KR101123783B1 - Polymer modified warm-mix asphalt additive, asphalt using the same and method for manufacturing warm-mix asphalt mixture using the same - Google Patents

Abstract

PURPOSE: A polymer modified warm-mix asphalt additive is provided to have excellent dispersity to asphalt, thereby minimizing the use of fiber additives, to restrain the drain-down phenomenon of asphalt, and to solve the complexity of processes. CONSTITUTION: A polymer modified warm-mix asphalt additive comprises 100.0 parts by weight of linear or branched styrene-butadiene-styrene block copolymer of which weight average molecular weight is 50,000-130,000 g/mol. 5-60 parts by weight of tackifying resin, 5-40 parts by weight of process oil, 20-100 parts by weight polyethylene wax of which melting point is 95-125 °C, and melt viscosity is 80-450 cPs at 140 °C, 5-50 parts by weight of a viscosity improver, and 30-150 parts by weight of cellulose fiber of which length is 0.01-8 mm, thickness is 7-80 micron, and weight average length is 1.53 mm/g.

Description

POLYMER MODIFIED WARM-MIX ASPHALT ADDITIVE, ASPHALT USING THE SAME AND METHOD FOR MANUFACTURING WARM-MIX ASPHALT MIXTURE USING THE SAME}

The present invention relates to a polymer-modified neutralizing additive incorporating cellulose fiber that can shorten the dispersion time, prevent the drainage of asphalt, and reduce the production and packaging temperature of the asphalt mixture, and a method for producing the asphalt and asphalt mixture using the same. It is about.

Asphalt Mixture is commonly called ascon, and after adding asphalt, aggregate, filler, etc. to the Asphalt Mixing Plant, these materials are put at 160-180 ° C. After being manufactured by heating to a high temperature, the process is cooled to room temperature in the road installation and compaction process.

Therefore, not only a large amount of energy is required for high temperature heating, but there is a problem that emissions of harmful gases such as carbon dioxide, sulfur oxides, and nitrogen oxides increase during the manufacture and construction of the asphalt mixture. In addition, since the road paving takes a long time to cool the high temperature asphalt mixture to room temperature, there is a problem that the traffic opening time is delayed, and workers are exposed to the risk of safety accidents.

Recently, in order to solve such a problem, a warm temperature asphalt mixture (Warm-) which mixes and compacts the asphalt mixture at a temperature of 20-40 ° C. lower than that of a conventional heated asphalt mixture (HMA) without deteriorating the physical properties of the asphalt. Research on Mix Asphalt Mixture (WMA) has been actively conducted, and there is a need for development of a neutralizing additive for a medium-temperature asphalt mixture having more improved performance.

On the other hand, asphalt is black at room temperature and has a very high viscosity in semi-solid state, and is classified into various grades based on its rigidity. Asphalt penetration test results of ASTM D946 and PG grades of ASTM D6373 are used. Asphalt can be classified.

Asphalt has different characteristics depending on the temperature, and at high temperatures, it becomes highly viscous and soft, while it is hard at low temperatures, and thus has good cracking properties. Therefore, when manufacturing ascon with asphalt having such characteristics and constructing it on the road, high temperature firing of ascon occurs when the air temperature rises as in summer, and low temperature of ascon when the air temperature decreases as in winter. There is a problem that causes cracking.

In order to improve the temperature characteristics of such asphalt, modified asphalt which has improved physical properties by mixing various additives with asphalt is widely used. The method of manufacturing modified asphalt for road is a wet type in which a pellet or crumb-type additive is added to asphalt in a large melting facility and melted at a high temperature, and then transported to an asphalt concrete plant to mix aggregate and asphalt, and aggregate in an asphalt concrete plant. When mixing asphalt with additives can be divided into dry type for producing ascone.

The wet type is generally used for pavement as it is suitable for mass production. However, if the transport distance is far, the asphalt may age and cause performance deterioration. In the case of using a small amount of asphalt due to the short paving interval, it may not be suitable for process operation, and phase separation may occur in which additives and asphalt are separated during storage or transport. Can be.

In the dry type, there is no storage process, so it is possible to minimize the deterioration of physical properties due to high temperature in the phase separation phenomenon and manufacturing process, and the short section pavement, road pavement, road maintenance and drainage that are difficult to apply wet type It can be widely used for special asphalt pavement. In particular, in the case of dry type, it is important that the additives are dispersed in asphalt in a short time, but additives for improving the physical properties of currently used asphalt have a limitation in dispersion speed. Accordingly, there is a need for developing additives with improved dispersibility that can be usefully used for dry mixing of asphalt mixtures.

On the other hand, coarse aggregates are used to make the drainage asphalt pavement method or the interlocking between the aggregates ideally to prevent water accumulation in the rain when the rain, crushed mastic asphalt to increase the resistance to plastic deformation and to induce crack delay (Stone Mastic Asphalt, hereinafter also referred to as 'SMA') In the pavement method, etc., a problem may occur in which the aggregate is detached from the asphalt after construction due to the "drain-down" phenomenon in which asphalt flows down from the aggregate. . In order to solve this problem, a fiber additive mainly composed of cellulose fiber, for example, "VIOTOP" sold by JRS, Germany, and "asconcell" sold by Korea S.S.

However, in the case of producing a medium-temperature asphalt mixture using such a fiber additive, there is a problem that the manufacturing cost of the production of ascon is increased due to additional manpower input and facility investment according to the additive input separately.

Therefore, the dispersion speed is high so that it can be applied to dry mixing of the modified asphalt mixture, while effectively suppressing the drain down phenomenon of the asphalt, minimizing the use of fiber additives, improving the cost problem due to the separate injection, and preventing the lowering of low temperature properties, There is a need to develop a neutralizing additive capable of efficiently lowering the mixing and compaction temperature of asphalt and aggregate, and asphalt using the same.

The present invention is excellent in dispersibility to minimize the use of fiber additives, to suppress the drain down phenomenon of asphalt, to solve the complexity of the process, and to prevent the low temperature properties, it is possible to efficiently reduce the mixing and compaction temperature of asphalt and aggregate An object of the present invention is to provide a polymer-modified neutralizing additive incorporating cellulose fiber and a method for preparing asphalt and asphalt mixture using the same.

In order to solve the above problems, the polymer-modified neutralizing additive incorporating the cellulose fiber of the present invention includes: iii) styrene-butadiene-styrene block copolymer; Ii) 5 to 60 parts by weight of a tackifying resin based on 100 parts by weight of the styrene-butadiene-styrene block copolymer; Iii) 5-40 parts by weight of process oil, based on 100 parts by weight of the styrene-butadiene-styrene block copolymer; Iii) 20 to 100 parts by weight of polyethylene wax based on 100 parts by weight of the styrene-butadiene-styrene block copolymer; V) 5 to 50 parts by weight of a viscosity improving agent based on 100 parts by weight of the styrene-butadiene-styrene block copolymer; And iii) 30 to 150 parts by weight of cellulose fiber based on 100 parts by weight of the styrene-butadiene-styrene block copolymer.

In addition, the method for producing a polymer-modified neutralizing additive incorporating the cellulose fiber of the present invention is iii) 5 to 60 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene block copolymer and the styrene-butadiene-styrene block copolymer. Melt mixing a tackifying resin, 5-40 parts by weight of process oil, 20-100 parts by weight of polyethylene wax, 5-50 parts by weight of viscosity improver, and 30-150 parts by weight of cellulose fiber; And ii) molding the molten mixture formed in step iii).

In addition, the asphalt using the polymer-modified neutralization additive incorporating the cellulose fiber of the present invention is iii) 3 to 20% by weight of the polymer-modified neutralization additive incorporating the cellulose fiber; And ii) 80 to 97% by weight asphalt.

In addition, the method for producing an asphalt mixture using the polymer-modified neutralizing additive incorporating the cellulose fiber of the present invention comprises the steps of: i) preparing a polymer-modifying neutralizing additive incorporating cellulose fiber according to the above method; And ii) melt mixing the neutralizing additive with asphalt and aggregate, wherein the weight ratio of the polymer-modified neutralizing additive incorporating the asphalt and the cellulose fiber is in the range of 80:20 to 97: 3. It is done.

The present invention improves the dispersibility to asphalt by using a polymer-modified neutralizing additive incorporating cellulose fiber, and thus may be usefully applied to dry mixing of asphalt mixture.

In addition, while effectively suppressing the draindown phenomenon of asphalt, it is possible to minimize the amount of the fiber additive and improve the cost problem of the separate input.

Furthermore, the preparation and compaction temperature of the asphalt mixture can be efficiently lowered without deteriorating physical properties, thereby minimizing the emission of harmful gases such as carbon dioxide, sulfur oxides, and nitrogen oxides.

Hereinafter, preferred embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the technical idea of the present invention.

The polymer-modified neutralizing additive incorporating cellulose fiber according to an embodiment of the present invention may include iii) styrene-butadiene-styrene block copolymer; Ii) 5 to 60 parts by weight of a tackifying resin based on 100 parts by weight of the styrene-butadiene-styrene block copolymer; Iii) 5-40 parts by weight of process oil, based on 100 parts by weight of the styrene-butadiene-styrene block copolymer; Iii) 20 to 100 parts by weight of polyethylene wax based on 100 parts by weight of the styrene-butadiene-styrene block copolymer; V) 5 to 50 parts by weight of a viscosity improving agent based on 100 parts by weight of the styrene-butadiene-styrene block copolymer; And iii) 30 to 150 parts by weight of cellulose fiber based on 100 parts by weight of the styrene-butadiene-styrene block copolymer.

The styrene-butadiene-styrene block copolymer included in the polymer-modified neutralizing additive incorporating the cellulose fiber of the present invention is used as an asphalt modifier for improving the physical properties of asphalt with temperature.

The styrene-butadiene-styrene block copolymer may be used without particular limitation as long as it is generally used in the art, but a linear or branched copolymer having a weight average molecular weight of 50,000 to 130,000 g / mol, preferably 65,000 More preferably 95,000 g / mol. If the weight average molecular weight is less than 50,000 g / mol is not enough asphalt modification effect, if it exceeds 130,000 g / mol viscosity and phase transition temperature is too high to be difficult to melt in asphalt in the asphalt mixture production temperature range.

The styrene content of the styrene-butadiene-styrene block copolymer is preferably 10 to 50% by weight, more preferably 20 to 45% by weight. When the styrene content of the styrene-butadiene-styrene block copolymer is less than 10% by weight, the elasticity is insufficient, so that physical properties such as softening point are reduced during asphalt modification, and when it exceeds 50% by weight, the plastic property becomes strong and the asphalt modification effect is improved. Not enough problems can occur.

The tackifying resin included in the polymer-modified neutralizing additive incorporating the cellulose fiber of the present invention serves to improve the physical properties of the asphalt mixture by increasing the adhesive force between the asphalt and the aggregate when preparing the asphalt mixture.

The tackifying resin is preferably included in the range of 5 to 60 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene block copolymer. When the amount of the tackifying resin is less than 5 parts by weight with respect to 100 parts by weight of the styrene-butadiene-styrene block copolymer, the adhesion between the asphalt and the aggregate is weak during the production of the asphalt mixture, and when the amount is greater than 60 parts by weight, the aggregation phenomenon occurs. Machining becomes difficult and leads to additional processing cost increase.

Tackifying resins include aromatic hydrocarbon petroleum resins, aliphatic hydrocarbon petroleum resins, dicyclopentadiene petroleum resins, polybutenes, coumarone-indene resins, polyterpene resins, terpene phenol resins, rosin, rosin esters, and hydrogens thereof It is preferable that it is at least 1 type selected from the group which consists of an additive.

In particular, it is preferable to use an aromatic hydrocarbon-based petroleum resin having a softening point of 70 to 170 ° C in terms of improving physical properties by increasing adhesion between asphalt and aggregate.

The process oil contained in the polymer-modified neutralizing additive incorporating the cellulose fiber of the present invention is used as a processing aid, and aromatic process oil, paraffin process oil or a mixture thereof may be used.

Process oil is preferably included in the range of 5 to 40 parts by weight based on 100 parts by weight of styrene-butadiene-styrene block copolymer. When the amount of the process oil is less than 5 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene block copolymer, the flowability during processing is low, solubility in the asphalt is reduced, and when it exceeds 40 parts by weight, the viscosity of the asphalt mixture and Characteristics such as softening point may be lowered.

Polyethylene wax contained in the polymer-modified neutralizing additive incorporating the cellulose fiber of the present invention rapidly decreases the viscosity of the asphalt above the melting temperature of the wax, and solidifies below the melting temperature, thereby improving the performance of the medium-temperature asphalt mixture. It is used as an additive to make.

The polyethylene wax is preferably included in the range of 20 to 100 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene block copolymer. When the amount of the polyethylene wax is less than 20 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene block copolymer, the neutralizing effect on the asphalt mixture is hardly exerted, and when the amount of the polyethylene wax exceeds 100 parts by weight, the low temperature properties of the asphalt mixture are lowered. do.

It is preferable that polyethylene wax has melting | fusing point of 95-125 degreeC, and melt viscosity in 140 degreeC is 80-400 cPs.

If the melting point of the polyethylene wax is less than 95 ° C, the stiffness of the asphalt may be weakened when mixed with the asphalt. If the melting point is more than 125 ° C, the polyethylene wax may not be sufficiently dispersed in the asphalt during the manufacture of the medium-temperature asphalt mixture, which may cause deterioration of physical properties. .

In addition, when the melt viscosity of the polyethylene wax at 140 ° C. is less than 80 cPs, the high temperature property is weakened and is not suitable as road pavement asphalt. When the melt viscosity at 140 ° C. exceeds 400 cPs, the viscosity of the asphalt is too high to be moderate. In the manufacture and packaging of asphalt mixtures, problems may occur that are not properly performed.

The viscosity improving agent included in the polymer-modified neutralization additive incorporating the cellulose fiber of the present invention enhances the neutralization function of polyethylene wax, prevents the lowering of low-temperature physical properties of the asphalt, and increases the dispersion rate of the additive.

The viscosity improving agent is preferably included in the range of 5 to 50 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene block copolymer. When the amount of the viscosity improving agent is less than 5 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene block copolymer, the effect of improving the low temperature property and viscosity of the asphalt is insignificant, and when the amount of the viscosity improving agent exceeds 50 parts by weight, the high temperature property of the asphalt is lowered. Let's go.

The viscosity improving agent is preferably at least one selected from the group consisting of stearic acid, palm wax, palm oil, paraffin wax, polyolefin wax and fatty acid metal salts.

Palm wax is preferably a palm wax obtained through a hydrogenation process of the wax obtained from vegetable palm oil extracted from the palm fruit, the melting temperature is 55 ~ 65 ℃.

The paraffin wax has a melting temperature of 50 to 65 ° C and a melt viscosity at 100 ° C of 1 to 10 cst.

It is preferable that melting | fusing point of a polyolefin pin wax is 60-115 degreeC, and melt viscosity in 140 degreeC is 10-80 cPs.

The fatty acid metal salt is preferably at least one selected from the group consisting of calcium stearate, zinc stearate and magnesium stearate in terms of maximizing the low temperature property improvement and viscosity improving effect of the asphalt and preventing the high temperature property decrease.

Moreover, it is preferable that melting | fusing point of fatty acid metal salt is 120-150 degreeC.

The cellulose fiber included in the polymer-modified neutralizing additive incorporating the cellulose fiber of the present invention may serve to suppress the draindown phenomenon in which asphalt flows from the aggregate, thereby improving physical properties of the asphalt mixture.

The cellulose fiber is preferably included in an amount of 30 to 150 parts by weight based on 100 parts by weight of styrene-butadiene-styrene block copolymer. When the amount of cellulose fiber is less than 30 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene block copolymer, it is not possible to effectively suppress the draindown phenomenon of the asphalt, or the content of the additive required to obtain an equivalent effect is excessively increased. If it exceeds 150 parts by weight, it is difficult to expect the advantages of separately adding the cellulose fiber, it is difficult to mold the additive in the form of pellets, the viscosity is high, the problem of compaction and construction of the asphalt mixture occurs do.

Cellulose fibers may be cellulose short fibers having a length of 0.01 to 8 mm, a thickness of 7 to 80 μm, and a weight average length of 1.5 to 3 mm / g.

When the length of the cellulose short fibers is less than 0.01 mm, the entanglement of the fibers is considerably lowered, which makes it difficult to form the additive in pellet form. When the length of the cellulose shorter fibers is exceeded, the entanglement of the fibers becomes too large. Overloading may occur.

In addition, when the thickness of the cellulose short fibers exceeds 80 µm, the surface area of the short fibers decreases, resulting in poor asphalt absorption effect.

Cellulose short fibers can be produced by dry grinding and mechanical processing of natural pulp, recycled paper or waste paper by a hammer crusher or the like.

In addition, the polymer-modified neutralizing additive incorporating the cellulose fiber of the present invention may further include one or more selected from the group consisting of antioxidants, heat stabilizers, antistatic agents and lubricants.

On the other hand, according to another embodiment of the present invention, a method for preparing a polymer-modified neutralizing additive incorporating cellulose fiber is iii) styrene-butadiene-styrene block copolymer and 100 parts by weight of the styrene-butadiene-styrene block copolymer. Melt mixing 5 to 60 parts by weight of tackifying resin, 5 to 40 parts by weight of process oil, 20 to 100 parts by weight of polyethylene wax, 5 to 50 parts by weight of viscosity improving agent, and 30 to 150 parts by weight of cellulose fiber; And ii) molding the melt mixture formed in step iii).

Melt mixing of step iii) is preferably carried out at a temperature of 110 ~ 160 ℃.

Melt mixing can be accomplished using polymer melt mixing equipment known in the art, and for example, single or twin screw extruders, kneaders and Intensive Mixers can be used.

The molding step can be accomplished using common methods known in the art, for example by cooling and pressing the melt mixture and cutting it into pellets.

On the other hand, asphalt using a polymer-modified neutralizing additive incorporating cellulose fiber according to another embodiment of the present invention is iii) 3 to 20% by weight of a polymer-modifying neutralizing additive incorporating cellulose fiber according to the present invention; And ii) 80 to 97% by weight asphalt.

In the present invention, any asphalt generally used for road pavement may be used as the asphalt. Asphalt can generally be classified according to the penetration test results according to ASTM D946. Specifically, the invasion of asphalt intrudes the standard needle into the asphalt for a defined load and time at the reference temperature, thereby defining the penetration amount as the penetration of the asphalt. Penetration is a value that represents the hardness of asphalt at 25 ° C. When the needle is pressed for 5 seconds with a force of 100 g, the needle penetration depth is expressed in 0.1 mm increments. It means asphalt. Representative road pavement asphalt currently produced in Korea is rated to 85 ~ 100 (AP-3) and 60 ~ 70 (AP-5) penetration level.

Asphalt content in the asphalt using the polymer-modified neutralizing additive incorporating the cellulose fiber of the present invention is 80 to 97% by weight, and the content of the polymer-modifying neutralizing additive incorporating the cellulose fiber is 3 to 20% by weight. desirable. When the content of the polymer-modified neutralizing additive incorporating cellulose fiber is less than 3% by weight, the effect of improving drainage and neutralizing is insignificant, and when it exceeds 20% by weight, the viscosity becomes too high to obtain a neutralizing effect. Therefore, there may be a problem that the compaction is not made or the physical properties are deteriorated at the desired medium temperature packaging temperature.

On the other hand, according to another embodiment of the present invention, the method for producing an asphalt mixture using the polymer-modified neutralizing additive incorporating cellulose fiber is iii) preparing a polymer-modified neutralizing additive incorporating cellulose fiber according to the method of claim 14. step; And ii) melt mixing the neutralizing additive with asphalt and aggregate.

The weight ratio of the polymer-modified neutralizing additive incorporating asphalt and cellulose fiber is preferably in the range of 80:20 to 97: 3.

In addition, the weight ratio of asphalt and aggregate is preferably in the range of 3.5: 96.5 to 8.0: 92.0.

Melt-mixing the polymer-modified neutralizing additive incorporating cellulose fiber with asphalt and aggregate is preferably performed at a temperature of 130 to 150 ° C.

According to the present invention, by using the polymer-modified neutralizing additive incorporating cellulose fiber, the dispersibility to asphalt is improved, while effectively suppressing the drainage of asphalt, while minimizing the amount of fiber additives and the cost of additional input. Can be improved.

Furthermore, the preparation and compaction temperature of the asphalt mixture can be efficiently lowered without deteriorating physical properties, thereby minimizing the emission of harmful gases such as carbon dioxide, sulfur oxides, and nitrogen oxides.

Hereinafter, the present invention will be described in more detail by way of examples. However, the following examples are merely to illustrate the invention, the scope of the present invention is not limited to the following examples.

[Example]

(1) Experimental material

AP: Asphalt with an intrusion grade of 60 to 80 (infiltration degree 70).

SBS: linear styrene-butadiene-styrene block copolymer having a weight average molecular weight of 90,000 g / mol and a styrene content of 33% by weight.

SBS-H: Linear styrene-butadiene-styrene block copolymer having a weight average molecular weight of 180,000 g / mol and a styrene content of 33% by weight.

Tackifying resin: An aromatic hydrocarbon petroleum resin having a softening point of 110 ° C.

Process oil: Paraffinic oil having a kinematic viscosity of 100 cSt at 40 ° C.

Cellulose Fibers: Cellulose short fibers having a length of 0.01 to 8 mm, a thickness of 7 to 80 μm, and a weight average length of 3 mm / g.

PE wax: polyethylene wax with melting point of 114 c, 140 c at 200 cPs and specific gravity 0.93

Palm wax: Palm wax extracted and hydrogenated from a coconut having a melting point of 60 c and a viscosity of 140 c at 6 cPs.

VIATOP: Fiber additive for SMA and drainage and specialty asphalt concrete sold by Insung Industries.

(2) pellet production and evaluation

According to the components and composition ratios shown in Tables 1 and 2 below, each material was melt mixed at a temperature of 110 to 160 ° C., and molded into pellets to prepare an additive. In the pellet manufacturing process, it was determined that the product was passed in the form of pellets, and failed if not formed in the form of pellets.

Example 1 Example 2 Example 3 Example 4 SBS 100 100 100 100 Tackifying resin 30 30 30 30 Process oil 20 20 20 20 PE wax 50 50 50 70 Palm wax 20 20 40 20 Cellulose fiber 60 100 100 100 Pellet manufacturing pass pass pass pass

(The content of each component is expressed in parts by weight of each component relative to 100 parts by weight of SBS.)

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 SBS 100 - 100 100 SBS-H - 100 - - Tackifying resin 30 30 30 30 Process oil 20 20 20 20 PE wax 50 50 0 50 Palm wax 20 40 0 40 Cellulose fiber 0 100 100 200 Pellet manufacturing pass pass pass fail

(The content of each component is expressed in parts by weight of each component relative to 100 parts by weight of SBS or SBS-H.)

As shown in Tables 1 and 2, in Examples 1 to 4 and Comparative Examples 1 to 3, the additive was made in a pellet form, but in the case of Comparative Example 4 having a large amount of cellulose fiber, the additive was made in pellet form. I didn't lose.

(3) Dispersibility (Solubility) Evaluation

Among the additives prepared, the same pellets ranging in size from 2-3 mm were selected. After the asphalt having a penetration of 70 was heated to a temperature of 150 ° C., dispersibility was evaluated by melting the additive prepared above to 10 wt% and 15 wt%, and measuring the dissolution rate. The results are shown in Tables 3 and 4 below.

Additive content Example 1 Example 2 Example 3 Example 4 10 wt% 55 minutes 40 minutes 35 minutes 40 minutes 15 wt% 65 minutes 50 minutes 45 minutes 45 minutes

Additive content Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 10 wt% 90 minutes 85 minutes 65 minutes - 15 wt% 95 minutes 90 minutes 75 minutes -

As shown in Tables 3 and 4, the dissolution rates of Examples 1 to 4 were faster than Comparative Examples 1 to 3. Looking at the results of Examples 1 to 4, it can be seen that the higher the content of the cellulose fiber and the viscosity improver, the faster the dissolution rate.

On the other hand, in Comparative Example 1, which does not contain cellulose fiber, the dissolution rate was lower than that of Examples 1 to 4, which contained cellulose fiber, and especially in Comparative Example 2 using a styrene-butadiene-styrene block copolymer having a high molecular weight. The dissolution rate was very slow. Comparative Example 4 was not made into pellets so no dissolution rate was measured.

(4) asphalt mixture evaluation

In order to evaluate the asphalt mixture, the additive prepared above was melt mixed with asphalt and aggregate to prepare an asphalt mixture. The aggregate used 13 mm aggregate used for SMA pavement and the asphalt content was 6.3% of the asphalt mixture.

In order to confirm the neutralization effect, when using the additives obtained in Examples 1 and 2 and Comparative Examples 1 and 3, the mixture was prepared at 150 ° C., and then used at 180 ° C. when the additive obtained in Comparative Example 3 was used. The mixture was prepared and compared by compaction.

In order to confirm the draindown effect, VIATOP which is a commercially available fiber additive when using the additive of Comparative Example 1 was used together, and the amount was added so that the amount of cellulose fiber in Example 1 and Comparative Example 1 was the same.

Compaction performance evaluation of the asphalt mixture was measured porosity after compaction, draindown evaluation was evaluated by the KS F 2489 test method at the compaction temperature of each mixture.

Table 5 shows the composition and measured values of the asphalt mixture.

Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Mixture Preparation Temperature (℃) 150 150 150 150 180 AP (% by weight) 88 88 88 88 88 Additive (% by weight) 12 12 9.4 12 12 VIATOP (% by weight) - - 2.6 - - Porosity (%) 2.8 3.0 2.9 Not determined 2.9 Draindown test value (%) 0.20 0.22 0.28 - 0.26

In order to evaluate the fatigue crack resistance of the asphalt mixture, the Indirect Tensile Fatigue Test was performed according to the AASHTO TP9 test method to measure the N _f result. In addition, the strength characteristics were evaluated by performing an indirect tensile strength test by the KS F 2382 test method to evaluate the strength characteristics.

Table 6 shows fatigue crack resistance and tensile strength measurements.

Example 1 Example 2 Comparative Example 3 Mixture manufacturing temperature (℃) 150 150 180 Test temperature (℃) 25 25 25 Additive content (wt%) 12 12 12 Fatigue Crack Resistance Evaluation (N _f ) 25,002 26,313 20,448 Indirect tensile strength (N / ㎡) 1.2135 1.3412 1.1112

※ Indirect Tensile Fatigue Test: A method of evaluating the behavior of fatigue by measuring the fatigue resistance of asphalt mixtures. Here, N _f represents the number of loads until the specimen breaks and is used as an index for evaluating resistance to cracking.

As shown in Table 5, when preparing the asphalt mixture at 150 ℃ to confirm the neutralization effect, when compacting, Comparative Example 2 that does not contain polyethylene wax and viscosity improver was not compacted. On the other hand, in the case of Comparative Example 3, which was compacted after preparing the asphalt mixture at 180 ℃, it can be seen that the porosity after compaction is similar to Examples 1 and 2, which was compacted after preparing the mixture at 150 ℃ has a moderate temperature effect there was.

In addition, in order to confirm the effect of improving the draindown by adding cellulose fiber in the additive, comparing Example 1 and Comparative Example 1 in which VIATOP was added separately, even if cellulose fiber is included in the additive, even if cellulose fiber is not added separately It can be seen that there is a sufficient draindown effect.

In addition, as shown in Table 6, Examples 1 and 2 were superior to Comparative Example 3 in terms of fatigue crack resistance and indirect tensile strength. In particular, in the case of Example 2, despite the same amount of additives, the highest results were obtained in terms of resistance to fatigue cracking and indirect tensile strength. This means that the fatigue life of the packaging is increased by about 25% and the resistance to cracking is increased by about 15% compared to Comparative Example 3.

As described above, in the present invention, by using the polymer-modified neutralizing additive incorporating cellulose fiber, the dispersibility to asphalt is improved, while effectively suppressing the drain down phenomenon of asphalt, minimizing the amount of fiber additives and adding them separately. Cost problems can be improved. In addition, addition of the additives of the present invention may result in an increase of about 15% to about 25% of the lifetime of the package. In addition, the preparation and compaction temperature of the asphalt mixture can be efficiently lowered without deteriorating physical properties, thereby minimizing the emission of harmful gases such as carbon dioxide, sulfur oxides, and nitrogen oxides.

Claims (19)

V) linear or branched styrene-butadiene-styrene block copolymers having a weight average molecular weight of 50,000 to 130,000 g / mol;
Ii) 5 to 60 parts by weight of aromatic hydrocarbon petroleum resin, aliphatic hydrocarbon petroleum resin, dicyclopentadiene petroleum resin, polybutene, coumarone-indene resin based on 100 parts by weight of the styrene-butadiene-styrene block copolymer At least one tackifying resin selected from the group consisting of polyterpene resins, terpene phenol resins, rosin, rosin esters, and hydrogenated products thereof;
Iii) 5-40 parts by weight of process oil, based on 100 parts by weight of the styrene-butadiene-styrene block copolymer;
V) a polyethylene wax having a melting point of 95 to 125 ° C and a melt viscosity of 80 to 450 cPs at 140 ° C with respect to 100 parts by weight of the styrene-butadiene-styrene block copolymer;
Iii) 5 to 50 parts by weight of stearic acid, palm wax, palm oil, paraffin wax, polyolefin wax and fatty acid metal salts having a melting point in the range of 120 to 150 ° C based on 100 parts by weight of the styrene-butadiene-styrene block copolymer. At least one viscosity improving agent selected from; And
Iii) Cellulose having from 30 to 150 parts by weight, 0.01 to 8 mm in length, 7 to 80 μm in thickness, and 1.5 to 3 mm / g in weight average length, based on 100 parts by weight of the styrene-butadiene-styrene block copolymer Containing cellulose fibers that are short fibers
Polymeric modified mesophilic additives incorporating cellulose fiber.
The method of claim 1,
The styrene-butadiene-styrene block copolymer is characterized in that the styrene content of 10 to 50% by weight
Polymeric modified mesophilic additives incorporating cellulose fiber.
The method of claim 1,
The tackifying resin is an aromatic hydrocarbon petroleum resin having a softening point of 70 ~ 170 ℃
Polymeric modified mesophilic additives incorporating cellulose fiber.
The method of claim 1,
The process oil is characterized in that the aromatic process oil, paraffin process oil or mixtures thereof
Polymeric modified mesophilic additives incorporating cellulose fiber. The method of claim 1,
The polyolefin wax has a melting point of 60 ~ 115 ℃, characterized in that the melt viscosity at 140 ℃ 10 ~ 80 cPs
Polymeric modified mesophilic additives incorporating cellulose fiber.
The method of claim 1,
The fatty acid metal salt is at least one member selected from the group consisting of calcium stearate, zinc stearate and magnesium stearate
Polymeric modified mesophilic additives incorporating cellulose fiber.
The method of claim 1,
It further comprises one or more selected from the group consisting of antioxidants, heat stabilizers, antistatic agents and lubricants
Polymeric modified mesophilic additives incorporating cellulose fiber.
Iii) with respect to 100 parts by weight of a linear or branched styrene-butadiene-styrene block copolymer having a weight average molecular weight of 50,000 to 130,000 g / mol,
5 to 60 parts by weight of aromatic hydrocarbon petroleum resin, aliphatic hydrocarbon petroleum resin, dicyclopentadiene petroleum resin, polybutene, coumarone-indene resin, polyterpene resin, terpene phenol resin, rosin, rosin ester, and their One or more tackifying resins selected from the group consisting of hydrogenated materials,
5 to 40 parts by weight of process oil,
Polyethylene wax having a melting point of 95 to 125 ° C. and a melt viscosity of 80 to 450 cPs at 140 ° C.,
5 to 50 parts by weight of stearic acid, palm wax, palm oil, paraffin wax, polyolefin wax and at least one viscosity improving agent selected from the group consisting of fatty acid metal salts having a melting point in the range of 120 to 150 ° C, and
Melt mixing 30-150 parts by weight of cellulose fiber, the cellulose short fibers having a length of 0.01-8 mm, a thickness of 7-80 μm, and a weight average length of 1.5-3 mm / g; And
Ii) molding the melt mixture formed in step iii);
A method for producing a polymer-modified neutralizing additive incorporating cellulose fiber.
The method of claim 8,
The step iii) is made at a temperature of 110 ~ 160 ℃
A method for producing a polymer-modified neutralizing additive incorporating cellulose fiber.
Iii) 3 to 20% by weight of a polymer modified neutralizing additive incorporating the cellulose fiber according to any one of claims 1 to 7; And
Ii) 80 to 97% by weight asphalt;
Asphalt using polymer modified mesophilic additives incorporating cellulose fiber.
Iii) preparing a polymer modified neutralizing additive incorporating cellulose fiber according to the method of claim 8; And
Ii) melt mixing the neutralizing additive with asphalt and aggregate,
The weight ratio of the polymer-modified neutralizing additive incorporating the asphalt and the cellulose fiber is in the range of 80:20 to 97: 3.
A method for producing an asphalt mixture using a polymer modified mesophilic additive incorporating cellulose fiber.
The method of claim 11,
Step ii) is characterized in that at a temperature of 130 ~ 150 ℃
A method for producing an asphalt mixture using a polymer modified mesophilic additive incorporating cellulose fiber.
The method of claim 11,
The weight ratio of the asphalt and the aggregate is characterized in that the range of 3.5: 96.5 to 8.0: 92.0
A method for producing an asphalt mixture using a polymer modified mesophilic additive incorporating cellulose fiber. delete delete delete delete delete delete