygen atmosphere and stirred at 400 rpm in an oil bath (temperature set up to 150° C.). When the internal temperature of 100° C. was reached, 50 g of the AS20 (2.0 wt.-%) was added to the melted asphalt. The reaction is further stirred at 140° C. for 420 minutes before being cooled down at room temperature. The sample was then used to determine the particle percentage of the asphalt composition using the analytical ultracentrifuge see results in table 2.

[0079] For example 3 (#3) 2.5 kg of asphalt 50-70 was heated up to 140° C. under oxygen atmosphere and stirred at 400 rpm in an oil bath (temperature set up to 150° C.). When the internal temperature of 100° C. was reached, 50 g of the mMDI CDI13 (2.0 wt.-%) was added to the melted asphalt. The reaction is further stirred at 140° C. for 420 minutes before being cooled down at room temperature. The sample was then used to determine the particle percentage of the asphalt composition using the analytical ultracentrifuge see results in table 2.

[0080] For example 7 (#7) 2.5 kg of asphalt 70-100 was heated up to 140° C. under oxygen atmosphere and stirred at 400 rpm in an oil bath (temperature set up to 150° C.). When the internal temperature of 100° C. was reached, 50 g of the mMDI CDI13 (2.0 wt.-%) was added to the melted asphalt. The reaction is further processed at 140° C. for 420 minutes before being cooled down at room temperature. The sample was then used to determine the particle percentage of the asphalt composition using the analytical ultracentrifuge see results in table 2.

Thermosetting Reactive Compound Used in the Examples

[0081] mMDI having a functionality of 2.2, a NCO content of 29.5% and a viscosity of 40 mPa*s at 25° C. named in the following CDI13 and pMDI having a functionality of 2.7, a NCO content of 31.5% and a viscosity of 210 mPa*s at 25° C. named in the following As20 were used.

[0082] mMDI and pMDI with respective functionality are commercially available for example at the following companies: Covestro, BASF SE, Huntsmann etc.

Methods for Detecting Physical Properties in an Asphalt or an Asphalt Composition or Asphalt Mix

The Values of the Examples are Detected According to the Respective DIN Regulation

Detailed Description of the Used Method:

Asphalt Tests

Softening Point DIN EN 1427

[0083] Two horizontal disks of bitumen, cast in shouldered brass rings, are heated at a controlled rate in a liquid bath while each supports a steel ball. The softening point is reported as the mean of the temperatures at which the two disks soften enough to allow each ball, enveloped in bitumen, to fall a distance of (25±0.4) [mm].

Rolling Thin Film Oven Test DIN EN 12607-1

[0084] Bitumen is heated in bottles in an oven for 85 [min] at 163 [° C.]. The bottles are rotated at 15 [rpm] and heated air is blown into each bottle at its lowest point of travel at 4000 [mL/min]. The effects of heat and air are determined from changes in physical test values as measured before and after the oven treatment.

Dynamic Shear Rheometer (DSR) DIN EN 14770—ASTM D7175

[0085] A dynamic shear rheometer test system consists of parallel plates, a means for controlling the temperature of the test specimen, a loading device, and a control and data acquisition system.

Multiple Stress Creep Recovery Test DIN EN 16659—ASTM D7405

[0086] This test method is used to determine the presence of elastic response in an asphalt binder under shear creep and recover at two stress level (0.1 and 3.2 [kPa]) and at a specified temperature (50 [° C.]). This test uses the DSR to load a 25 [mm] at a constant stress for 1 [s], and then allowed to recover for 9 [s]. Ten creep and recovery cycles are run at 0.100 [kPa] creep stress followed by ten cycles at 3.200 [kPa] creep stress.

Potentiometric Titration Method for Determining Reactive Groups in an Asphalt:

Acid Value

[0087] Approx. 0.5-1 g sample was dissolved in 50 ml toluene and titrated potentiometrically with 0.1 mol/l tetrabutylammonium hydroxide solution. A few drops of water can be added to the titration solution to ensure sufficient conductivity. A blank value was determined as well.

Base Value

[0088] Approx. 0.5-1 g sample was dissolved in 50 ml toluene and titrated potentiometrically with 0.1 mol/l trifluoromethane sulfonic acid solution. A few drops of water can be added to the titration solution to ensure sufficient conductivity. A blank value was determined as well.

Determination of the Particle Parts of the Asphalt Composition Using the Analytical Ultracentrifuge (AUC)

[0089] For the determination of the particle parts of the asphalt composition, fractionation experiments using analytical ultracentrifugation were conducted. Sedimentation velocity runs using a Beckman Optima XL-I (Beckman Instruments, Palo Alto, USA) were performed. The integrated scanning UV/VIS absorbance optical system was used. A wavelength of 350 nm was chosen. The samples have been measured at a concentration of about 0.2 g/L after dilution in a white spirit solvent (CAS-Nr.:64742-82-1). In order to detect the soluble and insoluble parts, the centrifugation speed was varied between 1000 rpm and 55,000 rpm.

[0090] The distribution of sedimentation coefficients, defined as the weight fraction of species with a sedimentation coefficient between s and s+ds, and the concentration of one sedimenting fraction were determined using a standard analysis Software (SEDFIT). The change of the whole radial concentration profile with time was recorded and converted in distributions of sedimentation coefficient g(s). The sedimentation coefficient is in units of Sved (1 Sved=10-13 seconds). The particle parts of the asphalt composition were determined by quantifying the light absorption of the fast and slow sedimenting fractions at the used wavelength.

TABLE-US-00001 TABLE 1 Results of samples 1 to 7, showing viscosity value before and after modification (without storage), MSCR after short term aging (RFTO) and phase angle values. Before storage MSCR (64° C.) aafter RFTO Soft. Visco 0.1 kPa 1.6 kPa 3.2 kPa Phase Angle Pt (Pas) Recovery Jnr Recovery Jnr Recovery Jnr (64° C., [°]) Samples (° C.) @ 135° C. (%) (kPa−1) (%) (kPa−1) (%) (kPa−1) After RFTO #1 Pen — 50 0.392 1.6 0.74  0.2 0.85  −1.2 0.935 — 50/70 #2 Pen 2% 65.2 1.079 34.6 0.121 32.7 0.136 28.0 0.151 71.6 50/70 AS 20 #3 Pen 2% 58 0.808 56.5 0.116 52.4 0.127 45.3 0.147 72.5 50/70 CDI13 #4 PG64- — — 0.383 5 2.569 — — 1 2.988 82.5 22 #5 PG64- 2% — 1.159 76 0.093 — — 49 0.203 66.3 22 CDI13 #6 Pen — 47.8 0.28 5.8 0.789 2.2 1.041 −0.5 1.239 — 70/100 #7 Pen 2% 66.6 0.95 58.0 0.067 55.7 0.076 50.7 0.081 65.7 70/100 CDI13

TABLE-US-00002 TABLE 2 Results of particle parts determination of asphalt composition of examples 3, and 7and comparative examples 1, 2, and 6 using the analytical ultracentrifuge, the concentration is particles in wt.-% based on the total weight of the respective composition. Component @ Component @ N = 50000 U/min N = 1500 U/min S50 Concentration S50 Concentration Samples [Sved] [wt.-%] [Sved] [wt.-%] #1 0.3 94 21000 6 #2 0.2 75 35000 25 #3 0.5 54 27513 46 #6 0.1 89 99500 11 #7 0.1 72 92500 28

TABLE-US-00003 TABLE 3 Storage stability/viscosity stability of comparative samples #1, #2 and sample 3 at high temperature (150° C.) Storage at 150° C. 3 days 5 days Samples Soft. Pt (° C.) Visco (Pas) Soft. Pt (° C.) Visco (Pas) #1 Pen — — — — 50/70 #2 Pen 67 2.021 87.8 7.317 50/70 #3 Pen 64.6 1.88 73.6 3.732 50/70