KR20040090885A - Plant mix type additive for modified asphalt - Google Patents

Abstract

PURPOSE: A plant mix type additive for a modified asphalt is provided to ensure a same or better physical property comparing to a physical property of a conventional polymeric modified asphalt and to facilitate a quality control. CONSTITUTION: The plant mix type additive for the modified asphalt comprises a process oil, 25 to 45 wt.% of a low softening point asphalt, 20 to 40 wt.% of a petroleum resin or thermoplastic resin, 20 to 55 wt.% of a thermoplastic elastomer(TPE) or rubber, 0.1 to 0.5 wt.% of a heat resistant antioxidant, 0.1 to 0.3 wt.% of an UV stabilizer and 0.2 to 0.6 wt.% of a viscosity depressant. The preparation method of the additive comprises the steps of: dispersing the process oil, asphalt, petroleum resin or thermoplastic resin homogeneously, adding the TPE or rubber thereto, further adding the antioxidant, UV stabilizer and viscosity depressant, dispersing sufficiently and forming into a particle having a diameter of 5 mm or less and a length of 2 cm or less.

Description

Plant mix type additive for modified asphalt}

The present invention relates to road pavement, but conventional asphalt pavement has been mainly constructed, but recently, due to improved road durability and reduced maintenance costs, such as polymer modified asphalt pavement, SMA (stone mastic asphalt) pavement, gus (GUSS) Modified asphalt pavements, such as asphalt pavements, are on the rise. However, various problems have arisen in the production and construction of such modified asphalt, so the popularization of production and construction is delayed. In the above-described problem, in order to effectively disperse the polymer used as the modifier in the case of the polymer-modified asphalt, since the polymer material is dispersed in the asphalt binder in advance, a separate storage tank for storing the modified asphalt is needed, and the modified asphalt is Because of poor storage stability, there is a limit to the storage period, so it is difficult to use. In addition, in the case of drainable and permeable asphalt, the viscosity of the modified asphalt used as the binder is high, and there are many problems in transport and storage. In addition, the polymer-modified asphalt is transported by the tank lorry, so at least 5 tons or more must be transported, so that a small amount of production is impossible, and there is always a residual amount in the storage tank, so quality control is very difficult. In the case of SMA (stone mastic asphalt) pavement, a fiber filler is used as a modifier in an existing asphalt binder. As the fiber filler has a large amount of oil absorption, the amount of asphalt used is high. There is a problem of bleeding, in which asphalt leaches onto the road surface.

Of course, plant mix type asphalt reforming additives have been developed and used in developed countries such as Japan, but these products have been reduced in productivity because they require about 2 to 4 minutes to be mixed with aggregates after they are put into ascon plants. Quality control is difficult due to damage, and the time required to produce one vehicle is more than two to four times the production time of general modified ascon. This problem is the cause of the secondary construction in the construction site.

According to the present invention, the polymer modifier used for the asphalt modification, various resins, process oil, low softening point asphalt, etc. are properly mixed and uniformly dispersed in advance, and then formed into particles having a diameter of 5 mm or less and a length of 2 cm or less, and this is an ascon mixing plant. The present invention suggests a method to solve the above-mentioned problems at the same time by adjusting the appropriate amount directly.

The present invention has been developed to solve such problems in the prior art as compared to the physical properties of the conventional polymer-modified asphalt, it is possible to secure more than the same physical properties, easy quality control and to be able to produce in all ascon factory To present.

In the present invention, the polymer-modified asphalt that is being used is produced and managed as a separate product for each purpose, and a separate storage tank is required for each product, and a small amount of production is impossible because the minimum transport unit is 5 tons or more. It also solves the disadvantages such as deterioration of quality due to long-term storage of the remaining amount in the tank and the inability to produce in an asphalt concrete plant without a modified asphalt binder storage tank, and is also used in advanced countries such as Japan. It also solves the disadvantages of productivity degradation, difficult quality control and temperature control due to the long beaming time of the modifying additive, and it has good reforming effect due to poor compatibility and storage stability with asphalt, but has many difficulties to use as a modifier. Radial Styrene-Butadiene-Styrene (hereinafter referred to as SBS) The purpose is to enable the use of rock copolymers.

The present invention according to the first aspect for achieving the above object is a process oil and low softening point asphalt 25 to 45% by weight and petroleum resin or thermoplastic resin 20 to 40% by weight in a temperature of 150 to 180 ℃ 20 to 55% by weight of thermoplastic elastomer (hereinafter referred to as 'TPE') or rubber is added thereto, and 0.1 to 0.5% by weight of heat resistant antioxidant, 0.1 to 0.3% by weight of UV stabilizer, and 0.2 to 0.6% of viscosity reducing agent. After additionally added to and then fully dispersed in a homogeneous phase at a temperature of 150 ~ 200 ℃ to implement a process for producing a plant mix type asphalt modifying additive consisting of forming a particle of less than 5mm in diameter, 2cm in length.

Hereinafter, preferred embodiments of the present invention will be described in detail. It should be noted that in the following description, only parts necessary for understanding the present invention will be described, and descriptions of other parts will be omitted so as not to distract from the gist of the present invention.

First of all, if you look at the concept of the present invention implemented above, it is possible to secure more than the same physical properties compared to the physical properties of the existing polymer modified asphalt, more easily control the quality, can be produced in all ascon facilities, small quantities, various grades It is to provide a method to produce a modified asphalt composition of. That is, process oil and low softening point asphalt 25 to 45% by weight and petroleum resin or thermoplastic resin 20 to 40% by weight are dispersed in a uniform phase at a temperature of 150 to 180 ℃, 20 to 55% by weight of TPE or rubber 0.1 to 0.5% by weight of heat resistant antioxidant, 0.1 to 0.3% by weight of UV stabilizer, and 0.2 to 0.6% of viscosity reducing agent were further added, and then sufficiently dispersed in a uniform phase at a temperature of 150 to 200 ° C., which was 5 mm or less in diameter, A method for producing a plant mix type asphalt modifying additive by molding into particles having a length of 2 cm or less is proposed.

Hereinafter, the present invention will be described in more detail.

Plant mix type asphalt modification additive according to the present invention is 25 to 45% by weight of process oil and low softening point asphalt, 20 to 40% by weight of petroleum resin or thermoplastic resin, 20 to 55% by weight of TPE or rubber, 0.1 to 0.5% by weight of heat resistant antioxidant %, An ultraviolet stabilizer of 0.1 to 0.3% by weight, and a viscosity reducing agent of 0.2 to 0.6%.

The role of each component used in the present invention is as follows. The process oil and low softening point asphalt first serve as a hot solvent for homogeneously dispersing the polymer material, preferably TPE and rubber. However, in the plant mix asphalt modification additive of the present invention, the process oil does not sufficiently digest the role of a high temperature solvent to uniformly disperse the TPE and rubber in producing the plant mix asphalt modification additive when the composition is less than 25% by weight. As a result, undispersed TPE and rubber remain in the additive, making it difficult to sufficiently secure the physical properties of the modified asphalt composition and quality control. In addition, in the plant mix asphalt modification additive of the present invention, the process oil is easy to disperse the TPE and rubber in the preparation of the plant mix asphalt modification additive when the composition exceeds 45% by weight, but the plant mix asphalt modification additive It is very difficult to make particles into particles having a diameter of 5 mm or less and a length of 2 cm or less, making it difficult to commercialize them.

In addition, the petroleum resin and the thermoplastic resin play a role of improving adhesion between aggregates in the polymer-modified asphalt composition, securing dispersion fluidity of TPE and rubber, and improving hardness and durability of the binder itself. However, in the plant mix type asphalt modifying additive of the present invention, when the composition of the petroleum resin and the thermoplastic resin is less than 20% by weight, it is difficult to secure the dispersion fluidity of TPE and rubber in manufacturing the plant mix type asphalt modifying additive. Since sufficient adhesive strength is not given, problems such as aggregate detachment may occur. In addition, the petroleum resin and the thermoplastic resin in the plant mix asphalt modifying additive of the present invention, when the composition exceeds 40% by weight, the dispersion fluidity and adhesion of TPE and rubber are increased in manufacturing the plant mix asphalt modifying additive. Because of this, there is a problem that the rigidity is relatively strengthened and the elasticity of the modified asphalt is not sufficiently secured.

In addition, the TPE and rubber give low temperature elasticity and high temperature durability to the pavement in the polymer modified asphalt composition, thereby providing physical properties corresponding to low temperature cracking and plastic deformation of the roadway. However, in the plant mix asphalt modifying additive of the present invention, when the composition is less than 20% by weight, TPE and rubber are difficult to secure elasticity and durability of the modified asphalt composition when preparing the plant mix asphalt modifying additive. It becomes impossible to play a role as an additive. In addition, in the plant mix type asphalt modifying additive of the present invention, when the composition is more than 55% by weight of TPE and rubber, it is difficult to uniformly disperse the production of the plant mix type asphalt modifying additive, thereby reducing the quality of the modified asphalt composition. There is a problem.

In addition, in the present invention, the heat resistant antioxidant is added in an amount of 0.1 to 0.5% by weight to prevent oxidation and deterioration at high temperatures of the TPE and rubber, and the UV stabilizer is ultraviolet aging due to sunlight when the modified asphalt composition is paved on the road. In order to prevent the addition of 0.1 to 0.3% by weight, the viscosity-lowering agent maintains a very high viscosity even at high temperatures in the production of plant mix asphalt modifying additives, so it is not easy to disperse TPE and rubber to add 0.2 to 0.6% It is used as a means for facilitating manufacture by input.

As described above, the materials constituting the present invention will be described in detail. Process oil is a hydrocarbon compound that is used as an auxiliary component to improve processability during manufacturing of a specific product as a component of an industrial product, unlike general lubricants disposed of after use. And paraffin, naphthenic and aromatic based on their chemical composition. In addition, the low softening point asphalt refers to vacuum distillation and atmospheric distillation residue oil as residue left after refining crude oil, and softening point of 55 ° C. or less and penetration of 60 or more are used. Petroleum resin refers to petroleum-based hydrocarbon resin, it can be used a softening point of 90 ~ 150 ℃. The thermoplastic resin softens when heated to generate plasticity, but returns to its original solid when cooled, and is a polymer in which unit components are linearly bonded, and when cooled after molding, the thermoplastic resin solidifies in a state of being maintained. . Examples thereof include polyethylene resin (hereinafter referred to as 'PE'), polypropylene resin (hereinafter referred to as 'PP'), ethyl-vinyl-acetate resin (hereinafter referred to as 'EVA'), and atactic polypropylene resin. (Hereinafter referred to as 'APP'), thermo-plastic-olefin resin (hereinafter referred to as 'TPO'), PE wax, PP wax and the like can be used. The thermoplastic elastomer, like the thermoplastic resin, softens when heated to generate plasticity and returns to the original solid when cooled, but is characterized by exhibiting abundant elasticity in the solid state unlike the thermoplastic resin in the solid state. Linear SBS, radial type SBS, etc. can be used as the kind. In addition, the rubber has no heat plasticity such as a thermoplastic resin or a thermoplastic elastomer, but is characterized by maintaining elasticity at low and high temperatures and excellent durability. And unvulcanized rubber is characterized in that it can be dispersed in oils and resins by rubbing or rubbing with sufficient physical force from the outside. As its type, natural latex, styrene-butadiene rubber (hereinafter referred to as 'SBR') latex, SBS, and isoprene rubber can be used.

On the other hand, in the method for producing a plant mix type asphalt modifying additive according to the present invention, process oil and low softening point asphalt are added to a mixing tank that can be heated and stirred, and then maintained at a temperature of 150 to 180 ° C. while stirring. Dispersing in a homogeneous phase while maintaining the temperature at 150 ~ 180 ℃ while adding and stirring the resin, while adding a TPE or rubber to it while maintaining agitation, heat-resistant antioxidant, UV stabilizer, viscosity lowering agent and then 150 ~ 200 After sufficiently dispersed in a uniform phase at a temperature of ℃ ℃ it is molded into particles of diameter 5mm or less, length 2cm or less to complete the plant mix asphalt modification additive.

Hereinafter, the present invention will be described in detail based on the preferred embodiments of the present invention, but the present invention is not limited to the embodiments.

{Example 1}

40% by weight of process oil and low softening point asphalt in a 1: 1 ratio were added to the mixing tank that can be heated and stirred, while maintaining the temperature at 150 to 180 ° C while stirring, and 30% by weight of petroleum resin having a softening point of 150 ° C. While stirring, while maintaining the temperature at 150 ~ 180 ℃ dispersed in a homogeneous phase, while maintaining the stirring, 30 wt% of Radial-type SBS is added thereto, 0.3 wt% of heat resistant antioxidant, 0.2 wt% of UV stabilizer, After adding 0.3 wt% of a viscosity lowering agent, the mixture was sufficiently dispersed in a uniform phase at a temperature of 150 to 200 ° C., and then molded into particles having a diameter of 5 mm or less and a length of 2 cm or less to prepare a plant mix asphalt modifying additive. At this time, the physical properties of the plant mix asphalt modification additive prepared by the above-described method is shown in detail in Table 1.

{Table 1}

On the other hand, by applying the plant mix-type asphalt modification additive prepared by the above-described method of {Example 1} to the general surface compactness asphalt composition, the modified asphalt composition and the general modified asphalt composition prepared by adding 1% by weight to the total amount of asphalt composition The asphalt compositions were compared and shown in {Table 2}.

{Table 2}

As described above, the present invention overcomes the limitations of the premixed modified asphalt binders that have been used in the past, and can produce modified asphalt compositions wherever an asphalt concrete plant is located without a separate storage facility. In addition, by controlling the addition amount of the plant mix-type asphalt modified additive prepared by the present invention, it is possible to produce a variety of graded asphalt composition suitable for the design and specification of each construction site, thereby greatly contribute to the popularization of modified asphalt pavement in Korea. It is expected to be.

In particular, the road pavement is paved with a modified asphalt composition through the present invention can be expected to reduce the significant maintenance and repair costs by improving the durability of the road to extend the life.

Claims (1)

In plant mix type asphalt modification additive, 25 to 45% by weight of process oil and low softening point asphalt and 20 to 40% by weight of petroleum resin or thermoplastic resin are uniformly dispersed at a temperature of 150 to 180 ° C, and 20 to 55% by weight of TPE or rubber is added thereto. 0.1 to 0.5% by weight of heat resistant antioxidant, 0.1 to 0.3% by weight of UV stabilizer, and 0.2 to 0.6% of viscosity lowering agent were further added, and then sufficiently dispersed in a uniform phase at a temperature of 150 to 200 ° C, which was 5 mm in diameter or less. Plant mix asphalt modification additive, characterized in that the molding process of less than 2cm