JPH0254862B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a bituminous composition with improved strength properties, and more particularly to a bituminous composition comprising bituminous material and an ionomer resin. [Prior art] Bituminous material has been widely used as road paving material, roofing material, sealing material, coating material, binding material, etc., but it liquefies at high temperatures and is highly workable, and it cannot be used at room temperature or low temperature range. In this method, the basic properties of bituminous material are effectively utilized, such as being solid, having binding strength, exhibiting strength, and being inexpensive. However, on the other hand, these basic characteristics of bituminous material were also its drawbacks. In other words, deformation due to plastic flow becomes a problem during high temperatures such as summer, and problems such as cracking due to brittle fracture occur during cold weather such as winter. To solve these problems, ethylene vinyl acetate copolymer (hereinafter referred to as
Abbreviated as EVA. ) Thermoplastic resins such as polyethylene (hereinafter abbreviated as PE), ethylene ethyl acrylate copolymer (hereinafter simply abbreviated as EEA), or styrene-butadiene rubber (hereinafter abbreviated as SBR), styrene. Butadiene block copolymer rubber (hereinafter abbreviated as SBSR)
This problem has been dealt with by technical means of modifying the bituminous material by adding rubber such as chloroprene rubber (hereinafter abbreviated as CR) to the bituminous material, either singly or in combination. However, the modification effect achieved by these means is not sufficient; for example, when using thermoplastic resins such as EVA, PE, and EEA, they lack tensile strength and elongation ability, and furthermore, in compositions containing a large amount of them, However, there are disadvantages in that the miscibility with bituminous material and adhesion are significantly reduced, and the shrinkage during heating and cooling becomes extremely large. Furthermore, when rubber is added, the elongation ability is large, but as the amount added increases, the viscosity increases significantly, so there is a problem with the amount added from the viewpoint of workability, and if you try to add more than this, the rubber The problem is that it undergoes significant thermal alteration and becomes liquefied or gelled. It is also known to modify the properties of a bituminous composition by adding a thermosetting resin (epoxy, polyurethane, etc.) to the bituminous material, but in this case, the modified composition may become too brittle or It takes several days of curing to complete hardening, and although some materials can be remelted and remolded to some extent by heating once hardened, most have drawbacks such as not being able to obtain their original physical properties. be. As described above, the effect of modifying bituminous substances by conventional technical means cannot be said to be sufficient, and as a result, the uses of bituminous substances are currently limited. [Problems to be Solved by the Invention] Therefore, the present invention aims to solve the above-mentioned drawbacks of bituminous materials, and provides a bituminous composition that can greatly improve mechanical properties such as tensile strength and elongation. It's about doing. Another object of the present invention is to provide a bituminous composition comprising a compatible composition of bituminous material and an ionomer resin and having improved thermal properties. [Means for Solving the Problems] As a result of extensive research, the present inventors have found good results in a composition consisting of bituminous material and an ionomer resin, and have achieved the present invention. The present invention provides a bituminous composition in which 70 to 30 parts by weight of bituminous material (hereinafter simply abbreviated as "parts") and 30 to 70 parts of ionomer resin are dissolved, thereby achieving great strength properties. be. The bituminous substance is
When measured according to JIS-K2531, the softening point is 30~
130°C, preferably a softening point of 40-90°C, and is solid or semi-solid at room temperature (20-25°C). This bituminous material is selected from straight asphalt, natural asphalt, semi-blown asphalt, blown asphalt, pitches, and petroleum resin binders for color pavement, which are solid or semi-solid at room temperature. Among these, straight asphalt, natural asphalt, semi-blown asphalt, blown asphalt, and petroleum resin binders for colored pavement are desirable because they have good compatibility with ionomer resins and have a large effect on improving strength properties. Ionomer resin refers to a group of polymers in which molecular chains are cross-linked with metal ions using carboxyl groups in a copolymer of α-olefin and a monomer having carboxylic acid. Any ionomer resin can be used. Among these, ionomer resins in which the molecules of ethylene-methacrylic acid copolymer are cross-linked with metal ions, especially Zn ions, have good compatibility with bituminous materials, are excellent in workability, and have a large effect on modifying the strength properties of bituminous materials. It is preferable. The shape of the ionomer resin at room temperature may be granular, flake, pellet, or powder, and there is no significant difference in the modifying effect of the bituminous composition depending on the shape. However, considering workability and processability, A powdered resin is preferable. Although ionomer resin is a thermoplastic resin, it has metal ion bonds in the temperature range where it solidifies.
It is very strong like a thermosetting resin, has moderate elasticity and flexibility, and its ionic bonds weaken at high temperatures.
It has the property of being melted like a thermoplastic resin. Therefore, a bituminous material modified with an ionomer resin, that is, a bituminous composition, has excellent tensile strength and elongation properties. A bituminous composition with good strength properties is produced by adding 30 to 70 parts of bituminous material to 70 to 30 parts of ionomer resin and heating at 170°C to 200°C.
It can be obtained by sufficiently heating and kneading at a high temperature of °C to sufficiently dissolve the two. Mixing of the two can be achieved, for example, by preparing a master batch in which the entire amount of the ionomer resin is mixed with a small amount of bituminous material, then adding the remaining bituminous material to this, and then kneading the mixture until they are sufficiently compatible. In addition, at the time of kneading, an antifoaming agent, an anti-aging agent, an anti-peeling agent, etc. may be added as necessary. Furthermore, by adding carbon black powder, lubricating oil, or other plasticizers as necessary, the viscosity during kneading can be lowered and workability and processability can be improved. However, if the amount of these additives increases, in the case of carbon black powder, the resulting composition becomes brittle, and in the case of lubricating oil, although the elongation ability increases, the strength decreases.
Desirably, the amount of these additions is about 5% at most. The bituminous composition may also contain 2
It is also possible to add pigments of the order of ~10%. The amount of ionomer resin added affects the strength properties of the bituminous composition, i.e. tensile strength and elongation ability.
Since no special synergistic effect is observed with 30 copies or less or 70 copies or more, the range must be between 30 copies and 70 copies. [Test Examples] Test examples for obtaining the present invention will be described below. Test Example 1 For bituminous compositions modified with the thermoplastic resins shown in sample numbers a to d and the rubber shown in sample number e according to the formulations in Table 1, the resin or rubber was first modified. 160-170 for the entire portion
A small amount of bituminous material heated and melted at ℃ (40~
50% by weight) was heated and kneaded until uniform, and the remaining bituminous material was added in a predetermined amount and thoroughly kneaded again, and the thermosetting resin shown in sample number f was used. For the main agent (flexible epoxy resin) and curing agent (aliphatic amine)
The bituminous material heated and melted at a ratio of 41:59 and thoroughly kneaded were made into sheets with a thickness of approximately 5 mm (sample number f was cured at 60℃ for 7 days) and then No. 2 shape was obtained. Create a dumbbell-shaped test piece and set the specimen temperature to -10, 0, 10, 20, 40℃
About Servo Pulsar Lab−0.1U
(manufactured by Shimadzu Corporation) at a tensile speed of 8.33 mm/
A tensile test was conducted at sec, and the results of the tensile strength and elongation determined using the formula shown below are shown in Table 2. Tensile strength (Kg/cm ² ) = Maximum load (Kg) / Cross-sectional area of test piece (cm ² ) Elongation (%) = Length between gauge lines at maximum load (mm) - [Gauge distance (mm) )] / Gauge distance (mm) x 100 Straight asphalt with a softening point of 49.5 to 47.5°C (penetration of 60 to 80) is used as the bituminous material, and metal ions are used between the molecules of ethylene-methacrylic acid copolymer. The cross-linked ionomer resin was Himilan #1702 (manufactured by Mitsui Polychemicals, a trade name of ionomer resin cross-linked with Zn ions) powder, and the EVA used for comparison was Evaflex #420 (manufactured by Mitsui Polychemicals). , ethylene vinyl acetate copolymer (trade name) powder, and as EEA NUC copolymer DPDU #9169
(manufactured by Nippon Unicar, trade name of ethylene ethyl acrylate copolymer) powder, Yucalon JX-10 (manufactured by Mitsubishi Yuka, trade name of polyethylene) powder for PE, and Califrex KX-10 for SBSR. 65 (manufactured by Shell Chemical Co., USA, trade name of styrene-butadiene block copolymer) was used, and as for the epoxy resin, a liquid version of Spik (manufactured by Kao Soap Co., Ltd., trade name) was used.

【table】

【table】

[Table] As is clear from Table 2, the strength characteristics of the bituminous composition of Test Example 1, that is, the tensile strength, in the low temperature range (-10℃, 0℃) 4 to 5 times that of a bituminous composition modified with EVA, approximately 13 times that of a bituminous composition modified with SBSR rubber, and a thermosetting resin. 12-14% compared to the modified epoxy bituminous composition.
An increase in elongation was observed, and even at this time, an increase of 44% in the epoxy-based bituminous composition, and an increase of 2 to 3 times that in the bituminous composition modified with PE was observed. In addition, the tensile strength in the medium temperature range (40℃) is 3 to 5 higher than that of bituminous compositions modified with EEA and EVA, which are common thermoplastic resins.
approximately 15 times that of a bituminous composition modified with SBSR rubber, and approximately 8 times that of an epoxy bituminous composition modified with a thermosetting resin. An increase in the number of children was observed. Test Example 2 The bituminous material was straight asphalt (with a softening point of 49.5 to 47.5°C), where 30 parts (all powder) of the ionomer resin used in Test Example 2 (Himilan #1702, the same as Test Example 1) and 70 parts of bituminous material were used. Blown asphalt (penetration 60-80), softening point 80.0-89.0℃ (penetration 20-30), softening point 110.0-130.0
Table 3 shows the results of a tensile test carried out in the same manner as in Test Example 1 on a tensile test sample of 10.degree. In this experimental example, we looked at the effect of the different bituminous materials used on the strength properties of the finished bituminous composition, and although there may be slight differences in the strength property values, various bituminous materials can be used. It was revealed that.

[Table] Test Example 3 In a blend of 65 parts of bituminous material (straight asphalt with a softening point of 49.5 to 47.5°C, penetration of 60 to 80) and 35 parts of ionomer resin (powder, Hymilan), the type of ionomer resin was changed, A tensile test was conducted in the same manner as in Test Example 1 above. The results of this tensile test are shown in Table 4. In this test example, the product numbers of ionomer resin Himilan were #1652, #1702, #1706,
#1855 has metal ions consisting of Zn ions, and Himilan's product number is #1605.
The metal ions of #1707 and #1856 are Na ions. In this Test Example 3, we investigated the effects of different types of ionomer resins, especially differences in their metal ions, on the strength properties of the resulting bituminous composition, and it was revealed that there was almost no difference ( (See Table 4). However, from the point of view of mixability, durability, etc., metal ions in ionomer resins are
The Zn ion type is more preferable than the Na ion type, and more preferably, it has a melt index of 14 and physical properties close to the VICAT softening point of 61°C, such as product number #1702.

[Table] Test Example 4 Comparison with EVA (Evaflex #420) and epoxy resin (Spic) in a formulation of 100 to 0 parts of bituminous material (straight asphalt with a softening point of 49.5 to 47.5°C, penetration of 60 to 80) , the blending of ionomer resin (Himilan #1702) is from 0 parts to
Tensile tests and elongation tests were conducted when the composition was changed up to 100 parts. The test results are shown in FIGS. 1 to 10. Furthermore, Figure 1 shows the tensile strength at -10℃, Figure 2 shows the elongation at -10℃, Figure 3 shows the tensile strength at 0℃, Figure 4 shows the elongation at 0℃, and Figure 5 shows the elongation at +10℃. Figure 6 shows the elongation at +10°C, Figure 7 shows the tensile strength at +20°C, Figure 8 shows the elongation at +20°C, Figure 9 shows the tensile strength at +40°C, and Figure 10 shows the tensile strength at +40°C. The results are shown for the elongation at ℃, and in each of the graphs in Figures 1 to 10, Graph 1 is for ionomer resin, Graph 2 is for EVA, and Graph 3 is for epoxy resin. The results of Test Example 4 indicate that the bituminous composition made of 70 to 30 parts of bituminous material and 30 to 70 parts of ionomer resin is particularly excellent in tensile strength and elongation properties at -10°C and 10°C. Recognize. Ionomer resins provide much greater strength properties than those estimated from the tensile strength or elongation of bituminous material and ionomer resin alone, that is, a significant synergistic effect. On the other hand, when using EVA, a common thermoplastic resin, as a comparison, the elongation becomes relatively large as the amount added increases, but
The tensile strength is low, and it is not possible to see any additivity beyond the level corresponding to the amount added. In addition, in bituminous compositions containing epoxy resin, which is a thermosetting resin, the tensile strength is high in the region where the amount added is large, but the elongation is extremely small and no effects other than additivity are observed. It became clear. For example, 70 to 30 parts of bituminous material and 30 to 30 parts of ionomer resin.
A bituminous composition consisting of 70 parts has a tensile strength of -10°C.
and 124.2 to 201.9 Kg/cm ² at temperature, and 59.8 to 13.67 Kg/cm ² at 10°C. Test Example 5 The relationship between the blending amount of bituminous material and ionomer resin in a bituminous composition and the softening point of the composition was investigated, and the results are shown in FIG. 11. That is, the relationship between the ionomer resin addition rate and the softening point of the bituminous composition is as shown in Table 5.

〔Effect of the invention〕

The bituminous composition of the present invention can be used, for example, at -10°C or 0°C.
It has high tensile strength in the low-temperature range of 40°C and in the medium-temperature range of, for example, 40°C, so unlike bituminous materials, it does not become soft or lose its bonding strength even at high temperatures in the summer, and even in the cold winter. It does not become brittle, has excellent mechanical properties and thermal properties, and overcomes the inherent drawbacks of bituminous material. Since the bituminous composition of the present invention has the properties of a thermoplastic resin based on the ionomer resin blended into it, it can be softened again by heating, and once used, it can be reused or reused. It is available and convenient. Therefore, the bituminous composition according to the present invention is widely used in various applications such as plastic materials, rubber materials, road paving materials, and construction materials (roofing materials and sealing materials).

[Brief explanation of drawings]

Figures 1 to 10 show the strength characteristics of each bituminous composition in Test Example 4. Figure 1 is a graph showing the tensile strength at -10°C, and Figure 2 is a graph showing the tensile strength at -10°C. A graph showing elongation properties, Figure 3 is a graph showing tensile strength at 0°C, Figure 4 is a graph showing tensile strength at 0°C.
Graph showing elongation properties at °C, Figure 5 is +10
Graph showing tensile strength at °C, Figure 6 is +10
Graph showing elongation properties at °C, Figure 7 is +20
Graph showing tensile strength at °C, Figure 8 is +20
Graph showing elongation properties at °C, Figure 9 is +40
Graph showing tensile strength at ℃, Figure 10 is 40
It is a graph showing elongation characteristics at °C. 1st
Figure 1 is a graph showing the relationship between the amount of resin added and the softening point of the bituminous composition of Test Example 5.

Claims (1)

[Scope of Claims] 1. 70 to 30 parts by weight of bituminous material having a softening point of 30 to 130°C, and 30 to 70 parts by weight of an ionomer resin in which the molecules of an ethylene-methacrylic acid copolymer are cross-linked with metal ions, are compatible. A bituminous composition characterized by being dissolved.