CN1182199C - A stable polymer bituminous composition - Google Patents

Abstract

The present invention relates to a stable polymer asphalt composition which comprises 88 to 97.9 parts by weight of asphalt (1), 1 to 5 parts by weight of polymeric substance A (2), 1 to 5 parts by weight polymeric substance B (3) and 0.1 to 2 parts by weight of stabilizers (4). The softening temperature difference of the composition isolation test is smaller than or equal to 2.5 DEG C. The present invention can be stored for a long term, and the separation of polymer and asphalt does not occur in the storage process.

Description

A stable polymer bituminous composition

Technical field

The present invention relates to a bituminous material and more particularly to a stabilized polymer bituminous composition.

Background technique

As we all know, asphalt is an important road paving material, and some properties of asphalt can be modified by adding some high polymers to improve its performance, such as USP4,314,921 through a special high-speed shear colloid mill ) is dispersed in asphalt to achieve the purpose of improving the performance of asphalt, and the anti-high and low-temperature ability and anti-aging ability of the modified asphalt are obviously enhanced. After the shearing action is stopped, the dispersed PE particles in the asphalt are easy to aggregate, resulting in the layering of the PE phase and the asphalt phase, which is difficult to store stably and has certain limitations. It is mainly used for on-site mixing to modify asphalt.

USP5,348,994 provides a kind of preparation method of modified asphalt, adopts styrene-diene copolymer as modifier, first with solvent the modifier is dissolved, then with sulfonating agent the styrene-diene The copolymer and asphalt are sulfonated separately, the sulfonated polymer and asphalt are blended, and finally neutralized with a neutralizer to obtain a modified asphalt product. The product has good storage stability. It can be stored at 160°C for 3-5 days without delamination. Samples are taken from the top and bottom 1/3 of the product, and the difference in softening point does not exceed 4°C. The disadvantage is that the process is complicated, the requirements for equipment and process are strict, and the large amount of sulfonating agent is easy to cause pollution.

USP4,567,222 adds block SBS to asphalt, uses polysulfide as coupling agent, produces irreversible chemical bonds to improve the cohesion and flexibility of asphalt, and improves the ability of asphalt to resist rutting at high temperature and cope with cracking at low temperature. However, it must first be made into mother liquor, and the polymer and polysulfides are dissolved with crude oil atmospheric and vacuum distillate oil and then mixed with asphalt to obtain modified asphalt with good storage stability, but in the later stage of the operation process, the mother liquor needs to be The removal of light components in the process is relatively complicated and the removed light components are easy to cause environmental pollution.

USP4,868,245 introduces a variety of functional groups through active treatment of styrene-diene polymers, increases the polarity and reactivity of the polymer, and improves the compatibility of the polymer and asphalt. After the modified polymer is blended with asphalt, a modified asphalt with excellent performance and good storage stability can be obtained. Due to the particularity of its polymer, its use is limited. Once the non-modified styrene-diene polymer is replaced, the performance and storage stability of the product are difficult to be guaranteed.

In summary, it can be seen that the storage stability of modified asphalt is a problem that needs to be solved when asphalt is modified. Although the above patents provide some solutions, they also have certain limitations. For example, the preparation process is complicated. The equipment requirements are high, or the environment is polluted, so its application is subject to certain restrictions.

Contents of the invention

The purpose of the present invention is to provide a stable polymer asphalt composition on the basis of the prior art, while its high and low temperature performance is improved.

The polymer asphalt composition provided by the invention comprises:

(1): 88～97.9 parts (parts by weight) of asphalt;

(2): 1 to 5 parts (parts by weight) of type A polymer;

(3): 1 to 5 parts (parts by weight) of type B polymer;

(4): 0.1-2 parts (by weight) of a stabilizer.

Among them, the type A polymer is an elastomeric polymer, which is a series of polymers containing styrene and conjugated diene, wherein the content of styrene is 20-50%, and the elastomeric polymer can be one or more polymers. The conjugated diene is isoprene or butadiene. The styrene-diene copolymer can be a diblock polymer, a triblock polymer, or styrene-butadiene rubber.

Type B polymer is selected from polyethylene wax, α-olefin, unsaturated epoxide and unsaturated carboxylic acid ester copolymer, α-olefin and unsaturated carboxylic acid ester copolymer, glycidyl ester compound, petroleum resin 1, or a mixture of one or more of coumarone resins.

The stabilizer is one or a mixture of more than one selected from organic peroxides, metal oxides, sulfur, and vulcanization accelerators.

The softening point difference of the segregation test of the polymer asphalt composition provided by the invention is less than or equal to 2.5° C., and the product can be stored for a long time without separation of the polymer and asphalt during storage.

Detailed ways

The polymer asphalt composition provided by the invention comprises:

(1) 88 to 97.9 parts (parts by weight) of asphalt;

(2) 1 to 5 parts (parts by weight) of Class A polymer;

(3) 1 to 5 parts (parts by weight) of Class B polymer;

(4) 0.1 to 2 parts (by weight) of a stabilizer.

Wherein the asphalt component is a mixture of one or more selected from petroleum asphalt, coal tar asphalt, oil sands asphalt, and natural asphalt, the saturated hydrocarbon of the asphalt is 5-25% by weight, and the aromatic hydrocarbon is 30-60% by weight %, colloids are 20-40% by weight, and asphaltenes are 0.05-15% by weight.

Type A polymer is an elastomeric polymer, which is a series of polymers containing styrene and conjugated dienes, wherein the content of styrene is 20-50%, and the elastomeric polymer can be one or more polymers. The conjugated diene is isoprene or butadiene. Type A polymers are mainly used to improve the high and low temperature performance of asphalt and enhance the viscosity and toughness of asphalt.

Type B polymer is selected from polyethylene wax, α-olefin, unsaturated epoxide and unsaturated carboxylic acid ester copolymer, α-olefin and unsaturated carboxylic acid ester copolymer, glycidyl ester compound, petroleum resin 1, or a mixture of one or more of coumarone resins. Type B polymers are mainly used to improve the compatibility with asphalt and promote the stable dispersion of polymers in asphalt.

The stabilizer is one or a mixture of more than one selected from organic peroxides, metal oxides, sulfur, and vulcanization accelerators. The stabilizer enables the polymer to form a cross-linked spatial network structure in the asphalt, and at the same time allows part of the asphalt to be grafted to the polymer network structure, preventing the separation of the asphalt phase and the polymer phase, thereby increasing the storage stability of the modified asphalt sex.

The preparation method of the asphalt composition provided by the invention is as follows: heating 88-97.9 parts (parts by weight) of asphalt to 120-220°C, preferably 150-200°C, adding 1-5 parts (parts by weight) of A Class polymers, 1-5 parts (weight parts) of B-type polymers and 0.1-2 parts (weight parts) of stabilizers are reacted under high shear for 0.5-4 hours, preferably 1-3 hours, The rotational speed is 500-5,000 revolutions per minute (rpm), preferably 1,000-3,000 rpm.

The present invention prepares a stable polymer asphalt composition by selecting polymers with different compositions or structures for compounding, and utilizes the complementary effects between their properties. Polymers with different compositions or structures have different properties after asphalt modification. Impact. Generally speaking, polymers with lower molecular weight or with polar functional groups in their molecular structure have better compatibility with asphalt, and have good storage stability after blending with asphalt. The improvement is not large, which means that the softening point of the modified asphalt does not increase much, and the use is subject to certain restrictions, which has relatively large limitations. The high-molecular-weight polymer has a significant effect on improving the high-temperature performance of asphalt, and the softening point of asphalt after modification increases greatly. Unstable dispersion in asphalt, easy to aggregate. The invention mixes two or more kinds of polymers with different compositions or structures, fully utilizes the different improving effects of different types of polymers on asphalt properties, and prepares a polymer asphalt composition capable of stable storage.

The storage stability of the polymer asphalt composition means that the asphalt and the polymer in the composition do not undergo phase separation after the composition is placed at a certain temperature for a certain period of time. Characterized by segregation test, the characterization method is as follows: pour the polymer asphalt composition into a long round tube, place it at 163±5°C for 48 hours, take the top and bottom 1/3 of the tube to measure its softening point, When the difference between the upper and lower softening points is less than or equal to 2.5°C, it is considered that the phase separation between the asphalt and the polymer does not occur, and the polymer asphalt composition is stable and has good storage performance.

The softening point difference of the polymer asphalt composition provided by the invention in the segregation test is less than or equal to 2.5° C., and meanwhile, its high and low temperature performance is improved. The product can be stored for a long time without separation of polymer and bitumen during storage. The preparation process of the composition is simple, the preparation method is flexible, the requirements for equipment are not high, and no reagents causing environmental pollution are used.

The following examples will further illustrate the method, but the method is not limited thereby. The properties of asphalt raw materials A and B are listed in Table 1, the test results of Comparative Examples 1-2 and Examples 1-2 are listed in Table 2, and the test results of Comparative Examples 3-4 and Examples 3-4 are listed in Table 3.

Comparative example 1

This comparative example illustrates the dispersion state of type A polymer in bitumen A and the performance of the modified bitumen.

In a 1-liter reactor, 94 parts of bitumen A were heated to 160 °C, and then 5 parts (by weight) of SBS (manufactured by Maoming Petrochemical Company, molecular weight 285,000) and 1 part (by weight) of element S were added. A mixer (manufactured by Jiangsu Qidong Chemical Equipment Factory, model L100) was mixed at 160° C. for 60 minutes. After the mixing is stopped, it can be observed that the surface of the asphalt is uniform and there are no particles visible to the naked eye, but the segregation test results show that the difference between the upper and lower softening points is 32°C. It can be considered that the dispersion of SBS in the asphalt is unstable, and the SBS in the asphalt will change with the storage time. extended and layered. The test results show that the softening point of the modified asphalt has been greatly improved compared with the base asphalt, indicating that the high temperature performance of the modified asphalt has been greatly improved.

Comparative example 2

This comparative example illustrates the dispersion state of polymer B in bitumen A and the performance of the modified bitumen.

Compared with Comparative Example 1, in this Comparative Example, the SBS in Comparative Example 1 was replaced by polyethylene wax with a lower molecular weight (produced by Shanghai Zhonghua Chemical Plant, with a molecular weight of 5,000-10,000). The test results found that the difference in segregation softening point of the sample was only 0.3°C, indicating that the low molecular weight polyethylene wax was dispersed in the asphalt very stably without segregation, but the softening point of the modified asphalt had a small increase compared with the base asphalt. The high temperature performance of asphalt is not much improved.

Example 1

This example illustrates the present invention. A polymer asphalt composition with good storage stability is prepared by compounding two different types of A-type polymers and B-type polymers.

Compared with Comparative Example 1, this embodiment reduces the amount of SBS in Comparative Example 1 from 5 parts (by weight) to 3 parts and adds 2 parts (by weight) of polyethylene wax with a lower molecular weight. The test results found that the difference in the segregation softening point of the samples was 1.2°C, indicating that the two polymers after compounding were dispersed stably in the asphalt without segregation, and the softening point of the modified asphalt was significantly different from that of the base asphalt. It shows that the modified asphalt with stable storage and good high temperature performance can be obtained after compounding polymers with different compositions and structures.

Example 2

Compared with Example 1, the polyethylene wax was replaced by glycidyl ester (Tianjin Jindong Chemical Plant), and the test results showed that the same polymer asphalt composition with good storage stability and good high-temperature performance could be obtained.

Comparative example 3

This comparative example illustrates the dispersion of type A polymer in asphalt B and the performance of the modified asphalt.

In a 1-liter reactor, heat 94 parts of bitumen B to 160°C, then add 5 parts (by weight) of SBS (manufactured by Maoming Petrochemical Company, molecular weight 285,000) and 1 part (by weight) of element S, and use high-shear A mixer (manufactured by Jiangsu Qidong Chemical Equipment Factory, model L100) was mixed at 160° C. for 60 minutes. After the mixing is stopped, it can be observed that the surface of the asphalt is uniform and there are no particles visible to the naked eye, but the segregation test results show that the difference between the upper and lower softening points is 32°C. It can be considered that the dispersion of SBS in the asphalt is unstable, and the SBS in the asphalt will change with the storage time. extended and layered. The test results show that the softening point of the modified asphalt has been greatly improved compared with the base asphalt, indicating that the high temperature performance of the modified asphalt has been greatly improved.

Comparative example 4

This comparative example illustrates the dispersion state of B-type polymer in asphalt B and the performance of the modified asphalt.

Compared with Comparative Example 3, in this Comparative Example, the SBS in Comparative Example 3 was replaced by polyethylene wax with a lower molecular weight (produced by Shanghai Zhonghua Chemical Plant, with a molecular weight of 5,000-10,000). The test results found that the difference in segregation softening point of the sample was only 0.3°C, indicating that the low molecular weight polyethylene wax was dispersed in the asphalt very stably without segregation, but the softening point of the modified asphalt had a small increase compared with the base asphalt. The high temperature performance of asphalt is not much improved.

Example 3

This example illustrates the present invention. A polymer asphalt composition with good storage stability is prepared by compounding two different types of A-type polymers and B-type polymers.

Compared with Comparative Example 3, this embodiment reduces the amount of SBS in Comparative Example 3 from 5 parts (by weight) to 3 parts and adds 2 parts (by weight) of polyethylene wax with a lower molecular weight. The test results found that the difference in the segregation softening point of the samples was 1.2°C, indicating that the two polymers after compounding were dispersed stably in the asphalt without segregation, and the softening point of the modified asphalt was significantly different from that of the base asphalt. It shows that the modified asphalt with stable storage and good high temperature performance can be obtained after compounding polymers with different compositions and structures.

Example 4

Compared with Example 3, the polyethylene wax was replaced by glycidyl ester (Tianjin Jindong Chemical Plant), and the test results showed that the polymer asphalt composition with good storage stability and good high-temperature performance could also be obtained.

Table 1 Asphalt A Asphalt B Penetration (25℃, 100g, 5s), 1/10mm softening point (R & B), ℃ ductility (15℃, 5mm/min), cm ductility (5℃, 5mm/min), cm density ( 25℃), g/ ^cm3 10543.5>150<51.005 8544.4>150<51.016 Film oven test (163°C, 5h) Evaporation loss, m% penetration ratio (25°C), % ductility (15°C, 5mm/min), cm -0.0361.7>150 -0.0771>150 Four components Saturated part (SA), m% aromatic part (AR), m% gum (RE), m% asphaltene (AS), m% 10.654.233.41.8 9.052.032.66.4

Table 2 Test No. Comparative example 1 Comparative example 2 Example 1 Example 2 Composition composition (weight part) Asphalt A 94 94 94 94 Class A polymer SBS (F411x) 5 0 3 3 Class B polymer 0 5 2 2 sulfur 1 1 1 1 composition properties Penetration (25°C), 1/10mm 72 80 76 73 Softening point (R & B), ℃ 78.5 48.4 60.3 65 Ductility (5℃), cm 64 29 42 48 Film oven (163°C, 5h) Penetration ratio (25°C), % 81.4 77.1 74.5 82.0 Ductility (5℃), cm 42 20 28 33 Segregation test (163℃, 48h) The difference between upper and lower softening point, ℃ 32 0.3 1.2 2.2 stability Difference good good good

table 3 Test No. Comparative example 3 Comparative example 4 Example 3 Example 4 Composition composition (weight part) Asphalt B 94 94 94 94 Class A polymer SBS (F411x) 5 0 3 3 Class B polymer 0 5 2 2 sulfur 1 1 1 1 composition properties Penetration (25°C), 1/10mm 53 64 58 56 Softening point (R & B), ℃ 85.4 52.4 65.2 77.1 Ductility (5℃), cm 45 16 32 36 Film oven (163°C, 5h) Penetration ratio (25°C), % 85.2 79.6 83.2 82.7 Ductility (5℃), cm 29 13 twenty two twenty four Segregation test (163℃, 48h) The difference between upper and lower softening point, ℃ 36 0.5 1.8 2.4 stability Difference good good good

Claims (4)

1. A stabilized polymer bituminous composition comprising: (1) 88-97.9 parts by weight asphalt; (2) 1 to 5 parts by weight of type A polymer, the type A polymer is an elastomeric polymer, which is a series of polymers containing styrene and conjugated dienes, wherein the content of styrene is 20% to 50%, The elastomeric polymer can be one or more polymers, and the conjugated diene is isoprene or butadiene; (3) 1 to 5 parts by weight of type B polymer, the type B polymer is polyethylene wax and/or glycidyl ester compound; (4) 0.1 to 2 parts by weight of a stabilizer. 2. according to the composition of claim 1, it is characterized in that described asphalt is selected from one or more mixtures among petroleum asphalt, coal tar pitch, oil sands asphalt, natural asphalt, and the saturated hydrocarbon of asphalt is 5-25% by weight, 30-60% by weight of aromatic hydrocarbons, 20-40% by weight of colloids, and 0.05-15% by weight of asphaltenes. 3. The composition according to claim 1, characterized in that said styrene-diene copolymer can be a diblock polymer, a triblock polymer, or styrene-butadiene rubber. 4. The composition according to claim 1, characterized in that said stabilizer is one or more mixtures selected from organic peroxides, metal oxides, sulfur, and vulcanization accelerators.