Asphalt modifier and composition containing the same

Abstract

To provide an asphalt modifier that can be operated at a relatively low temperature and makes it possible to improve water resistance or non-flowability of asphalt.SOLUTION: An asphalt modifier contains a compound of formula (1).SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to an asphalt modifier and a composition containing the same, and also to a method for improving the water resistance and / or non-fluidity of asphalt.

Background Art

[0002] Asphalt is widely used as a road paving material. Asphalt has a viscosity that decreases at high temperatures, improving workability, and quickly increases in viscosity and solidifies when the temperature drops after construction, enabling construction in a short time. It also has high weather resistance and corrosion resistance, making it suitable as a road paving material. On the other hand, in roads paved with asphalt, the viscosity of asphalt decreases due to the temperature rise in summer, resulting in rutting due to plastic deformation, or the adhesion between the aggregate with a hydrophilic surface and the hydrophobic asphalt is low, causing the asphalt to peel off from the aggregate. This particularly shortens the lifespan of the pavement on roads with high traffic volume. To address these issues, research has been conducted on mixing polymers (polymer modifiers) with asphalt to increase non-fluidity at high temperatures and improve adhesion to aggregates, and it is commercially available as modified asphalt. It is also known to blend an oil gelling agent with asphalt together with a polymer modifier (Patent Document 1), but mixing the oil gelling agent alone with asphalt is not well known. Non-Patent Document 1 describes that when mixing a dicarboxylic acid, which is an oil gelling agent, with asphalt, the temperature range in which the asphalt is solid increases, and the hardness and elastic modulus of the asphalt at room temperature also improve, but it does not describe other oil gelling agents, nor does it mention anything about the water resistance of asphalt.

[0003] Also, Patent Documents 2 and 3 and Non-Patent Document 2 describe that derivatives of 1,5-anhydroglucitol or glucopyranose are useful as oil gelling agents, but do not describe their blending with asphalt.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Non-Patent Document

[0005]

Non-Patent Document 1

Non-Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] In order to uniformly disperse a polymer modifier in asphalt to produce modified asphalt, it is necessary to continuously stir the asphalt and the polymer modifier at a high temperature around 200°C for 4 to 5 hours. However, in this process, there are problems such as thermal degradation of the asphalt and the polymer modifier, a large amount of CO2 emissions, and furthermore, workers are exposed to high temperatures at the construction site. In addition, when asphalt comes into contact with water, aggregates in the asphalt are damaged because the aggregates of polar components in the asphalt interact with water. Therefore, when outdoor asphalt is exposed to rain, peeling from the aggregates may occur, which can cause damage to road paving. In addition, roads paved with asphalt are prone to rutting and cracking due to temperature changes (especially in summer). Therefore, an object of the present invention is to provide an asphalt modifier that can be operated at a relatively low temperature and can improve the water resistance or non-fluidity of asphalt.

Means for Solving the Problems

[0007] As a result of intensive studies to solve the above problems, the present inventors have found that a specific oil gelling agent can be operated at a relatively low temperature and can improve the water resistance or non-fluidity of asphalt, and thus completed the present invention. That is, the present invention provides an asphalt modifier shown below, a composition containing the same, and a method for improving the water resistance and / or non-fluidity of asphalt. 〔1〕Formula (1):

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Advantages of the Invention

[0008] According to the present invention, by using the compound of formula (1), the production of the asphalt composition can be carried out at a relatively low temperature, and the water resistance and / or non-fluidity of the asphalt can be improved. Therefore, it is possible to improve the production environment of the asphalt or the durability of building materials using the asphalt.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0010] Hereinafter, the present invention will be described in more detail. The "asphalt modifier" described in this specification refers to an additive capable of improving the physical properties of asphalt. The asphalt modifier can be targeted at asphalt commonly used in the art without particular limitation. For example, the asphalt may be natural asphalt, petroleum asphalt, or a mixed asphalt thereof. The natural asphalt may be, for example, gilsonite, grahamite, or Trinidad Lake asphalt. The petroleum asphalt may be straight asphalt of various penetration grades obtained by distillation of crude oil, blown asphalt or semi-blown asphalt produced by blowing air into the straight asphalt in the presence or absence of a catalyst, or solvent-deasphalted asphalt produced when separating asphaltene from a fraction containing asphaltene with a solvent such as propane or n-butane.

[0011] The asphalt modifier of the present invention has the formula (1):

Chemical formula

[0012] Each R is independently an acyl group derived from a linear saturated fatty acid having 10 to 22 or 12 to 18 carbon atoms, or Each R is independently hydrogen, a linear alkyl group having 10 to 22 or 12 to 18 carbon atoms, an acyl group derived from a linear saturated fatty acid having 10 to 22 or 12 to 18 carbon atoms, and the following formula:

Chemical formula

[0013] The compound of formula (1) can be appropriately synthesized by using means commonly used in the art without particular limitation. For example, the compound of formula (1) can be appropriately synthesized with reference to the synthesis procedures described in Patent Document 2 and Non-Patent Document 2 (and further Patent Document 3 if necessary).

[0014] Since the compound of formula (1) has a lower melting point than conventionally used polymer modifiers, it can be used at a lower temperature compared to when using polymer modifiers. Also, without being bound by a specific theory, the compound of formula (1) can be uniformly dispersed in asphalt and can be connected in a fibrous or layered manner among the compounds, so it is considered that a network structure of the fibers can be formed in the asphalt, improving the water resistance or non-fluidity of the asphalt.

[0015] In one aspect, the compound is of formula (2) or (3):

Chemical formula

Chemical formula

[0016] In certain embodiments, in the compound, one or fewer of the Rs is hydrogen. Preferably, R is not hydrogen, that is, each R is independently an acyl group derived from a straight-chain saturated fatty acid having 10 to 22 carbon atoms, or each R is independently selected from the group consisting of a straight-chain alkyl group having 10 to 22 carbon atoms, an acyl group derived from a straight-chain saturated fatty acid having 10 to 22 carbon atoms, and an acyl group derived from the GABA derivative, and at least one of the Rs is an acyl group derived from the GABA derivative. In certain embodiments, all of the Rs are simultaneously an acyl group derived from the straight-chain saturated fatty acid or an acyl group derived from the GABA derivative. Compounds with less hydrogen as R have higher hydrophobicity and are more likely to crystallize, so the target compound can be easily isolated simply by crystallization and filtration, and the purification load is reduced.

[0017] The asphalt modifier of the present invention may further contain well-known raw materials blended with asphalt as long as the object of the present invention is not impaired. For example, the asphalt modifier may further contain additional asphalt modifiers such as polymer modifiers. The polymer modifier is not particularly limited, and examples thereof include natural rubber (NR), styrene-butadiene random copolymer (SBR), polychloroprene (CR), polybutadiene (BR), acrylonitrile-butadiene copolymer (NBR), ethylene-propylene copolymer (EPDM), polyethylene (PE), polypropylene (PP), ethylene-vinyl acetate copolymer (EVA), ethylene-ethyl acrylate copolymer (EEA), styrene-butadiene block copolymer (SBS), and / or styrene-isoprene block copolymer (SIS).

[0018] In another aspect, the present invention also relates to a composition (asphalt composition) comprising asphalt and the compound of formula (1). The content of the compound of formula (1) is not particularly limited, but for example, it may be about 0.005 to about 0.5 by mass ratio with respect to the content of the asphalt, and preferably about 0.03 to about 0.3. The composition of the present invention can be prepared by mixing asphalt and the compound of formula (1) at, for example, about 70°C to about 170°C, preferably about 80°C to about 160°C.

[0019] The asphalt composition of the present invention is less likely to change its surface structure even when it comes into contact with water after solidification, and has high water resistance. In addition, since the asphalt composition maintains high viscosity and is difficult to flow even in a high-temperature environment, it is difficult to separate from the aggregate when mixed with the aggregate. Therefore, the asphalt composition does not need to contain an additional asphalt modifier such as a polymer modifier. Note that there is no hindrance to the asphalt composition further containing an additional asphalt modifier such as a polymer modifier.

[0020] The asphalt composition of the present invention may further contain well-known raw materials incorporated in the asphalt composition as long as the object of the present invention is not impaired. For example, the asphalt composition may further contain aggregates such as crushed stone and sand, and / or fillers such as stone powder, and may be in the form of a so-called asphalt mixture (asphalt composite material). For the purpose of reducing environmental impact, the aggregate may be recycled asphalt aggregate.

[0021] In yet another aspect, the present invention also relates to a method for improving the water resistance and / or non-fluidity of asphalt, and the method includes a step of adding the compound of formula (1) to the asphalt. The addition amount of the compound of formula (1) is not particularly limited, but for example, it may be about 0.005 to about 0.5 by mass ratio with respect to the amount of asphalt used, and preferably about 0.03 to about 0.3. The temperature of the addition step is not particularly limited, but for example, it may be about 70°C to about 170°C, and preferably about 80°C to about 160°C.

[0022] Hereinafter, the present invention will be specifically described by way of examples, but the scope of the present invention is not limited to these examples.

Examples

[0023] 1. Preparation of Asphalt Composition and Its Water Resistance Test (1) In a glass container, straight asphalt 60 / 80 (StAs) and 1,5-anhydro-D-glucitol-2,3,4,6-tetrapalmitate (C16AG) were mixed at the mass ratios shown in Table 1 below.

Table 1

[0024] Each glass container was left standing in an oven at 130°C for 30 minutes under a nitrogen stream. The mixture was stirred well with a spatula for 30 seconds to prepare asphalt compositions A to D. Each composition was placed on a glass plate at about 0.1 g each and left to solidify at room temperature for 24 hours.

[0025] When observing the appearance of the solidified asphalt compositions, composition A had the luster characteristic of StAs, and composition B also showed luster, but the luster disappeared in compositions C and D. That is, in compositions B to D, as the addition amount of C16AG to StAs increased, the luster disappeared, and the overall appearance became uniform and without unevenness. Therefore, it was judged that C16AG was uniformly mixed with StAs.

[0026] Also, 10 μL of water droplets were placed on the above solidified asphalt compositions and left at room temperature for 1 hour. After the water droplets dried, the surface of the sample was observed. In composition A, a crater-like shape remained after the water droplet, but as the addition amount of C16AG increased, the depth of the crater gradually became shallower (compositions B and C), and no crater was formed in composition D. Therefore, it is considered that the surface structure of the asphalt composition consisting only of StAs changes when it comes into contact with water, but this change in the surface structure is reduced by the addition of C16AG, and the water resistance of the surface of the asphalt composition is improved.

[0027] 2. Preparation of Asphalt Composition and Its Water Resistance Test (2) Instead of C16AG, 1,5-anhydro-2,3,4,6-tetra-O-{4-[(1-oxotetradecyl)amino]butanoyl}-D-glucitol (C14GABA-AG) was used at the mass ratios shown in Table 2 below. Except that the oven temperature was set to 150°C, asphalt compositions E to G containing C14GABA-AG were prepared in the same manner as in Item 1 above and solidified on a glass plate.

Table 2

[0028] When observing the appearance of the solidified asphalt composition, it was judged that C14GABA-AG was uniformly mixed with StAs because the gloss disappeared and the overall appearance became uniform and unevenness-free as the addition amount of C14GABA-AG to StAs increased.

[0029] Also, when a water resistance test was conducted in the same manner as in Item 1 above, as the addition amount of C14GABA-AG increased, the craters caused by water droplets became smaller, and no craters were formed particularly in Composition F and Composition G. Therefore, it is considered that the water resistance of the surface of the asphalt composition was improved by C14GABA-AG.

[0030] 3. Preparation and Water Resistance Test of Asphalt Compositions Containing Other Oil Gelling Agents Attempts were made to prepare asphalt compositions in the same manner as in Item 1 above, except that various oil gelling agents (dextrin palmitate (Leopearl KL2), amino acid-based oil gelling agent GP1, 12-hydroxystearic acid, 1,12-dodecanedicarboxylic acid, or 1,3:2,4-di-(3,4-dimethylbenzylidene)-D-sorbitol) were used at 10% by mass based on the mass of StAs instead of C16AG. However, oil gelling agents other than 12-hydroxystearic acid did not dissolve in StAs under the condition of 130°C.

[0031] When an asphalt composition containing various oil gelling agents was solidified on a glass plate and the appearance was observed, the composition containing 12-hydroxystearic acid had a non-glossy, uniform, and non-uniform appearance as a whole. However, in the compositions containing other oil gelling agents, it was observed that the oil gelling agent remained in a granular state and was mixed in StAs, and the gloss peculiar to asphalt was also maintained.

[0032] Also, when a water resistance test was conducted in the same manner as in Item 1 above, craters were formed in all the asphalt compositions tested here, and the change in the surface structure of the asphalt composition due to water could not be prevented depending on the oil gelling agent used in this test. Therefore, it can be understood that the effect of improving the water resistance of the asphalt composition is an effect peculiar to the compound defined in the present invention.

[0033] 4. Non-fluidity test of asphalt composition (1) According to the procedures described in Items 1 and 2 above, asphalt compositions A to G were prepared in glass containers. After each composition was solidified, the glass container was turned upside down and left at room temperature for one week. Then, Composition A had dripped down along the wall from the bottom of the glass container, but Compositions B to G remained solid at the bottom of the glass container (Figure 1). Also, when the glass containers containing Asphalt Compositions A and E to G solidified at the bottom of the container were turned upside down and left at 60 °C, Composition A had dripped down along the wall after 30 minutes, but Compositions B to G remained solid at the bottom of the glass container (Figure 2). Therefore, it is considered that the non-fluidity of the asphalt composition was improved by C16AG or C14GABA-AG.

[0034] 5. Differential scanning calorimetry of asphalt composition Differential scanning calorimetry (DSC) was performed on C16AG alone or Asphalt Compositions A to D. The measurement was carried out using DSC3500 Sirius manufactured by NETZSCH under a nitrogen stream from -50 °C to 120 °C at a heating rate of 5.0 °C / min. The results are shown in Figure 3.

[0035] In the thermogram of the C16AG single component, an endothermic peak was observed at 76 °C, which corresponds to the melting temperature of C16AG. In Composition A, the DSC changed stepwise between 10 °C and 40 °C, which was considered to be due to the glass transition of asphalt. In Compositions B to D, in addition to the DSC change caused by the glass transition of asphalt, an endothermic peak considered to be due to the melting of C16AG was observed. Specifically, an endothermic peak was observed at 54 °C in Compositions B and C, and an endothermic peak was observed at 57 °C in Composition D. Since the melting temperature of C16AG mixed with asphalt is different from that of C16AG alone, it is considered that C16AG interacts with asphalt in Compositions B to D.

[0036] 6. Structure Observation by Atomic Force Microscopy The fine structures of Asphalt Compositions A to D were observed by atomic force microscopy. As the atomic force microscope, MFP-3D-BIO manufactured by Oxford Instruments was used, and as the cantilever, OMCL-240TS manufactured by Olympus was used. The results are shown in Fig. 4.

[0037] In Composition A, the bee structure peculiar to asphalt was observed, showing a typical structure of asphalt (Fig. 4a). In Compositions B to D, fibrous or layered C16AG structures were observed (Figs. 4b to d), and structures different from those of Composition A were formed.

[0038] 7. Tests by Asphalt Mixture Model In a glass container, StAs was mixed with C16AG at 10% by mass based on the mass of StAs. Four glass balls (with a diameter of about 15 mm) were placed in a glass container containing about 5 g of this mixture, and the container was left standing in an oven at 130 °C for 30 minutes under a nitrogen stream. The mixture was stirred well with a spatula to ensure that the C16AG-containing asphalt composition adhered well to the entire surface of the glass balls. Then, immediately after taking the glass balls out of the container, the four glass balls were assembled in the shape of a triangular pyramid and left at room temperature for 24 hours or more to allow adhesion, thereby preparing an asphalt composite material model of the present invention. For comparison, similar glass balls were prepared using an asphalt composition without C16AG (StAs only), assembled in the shape of a triangular pyramid, and adhered to prepare a control asphalt composite material model.

[0039] Each asphalt composite material model was placed on a hot plate set at 60 °C, and the changes were observed. In the control asphalt composite material model, the glass balls began to move gradually 20 minutes after being placed on the hot plate, and the triangular pyramid shape collapsed 40 minutes later (left in Figure 5). In the asphalt composite material model of the present invention, the glass balls did not flow even 40 minutes after being placed on the hot plate, and the triangular pyramid structure was maintained (right in Figure 5). Therefore, it was also confirmed by the asphalt composite material model that the addition of C16AG improves the non-fluidity of the asphalt composition.

[0040] In addition, each asphalt composite material model was placed in a water bath set at 60 °C, and the changes were observed. In the control asphalt composite material model, StAs began to peel off from the glass balls gradually 15 minutes after being placed in the water bath, and about 70% of the surface of the glass balls was exposed 30 minutes later (left in Figure 6). In the asphalt composite material model of the present invention, although StAs peeled off from the glass balls to some extent, the exposed surface of the glass balls was about 20% 30 minutes after being placed in the water bath (right in Figure 6), and the difference from the control asphalt composite material model was significant. Therefore, it was also confirmed by the asphalt composite material model that the addition of C16AG improves the water resistance of the asphalt composition.

[0041] 8. Preparation of Asphalt Composition and Its Water Resistance Test (3) Except that 1,5-anhydro-2,3,4,6-tetrastearate (C18AG) was used in the mass ratio described in Table 3 below instead of C16AG, asphalt compositions H to J containing C18AG were prepared in the same manner as in Item 1 above and solidified on a glass plate.

Table 3

[0042] When observing the appearance of the solidified asphalt composition, it was judged that C18AG was uniformly mixed with StAs because the gloss disappeared and the overall appearance became uniform and uneven as the addition amount of C18AG to StAs increased.

[0043] Also, when the water resistance test was conducted in the same manner as in Item 1 above, as the addition amount of C18AG increased, the crater formed by the water droplet became smaller, and particularly in Composition J, no crater was formed. Therefore, it is considered that the water resistance of the surface of the asphalt composition was improved by C18AG.

[0044] 9. Non-fluidity Test of Asphalt Composition (2) According to the procedure described in Item 8 above, asphalt compositions H to J were prepared in a glass container. After each composition was solidified, the glass container was turned upside down and left at room temperature for one week, but compositions H to J remained solid at the bottom of the glass container (Figure 7). Also, even when the glass container containing asphalt compositions H to J solidified at the bottom of the container was turned upside down and left at 60 °C, these compositions H to J remained solid at the bottom of the glass container (Figure 8). The asphalt composition without adding C18AG, even if it solidifies at the bottom of the glass container, will drip down along the wall when turned upside down (refer to the test result of Composition A in Item 4 above). Therefore, it is considered that the non-fluidity of the asphalt composition was improved by C18AG.

[0045] As described above, by using the compound of formula (1) described in this specification, it has been found that the production of the asphalt composition can be carried out at a relatively low temperature, and the water resistance and / or non-fluidity of the asphalt can be improved. Therefore, it becomes possible to improve the production environment of asphalt or to improve the durability of building materials using asphalt and the like.

Claims

1. Formula (1): 【Chemical 1】 （１） (A represents hydrogen or OR, each R is independently an acyl group derived from a linear saturated fatty acid having 10 to 22 carbon atoms, or each R is independently selected from the group consisting of hydrogen, a linear alkyl group having 10 to 22 carbon atoms, an acyl group derived from a linear saturated fatty acid having 10 to 22 carbon atoms, and an acyl group derived from a γ-aminobutyric acid derivative represented by the following formula: [Chemical 2] and n is 8 to 18, and at least one of R is an acyl group derived from the γ-aminobutyric acid derivative) An asphalt modifier comprising a compound of.

2. The compound is represented by formula (2) or (3): 【Chemical Formula 3】 （２） 【Chemical Formula 4】 （３） (The definition of each R is as described in Claim 1) The asphalt modifier according to Claim 1, represented by.

3. The asphalt modifier according to Claim 1 or 2, wherein one or less of R is hydrogen.

4. The asphalt modifier according to Claim 1 or 2, wherein all of R are simultaneously an acyl group derived from the linear saturated fatty acid or an acyl group derived from the γ-aminobutyric acid.

5. The asphalt modifier according to Claim 1 or 2, wherein n is 10 to 16.

6. Asphalt and formula (1): [Chemical Formula 5] （１） (A represents hydrogen or OR, each R is independently an acyl group derived from a linear saturated fatty acid having 10 to 22 carbon atoms, or each R is independently selected from the group consisting of hydrogen, a linear alkyl group having 10 to 22 carbon atoms, an acyl group derived from a linear saturated fatty acid having 10 to 22 carbon atoms, and an acyl group derived from a γ-aminobutyric acid derivative represented by the following formula: 【Chemical Formula 6】 and n is 8 to 18, and at least one of R is an acyl group derived from the γ-aminobutyric acid derivative) A composition comprising a compound of.

7. The composition according to Claim 6, wherein the content of the compound is 0.005 to 0.5 by mass ratio with respect to the content of the asphalt.

8. The composition according to Claim 6 or 7, which does not contain a polymer modifier.

9. The composition according to Claim 6 or 7, further comprising an additional asphalt modifier.

10. A method for improving the water resistance and / or non-fluidity of asphalt, comprising adding to asphalt a compound of formula (1): 【Chemical Formula 7】 （１） (A represents hydrogen or OR, each R is independently an acyl group derived from a linear saturated fatty acid having 10 to 22 carbon atoms, or Each R is independently selected from the group consisting of hydrogen, a linear alkyl group having 10 to 22 carbon atoms, an acyl group derived from a linear saturated fatty acid having 10 to 22 carbon atoms, and an acyl group derived from a γ-aminobutyric acid derivative represented by the following formula: 【Chemical 8】 n is from 8 to 18, and at least one of R is an acyl group derived from the γ-aminobutyric acid derivative). A method comprising the step of adding a compound of ).

Images