KR101282173B1 - Warm-mix dry type asphalt modifier comprising polyetylene non-woven fabrics dispersed therein and manafacturing method thereof - Google Patents

Abstract

PURPOSE: A medium temperature type dry asphalt modifier is provided to improve dissolution velocity of a modifier about asphalt by containing polyethylene felts dispersed in a state not dissolved in the modifier. CONSTITUTION: A medium temperature type dry asphalt modifier comprises i) styrene-butadiene-styrene block copolymer 100.0; ii) 5-60 parts by weight of resin which gives an adhesion property; iii) 20-80 parts by weight of process oil; iv)10-40 parts by weight of medium temperature additives; and v) 5-35 parts by weight of polyethylene felts. The adhesion property assigning resin is one or more selected from a group composed of aromatic hydrocarbon system petroleum resin, aliphatic hydrocarbon system petroleum resin, dycylopentadien system group petroleum resin, polybutene, coumarone-indene resin, polyterpene resin, terpene phenol resin, rosin, rosin ester and their hydrogen additives. The medium temperature additive is one or more selected from a group of polyethylene wax, vegetable wax, ranimal wax, surfactant and fatty acid. The polyethylene felt is dispersed in a non-melted state within the styrene-butadiene-styrene block copolymer, the adhesion property assigning resin, and the process oil. [Reference numerals] (AA) Comparative example 5; (BB) Example 1

Description

Medium-temperature dry asphalt modifier in which polyethylene non-woven fabric is dispersed, and method for manufacturing the same

The present invention relates to a mesophilic dry asphalt modifier, and more particularly, when preparing a mesophilic modified asphalt mixture by a dry method, it is possible to improve the dissolution rate of the modifier so that asphalt concrete having a high common grade is lower than that of the conventional pavement technology. The present invention relates to a mesophilic dry asphalt modifier in which a polyethylene nonwoven fabric which can be produced at a temperature is dispersed in an unmelted state, and a method of manufacturing the same.

Asphalt is black at room temperature and has a very solid semi-solid viscosity. It is classified into several grades based on its rigidity. Asphalt is tested using the asphalt penetration test result of ASTM D946 and PG grade of ASTM D6373. 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. Examples of the modifier used in the modified asphalt include additives such as styrene-butadiene-styrene block copolymers, polyolefin resins or styrene-butadiene rubbers. Of these, styrene-butadiene-styrene block copolymers are most widely used.

Modified asphalt is classified according to asphalt performance grade (PG) specification, and specifically, it is classified by five performances such as aging, plastic deformation, fatigue cracking and low temperature cracking using equipment such as DSR and BBR. Can be. Asphalt compatibility grade is expressed as PG ○○-○○, for example, PG 76-22 has a physical property that can maintain the durability and bearing capacity as asphalt up to at least 76 ℃, up to -22 ℃ as a binder for road pavement It indicates the durability against low temperature. Therefore, modified asphalt is classified as high performance modified asphalt as the asphalt's common grade is higher.

In general, the higher the molecular weight of the styrene-butadiene-styrene block copolymer, the higher the molecular weight, the higher the softening point, the viscosity and the common grade of asphalt when dissolved in asphalt, but the more time required to dissolve in asphalt there is a problem.

The method of manufacturing modified asphalt for road is a wet type in which a pellet or crumb-type modifier is melted at high temperature in a large melting facility and melted at a high temperature, and then transferred to an asphalt concrete plant and mixed with aggregate and asphalt, and aggregate in an asphalt concrete plant. When mixing asphalt with a modifier may be divided into a 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 is not suitable for the operation of the process, and phase separation phenomenon occurs in which the modifier and the asphalt are separated during storage or transportation. 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 dry type, it is important to allow the modifier to dissolve in asphalt in a short time. If the melting time is late, a problem arises in that the working time is delayed in the production of the asphalt mixture, or the modifier is not sufficiently melted, so that it cannot exhibit sufficient performance as the modified asphalt.

In order to solve this problem, dry asphalt modifier composition using a styrene-butadiene-styrene block copolymer mixed with a tackifying resin and a processing aid is known, but these dry modifiers are also used to improve the common grade of asphalt When using a high viscosity styrene-butadiene-styrene block copolymer there is a limit to the melt rate.

On the other hand, after the asphalt concrete is manufactured through a high temperature heating process of 160 ~ 200 ℃, the process of cooling to room temperature in the installation and compaction process on the road. Therefore, when the asphalt mixture is manufactured, a lot of energy is consumed for the high temperature heating process, and there is a problem in that harmful gas emissions such as carbon dioxide (CO ₂ ) are increased even during the manufacture and construction of the asphalt mixture. In addition, when paving the road, there is a problem that workers are exposed to the risk of safety accidents along with the problem that the traffic opening time is delayed by the time required to cool the asphalt mixture to a temperature close to room temperature.

Recently, to solve these problems, researches are being actively conducted to reduce carbon dioxide emissions due to the asphalt mixture pavement by lowering the mixing and compaction temperature of the asphalt and aggregate without deteriorating the physical properties of the asphalt mixture. According to this road paving technology, it is possible to prepare an asphalt mixture at a temperature of 20 ~ 40 ℃ low compared to the conventional road paving technology. This road pavement technology is called a medium temperature pavement technology. Due to the advantages of lowering the construction temperature, introduction of a medium temperature pavement technology is required in the development of a modifier in the asphalt road field.

Therefore, when the modified asphalt mixture using the asphalt modifier is manufactured by the dry method, it is possible to improve the dissolution rate of the asphalt modifier and to dissolve it evenly in a short time, and to obtain a higher common grade when using the same amount of the dry modifier. Furthermore, there is a need for the development of dry asphalt modifiers with mesophilic pavement technology to minimize the release of harmful gases by producing asphalt concrete at lower temperatures than conventional pavement techniques.

When the modified asphalt mixture is prepared by the dry method, the polyethylene nonwoven fabric dispersed in the asphalt modifier is melted to improve the dissolution rate of the asphalt modifier, and the asphalt concrete having a high common grade at a lower temperature than the conventional pavement technology is used. It is an object of the present invention to provide a mesophilic dry asphalt modifier in which a polyethylene nonwoven fabric capable of reducing emissions of harmful gases such as carbon dioxide is dispersed in an unmelted state, and a manufacturing method thereof.

The mesophilic dry asphalt modifier of the present invention for solving the above problems is based on: i) 100 parts by weight of styrene-butadiene-styrene block copolymer, ii) aromatic hydrocarbon petroleum resin, aliphatic hydrocarbon petroleum resin, dicyclopentadiene system. 5 to 60 parts by weight of one or more tackifying resins selected from the group consisting of petroleum resins, polybutenes, coumarone-indene resins, polyterpene resins, terpene phenol resins, rosin, rosin esters, and hydrogenated products thereof, i) 20 to 80 parts by weight of process oil, i) 10 to 40 parts by weight of at least one neutralizing additive selected from the group consisting of polyethylene wax, vegetable wax, animal wax, surfactant and fatty acid; And iii) 5 to 35 parts by weight of a polyethylene nonwoven fabric, wherein iii) the polyethylene nonwoven fabric comprises iii) styrene-butadiene-styrene block copolymer, ii) tackifying resin, iii) process oil, and iii) neutralization And dispersed in a molten state in the molten mixture of the additive.

In addition, the method for producing a mesophilic dry asphalt modifier of the present invention comprises: i) aromatic hydrocarbon petroleum resin, aliphatic hydrocarbon petroleum resin, dicyclopentadiene petroleum resin, based on 100 parts by weight of styrene-butadiene-styrene block copolymer, 5 to 60 parts by weight of at least one tackifying resin selected from the group consisting of polybutene, coumarone-indene resin, polyterpene resin, terpene phenol resin, rosin, rosin ester, and hydrogenated products thereof, process oil 20 to 80 Melt blending parts by weight and 10 to 40 parts by weight of one or more neutralizing additives selected from the group consisting of polyethylene waxes, vegetable waxes, animal waxes, surfactants and fatty acids; And ii) dispersing 5 to 35 parts by weight of the polyethylene nonwoven fabric in the molten state with respect to 100 parts by weight of the styrene-butadiene-styrene block copolymer in the molten mixture of iii).

The mesophilic dry asphalt modifier according to the present invention maintains the polyethylene nonwoven fabric in a dispersed form without melting in the modifier, and when the asphalt concrete is manufactured by the dry method in the plant, the polyethylene nonwoven fabric which is present in the dispersed form in the modifier is present. While melting, it is possible to improve the dissolution rate of the modifier.

In addition, according to the mesophilic dry asphalt modifier of the present invention, it is possible to obtain asphalt concrete having a high common grade by the polyethylene nonwoven fabric melted in the asphalt concrete manufacturing step.

In addition, according to the mesophilic dry asphalt modifier of the present invention, it is possible to manufacture asphalt concrete at a lower temperature than the conventional pavement technology, it is possible to minimize the emission of harmful gases such as carbon dioxide.

1 is a specimen photograph of 0.2 mm thick formed by pressing the modifiers of Example 1 and Comparative Example 5 at 110 ° C., respectively.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

One embodiment of the present invention is iii) 100 parts by weight of styrene-butadiene-styrene block copolymer, ii) aromatic hydrocarbon petroleum resin, aliphatic hydrocarbon petroleum resin, dicyclopentadiene petroleum resin, polybutene, coumarone 5 to 60 parts by weight of at least one tackifying resin selected from the group consisting of indene resins, polyterpene resins, terpene phenol resins, rosin, rosin esters, and hydrogenated products thereof, i) 20 to 80 parts by weight of process oil, Iii) 10 to 40 parts by weight of one or more neutralizing additives selected from the group consisting of polyethylene waxes, vegetable waxes, animal waxes, surfactants and fatty acids; And iii) 5 to 35 parts by weight of a polyethylene nonwoven fabric, wherein iii) the polyethylene nonwoven fabric comprises iii) styrene-butadiene-styrene block copolymer, ii) tackifying resin, iii) process oil, and iii) neutralization A mesophilic dry asphalt modifier, characterized in that it is dispersed in a molten state in a molten mixture of additives.

The styrene-butadiene-styrene block copolymer included in the mesophilic dry asphalt modifier according to an embodiment of the present invention is used as an asphalt modifier to improve the physical properties of the asphalt according to temperature.

The styrene-butadiene-styrene block copolymer may be used without particular limitation as long as it is generally used in the art, but specifically, the styrene content is 25 to 40% by weight, and the weight average molecular weight is in the range of 80,000 to 150,000 g / mol. Phosphorus linear or branched copolymers can be used.

If the styrene content of the styrene-butadiene-styrene block copolymer is less than 25% by weight, the elasticity is insufficient, so that physical properties such as softening point may be lowered when the asphalt is modified.In the case of more than 40% by weight, the plastic properties become stronger due to the asphalt modification effect. There is not a big problem.

In addition, when the weight average molecular weight of the styrene-butadiene-styrene block copolymer is less than 80,000 g / mol, the asphalt modification effect may not be large. If the weight-average molecular weight exceeds 150,000 g / mol, the viscosity and the phase transition temperature may be too high, thereby modifying the asphalt as a modifier. There is a difficulty in melting, the pellet processing temperature is too high during the manufacture of the modifier to melt the polyethylene non-woven fabric during the process is difficult to disperse the modifier during asphalt concrete manufacturing.

Tackifying resin included in the mesophilic dry asphalt modifier according to an embodiment 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 the asphalt mixture is prepared.

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.

Process oil included in the mesophilic dry asphalt modifier according to an embodiment of the present invention is used as a processing aid, aromatic process oil, paraffin process oil or a mixture thereof may be used.

In order to improve the viscosity of asphalt, it is preferable to use paraffin-based process oil having an aromatic content of 0 to 30% by weight, naphthenic content of 20 to 50 parts by weight, and paraffin content of 40 to 80% by weight. no.

Process oil is preferably included in the range of 20 to 80 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 20 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene block copolymer, the flowability during processing is low and the solubility in asphalt is reduced. Since the nonwoven fabric is melted, there is a problem that it is difficult to melt the modifier during asphalt concrete production. On the other hand, when the amount of the process oil exceeds 80 parts by weight with respect to 100 parts by weight of the styrene-butadiene-styrene block copolymer, the physical properties of the modified asphalt composition have no significant effect, but after the preparation of the modifier, the process oil in the modifier elutes to the surface of the modifier. This will cause difficulties in handling.

The mesophilic additive included in the mesophilic dry asphalt modifier according to an embodiment of the present invention rapidly drops the viscosity of the asphalt above the melting temperature and solidifies below the melting temperature, thereby improving the performance of the mesophilic asphalt mixture. It is used as an additive for.

The neutralizing additive is preferably included in the range of 10 to 40 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene block copolymer. If the amount of the neutralizing additive is less than 10 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 it exceeds 40 parts by weight, the low temperature properties of the asphalt mixture Degrades.

The neutralizing additive is preferably at least one member selected from the group consisting of polyethylene wax, vegetable wax, animal wax, surfactant and fatty acid.

Moreover, it is preferable that melting | fusing point of the neutralizing additive is 120 degrees C or less, and melt viscosity in 140 degreeC is 200 cPs or less. If the melting point of the neutralizing additive is higher than 120 ° C., it will not be melted in the modifier manufacturing process, resulting in a problem that the viscosity of the modifier rises. In addition, when the melt viscosity of the neutralizing additive at 140 ° C. exceeds 200 cPs, the viscosity becomes higher than that of asphalt, which may affect the neutralizing effect.

Polyethylene nonwoven fabric included in the mesophilic dry asphalt modifier according to an embodiment of the present invention is present in a dispersed form without melting in the prepared modifier, but melted in the asphalt concrete manufacturing step to improve the dissolution rate of the modifier, polyethylene It is possible to produce asphalt concrete of high compatibility grade.

The polyethylene nonwoven fabric is preferably included in the range of 5 to 35 parts by weight based on 100 parts by weight of styrene-butadiene-styrene block copolymer. When the amount of the polyethylene nonwoven fabric is less than 5 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene block copolymer, the melt rate of the modifier may be lowered when the modifier is melted on the asphalt. Due to poor properties, in the process of molding the modifier into pellets, an excessive load may be applied to the equipment and the low temperature properties of the modifier may be affected.

Polyethylene nonwovens can be made using polyethylene fibers.

The polyethylene fiber used for producing the polyethylene nonwoven fabric is a fiber made using a polyethylene resin, but its kind is not particularly limited, but the thickness of the fiber is preferably about 7 to 200 μm.

If the thickness of the fiber is less than 7 ㎛ may cause a problem in dispersion due to the weak rigidity, if it exceeds 200 ㎛ may give an excessive load to the melt mixing equipment during the manufacture of the modifier, there is a fear that the difficulty in producing the modifier. .

It is preferable that melt temperature of polyethylene fiber is 126-140 degreeC. If the melt temperature of the polyethylene fiber is less than 126 ° C, since the nonwoven fabric made of polyethylene fiber cannot be melted and present in the form of dispersion in the modifier at the time of preparation of the modifier, the dissolution rate of the modifier is affected during asphalt concrete production. On the other hand, when the melting temperature exceeds 140 ℃ it is difficult to melt the modifier on the asphalt when manufacturing asphalt concrete.

In addition, it is preferable that the melt flow index of polyethylene fiber is 10 g / 10min or more. If the melt flow index of the polyethylene fiber is lower than 10g / 10min, the viscosity of the asphalt is raised, there is a difficulty in showing the neutralizing effect when asphalt paving.

Processes for preparing nonwoven fabrics from polyethylene fibers are well known in the art, and for example, polyethylene fibers may be manufactured in the form of fabrics by binding fiber aggregates through mechanical, chemical or thermal treatments, but are not limited thereto. .

As such, the use of polyethylene nonwovens allows for more uniform and easily dispersing in the modifiers during the preparation of the modifiers compared to the fibers themselves.

Polyethylene nonwovens may not be particularly limited in size or shape depending on the modifier manufacturing equipment, or the size may be limited to a range, for example about 3 cm or less.

In one embodiment, the mesophilic dry asphalt modifier according to the aspect may further comprise one or more selected from the group consisting of antioxidants, heat stabilizers, antistatic agents and lubricants.

In one embodiment, the mesophilic dry asphalt modifier according to the aspect may be in the form of pellets.

According to another embodiment of the present invention, i) aromatic hydrocarbon-based petroleum resin, aliphatic hydrocarbon-based petroleum resin, dicyclopentadiene-based petroleum resin, polybutene, and coumarone- based on 100 parts by weight of styrene-butadiene-styrene block copolymer 5 to 60 parts by weight of one or more tackifying resins selected from the group consisting of indene resins, polyterpene resins, terpene phenol resins, rosin, rosin esters, and hydrogenated additives thereof, 20 to 80 parts by weight of process oil, and polyethylene wax Melt mixing 10 to 40 parts by weight of one or more neutralizing additives selected from the group consisting of vegetable waxes, animal waxes, surfactants and fatty acids; And ii) dispersing 5 to 35 parts by weight of polyethylene nonwoven in an unmelted state relative to 100 parts by weight of the styrene-butadiene-styrene block copolymer in the molten mixture of iii). It relates to a manufacturing method.

The melt-kneading apparatus and conditions used for melt mixing of i) can use well-known polymer melt mixing equipment and conditions, as long as it does not deviate from the objective of this invention.

Such examples include single screw or twin screw extruders, kneader or balm mixers, and the like. When using a single screw or twin screw extruder, the polyethylene nonwoven fabric should be cut to an appropriate size, for example, about 3 cm or less for ease of feeding, and the size and shape of the polyethylene nonwoven fabric are not limited when using a kneader or balm mixer. .

The melt mixing of iii) and the dispersion of ii) are in terms of the temperature range in which the styrene-butadiene-styrene block copolymers, tackifying resins, process oils and neutralizing additives are melted while the polyethylene nonwoven is not melted and dispersed. It is preferable to make it at the temperature of 110-125 degreeC.

If the temperature at which the melt mixing of i) and the dispersion of ii) is less than 110 ° C. is too low, the melt mixing becomes difficult, and the viscosity of the modifier is high, making processing difficult. If the temperature exceeds 125 ° C., the polyethylene nonwoven fabric may not be melted and dispersed in the modifier during manufacture of the modifier, thereby affecting the melting rate of the modifier during asphalt concrete production.

In one embodiment, after step ii), it may further comprise the step of cooling the mixture, and molding the cooled mixture in the form of pellets.

In one embodiment, in the step iii), it may further comprise mixing at least one additive selected from the group consisting of antioxidants, heat stabilizers, antistatic agents and lubricants.

In the method for producing a mesophilic dry asphalt modifier, a styrene-butadiene-styrene block copolymer, a tackifying resin, a process oil, and a neutralizing additive are melt mixed and the polyethylene nonwoven fabric is dispersed in the melt mixture.

However, in the method for producing a mesophilic dry asphalt modifier according to another embodiment of the present invention, styrene-butadiene-styrene block copolymer, tackifying resin, process oil, neutralizing additive and polyethylene nonwoven fabric, styrene-butadiene The styrene block copolymers, tackifying resins, process oils and neutralizing additives are melted, while the polyethylene nonwovens may be mixed together at temperatures that do not melt. Mixing at such temperature conditions can produce a mesophilic dry asphalt modifier in which a polyethylene nonwoven is dispersed in a molten mixture of styrene-butadiene-styrene block copolymers, tackifying resins, process oils and neutralizing additives.

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

[ Example ]

1. Experimental material

AP 5: Asphalt Grade 60 to 80 with Asphalt Grade 70 (PG 64-22)

SBS 1: Linear styrene-butadiene-styrene block copolymer having a weight average molecular weight of 100, OO g / mol and a styrene content of 33% by weight

SBS 2: Linear styrene-butadiene-styrene block copolymer having a weight average molecular weight of 180, OOO g / mol and a styrene content of 33% by weight

Tackifying Resin: Aromatic Hydrocarbon Petroleum Resin with Softening Point of 110 ℃

Process oil: paraffinic oil with 40 ° C kinematic viscosity of 100 cSt

Medium temperature additive: "LEADCAP 64" (Leadcap Co., Ltd.) with melting temperature of 140 ° C, 150 cps and melting point of 110 ° C

PE nonwoven fabric 1: Polyethylene nonwoven fabric having a thickness of 0.5 mm made of polyethylene fiber having a thickness of 100 μm made of polyethylene resin having a melting temperature of 130 ° C. and a melt flow index of 15 g / 10 min.

PE nonwoven fabric 2: Polyethylene nonwoven fabric having a thickness of 0.5 mm made of polyethylene fiber having a thickness of 100 μm made of polyethylene resin having a melting temperature of 130 ° C. and a melt flow index of 5 g / 10 min.

PE pellets: pellet-shaped polyethylene with a diameter of 0.5 to 1.0 mm made of polyethylene resin having a melting temperature of 130 ° C. and a melt flow index of 15 g / 10 min.

2. Experimental Method

(1) For the evaluation of solubility in asphalt, which is the most important item in dry asphalt modifier, the dissolution time of the modifier in asphalt was measured by referring to the "Sampling Method of Modified Asphalt" described in the Pavement Test Manual established by the Japan Road Association. And the results are shown in Tables 3 and 4. Asphalt used was AP 5, and 8 wt% of the modifier was added to the asphalt at 150 ° C., and the mixture was mixed at 3,000 rpm to evaluate the time when the modifier was completely dissolved.

(2) Evaluation of the physical properties of each asphalt (AP 5) including the modifier was based on the PG test. To determine the PG grade, the low and high temperature properties are measured. First, in order to evaluate the low temperature properties, the asphalt was measured by PAV (Pressure Aging Vessel), and then mvalue value by BBR (Bending Beam Rheometer). The low temperature grade of PG was determined by the temperature at which the m-value value was greater than 0.3 in the BBR test at -12 ° C. In order to evaluate the high temperature properties, asphalt mixed with aggregate at high temperatures in the initial plant during the production of ascon, and then subjected to the Rolling Thin Film Oven Test (RTFO), which simulates the aging of the process of moving and laying the site, is subjected to DSR (Dynamic). Shear Rheometer) was used to measure G * / sinδ at 64 ° C., 70 ° C., 76 ° C. and 82 ° C., and the temperature at which the G * / sin δ value was 2.2 kPa or more was determined as the high temperature grade of PG. At this time, the higher the G * / sin δ at the same temperature has a higher temperature stability.

(3) To 100 parts by weight of asphalt (AP) heated to 150 ℃ to evaluate the compaction performance of the asphalt mixture, 6% by weight of the medium-temperature dry asphalt modifier prepared in the composition ratios of Examples and Comparative Examples was added, followed by mixing Modified asphalt was prepared. 6% by weight of the modified asphalt prepared was added to the aggregate heated to the same temperature as the asphalt temperature, and mixed to prepare asphalt concrete.

3. Modifier  Of asphalt and modified asphalt

(1) Example 1

100 parts by weight of a linear styrene-butadiene-styrene block copolymer having a weight average molecular weight of 100,000 g / mol and a styrene content of 33% by weight, 30 parts by weight of tackifying resin, 40 parts by weight of process oil, 20 parts by weight of a neutralizing additive, and 10 parts by weight of the polyethylene nonwoven fabric was placed in a Bambari mixer and mixed for 20 minutes at a temperature of 115 ° C., which is an optimum temperature at which components other than the polyethylene nonwoven fabric are melted. Alternatively, 100 parts by weight of a linear styrene-butadiene-styrene block copolymer having a weight average molecular weight of 100,000 g / mol and a styrene content of 33% by weight, 30 parts by weight of tackifying resin, 40 parts by weight of process oil, and 20 parts of neutralizing additive The part was put into a balvarie mixer and mixed at a temperature of 115 ° C. for 20 minutes, and then 10 parts by weight of polyethylene nonwoven fabric was added and further mixed. The mixed mixture was passed through an extruder having a L / D of 6 at 115 ° C., the same temperature as that of the balvarie mixer, and a pellet modifier having a diameter of about 2 to 3 mm was prepared using an under water cutter.

6% by weight of the asphalt modifier prepared above was added to asphalt (AP5) having a penetration rate (25 ° C., 100 g, 5 seconds, 0.1 mm) of 70 ° C., a softening point of 50 ° C., and PG 64-22. And melt-mixing at 3,000 rpm to produce a modified asphalt. In this case, the time at which the modifier is dissolved and the PG grade determination result of the modified asphalt are shown in Table 3 below.

(2) Example  2 to 6

In the same manner as in Example 1, a modifier was prepared according to the composition ratios shown in Table 1. The processing temperature at the time of preparation of the modifier was the optimum temperature at which components other than the polyethylene nonwoven fabric were melted.

6% by weight of the asphalt modifier prepared above was introduced into asphalt (AP5) having a penetration rate (25 ° C., 100 g, 5 seconds, 0.1 mm), melted at 150 ° C., 70, and a softening point of 50 ° C., at 3,000 rpm. Melt mixing to produce modified asphalt. In this case, the time at which the modifier is dissolved and the PG grade determination result of the modified asphalt are shown in Table 3.

(3) Comparative example  1 to 6

In the same manner as in Example 1, a modifier was prepared according to the composition ratios shown in Table 1. In Comparative Examples 1 to 4 and 6, the processing temperature at the time of preparation of the modifier was an optimum temperature at which the remaining components except the polyethylene of a nonwoven polyethylene or pellets were melted. Comparative Example 5 was carried out by artificially adjusting the processing temperature to 170 ℃ to completely melt the polyethylene nonwoven fabric.

6% by weight of the asphalt modifier prepared above was introduced into asphalt (AP5) having a penetration rate (25 ° C., 100 g, 5 seconds, 0.1 mm), melted at 150 ° C., 70, and a softening point of 50 ° C., at 3,000 rpm. Melt mixing to produce modified asphalt. In this case, the time at which the modifier is dissolved and the PG grade determination result of the modified asphalt are shown in Table 4.

(4) manufacture of asphalt mixture

8 weight% of the mesophilic dry asphalt modifier prepared at the composition ratios of Examples 1, 5, and Comparative Examples 2, 6 was added to 100 parts by weight of asphalt (AP) heated to 150 ° C, and melt-mixed to prepare modified asphalt. . 6% by weight of the modified asphalt was added to the aggregate heated to the same temperature as the asphalt temperature, and mixed to prepare asphalt concrete. The porosity of the manufactured asphalt concrete was measured, and the neutralizing effect was evaluated. The porosity measurement results are shown in Table 5.

division
Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Optimum mixing temperature 115 ℃ 117 ℃ 125 ℃ 114 ° C 123 ℃ 120 DEG C Modifier
Composition SBS 1 100 100 100 100 100 100 Tackifying Resin (phr) 30 30 30 30 30 30 Process oil
(phr) 40 40 40 40 40 60 Mesophilic additive (phr) 20 20 20 35 35 35 PE nonwoven fabric 1 (phr) 10 20 30 10 30 30

division
Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Optimum mixing temperature 113 ℃ 115 ℃ 115 ℃ 135 ℃ 160 ° C 135 ℃ Modifier
Composition SBS 1 100 100 100 100 100 SBS 2 100 Tackifying Resin (phr) 30 30 30 30 30 30 Process oil
(phr) 40 40 40 40 40 40 Mesophilic additive (phr) 20 20 20 20 20 20 PE nonwoven fabric 1 (phr) 0 10 10 40 PE nonwoven fabric 2 (phr) 10 PE pellets (phr) 10

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Dissolution time (min) 45min 35min 25min 40min 20min 18min PG rating PG 70-22 PG 70-22 PG 76-22 PG 70-22 PG 76-22 PG 76-22 RTFO DSR
G * / sinδ (KPa) 70 ℃ 2.5 2.9 3.4 2.2 3.8 3.6 76 ℃ 1.3 1.7 2.2 1.2 2.3 2.2

* PG rating of AP5 is PG 64-22

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Dissolution time (min) 85 min 47min 80min 90min 75 min 65 min PG rating PG 64-22 PG 70-22 PG 70-22 PG 76-22 PG 70-22 PG 76-18 RTFO DSR
G * / sinδ (KPa) 70 ℃ 2.1 2.6 2.4 3.6 2.6 4.0 76 ℃ 1.1 1.4 1.3 2.2 1.4 2.5

* PG rating of AP5 is PG 64-22

* Comparative Example 6 is not good pellet state due to heavy equipment load

Example 1 Example 5 Comparative Example 2 Comparative Example 6 Asphalt Concrete Manufacturing Temperature (℃) 150 ℃ 150 ℃ 150 ℃ 150 ℃ Porosity (%) 3.9 4.0 4.3 4.8

1 is a specimen photograph of 0.2 mm thickness formed by pressing the modifiers of Example 1 and Comparative Example 5 at 110 ° C., respectively, showing the state of the polyethylene nonwoven fabric present in the modifier. In the case of Example 1, the polyethylene nonwoven fabric was dispersed without melting to show an opaque state, whereas in Comparative Example 6, the polyethylene nonwoven fabric was melted and semitransparent.

From Tables 3 and 4, in the case of the embodiment using the modifier in which the polyethylene nonwoven fabric according to the present invention is dispersed, Comparative Examples 1 and 2 using the modifier in which the polyethylene dissolving agent is not dissolved in asphalt during the manufacture of asphalt concrete It can be seen that the increase compared to.

Specifically, in Examples 1 to 3, the dissolution rate of the modifier was greatly increased during asphalt concrete production according to the presence or absence of the polyethylene nonwoven fabric when compared with Comparative Example 1 without the polyethylene nonwoven fabric. In addition, in Examples 1 to 3, it was confirmed that as the amount of polyethylene nonwoven fabric included in the modifier increases, the dissolution rate of the modifier increases during asphalt concrete production.

In addition, the composition ratio is the same, but the processing temperature is low, compared to Example 1 in which the polyethylene nonwoven fabric is not melted and dispersed in the modifier, compared to Comparative Example 5 in which the polyethylene nonwoven fabric is melted in the modifier by artificially increasing the processing temperature. As is present in the dispersed state without melting, it can be seen that significantly increases the dissolution rate of the modifier during asphalt concrete production.

In addition, it can be seen from Example 1 and Comparative Example 3 that there is a difference in the dissolution rate of the modifier during asphalt concrete production according to the polyethylene shape distributed in the modifier. Example 1 and Comparative Example 4 show that the molecular weight of the styrene-butadiene-styrene block copolymer also affects the processing temperature, so that there is a difference in dissolution rate of the modifier during asphalt concrete production.

In addition, it can be seen through Examples 1 to 3 and Comparative Example 1 that the polyethylene nonwoven fabric dispersed in the modifier improves the dissolution rate of the modifier during asphalt concrete production, and the asphalt concrete produced may have a high common grade. In the case of Comparative Example 6 in which an excessive amount of polyethylene nonwoven fabric is added, it can be seen that although the dissolution rate of the modifier is excellent during asphalt concrete production, low temperature physical properties are not good.

On the other hand, from the porosity measurement results shown in Table 5, although the modifiers of Examples 1 and 5 are capable of mesophilic packaging, Comparative Example 2 using a nonwoven fabric made of polyethylene fiber with a high viscosity and Comparative Example 6 containing an excessive amount of polyethylene nonwoven fabric In this case, it can be seen that the compaction performance is poor and does not exhibit a neutralizing effect.

It is to be noted that the technical spirit of the present invention has been specifically described in accordance with the above-described preferred embodiments, but it is to be understood that the above-described embodiments are intended to be illustrative and not restrictive. In addition, those skilled in the art will understand that various embodiments are possible within the scope of the technical idea of the present invention.

Claims (16)

Iii) 100 parts by weight of styrene-butadiene-styrene block copolymer,
Ii) aromatic hydrocarbon petroleum resin, aliphatic hydrocarbon petroleum resin, dicyclopentadiene petroleum resin, polybutene, coumarone-indene resin, polyterpene resin, terpene phenol resin, rosin, rosin ester, and hydrogenated additives thereof 5 to 60 parts by weight of one or more tackifying resins selected from the group consisting of,
V) 20 to 80 parts by weight of process oil,
Iii) 10 to 40 parts by weight of one or more neutralizing additives selected from the group consisting of polyethylene waxes, vegetable waxes, animal waxes, surfactants and fatty acids; And
Iii) 5 to 35 parts by weight of polyethylene nonwoven fabric,
(Iii) the polyethylene nonwoven fabric is dispersed in a molten mixture of (iii) styrene-butadiene-styrene block copolymer, (ii) tackifying resin, (iii) process oil, and (iii) neutralizing additive. Characterized by
Medium temperature dry asphalt modifier.
The method of claim 1,
Iii) the styrene-butadiene-styrene block copolymer is a linear or branched copolymer having a styrene content of 25 to 40% by weight and a weight average molecular weight in the range of 80,000 to 150,000 g / mol.
Medium temperature dry asphalt modifier.
The method of claim 1,
Said ii) tackifying resin is an aromatic hydrocarbon petroleum resin having a softening point of 70 ~ 170 ℃
Medium temperature dry asphalt modifier.
The method of claim 1,
Iii) the process oil is selected from the group consisting of aromatic process oils, paraffinic process oils and mixtures thereof.
Medium temperature dry asphalt modifier.
The method of claim 1,
Iii) the polyethylene nonwoven fabric is produced using polyethylene fibers,
Medium temperature dry asphalt modifier.
The method of claim 5,
The polyethylene fiber has a melting temperature of 126 ~ 140 ℃, characterized in that the melt flow index is 10g / 10min or more
Medium temperature dry asphalt modifier.
The method of claim 1,
(Iii) the polyethylene nonwoven fabric has a thickness in the range of 0.1 to 10 mm.
Medium temperature dry asphalt modifier.
The method of claim 1,
The mesophilic dry asphalt modifier is characterized in that the pellet form
Medium temperature dry asphalt modifier.
The method of claim 1,
It further comprises one or more additives selected from the group consisting of antioxidants, heat stabilizers, antistatic agents and lubricants
Medium temperature dry asphalt modifier.
Iii) Aromatic hydrocarbon petroleum resin, aliphatic hydrocarbon petroleum resin, dicyclopentadiene petroleum resin, polybutene, coumarone-indene resin, polyterpene resin, terpene based on 100 parts by weight of styrene-butadiene-styrene block copolymer 5 to 60 parts by weight of one or more tackifying resins selected from the group consisting of phenol resins, rosin, rosin esters, and hydrogenated additives thereof, 20 to 80 parts by weight of process oil, and polyethylene wax, vegetable wax, animal wax, interface Melt mixing at least 10 to 40 parts by weight of at least one neutralizing additive selected from the group consisting of an active agent and a fatty acid; And
Ii) dispersing 5 to 35 parts by weight of polyethylene nonwoven in an unmelted state relative to 100 parts by weight of the styrene-butadiene-styrene block copolymer in the molten mixture of iii).
Method for producing mesophilic dry asphalt modifier.
The method of claim 10,
Steps iii) and ii) are performed at a temperature of 110 to 125 ° C.
Method for producing mesophilic dry asphalt modifier.
The method of claim 10,
After step ii),
Cooling the mixture; And
Molding the cooled mixture into pellets;
Method for producing mesophilic dry asphalt modifier.
The method of claim 10,
In the step iii), further comprising mixing at least one additive selected from the group consisting of antioxidants, heat stabilizers, antistatic agents and lubricants
Method for producing mesophilic dry asphalt modifier.
The method of claim 10,
The polyethylene nonwoven fabric is characterized in that produced using polyethylene fibers
Method for producing mesophilic dry asphalt modifier.
15. The method of claim 14,
The polyethylene fiber has a melting temperature of 126 ~ 140 ℃, characterized in that the melt flow index is 10g / 10min or more
Method for producing mesophilic dry asphalt modifier.
The method of claim 10,
The polyethylene nonwoven fabric is characterized in that the thickness of 0.1 to 10 mm range
Method for producing mesophilic dry asphalt modifier.

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