Low-density polyethylene/silica compound modified asphalts with high-temperature storage stability

Styrene-butadiene-styrene tri-block copolymer (SBS) modified asphalts are usually unstable during high-temperature storage, which presents an obstacle to their application. In this paper, SBS modified asphalts with improved high-temperature storage stability were prepared by incorporating carbon black (CB) into the SBS compounds. The effect of CB on the high-temperature storage properties, dynamic rheology, mechanical properties (softening point, viscosity etc.) and the morphologies of the modified asphalts were studied. It was found that the ratio of SBS to CB in the compound had a great effect on the high-temperature storage behavior. The modified asphalts were stable when the ratio of SBS/CB was around 2. CB had almost no effect on the dynamic rheology or the mechanical properties of the modified asphalts. The improvement in high-temperature storage behavior could be caused by decreasing the density difference and improving the compatibility between SBS and asphalt.

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Investigation on the Short-Term Aging-Resistance of Thermoplastic Polyurethane-Modified Asphalt Binders

Polymers ◽

10.3390/polym10111189 ◽

2018 ◽

Vol 10 (11) ◽

pp. 1189 ◽

Cited By ~ 4

Author(s):

Ruien Yu ◽

Xijing Zhu ◽

Maorong Zhang ◽

Changqing Fang

Keyword(s):

Thermal Properties ◽

High Temperature ◽

High Speed ◽

Storage Stability ◽

Thermoplastic Polyurethane ◽

Short Term ◽

Modified Asphalt ◽

Aging Resistance ◽

High Temperature Storage ◽

Temperature Storage

In this reported work, thermoplastic polyurethane (TPU) was used as a reactive polymer modifying agent to prepare a modified-asphalt, using a high-speed shearing method. Physical performance tests of the TPU-modified asphalt were conducted before and after short-term aging, and the aging resistance was examined by the change in materials properties. In addition, low-temperature rheological properties, thermal properties, the high-temperature storage stability, and the aging mechanism of TPU-modified asphalt were also investigated. The results showed that the addition of TPU improved the aging resistance of base asphalt, which was evidenced by the increased penetration ratio and decreased softening point of the asphalt, after aging. Similarly, Fourier Transform infrared (FTIR) spectroscopy results verified that TPU improved the asphalt aging resistance. It was found that the TPU functional groups played a role in improving thermal properties, high-temperature storage stability, and in the dispersion of modified asphalt.

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Asphalt Modified by Ethylene-Acrylic Acid Copolymer Ionomers: Fundamental Investigations of Mechanical and Rheological Properties

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.871.371 ◽

2021 ◽

Vol 871 ◽

pp. 371-378

Author(s):

Chun Fa Ouyang ◽

Chun Ye Xu ◽

Qun Gao ◽

Wei Li Xue ◽

Wei Gang Yang ◽

...

Keyword(s):

High Temperature ◽

Acrylic Acid ◽

Storage Stability ◽

Rheological Characteristics ◽

Metal Hydroxides ◽

Modified Asphalt ◽

Acid Copolymer ◽

High Temperature Storage ◽

Acrylic Acid Copolymer ◽

Temperature Storage

Ethylene-acrylic acid copolymer (EAA) has been demonstrated to be a suitable additive for modifying the properties of asphalt. EAA mixed with metal hydroxides/oxides form EAA-M ionomers, which increase the polarity of EAA, improving its adhesive properties and affecting its mechanical and rheological characteristics. The present work investigates the mechanical and rheological characteristics of asphalt modified by EAA in conjunction with either Ca (OH)2, NaOH, or ZnO. The high-temperature properties of the modified asphalts, including the softening point, and needle penetration, were evaluated. Rheological characteristics of modified asphalts were investigated by rotary rheometer. Moreover, the storage stability at high temperature, morphology and chemical structure were also analyzed. Results indicate that a 4wt% EAA-M ionomer concentration in the base asphalt is adequate for providing the enhanced properties studied. For an equivalent concentration of EAA, the properties of modified asphalts were affected by very small additions of the metal hydroxides/oxides. The best overall mechanical and rheological performance was obtained for EAA-Ca modified asphalt with 4wt% EAA and 2.5wt‰ Ca (OH)2. EAA-Zn modified asphalt provided the most stable high-temperature storage. Compared with 6wt% pure EAA-modified asphalt, which is not stable, the EAA-Zn modified asphalt (2.7wt‰ ZnO) demonstrated reasonable high-temperature storage stability. Compared with asphalt modified with 6wt% pure EAA, the softening point increased from 55.81 °C to 58.05 °C with the addition of 2.7wt‰ NaOH. However, while the mechanical and rheological properties of EAA-Na modified asphalt were very good, its high-temperature storage stability due to the strong reactivity of NaOH, which led to the crosslinking of EAA-Na ionomers, making it difficult to disperse.

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Improved Storage Stability of LDPE/SBS Blends Modified Asphalts

Polymers and Polymer Composites ◽

10.1177/096739110201000305 ◽

2002 ◽

Vol 10 (3) ◽

pp. 229-236 ◽

Cited By ~ 5

Author(s):

Guangtao Gao ◽

Yong Zhang ◽

Yinxi Zhang ◽

Kang Sun ◽

Yongzhong Fan

Keyword(s):

High Temperature ◽

Storage Stability ◽

Optical Microscope ◽

Low Density Polyethylene ◽

Low Density ◽

High Shear ◽

High Shear Stress ◽

Styrene Butadiene Styrene ◽

Styrene Butadiene ◽

Butadiene Styrene

In this paper, Low Density Polyethylene (LDPE) / Styrene-Butadiene-Styrene (SBS) blends prepared under high shear stress were used as asphalt modifiers. Compared to the asphalts modified by LDPE and SBS added directly, the blend modified asphalts showed much better storage stability in the presence of sulfur at high temperature. No visible phase separation was observed under an optical microscope at high temperature and the morphology analysis indicated that the phase structure of the LDPE/SBS blend modified asphalts was unchanged with time at high temperature. After storage at 163°Ê for 48h, the LDPE/SBS blend modified asphalts had no evidence of coalescence of polymer particles. The rheological properties of the asphalts were also improved by the addition of polymers in all cases.

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