English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Modified mechanism of asphalt of PPA in conjunction with SBS is studied on from the microscopic view by experiments. These experiments include four constituents,fluorescence microscopy, infrared spectroscopy and DSC. The results show that the proportion of asphaltene increase and the proportion of colloid decrease because of PPA adding. Its can promote the dissolve dissolution of SBS modifier in order to enhance the network structure of asphalt.PPA contributes to the colloidal structure of asphalt conversion from sol to sol-gel structure. That is helpful to improve high temperature performance; aging-resisting performance and storage performance of SBS modified asphalt. Introduction Poly phosphoric acid modified asphalt is a kind of acid modified asphalt what can improve high temperature performance, aging-resisting performance, increase storage stability of SBS modified asphalt and decrease project cost. It is analyzed a series of chemical and physical changes of SBS modified asphalt under the different proportion of PPA by experiments. These experiments include four constituents,fluorescence microscopy,infrared spectroscopy and DSC. That is can be evaluated modified mechanism of asphalt of PPA in conjunction with SBS. Four Constituents Four constituents analysis utilize the principle that material dissolve in alternative in different organic solvent and absorb in the alternative in different adsorbent. So the asphalt can be separated four chemical similar characteristics constituents such as asphaltene,saturated fraction,aromatic fraction and colloid. It is analyzed four constituents of asphalt by solvent sediments and chromatographic columns in this experiment. As is well known, polymer is dispersed many granules by swelling and high speed shearing when polymer is joined in asphalt. It is physical miscible process and polar of the swelling polymer is similar to colloid. It is considered that the SBS has little influence on performance of asphalt because polymer is used as part of colloid. So it is major studied on that PPA influence on each component of asphalt in this paper. The proportion of PPA is 0%,0.5%,1%,1.5% and 2% . The test results are shown in fig1. The content of asphaltene obviously increase and the content of colloid obviously decrease When the proportion of PPA increase from 0% to 2% from fig1. The content of asphaltene increase from 9.4% to 16.7% and the content of colloid decrease from 36.6% to 28.5%. The content of saturated fraction and aromatic fraction has no significant change. Changes in constituents of asphalt can affect changes of colloidal structure according to modern colloidal theories. The contents of asphaltene increases will lead to the contents of colloidal core increase. Colloidal core can absorb surrounding oil which results in the formation larger micelle. The number of micelle increase means the distance of micelle decrease and part of micelle International Conference on Materials, Environmental and Biological Engineering (MEBE 2015) © 2015. The authors Published by Atlantis Press 192 even come into contact with each other. So the viscosity of asphalt increases because the forces of between micelles increase. As the same time, the forces of between micelles increase with the volume of micelles which lead to form the intensive space network structure. That is helpful to enhance the storage stability of asphalt. PPA contributes to the colloidal structure of asphalt conversion from sol to sol-gel structure. The content of asphaltene increase and colloid decrease which lead to asphalt stiffness increase, the softening point and viscosity increase and penetration reduce. So PPA can effectively improve the high temperature performance and storage stability of asphalt. Infrared absorption spectroscopy Infrared absorption spectroscopy belongs to the category of molecular absorption spectra which is usually used to analyze chemical structure of substances. The principle is what polar molecules absorb infrared ray correspond of vibration energy levels. Parts of wavelengths radiation are absorbed into sample when the sample is irradiated by different wavelengths infrared ray. Some wavelengths of radiation are absorbed by the sample, then weaken, thus formed the infrared absorption spectrum. We can analyze group and molecule structure of the material from the position,the number,the relative intensity and the shape of absorption peak of the infrared absorption spectrum. First the asphalt is dissolved in 5 percent carbon tetrachloride solution. Then this solution is smeared on flake of potassium bromide in order to form a thin film coating. Finally we can analyze the sample which carbon tetrachloride solution is volatilized using the spotlight. We consider that the coating thickness of asphalt is not being the same on the potassium bromide[1]. It’s only comparison of the spectral curve of different samples is pointless because the different coating thickness will affect the strength of the absorption peak. So we can compare changes of different asphalt absorption peaks using the area ratio method. It is chosen the proportion of SBS is 0%,3% and 4% and the proportion of PPA is 0%,0.5%,1 %,1.5% and 2% under each SBS dosage. We can know that absorption peak of asphalt is mainly located in 1030 1 cm from spectrum of asphalt. So we calculate percentage of absorption peak area in 1030 1 cm by the sum of absorption peaks area within 600 1 cm -2000 1 cm as the reference area. It is showed by the index of s o I = and the test results are shown in Fig2. At the same time we can know that the absorption peak of SBS modified asphalt mainly located in 6965 1 cm and 97 1 cm . It is showed by indexes of C C I = and H C I − . The test results are shown in fig3 and fig4. Fig1 the relationship between different proportion of PPA and asphalt 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0

Study on Modified mechanism of asphalt of PPA in conjunction with SBS