CN113773661A - Preparation method of self-made polyurethane modified asphalt - Google Patents

Preparation method of self-made polyurethane modified asphalt Download PDF

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CN113773661A
CN113773661A CN202111121902.7A CN202111121902A CN113773661A CN 113773661 A CN113773661 A CN 113773661A CN 202111121902 A CN202111121902 A CN 202111121902A CN 113773661 A CN113773661 A CN 113773661A
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asphalt
polyurethane
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tpu
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王志臣
郭乃胜
金鑫
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Dalian Maritime University
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Dalian Maritime University
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    • C08L95/00—Compositions of bituminous materials, e.g. asphalt, tar, pitch
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    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
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Abstract

The invention discloses a preparation method of self-made polyurethane modified asphalt, which comprises the following steps: (1) self-made polyurethane modifier; (2) and adding the self-made polyurethane modifier into the matrix asphalt to prepare the polyurethane modified asphalt. The method has very important values for solving the damage phenomena of cracking, rutting and the like of the asphalt pavement under the natural environment and the driving load condition, prolonging the service life of the road, improving the integrity, smoothness and water tightness of the asphalt pavement and improving the durability and driving comfort of the asphalt pavement. The method can efficiently and quickly prepare the polyurethane modified asphalt, shorten the development period of the modified asphalt, simplify the production process, reduce the production energy consumption, and solve the problems of easy aging of the matrix asphalt and the like.

Description

Preparation method of self-made polyurethane modified asphalt
Technical Field
The invention relates to a preparation method of self-made polyurethane modified asphalt, belonging to the technical field of road modified asphalt cement.
Background
With the rapid development of highway construction scale in China, the asphalt concrete pavement is widely applied to roads as an important pavement structure form. The pavement performance and the service life of the asphalt concrete pavement are greatly determined by the service performance and the service effect of the modifier, if the asphalt does not meet the quality standard suitable for the local climatic conditions and the service requirements, the temperature shrinkage or the temperature fatigue stress of an asphalt surface layer is larger than the tensile strength of the asphalt mixture, and cracks and other diseases occur. Therefore, how to improve the service performance of the asphalt pavement and meet the requirement of traffic development is one of the important subjects faced by road workers in China.
The existing traditional polymer (such as SBR, SBS, rubber powder and the like) modified asphalt has relatively complex preparation process and is difficult to meet the severe use requirement of the current high-grade highway. The polymer modifier is generally expensive in price and complex in production process, so that the road building cost is increased on one hand; on the other hand, the traditional polymer modifier has poor compatibility with asphalt, and the improvement effect on the asphalt is difficult to realize. Therefore, it is not conducive to popularization and development.
Disclosure of Invention
The invention aims to provide a preparation method of self-made polyurethane modified asphalt, which adds a proper amount of polyurethane (pre-synthesized according to the application requirement of a road) modifier into matrix asphalt for optimized modification, improves and prolongs the durability and the service life of a road surface.
In view of the fact that the conventional polymer modified asphalt used at present has a single modification effect and is difficult to adapt to the pavement performance requirement of high-grade pavement, higher requirements are put forward on the service performance of the polymer. The invention provides a preparation method of self-made polyurethane modified matrix asphalt by fully considering the requirements of durability and pavement performance of a high-grade asphalt cementing material and starting from a micro and macro characterization method.
The technical scheme of the invention is as follows:
a preparation method of self-made polyurethane modified matrix asphalt comprises the following steps:
(1) preparation of self-made polyurethane modifier
Dehydrating polybutylene adipate-polyester glycol (PBA) or polytetramethylene ether glycol (PTMEG) for 60-90 min at 100-110 ℃ and 200-500 rpm under the condition of nitrogen; then, reducing the temperature of the system to 70-80 ℃, adding melted 4,4' -diphenylmethane diisocyanate (MDI), keeping the temperature and the rotating speed unchanged to react for 1-2 hours, and when the viscosity of the system gradually increases and blue light is emitted, successfully preparing the polyurethane prepolymer; and (3) reducing the temperature of the system to 50 ℃, adding 1, 4-Butanediol (BDO), increasing the rotating speed to 300-400 rpm, rapidly stirring for 2-10 min, stopping stirring, and curing in an oven at 100-120 ℃ for 24h to obtain the required self-made polyurethane (TPU).
In the synthesis of a sample with the hard segment content of MDI greater than 40% or the isocyanate index greater than 1.05, the viscosity of the system is rapidly increased after BDO is added, and the stirring time is properly adjusted according to the viscosity in order to facilitate discharging.
The polyurethane modifier comprises, by weight, 47-100 parts of polybutylene adipate-co-polyester glycol (PBA), 48-100 parts of polytetramethylene ether glycol (PTMEG), 21.39-22.59 parts of 4,4' -diphenylmethane diisocyanate (MDI) and 3.67-13.67 parts of 1, 4-Butanediol (BDO).
(2) Preparation of polyurethane modified asphalt
Adding the self-made polyurethane modifier into the mixture preheated to T1In the matrix asphalt, a shearing machine is adopted, and the rotating speed is S DEG C1Shearing t under the condition of r/min1h; subsequently, the temperature is raised to T2Adjusting the rotation speed to S DEG C2r/min, shear t2h; and after the shearing is stopped, preparing the polyurethane modified asphalt.
The raw materials for preparing the polyurethane modified asphalt comprise the following components in parts by weight: 1-7 parts of self-made polyurethane modifier and 85-100 parts of matrix asphalt;
T1145 to 165, T2150 to 170, S13000 to 5000, S23000 to 5000, t10.5 to 1, t20.5 to 1.
Further, the molecular weight of polytetramethylene glycol adipate polyester glycol (PBA) or polytetramethylene ether glycol (PTMEG) is 1000-2000.
Further, S1And S2The same or different.
Further, the matrix asphalt is rock asphalt.
The invention selects diphenylmethane-4, 4' -diisocyanato (MDI) as a hard segment, and aims to ensure that the synthesized TPU hard segments are mutually aggregated and compacted and the physical property is enhanced; polytetramethylene ether glycol (PTMEG) with molecular weight of 1000-2000-one or butanediol adipate polyester diol (PBA) is selected as soft-segment oligomer diol, and in order to enable the TPU to form a linear long chain in actual production; the addition of the chain extender 1, 4-Butanediol (BDO) is beneficial to promoting the aggregation of hard segments and urethane groups, and the addition of BDO for chain extension reaction in the second step in the synthesis reaction process can improve the polymerization reaction efficiency.
Firstly, synthesizing polyurethane modifiers with different molecular weights, soft-hard segment ratios and isocyanate indexes according to the application characteristics of roads, and then respectively adding the self-made polyurethane modifiers into the matrix asphalt to prepare the polyurethane modified asphalt. According to the requirements for the pavement performance of the asphalt concrete pavement in the current specification, the pavement performance test is carried out on the self-made polyurethane modified matrix asphalt, and the method has very important influence on prolonging the service life of the asphalt pavement and fundamentally preventing the premature occurrence of diseases of the asphalt pavement.
The invention has the beneficial effects that:
the method for modifying the matrix asphalt by the self-made polyurethane modifier provided by the invention enables the prepared polyurethane modified asphalt to better meet the pavement performance requirements of high-grade asphalt pavement, and has very important value for solving the damage phenomena of cracking, rutting and the like of the asphalt pavement under the conditions of natural environment and traffic load, prolonging the service life of the road, improving the integrity, smoothness and water tightness of the asphalt pavement, and improving the durability and driving comfort of the asphalt pavement. The method can efficiently and quickly prepare the polyurethane modified asphalt, shorten the development period of the modified asphalt, simplify the production process, reduce the production energy consumption, and solve the problems of easy aging of the matrix asphalt and the like.
Drawings
FIG. 1 is a synthesis process of a self-made polyurethane modifier.
FIG. 2 shows polyurethane modifiers with different hard segment contents, wherein the left side C h20% is group 1-1, right C in example 1h50% is set No. 1-9 in example 1.
FIG. 3 is a flow chart of a process for preparing polyurethane modified asphalt.
FIG. 4 is a graph showing the results of the penetration, softening point and ductility tests of polyurethane-modified asphalt.
FIG. 5 is a graph of the high temperature extension temperature of polyurethane modified asphalt.
Detailed Description
The following non-limiting examples will allow one of ordinary skill in the art to more fully understand the present invention, but are not intended to limit the invention in any way.
The mass of the hard segment of the TPU is the sum of the mass of the diisocyanato and the mass of the micromolecular diol, ChThe content of hard segment in TPU is shown in formula (1.1); the isocyanate index (r) refers to the ratio of the number of diisocyanato equivalents to the sum of the number of equivalents of oligomer diols and small molecule diols, i.e. the NCO/OH ratio, and typically r is designed to be in the range of 0.9 to 1.4, see formula (1.2). The four raw materials are selected to be bifunctional, so that NCO/OH is also in a molar ratio.
Figure BDA0003277544460000031
Figure BDA0003277544460000032
In the formula, Wi、WdAnd WgMass of MDI, BDO and PBA or PTMEG respectively; mi、MdAnd MgRelative molecular masses of MDI, BDO and PBA or PTMEG, respectively.
From equations (1.1) and (1.2) we can derive:
Figure BDA0003277544460000033
the TPU is mainly divided into polyester type TPU (PBA for soft segment structure) and polyether type TPU (PTMEG for soft segment structure) according to the soft segment structure, and in order to explore factors influencing the mechanical property of the TPU, the adjustability of the chemical structure and the mechanical property of the TPU asphalt modifier is realized. The following examples select PBA and PTMEG, each having a molecular weight of 2000, as the soft segment of the TPU, ChDesigned to be 20%, 30% and 40%, r is controlled to be 0.95, 1 and 1.05. The mass of BDO was calculated according to the formula (1.3) based on 100g of PBA or PTMEG, and the mass of BDO thus calculated was taken into the formula (1.2) to obtain the mass of MDI.
Example 1
The specific design schemes of the polyester and polyether TPU asphalt modifiers are shown in tables 1 and 2 respectively.
TABLE 1 design scheme for polyester TPU asphalt modifier
Figure BDA0003277544460000041
TABLE 2 design scheme for polyether TPU asphalt modifier
Figure BDA0003277544460000042
A preparation method of a self-made polyurethane modifier is carried out according to the design schemes in tables 1 and 2, and comprises the following specific implementation steps:
PBA or PTMEG weighed in advance is placed in a 500ml dry three-neck flask, dry nitrogen (flow rate is 20ml/min) is introduced, the rotating speed of a stirrer (model R30, Shanghai Frank' S science and technology development Co., Ltd.) is adjusted to 200rpm, and dehydration is carried out for 90min in an oil bath pan (model DF-101S, Shaanxi Taikang biological science and technology Co., Ltd.) at 110 ℃. Then, the temperature of the system is reduced to 80 ℃, MDI which is weighed and melted in an oven (model DZF-6021, manufactured by Shaoxing Meyer apparatus Co., Ltd.) at 80 ℃ is added, the temperature and the rotating speed are kept unchanged to react for 2 hours, and when the viscosity of the system is gradually increased and blue light is emitted, the preparation of the polyurethane prepolymer is successful. And then, reducing the temperature of the system to 50 ℃, adding pre-weighed BDO, increasing the rotating speed of a stirrer to 400rpm, quickly stirring for 10min, stopping stirring, pouring the synthesized polyurethane into a material tray with an inner layer coated with polytetrafluoroethylene, and putting the material tray into a 100 ℃ oven to be cured for 24h to obtain the required TPU.
In order to carry out mechanical property test, the synthesized polyurethane is poured into a mold coated with a release agent in advance, the mold is closed after gelation, the polyurethane is vulcanized for 20-30 min in a flat plate vulcanizing machine (model XLB, Qingdao third rubber machinery factory), the mold is opened, a sample wafer is taken out, the sample wafer is placed in a drying box at 100 ℃ for curing for 24h, and the performance test is carried out after standing for one week at room temperature.
(1) Hardness test
The hardness values were calculated as the arithmetic mean of 10 effective tests using a HT-6510C hardness tester manufactured by Shanghai Shuangxu electronics Co., Ltd. according to national Standard of the people's republic of China (GBT1698-2003) in which the test pieces were thin plates having smooth and flat surfaces, the dimensions thereof were 50X 50mm, and the thickness thereof was 4mm, and the test results were shown in tables 3 and 4.
(2) Impact test
The test specimens were measured as standard specimens with V-shaped notches by means of a model XJV-22 cantilever impact tester manufactured by GOTECH, Taiwan, according to national Standard of the people's republic of China (GBT 1843-2008). Pendulum energy 2.75J, and the test results were an arithmetic average of 5 specimens, and are shown in tables 3 and 4.
(3) Tensile test
An electronic universal test stretcher of model 5900 manufactured by INSTRON corporation in USA was used to measure an initial measurement length of 50mm, a test environment of 25 ℃ at room temperature and a tensile rate of 50mm/min, and an arithmetic mean of 5 samples was taken as a test result, and the test results are shown in tables 3 and 4, according to national Standard of the people's republic of China (GBT 528-.
(4) Tear test
A5900 type electronic universal test stretcher produced by INSTRON company in America is adopted, according to national Standard of the people's republic of China (GBT 529 + 2008), the test sample is determined to be a right angle type (GB530-81), the thickness is 2mm, the arithmetic mean value of 5 test samples is taken as the test result, and the test result is shown in tables 3 and 4.
TABLE 3 physical and mechanical Properties of polyester TPU
Figure BDA0003277544460000051
As can be seen from Table 3, in ChAt a certain time, the relative molecular weight of the polyester TPU gradually increases with the increase of r, and the Shore hardness, the tensile strength, the tearing strength and the 300% stress at definite elongation all show a rising trend. However, the impact strength and the elongation at break of the test piece both tended to decrease. When r is constant, the relative molecular weight of the polyester TPU is dependent on ChThe shore hardness, tensile strength, tear strength and 300% stress at definite elongation all showed an upward trend, while the impact strength and elongation at break showed a downward trend. The results show that the relative molecular mass is not a major factor affecting the mechanical properties of polyester TPUs.
TABLE 4 physical and mechanical Properties of polyether TPU
Figure BDA0003277544460000061
As can be seen from Table 4, when C ishWhen the toughness of the material is 20%, the pendulum bob passing through 2.17J of all the test pieces is not fractured. The physical and mechanical property change trends of the polyether TPU and the polyester TPU are consistent through comparison. This is due to the fact that the hard segments of both are identical in structure when C ishWhen the amount of the Thermoplastic Polyurethane (TPU) is increased, the cohesive energy of the TPU is increased, which is beneficial to improving the hard segmentThe intermolecular force of TPU is increased by the formation of the hydrogen bond between the TPU molecules, which leads to the increase of the tensile strength; the reduction of the elongation at break is caused by the reduction of the content of the soft segment of the TPU, which influences the free rotation of the molecular chain in the TPU; the increase in hardness is due to an increase in the content of polar groups such as urethane in the TPU molecule, resulting in an increase in the crosslink density.
The difference in mechanical properties between polyester and polyether based TPU is shown in table 5.
TABLE 5 comparison of the Properties of polyester and polyether TPUs
Figure BDA0003277544460000062
At ChUnder the same condition, the polyester TPU and the polyether TPU show similar change trends of physical and mechanical properties with the increase of r, namely, the tensile strength is increased, and the elongation at break is reduced. This is due to r>1, excessive isocyanate groups react with hydrogen atoms on the carbamate groups, so that the molecular chains of the TPU are slightly crosslinked. The tensile strength of the polyester TPU is better than that of the polyether TPU, because the interior of the polyester TPU contains more polar polyester polyol ester groups, the intermolecular acting force is increased, the Shore hardness, the tensile strength and the tearing strength are increased, but the ester groups are increased to a certain amount, the ordered structure of the main chain of the TPU is broken, and therefore, the impact strength and the elongation at break are reduced.
The influence of the relative molecular mass on the mechanical property of the TPU is small, and the influence of the crystallinity of the hard segment on the mechanical property of the TPU is large. The hard segment crystallinity of the polyester TPU is 49.64-67.98%, the Shore hardness is 48-95A, the tensile strength is 8.28-36.2MPa, and the tear strength is 67.2-115.6 kN.m-1The 300% stress at definite elongation is 2.71-9.15 MPa. The crystallinity of the hard segment of the polyether type TPU is 48.41-59.46%, the Shore hardness is 39-85A, the tensile strength is 5.48-22.76 MPa, and the tear strength is 20.2-52.1 kN.m-1The 300% stress at definite elongation is 0.28 to 1.51 MPa. This is due to the fact that the polyether TPU segments are more flexible and the hard segments form more and less hard than the polyester TPUThe section micro-phase structure has a large specific surface area, can effectively limit the deformation of the soft section matrix, prevents the expansion of cracks, and further improves the low-temperature deformation resistance of the soft section matrix. However, the hard segment crystallinity of polyester TPU is more excellent than that of polyether TPU, and therefore, polyester TPU has physical and mechanical properties such as hardness, tear strength, and tensile strength.
As can be seen from the results of the test of the physical and mechanical properties in tables 3 and 4, the abrasion resistance, tear resistance, and tensile and tear strength of the polyester TPU are superior to those of the polyether TPU. The swelling properties of polyester TPUs in oil, grease and water are also relatively small. However, the polyether TPU has no advantages in hydrolysis resistance, microbial degradation resistance, low temperature resistance, flexibility and the like, and therefore, when the requirements for the above properties are high, the polyether TPU is recommended to be used to perform more prominently.
In the polyester type TPU, since a large amount of polar groups (ester groups) are present in the molecular chain of the polyester polyol and more hydrogen bonds are formed between each part of the soft segment and the hard segment, intermolecular forces are increased. Meanwhile, the compatibility of the soft segment and the hard segment is increased. This is because polyester polyol contains a large amount of highly polar ester groups, which not only increases the formation of hydrogen bonds between hard segments and increases intermolecular forces, but also promotes the more uniform distribution of hard segments in soft segments, which leads to the formation of more soft segment crystals and increases the degree of physical crosslinking. On the other hand, the hard segment phase of the polyether TPU is more uniformly distributed in its soft segment phase, resulting in a lower degree of microphase separation. Thus, polyether TPUs have greater internal heat generation, dynamic properties, and low temperature resistance.
Example 2
TPU modified asphalt preparation parameter determination based on orthogonal design method and grey correlation degree
In the embodiment, reaction temperature, shearing time and shearing revolution are respectively taken as control factors, each control factor takes three levels, and L is adopted9(34) The orthogonal table, specific orthogonal experimental design scheme is shown in table 1. Determining proper preparation process parameters of TPU modified asphalt based on conventional performance test results and high temperature grading temperature of PG continuous grading. In the test, the TPU is added in an amount of 10% and the high temperature classification temperature for PG continuous classification is carried out strictly in accordance with Standard practice for continuous classification temperature and continuous classification of asphalt cements for determination of Performance Classification (PG) (ASTM D7643-10).
Table 6 orthogonal test 3 factor 3 levels
Figure BDA0003277544460000071
Figure BDA0003277544460000081
A process for the preparation of a self-made polyurethane modified base asphalt, according to the orthogonal test of table 6, comprising the steps of:
polyurethane modified asphalt was prepared using a BME 100L model laboratory shearer. Firstly, polyurethane particles (the self-made polyurethane modifier prepared by the serial numbers 2-8 in the example 1, the addition amount n percent is 10 percent) with preset mixing amount are added along the side wall of the cup and preheated to T1In the matrix asphalt of DEG C, the motor rotation speed is set to S1r/min, shear t1h. Subsequently, the temperature is raised to T2Adjusting the rotation speed to S DEG C2r/min, shear t2h. And after the shearing is stopped, pouring the prepared polyurethane modified asphalt into a prepared container to be used for testing. The flow chart of the preparation process of the polyurethane modified asphalt is shown in detail in figure 3.
And (3) performance testing:
(1) a physical blending method is adopted, the reaction temperature, the shearing time and the shearing revolution are respectively used as influencing factors, and the optimal preparation process of the TPU modified asphalt is discussed through grey correlation analysis.
(2) Through conventional performance tests, the penetration degree, the softening point, the ductility at 5 ℃ and the PG continuous high-temperature grading temperature of the TPU modified asphalt are obtained, so that the change of the physical properties of the TPU modified asphalt under different preparation process conditions is evaluated, and the test results are shown in fig. 4 and fig. 5.
(3) Performing high rheological property test on the prepared polyurethane modified asphalt, and analyzing the influence of road performance of the polyurethane modified asphalt;
(4) and (3) optimizing and perfecting the preparation method of the polyurethane modified asphalt according to the optimal test results tested in the steps (2) and (3), wherein the testing method is according to technical Specifications for road asphalt pavement construction (JTG F40-2004).
In order to ensure good fluidity of the asphalt and suitability for processing, the initial reaction temperature is selected to be 145 ℃, as can be seen from fig. 4, as the reaction temperature rises, the ductility of the TPU modified asphalt sample tends to decrease, the softening point rises first and then falls, and finally tends to be flat, and the penetration degree has no obvious change rule.
With the increase of the shearing time, the penetration and the ductility of the TPU modified asphalt sample both rise first and then fall, and the softening point rises, so that the shearing time is too short, and the effect of the modifier is not obvious; too long a shearing time can lead to too long a contact time between the hot asphalt and oxygen, thus accelerating the aging of the asphalt, and also can cause the refinement degree of the modifier to be increased, thereby having an influence on the low-temperature performance of the TPU modified asphalt. As can be seen from FIG. 5, the PG continuous high temperature grading temperature increases with the reaction temperature, increases first, then decreases, and finally tends to be stable. Through experiments, when S is found1When the ratio is 3000r/min and 5000r/min, the influence on the performance of the TPU modified asphalt sample is not obvious, and when S is2At 5000r/min, the reaction temperature will rise significantly after the TPU is incorporated, and the penetration and ductility of the modified asphalt will decrease slightly. The temperature of the asphalt is rapidly increased during high-speed shearing, and the temperature is rapidly increased due to too high shearing speed, so that the asphalt aging is accelerated.
Determination of optimal preparation process parameters:
(1) determining a reference sequence and a comparison sequence. Corresponding experimental data are extracted from three investigation factors of reaction temperature, shearing time and shearing revolution and horizontal change of the three investigation factors, and analysis indexes comprise: penetration, softening point, 5 ℃ ductility and high temperature continuous grading temperature as comparative series Xi：
Xi＝(xi(1)，xi(2)，......，xi(k)) (1)
Wherein i is 1,2, … …, m; 1, 2.
Where i is the type of the influencing factor and k is the level of the influencing factor, the variables are dimensionless using the mean value method, see equation (2), and are detailed in table 7.
TABLE 7 data dimensionless processing
Figure BDA0003277544460000091
Figure BDA0003277544460000092
X0＝(x0(1)，x0(2)，......，x0(k)) (3)
Wherein i is 1,2, … …, m; 1, 2.
With { x0As reference data {59625479 }.
(2) The absolute difference value corresponding to the data sequence of each object to be evaluated and the reference data sequence is calculated one by one according to equation (4).
Δi(k)＝|x0(k)-xi(k)| (4)
TABLE 8 Absolute Difference
Figure BDA0003277544460000093
Figure BDA0003277544460000101
(3) And (5) solving a difference sequence according to the formulas (5) and (6), and solving the maximum difference and the minimum difference of the two poles according to the difference sequence.
Figure BDA0003277544460000102
Figure BDA0003277544460000103
Wherein i is 1,2, … …, m; k is 1,2, … …, n.
(4) The correlation coefficient and the degree of correlation were obtained according to equations (7) and (8), as shown in table 9.
Correlation coefficient
Figure BDA0003277544460000104
Where ρ is 0.5, i is 1,2, … …, m; k is 1,2, … …, n.
Degree of association
Figure BDA0003277544460000105
Wherein i is 1,2, … …, m.
TABLE 9 correlation coefficient and correlation degree
Figure BDA0003277544460000106
(5) And (3) sorting the relevance: gamma ray2>γ3>γ9>γ6>γ4>γ1>γ7>γ8>γ5。
In summary, the correlation degree of No. 2 is the largest, and with reference to table 6, the determined optimal preparation process parameters are: t is1And T2Respectively at 145 ℃ and 150 ℃; t is t1And t21h and 0.5h respectively; s1And S2Are 3000r/min and 3000r/min respectively.
It will be apparent to those skilled in the art from this disclosure that many changes and modifications can be made, or equivalents modified, in the embodiments of the invention without departing from the scope of the invention. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention shall still fall within the protection scope of the technical solution of the present invention, unless the contents of the technical solution of the present invention are departed.

Claims (4)

1. The preparation method of the self-made polyurethane modified matrix asphalt is characterized by comprising the following steps:
(1) preparation of self-made polyurethane modifier
Dehydrating polybutylene adipate polyester glycol or polytetramethylene ether glycol for 60-90 min at the temperature of 100-110 ℃ and the rpm of 200-500 under the condition of nitrogen; then, reducing the temperature of the system to 70-80 ℃, adding the melted 4,4' -diphenylmethane diisocyanate, keeping the temperature and the rotating speed unchanged, and reacting for 1-2 hours, wherein the polyurethane prepolymer is successfully prepared; reducing the temperature of the system to 50 ℃, adding 1, 4-butanediol, increasing the rotating speed to 300-400 rpm, stirring for 2-10 min, stopping stirring, and curing in an oven at 100-120 ℃ for 24h to obtain the required self-made polyurethane;
the polyurethane modifier comprises, by weight, 47-100 parts of polybutylene adipate polyester glycol, 48-100 parts of polytetramethylene ether glycol, 21.39-22.59 parts of 4,4' -diphenylmethane diisocyanate and 3.67-13.67 parts of 1, 4-butanediol;
(2) preparation of polyurethane modified asphalt
Adding the self-made polyurethane modifier into the mixture preheated to T1In the matrix asphalt, a shearing machine is adopted, and the rotating speed is S DEG C1Shearing t under the condition of r/min1h; subsequently, the temperature is raised to T2Adjusting the rotation speed to S DEG C2r/min, shear t2h; after the shearing is stopped, preparing the polyurethane modified asphalt;
the raw materials for preparing the polyurethane modified asphalt comprise the following components in parts by weight: 1-7 parts of self-made polyurethane modifier and 85-100 parts of matrix asphalt;
T1145 to 165, T2150 to 170, S13000 to 5000, S23000 to 5000, t10.5 to 1, t20.5 to 1.
2. The method for preparing homemade polyurethane modified base asphalt as claimed in claim 1, wherein the molecular weight of the polybutylene adipate polyester glycol or the polytetramethyl ether glycol is 1000-2000-.
3. The method for preparing the self-made polyurethane modified base asphalt according to claim 1, wherein S is S1And S2The same or different.
4. The method for preparing the homemade polyurethane modified base asphalt according to claim 1, wherein the base asphalt is rock asphalt.
CN202111121902.7A 2021-09-24 2021-09-24 Preparation method of self-made polyurethane modified asphalt Pending CN113773661A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115651540A (en) * 2022-10-19 2023-01-31 中油佳汇(广东)防水股份有限公司 Waterborne polyurethane modified emulsified asphalt and preparation method and application thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
XIN JIN ET AL.: ""Influence on Polyurethane Synthesis Parameters Upon the Performance of Base Asphalt"", 《FRONTIERS IN MATERIALS》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115651540A (en) * 2022-10-19 2023-01-31 中油佳汇(广东)防水股份有限公司 Waterborne polyurethane modified emulsified asphalt and preparation method and application thereof
CN115651540B (en) * 2022-10-19 2024-03-29 中油佳汇(广东)防水股份有限公司 Waterborne polyurethane modified emulsified asphalt and preparation method and application thereof

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