Smart Self-Healing Capability of Asphalt Material Using Bionic Microvascular Containing Oily Rejuvenator

It has become one of the research directions of intelligent materials for self-healing asphalt pavements to use a bionic microvascular containing oily rejuvenator. The rejuvenator in a microvascular can carry out the healing of asphalt micro-cracks, thus reducing the damage to and prolonging the life of asphalt pavement. The aim of this work was to investigate the smart self-healing capability of an asphalt/microvascular material through its microstructure and mechanical properties. Microstructure observation indicated no interface separation between the microvasculars and bitumen matrix. Micro-CT images showed that microvasculars dispersed in asphalt samples without accumulation or tangles. The phenomenon of microcracks healing without intervention was observed, which proved that the fractured asphalt sample carried out the self-healing process with the help of rejuvenator diffusing out from the broken microvasculars. The self-healing efficiency of asphalt samples was also evaluated through a tensile test considering the factors of microvasculars content, healing time and healing temperature. It was found that the tensile strength of the asphalt samples was greatly enhanced by the addition of microvasculars under a set test condition. Self-healing efficiency was enhanced with more broken microvasculars in the rupture interface of the asphalt sample. During two self-healing cycles, the self-healing efficiency of the asphalt sample with three microvascular per 1 cm2 of a broken interface were able to reach 80% and 86%. This proves that microvasculars containing rejuvenator play a practical role in the self-healing process of asphalt. With an increase in temperature from 0 to 30 °C, the self-healing capability of the asphalt samples increased dramatically. An increase in time increased the self-healing capability of the bitumen samples. At last, a preliminary mathematical model also deduced that the self-healing efficiency was determined by the individual healing steps, including release, penetration and diffusion of the rejuvenator agent.

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Self-Healable Supramolecular Vanadium Pentoxide Reinforced Polydimethylsiloxane-Graft-Polyurethane Composites

Polymers ◽

10.3390/polym11010041 ◽

2018 ◽

Vol 11 (1) ◽

pp. 41 ◽

Cited By ~ 4

Author(s):

Ali Berkem ◽

Ahmet Capoglu ◽

Turgut Nugay ◽

Erol Sancaktar ◽

Ilke Anac

Keyword(s):

Tensile Strength ◽

Vanadium Pentoxide ◽

Coupling Reaction ◽

Optical Microscope ◽

Mechanical Tests ◽

Healing Time ◽

The Self ◽

Supramolecular Polymer ◽

Self Healing ◽

Healing Efficiency

The self-healing ability can be imparted to the polymers by different mechanisms. In this study, self-healing polydimethylsiloxane-graft-polyurethane (PDMS-g-PUR)/Vanadium pentoxide (V2O5) nanofiber supramolecular polymer composites based on a reversible hydrogen bonding mechanism are prepared. V2O5 nanofibers are synthesized via colloidal route and characterized by XRD, SEM, EDX, and TEM techniques. In order to prepare PDMS-g-PUR, linear aliphatic PUR having one –COOH functional group (PUR-COOH) is synthesized and grafted onto aminopropyl functionalized PDMS by EDC/HCl coupling reaction. PUR-COOH and PDMS-g-PUR are characterized by 1H NMR, FTIR. PDMS-g-PUR/V2O5 nanofiber composites are prepared and characterized by DSC/TGA, FTIR, and tensile tests. The self-healing ability of PDMS-graft-PUR and composites are determined by mechanical tests and optical microscope. Tensile strength data obtained from mechanical tests show that healing efficiencies of PDMS-g-PUR increase with healing time and reach 85.4 ± 1.2 % after waiting 120 min at 50 °C. The addition of V2O5 nanofibers enhances the mechanical properties and healing efficiency of the PDMS-g-PUR. An increase of healing efficiency and max tensile strength from 85.4 ± 1.2% to 95.3 ± 0.4% and 113.08 ± 5.24 kPa to 1443.40 ± 8.96 kPa is observed after the addition of 10 wt % V2O5 nanofiber into the polymer.

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The Self-Healing Performance of Carbon-Based Nanomaterials Modified Asphalt Binders Based on Molecular Dynamics Simulations

Frontiers in Materials ◽

10.3389/fmats.2020.599551 ◽

2021 ◽

Vol 7 ◽

Author(s):

Yan Gong ◽

Jian Xu ◽

Er-hu Yan ◽

Jun-hua Cai

Keyword(s):

Healing Process ◽

Asphalt Binder ◽

Mean Square Displacement ◽

The Self ◽

Asphalt Binders ◽

Self Healing ◽

Modified Asphalt ◽

Healing Efficiency ◽

Carbon Based Nanomaterials ◽

Carbon Based

In this study, the molecular dynamics simulation was used to explore the effects of carbon-based nanomaterials as binder modifiers on self-healing capability of asphalt binder and to investigate the microscopic self-healing process of modified asphalt binders under different temperature. An asphalt average molecular structure model of PEN70 asphalt binder was constructed firstly. Further, three kinds of carbon-based nanomaterials were added at three different percentages ranging from 0.5 to 1.5% to the base binder to study their effects on the self-healing capability, including two carbon nanotubes (CNT1 and CNT2) and graphene nanoflakes. Combining with the three-dimensional (3D) microcrack model to simulate the asphalt self-healing process, the density analysis, relative concentration analysis along OZ direction, and mean square displacement analysis were performed to investigate the temperature sensitive self-healing characters. Results showed that the additions of CNTs were effective in enhancing the self-healing efficiency of the plain asphalt binder. By adding 0.5% CNT1 and 0.5% CNT2, about 652% and 230% of the mean square displacement of plain asphalt binder were enhanced at the optimal temperatures. However, the use of graphene nanoflakes as an asphalt modifier did not provide any noticeable changes on the self-healing efficiency. It can be found that the self-healing capability of the asphalt was closely related to the temperature. For base asphalt, the self-healing effect became especially high at the phase transition temperature range, while, for the modified asphalt, the enhancement of the self-healing capability at the low phase transition temperature (15°C) became negligible. In general, the optimal healing temperature range of the CNTs modified asphalt binders is determined as 45–55°C and the optimal dosage of the CNTs is about 0.5% over the total weight of the asphalt binder. Considering the effect of carbon-based nanomaterials on the self-healing properties, the recommended carbon-based nanomaterials modifier is CNT1 with the aspect ratio of 1.81.

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Microencapsulated Bio-Based Rejuvenators for the Self-Healing of Bituminous Materials

Materials ◽

10.3390/ma13061446 ◽

2020 ◽

Vol 13 (6) ◽

pp. 1446 ◽

Cited By ~ 6

Author(s):

Jose Norambuena-Contreras ◽

Luis E. Arteaga-Perez ◽

Andrea Y. Guadarrama-Lezama ◽

Rodrigo Briones ◽

Juan F. Vivanco ◽

...

Keyword(s):

Thermal Stability ◽

Chemical Properties ◽

The Self ◽

Asphalt Pavements ◽

Self Healing ◽

Biomass Waste ◽

Good Thermal Stability ◽

Bituminous Materials ◽

Healing Efficiency ◽

Indentation Tests

Asphalt self-healing by encapsulated rejuvenating agents is considered a revolutionary technology for the autonomic crack-healing of aged asphalt pavements. This paper aims to explore the use of Bio-Oil (BO) obtained from liquefied agricultural biomass waste as a bio-based encapsulated rejuvenating agent for self-healing of bituminous materials. Novel BO capsules were synthesized using two simple dripping methods through dropping funnel and syringe pump devices, where the BO agent was microencapsulated by external ionic gelation in a biopolymer matrix of sodium alginate. Size, surface aspect, and elemental composition of the BO capsules were characterized by optical and scanning electron microscopy and energy-dispersive X-ray spectroscopy. Thermal stability and chemical properties of BO capsules and their components were assessed through thermogravimetric analysis (TGA-DTG) and Fourier-Transform Infrared spectroscopy (FTIR-ATR). The mechanical behavior of the capsules was evaluated by compressive and low-load micro-indentation tests. The self-healing efficiency over time of BO as a rejuvenating agent in cracked bitumen samples was quantified by fluorescence microscopy. Main results showed that the BO capsules presented an adequate morphology for the asphalt self-healing application, with good thermal stability and physical-chemical properties. It was also proven that the BO can diffuse in the bitumen reducing the viscosity and consequently self-healing the open microcracks.

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Detailed Analysis of the Influencing Parameters on the Self-Healing Behavior of Dynamic Urea-Crosslinked Poly(methacrylate)s

Molecules ◽

10.3390/molecules24193597 ◽

2019 ◽

Vol 24 (19) ◽

pp. 3597 ◽

Cited By ~ 2

Author(s):

Abend ◽

Zechel ◽

Schubert ◽

Hager

Keyword(s):

Detailed Analysis ◽

Mechanical Performance ◽

Healing Process ◽

Polymer Networks ◽

Healing Time ◽

The Self ◽

Self Healing ◽

Influencing Parameters ◽

The Impact

For this paper, the self-healing ability of poly(methacrylate)s crosslinked via reversible urea bonds was studied in detail. In this context, the effects of healing time and temperature on the healing process were investigated. Furthermore, the impact of the size of the damage (i.e., area of the scratch) was monitored. Aging processes, counteracting the self-healing process, result in a decrease in the mechanical performance. This effect diminishes the healing ability. Consequently, the current study is a first approach towards a detailed analysis of self-healing polymers regarding the influencing parameters of the healing process, considering also possible aging processes for thermo-reversible polymer networks.

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Preparation and Properties of Self-Healing Waterborne Polyurethane Based on Dynamic Disulfide Bond

Polymers ◽

10.3390/polym13172936 ◽

2021 ◽

Vol 13 (17) ◽

pp. 2936

Author(s):

Gongbo Ye ◽

Tao Jiang

Keyword(s):

Particle Size ◽

Tensile Strength ◽

Healing Process ◽

Waterborne Polyurethane ◽

The Self ◽

Polymer Materials ◽

Self Healing ◽

Heat Treated ◽

Healing Efficiency ◽

Excellent Stability

A self-healing waterborne polyurethane (WPU) materials containing dynamic disulfide (SS) bond was prepared by introducing SS bond into polymer materials. The zeta potential revealed that all the synthesized WPU emulsions displayed excellent stability, and the particle size of them was about 100 nm. The characteristic peaks of N-H and S-S in urethane were verified by FTIR, and the chemical environment of all elements were confirmed by the XPS test. Furthermore, the tensile strength, self-healing process and self-healing efficiency of the materials were quantitatively evaluated by tensile measurements. The results showed that the self-healing efficiency could reach 96.14% when the sample was heat treated at 70 °C for 4 h. In addition, the material also showed a good reprocessing performance, and the tensile strength of the reprocessed film was 3.39 MPa.

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The effect of healing time on the self-healing efficiency of carbon fibre reinforced polymer composites

Materials Today Proceedings ◽

10.1016/j.matpr.2017.02.171 ◽

2017 ◽

Vol 4 (2) ◽

pp. 2903-2909 ◽

Cited By ~ 2

Author(s):

Saurabh Saini ◽

Deepak Jain

Keyword(s):

Carbon Fibre ◽

Polymer Composites ◽

Healing Time ◽

The Self ◽

Self Healing ◽

Reinforced Polymer ◽

Healing Efficiency ◽

Carbon Fibre Reinforced Polymer ◽

Fibre Reinforced Polymer

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Sustainable High-Ductility Concrete with Rapid Self-Healing Characteristic by Adding Magnesium Oxide and Superabsorbent Polymer

Advances in Materials Science and Engineering ◽

10.1155/2020/5395602 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Shuyin Wu ◽

Guoyang Lu ◽

Quan Liu ◽

Pengfei Liu ◽

Jun Yang

Keyword(s):

Magnesium Oxide ◽

Healing Time ◽

The Self ◽

Uniaxial Tensile ◽

Uniaxial Tensile Test ◽

Superabsorbent Polymer ◽

Self Healing ◽

High Ductility ◽

Healing Property ◽

The Individual

As a class of high-ductility concrete, engineered cementitious composites (ECC) have wide application prospects in engineering fields. However, the occurrence of cracks and the limited self-healing ability hinder the development of ECC. Rapid self-healing has important significance for ECC in reducing maintenance costs and prolonging service life, which are conducive to sustainable development of ECC. Therefore, the aim of this paper is to enhance the self-healing property of ECC by adding light-burned magnesium oxide (MgO) and superabsorbent polymer (SAP) on the premise of maintaining the high ductility. First, the effect of MgO and SAP on the ductility property of ECC which is the most important feature was explored with the uniaxial tensile test. The results indicated that MgO is helpful to the strength but not conducive to the ductility of ECC, while SAP has an opposite effect. The effects of MgO and SAP on the ductility of ECC can be balanced. Later, the permeability test, scanning electron microscopy (SEM), and X-ray diffraction (XRD) were used to evaluate the effects of MgO and SAP on the self-healing property of ECC. The results showed that the combined addition of MgO and SAP shows much better effect than the individual addition and can cut the healing time by half. Overall, it is concluded that ECC with MgO and SAP have the potential for self-healing, and the ductility can also be reconciled.

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Continuum damage-healing framework for the hydration induced self-healing of the cementitious composite

International Journal of Damage Mechanics ◽

10.1177/1056789520968037 ◽

2020 ◽

pp. 105678952096803

Author(s):

Qing Chen ◽

Xiangyong Liu ◽

Hehua Zhu ◽

J Woody Ju ◽

Xie Yongjian ◽

...

Keyword(s):

Healing Process ◽

Healing Time ◽

Continuum Damage ◽

Self Healing ◽

Hydration Products ◽

Cementitious Composite ◽

Hydration Kinetics ◽

Micro Cracks ◽

Damage Healing ◽

Healing Model

The self-healing materials have become more and more popular due to their active capacity of repairing the (micro-) damages, such as the (micro-) cracks, the (micro-) voids and the other defects. In this paper, the thermodynamic based damage-healing framework is presented for the hydration induced self-healing composite with a compatible healing variable. The new variable is incorporated to consider the time-dependent properties of the hydration products, with which a new damage healing law is proposed. The hydration kinetics are employed to describe the healing process. The properties of the hydration products are arrived with the multiscale and multilevel homogenization scheme. The presented damage-healing model is applied to an isotropic cementitious composite under the tensile loading histories. The presented framework is compared with the classic continuum damage-healing theory and the experimental data. The results show that the presented damage-healing model is capable of describing the hydration induced self-healing of the cementitious composite. It can describe the behavior of the partially and fully healed concrete material. The effects of the healing time and the compatible healing variables on the damage-healing results are investigated based on our proposed framework.

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