WO2008037168A1

WO2008037168A1 - A flame retardant modifier for asphalt

Info

Publication number: WO2008037168A1
Application number: PCT/CN2007/002290
Authority: WO
Inventors: Ping Zhang; Polo He
Original assignee: Shenzhen Oceanpower Industrial Co., Ltd.; Shenzhen Oceanpower Engineering Technology Co., Ltd.
Priority date: 2006-09-28
Filing date: 2007-07-30
Publication date: 2008-04-03
Also published as: CN101153116B; CN101153116A

Abstract

A flame retardant modifier for asphalt in the form of pellets, consists of 20-45 pts.wt. red phosphorus,15-30 pts.wt. hydrated magnesium silicate, 5-15 pts.wt.smoke suppressant,1-10 pts.wt.coupling agent (i.e.C16-C18 fatty acid) and 15-25 pts.wt polyolefin.The preparing process of the flame retardant modifier for asphalt is disclosed.

Description

Leyoke flame retardant, agent

Technical field

The present invention relates to an asphalt flame retardant modifier, and more particularly to a bitumen-specific functional modification additive. Background technique

Asphalt is the final product of petroleum refining. It is a cheap and abundant building material widely used in construction. It is used for waterproofing, moisture proof, anti-corrosion, anti-rust and anti-leakage. Some of its properties are unmatched by synthetic rubber and synthetic resins. However, asphalt has the characteristics of being easy to burn, burning a large amount of black smoke, being heated by molten droplets, flowing, and has a great fire risk, and its application is also limited. For this reason, the research on the incombustibility of asphalt has great practical significance.

With the development of highways in China, the number of road tunnels has also increased. Since cement concrete is resistant to water and non-combustible, the pavement pavement has still mainly used cement pavement. However, with the improvement of road users' quality requirements for road driving, the smooth, wear-resistant and low-noise asphalt concrete pavement may replace cement concrete pavement, and gradually become the mainstream of tunnel pavement development.

Article 15.3 of the “Code for Design of Highway Tunnels” (JTG D70-2004) stipulates: “Cement concrete pavements may be used for road tunnels at all levels. If necessary, asphalt pavements with good flame retardancy, good for photoelectric illumination and good reflective properties may be used. Structure". At present, the tunnel adopts a flame-retardant asphalt pavement with good anti-slip property, low noise and comfortable driving, which is becoming a development trend.

According to reports at home and abroad, during the use of asphalt pavement in tunnels, fires caused by traffic accidents are a problem that must be paid attention to during the use of tunnel pavements. When a traffic accident occurred in the tunnel, the road surface caught fire, the fire was developing rapidly, and people were too late to evacuate, causing more casualties and causing unnecessary losses to the country and people's lives and property. In addition, a large amount of black smoke is generated when the asphalt is on fire, which causes serious pollution to the environment.

At present, the idea of China's flame retardant asphalt pavement is the conventional flame retardant asphalt idea. · By adding powder flame retardant to the asphalt, it is flame retardant. This production process is complicated and has environmental pollution and other defects. Because the density of flame retardant and asphalt is very different, the flame retardant can not be stably existed in the asphalt, and the asphalt has serious segregation phenomenon. In order to slow the separation of the asphalt, the addition amount of the flame retardant will be greatly affected. Limitations, the flame retardancy of asphalt will also have significant limitations.

Powder granulation technology is one of the most important branches of powder and granule process. With the environmental protection demand and the automation of the production process, its importance is becoming more and more obvious. The granulation of powdery products has become the world's powder aftertreatment technology. The inevitable trend. The flame retardant theory of asphalt is mainly based on polymer The flame retardant mature flame retardant theory, with the wide application of flame retardant masterbatch in the flame retardant of plastics and household appliances, the development of granular asphalt flame retardant modifier is also an inevitable product on the development road of asphalt pavement flame retardant technology. Summary of the invention

The object of the present invention is to provide an asphalt flame retardant modifier capable of improving the flame retardancy of an asphalt pavement. The asphalt flame retardant modifier has the characteristics of good granularity, good dispersibility and easy addition, and after being added to the asphalt mixture, The flame retardant performance of the asphalt mixture is effectively improved under the premise of no influence on the road performance of the asphalt.

Another object of the present invention is to provide a method for preparing the above asphalt flame retardant modifier.

A flame retardant modifier for asphalt, in the form of granules, consisting of: red phosphorus 20 ~ 45 parts; hydrated magnesium silicate 15 ~ 30 parts; smoke suppressant 5 ~ 15 parts; coupling agent, C16 - C18 1 ~ 10 parts of fatty acids; 15 ~ 25 parts of polyolefin.

Among the above asphalt flame retardant modifier components, red phosphorus and hydrated magnesium silicate are flame retardants; the smoke suppressant is one of hydroxide, zinc borate, copper trioxide, ammonium copper phosphate or tin oxide. The hydroxide is magnesium hydroxide or aluminum hydroxide; the polythene is one of polyethylene, polypropylene, polystyrene, PVC, EVA or LDPE, which is a carrier for the synthetic masterbatch; the coupling agent is a kind of package The organic substance which organically oxidizes the flame retardant on the surface of the flame retardant effectively improves the dispersibility of the asphalt flame retardant modifier.

The preparation method of the above asphalt flame retardant modifier comprises the following steps:

1) mixing the above raw materials in the above ratio under the conditions of 20 minutes/rev;

2) The mixture is heated to 80 ° C in 10 s, then raised to 150 ° C in 15 s, and finally heated to 200 ° C in 5 s;

3) The mixture is cooled, extruded, granulated, filled, and finished.

The asphalt flame retardant modifier of the invention has the characteristics of good dispersibility, easy addition, safety and environmental protection, improves production efficiency, has no working environment pollution, less equipment corrosion; uses red brick as a flame retardant, environmental protection; The fuel composition is properly matched, and the synergistic effect of various flame retardants is fully utilized, and high efficiency; direct blending and addition, simplifying the production process and reducing the production cost. detailed description

A flame retardant modifier for asphalt, in the form of granules, consisting of: red phosphorus 20 ~ 45 parts; hydrated magnesium silicate 15 ~ 30 parts; smoke suppressant 5 ~ 15 parts; coupling agent, C16 C18 Fatty acid 1 - 10 parts; polyolefin 15 ~ 25 parts.

Among the above asphalt flame retardant modifier components, red phosphorus and hydrated magnesium silicate are flame retardants; the smoke suppressant is one of hydroxide, boric acid, copper trioxide, ammonium copper phosphate or tin oxide. Hydrogen hydroxide Magnesium oxide or aluminum hydroxide; the polythene is one of polyethylene, polypropylene, polystyrene, PVC, EVA or LDPE, which is a carrier for the synthetic masterbatch; the coupling agent is a surface coated on the flame retardant The organic substance that organicizes the flame retardant effectively improves the dispersibility of the asphalt flame retardant modifier.

The flame retardant interferes with the combustion process in the flame zone and the condensed phase zone by physical or chemical action to achieve a reduced combustion rate and achieve the purpose of flame retardancy. It is generally achieved by one or more of the following methods: endothermic effect, covering isolation effect, transfer effect, inhibition effect, synergistic effect. The flame retardant mechanism of flame retardant is summarized as: resistance heat insulation mechanism, gas phase flame retardant mechanism, solid phase flame retardant mechanism.

The flame retardant mechanism of red phosphorus is: thermal oxidation to produce polymetaphosphoric acid, polyphosphoric acid is a non-volatile stable compound, forming a barrier layer on the surface of the combustion. Further, since the polyphosphoric acid dehydration promotes carbonization, a carbonized film is formed on the surface, thereby providing a flame retarding effect. The flame retardant mechanism of hydrated magnesium silicate is: When the SiO2 coating is formed during combustion, it plays the dual role of heat insulation and shielding. The mechanism of the smoke suppressant magnesium hydroxide flame retardant and smoke suppression is: They mainly generate endothermic decomposition reaction in the initial stage of material combustion, generate a large amount of water, and further evaporate and absorb a large amount of heat energy, thereby reducing the temperature of the combustion system and the dilution system. Effect of oxygen concentration; flame retardant mechanism of smoke suppressant zinc borate: Zinc borate can exert flame retardant effect in both condensed phase and gas phase. It melts at high temperatures to form a glassy coating, which is subsequently dehydrated at elevated temperatures. Evaporation of water and other effects of water vapor help to self-extinguish the combustion. The dehydrated zinc borate promotes the formation of an inorganic carbon layer, is difficult to ignite and burn, and has an insulating effect.

Example 1

Weighed by weight: red phosphorus 450g; hydrated magnesium silicate 150g; magnesium hydroxide 150g; C16 ~ C18 fatty acid 100g; polyethylene 150g. Under the condition of 20 minutes/rev, the various raw materials were uniformly mixed; the mixture was heated to 80 ° C in 10 s, then heated to 150 ° C in 15 s, and finally heated to 20 (TC in 5 s; the mixture was cooled, Extrusion molding, granulation, barreling, and finished products.

Example 2:

Weighed by weight: red phosphorus 450g; hydrated magnesium silicate 240g; aluminum hydroxide 50g; C16 ~ C18 fatty acid 10g; polyene polystyrene 250g. The preparation method was the same as in Example 1.

Example 3:

Weighed by weight: red phosphorus 340g; hydrated magnesium silicate 300g; zinc borate 100g; C16-C18 fatty acid 60g; polyethylene 200g. The preparation method was the same as in Example 1.

Example 4:

Weighed by weight: red phosphorus 200g; iced magnesium silicate 300g; magnesium hydroxide 150g; C16 ~ C18 fatty acid 100g; polypropylene 250g. The preparation method was the same as in Example 1.

The flame retardant asphalt obtained in the examples was tested according to the following standards, and the data obtained are as follows: Example 1 Example 2 Example 3 Example 4 Appearance appearance Violet particle purple red particle purple red particle purple red particle ignition point °c 335 341 367 386 < 320 °C Application:

The main application mode of the asphalt flame retardant modifier in the invention is to add to the asphalt mixture, and the asphalt mixture is flame-retardant modified, and the road performance of the flame retardant asphalt mixture is different according to the asphalt and the grade used. Different, but basically guarantees the road performance of the asphalt mixture when the asphalt flame retardant modifier is not added. The flame retardant asphalt mixture includes the following components: polymer modified asphalt, asphalt flame retardant modifier, aggregate, filler, fiber stabilizer, and the material properties and proportions of each component are as follows:

Polymer modified asphalt: polymer modified asphalt, in line with (JTG F40 - 2004) "Technical Specifications for Construction of Highway Asphalt Pavement".

Asphalt flame retardant modifier: It is a bitumen modifier with flame retardant and smoke suppressing effect synthesized by a certain synthetic process using various flame retardants and smoke suppressants as raw materials. The amount added is 5% - 30% of the mass of the polymer modified asphalt.

The amount of polymer modified asphalt and asphalt flame retardant modifier mixture in the flame retardant asphalt mixture is 5.7% ~ 6.4%.

Aggregate: including but not limited to basalt or diabase or limestone, technical requirements are as follows: Aggregate technical requirements

Filler: limestone or slaked lime or cement;

The aggregate of the aggregate and packing is:

Gradation range

Fiber Stabilizers: including but not limited to polyacrylonitrile or polyester or lignin Dimension. The dosage is 0% - 0.5% of the amount of the mixture shield.

Specific implementation: '

' Aggregate: Basalt, in accordance with Table 1.

Filler: Limestone ore powder.

The grade of mineral material (aggregate + filler) is:

Polymer modified asphalt: SBS modified asphalt (I-D), produced by Maoming Petrochemical; Asphalt flame retardant modifier: Prepared by the example, the amount is 18% of polymer modified asphalt; Polymer modification Asphalt + asphalt flame retardant modifier: Aggregate + filler = 5.9: 100;

Fiber Stabilizer: Delanet AS-II polyacrylonitrile fiber, the blending amount is 0.2% of the total mass of the mixture.

Road performance test of flame retardant asphalt mixture - The test results of the mixture are as follows:

The tests in the test are tested according to the following standards: Flame-retardant modified asphalt mixture rutting test according to T 0719- 1993 asphalt mixture rutting test; flame retardant modified asphalt mixture Marshall stability test according to T 0709 - 1993 asphalt mixing Marshall stability test; Flame-retardant modified asphalt mixture freeze-thaw split test according to T 0729 - 2000 asphalt freeze-thaw split test test.

SMA-13 mixed vehicle Marshall test results

Whetstone ratio Void ratio VMA VFA Stability Flow value (%) ( % ) (%) (%) (kN) (mm)

SMA-13 modified asphalt 5.9 4.0 18.0 78.0 7.6 2.3

SMA-13 modified asphalt addition example 1 5.9 4.2 18.3 . 77.0 7.2 2.5

SMA-13 modified asphalt addition example 2 5.9 4.1 18.2 77.0 ' 8.2 2.4

SMA- 13 modified asphalt addition example 3 5.9 4.0 18.1 78.0 7.5 2.1

SMA-13 modified asphalt addition example 4 5.9 4.1 18.2 77.0 7.5 2.3

Standard Requirements 3-4 <17.0 75-85 <6.0

SMA-13 mixture rutting test results

Dynamic stability (time / mm) final deformation (face)

SMA-13 modified asphalt 8250 1.31

SMA-13 modified asphalt addition example 1 7875 1.84

SMA-13 modified asphalt plus example 2 7875 0.90

SMA-13 modified asphalt plus Example 3 9000 1.19 SMA-13 modified asphalt plus example 4 8750 1. 33

Standard requirement < 2400

SMA-13 mixture residue stability test results

Project stability UN ) water immersion stability (kN) residual stability ratio (%)

SMA-13 modified asphalt 7. 6 6. 9 90. 8%

SMA-13 modified asphalt addition example 1 7. 2 6. 4 88. 9%

SMA-13 modified asphalt addition example 2 7. 6 7. 0

SMA-13 modified asphalt addition example 3 7. 5 6. 8 92. 1%

SMA-13 modified asphalt addition example 4 7. 5 6. 9 92. 0% Standard requirements "80%

SMA-13 mixture freeze-thaw split test results

Splitting tensile strength, freeze-thaw splitting, freeze-thaw splitting strength ratio

( Mpa ) Strength (Mpa ) ( % )

SMA-13 modified asphalt 0. 60 0. 53

SMA-13 modified asphalt plus Example 1 0. 59 0. 50 oo

SMA-13 modified asphalt addition example 2 0. 61 0. 51 83. 6%

SMA-13 modified asphalt addition example 3 0. 60 0. 53 88. 3%

SMA-13 modified asphalt addition example 4 0. 60 0. 51 85. 0% Standard requirements < 80% Flame-retardant asphalt mixture flame retardant test results are as follows:

The determination of the asphalt oxygen index is basically the same as that of other materials, but the final application of the road asphalt is to make the asphalt mixture spread on the road surface. In the asphalt mixture, the asphalt is adsorbed as a binder by the filler in the asphalt mixture to form a binder of the binder aggregate. Therefore, the asphalt mixture is burned together with the filler during the combustion process.

In order to better reflect the asphalt burning process in the determination of asphalt oxygen index, we uniformly mix the commonly used asphalt mixture in the asphalt before preparing the asphalt oxygen index spline according to the standard GB/T 2406 "Plastics Burning Performance Test Method Oxygen Index". Material filler ^ "one mineral powder. In asphalt mixture The mass ratio of asphalt to filler (powder to rubber ratio) is generally 1:0.8 - 1 : 1.2, so the ratio of asphalt to mineral powder in the asphalt oxygen index spline is set to 1:1. After the oxygen index spline is prepared, the asphalt oxygen index is determined according to GB/T 2406 "Plastics Burning Performance Test Method Oxygen Index".

The flame retardant performance test results of the flame retardant asphalt pavement are taken as follows:

In order to compare the flame retardant properties of asphalt flame retardant modifiers in different cases, we measured the oxygen index of the asphalt with the same blending amount of 18% for comparison.

It can be seen from the test data that after adding the asphalt flame retardant additive to the asphalt mixture, the asphalt performance of the asphalt mixture is improved, and the road performance of the asphalt is not changed much, and the road performance of the original asphalt can be basically guaranteed. . It can be seen that when the asphalt flame retardant additive is added to other different grade asphalt mixtures, the road performance of the original asphalt mixture can be ensured.

The asphalt flame retardant modifier of the invention has the characteristics of no environmental protection, and the safety and environmental protection meets the requirements of the European SGS. It can effectively improve the flame retardant performance of asphalt pavement. When burning on asphalt pavement, a stable carbonized layer is formed on the combustion surface, causing self-extinguishing phenomenon to terminate the combustion. In addition, hydroxides such as magnesium hydroxide mainly undergo thermal decomposition reaction at the initial stage of combustion of the substance, generating a large amount of water. The water is further evaporated to absorb a large amount of heat energy, which serves to lower the temperature of the combustion system and the oxygen concentration in the dilution system. If fire occurs on the flame retardant asphalt pavement, there will be less casualties and property losses, which have broader application prospects and good social and economic benefits. The preparation method is simple, effective, economical, convenient to use, and wide in application.

Claims

Rights request

1. A bitumen flame retardant modifier, in the form of granules, consisting of:

Red dull ~ ~ 45 copies;

Hydrated magnesium silicate - 30 parts;

Smoke suppressant - 15 parts;

Coupling agent, C16 ~ C18 fatty acid ~ 10 parts;

Polyolefin 5-25 parts;

In the above asphalt flame retardant modifier component, the smoke suppressant is one of hydroxide, zinc borate, copper trioxide, ammonium copper phosphate or tin oxide, and the hydroxide is magnesium hydroxide or aluminum hydroxide; The dilute hydrocarbon is one of polyethylene, polypropylene, polystyrene, PVC, EVA or LDPE.

2. A method of preparing the asphalt flame retardant modifier of claim 1 comprising the steps of:

1) Mixing the raw materials of the content of claim 1 at 20 minutes/rev; 2) heating the mixture to 80 ° C in 10 s, then raising the temperature to 150 ° C in 15 s, and finally

The temperature was raised to 200 °C in 5s;

3) cooling the mixture, extruding, granulating, barreling, and obtaining