Self-healable soft shield for γ-ray radiation based on polyacrylamide hydrogel composites

AbstractWith the growing risk of radiation exposure, there are growing interests in radiation shielding. Because most radiation shields are made from heavy metals, a need to develop a soft shield is raised to protect human body. However, because the shield can easily undergo a mechanical damage by an impact, it would be better to have self-repairing system in the shield. Here, we have fabricated an intrinsic self-healable soft shield for gamma ray by making acrylamide based hydrogel composite. The composite contains lead dioxide nanoparticles for gamma ray shielding and Laponite clays for self-repairing. Although the hydrogel contained a large amount of lead dioxide nanoparticles (3.23 M), the fabricated composites stretched beyond 1400% while showing a high attenuation coefficient of 0.1343 cm−1 against gamma ray from a cobalt-60 source. Then a systematic study was performed to analyze self-healing properties and the 96.55% of maximum self-healing efficiency was obtained. We also analyzed a storage modulus of hydrogel and molecular weight of polyacrylamide to study an effect of gamma ray on the self-healing. The self-healing efficiency was decreased by a gamma ray because the radiation induces scissioning or covalent crosslinking in the chains.

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Self-healing polymer/carbon nanotube nanocomposite: A review

Journal of Plastic Film & Sheeting ◽

10.1177/8756087920960195 ◽

2020 ◽

pp. 875608792096019

Author(s):

Ayesha Kausar

Keyword(s):

Drug Delivery ◽

Tissue Engineering ◽

Carbon Nanotube ◽

Radiation Shielding ◽

The Self ◽

Self Healing ◽

Processing Strategies ◽

Healing Efficiency ◽

Matrix Modification ◽

Critical Issues

Self-healing polymers have the capability to autonomically heal themselves. Recent breakthroughs in self-healing systems rely on integrating nanoparticles into relevant polymers. This article overviews the self-healing performance of polymer/carbon nanotube nanocomposite. Self-healing carbon nanotube nanocomposites have been designed using epoxy, polyurethane, poly(methyl methacrylate), and rubbers. Great versatility of self-healed polymer/carbon nanotube depends on matrix modification, nanotube functionality, processing strategies, and matrix-nanofiller interaction/compatibility. Special consideration is given to self-healing efficiency of nanocomposites in technical fields, such as coatings, sensors, electronics, radiation shielding, drug delivery, and tissue engineering. Moreover, critical issues and challenges associated with self-healing nanocomposites are considered.

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Effect of Using Magnesium Acetate on the Self-Healing Efficiency of Hydrogel-Encapsulated Bacteria in Concrete

10.1061/9780784483787.018 ◽

2021 ◽

Author(s):

Ricardo Hungria ◽

Momen Mousa ◽

Marwa Hassan ◽

Omar Omar ◽

Andrea Gavilanes ◽

...

Keyword(s):

The Self ◽

Magnesium Acetate ◽

Self Healing ◽

Healing Efficiency ◽

Encapsulated Bacteria

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Design of self-healing catalysts for aircraft application

International Journal of Structural Integrity ◽

10.1108/ijsi-12-2017-0077 ◽

2018 ◽

Vol 9 (6) ◽

pp. 723-736 ◽

Cited By ~ 1

Author(s):

Elisa Calabrese ◽

Pasquale Longo ◽

Carlo Naddeo ◽

Annaluisa Mariconda ◽

Luigi Vertuccio ◽

...

Keyword(s):

Ruthenium Catalysts ◽

The Self ◽

Self Healing ◽

Catalytic Systems ◽

Content Type ◽

Aerospace Applications ◽

Healing Efficiency ◽

Relevant Role ◽

Aircraft Application

PurposeThe purpose of this paper is to highlight the relevant role of the stereochemistry of two Ruthenium catalysts on the self-healing efficiency of aeronautical resins.Design/methodology/approachHere, a very detailed evaluation on the stereochemistry of two new ruthenium catalysts evidences the crucial role of the spatial orientation of phenyl groups in the N-heterocyclic carbene ligands in determining the temperature range within the curing cycles is feasible without deactivating the self-healing mechanisms (ring-opening metathesis polymerization reactions) inside the thermosetting resin. The exceptional activity and thermal stability of the HG2MesPhSyncatalyst, with the syn orientation of phenyl groups, highlight the relevant potentiality and the future perspectives of this complex for the activation of the self-healing function in aeronautical resins.FindingsThe HG2MesPhSyncomplex, with the syn orientation of the phenyl groups, is able to activate metathesis reactions within the highly reactive environment of the epoxy thermosetting resins, cured up to 180°C, while the other stereoisomer, with the anti-orientation of the phenyl groups, does not preserve its catalytic activity in these conditions.Originality/valueIn this paper, a comparison between the self-healing functionality of two catalytic systems has been performed, using metathesis tests and FTIR spectroscopy. In the field of the design of catalytic systems for self-healing structural materials, a very relevant result has been found: a slight difference in the molecular stereochemistry plays a key role in the development of self-healing materials for aeronautical and aerospace applications.

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Experimental Investigation on the Self-Healing Efficiency of Araldite 2011 Adhesive Reinforced with Thermoplastic Microparticles

Adhesives - Applications and Properties ◽

10.5772/65167 ◽

2016 ◽

Cited By ~ 1

Author(s):

Halil Özer ◽

Engin Erbayrak

Keyword(s):

Experimental Investigation ◽

The Self ◽

Self Healing ◽

Healing Efficiency

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Nanoparticle-Hydrogel Composites: From Molecular Interactions to Macroscopic Behavior

Polymers ◽

10.3390/polym11020275 ◽

2019 ◽

Vol 11 (2) ◽

pp. 275 ◽

Cited By ~ 28

Author(s):

Corinna Dannert ◽

Bjørn Torger Stokke ◽

Rita S. Dias

Keyword(s):

Mechanical Properties ◽

Molecular Design ◽

The Self ◽

Self Healing ◽

Sensor Applications ◽

Composite Gels ◽

Equilibrium Swelling ◽

Hydrogel Composites ◽

Materials Used ◽

Network Component

Hydrogels are materials used in a variety of applications, ranging from tissue engineering to drug delivery. The incorporation of nanoparticles to yield composite hydrogels has gained substantial momentum over the years since these afford tailor-making and extend material mechanical properties far beyond those achievable through molecular design of the network component. Here, we review different procedures that have been used to integrate nanoparticles into hydrogels; the types of interactions acting between polymers and nanoparticles; and how these underpin the improved mechanical and optical properties of the gels, including the self-healing ability of these composite gels, as well as serving as the basis for future development. In a less explored approach, hydrogels have been used as dispersants of nanomaterials, allowing a larger exposure of the surface of the nanomaterial and thus a better performance in catalytic and sensor applications. Furthermore, the reporting capacity of integrated nanoparticles in hydrogels to assess hydrogel properties, such as equilibrium swelling and elasticity, is highlighted.

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Healing Performance of a Self-Healing Protective Coating According to Damage Width

Coatings ◽

10.3390/coatings10060543 ◽

2020 ◽

Vol 10 (6) ◽

pp. 543

Author(s):

Dong-Min Kim ◽

Junseo Lee ◽

Ju-Young Choi ◽

Seung-Won Jin ◽

Kyeong-Nam Nam ◽

...

Keyword(s):

Protective Coating ◽

Coating Thickness ◽

Chloride Ion ◽

The Self ◽

Self Healing ◽

Chloride Ion Penetration ◽

Healing Efficiency ◽

Sem Study ◽

Capsule Size ◽

Ion Penetration

Although self-healing protective coatings have been widely studied, systematic research on healing performance of the coating according to damage width has been rare. In addition, there has been rare reports of self-healing of the protective coating having damage width wider than 100 µm. In this study, self-healing performance of a microcapsule type self-healing protective coating on cement mortar was studied for the coating with damage width of 100–300 µm. The effect of capsule-loading (20 wt%, 30 wt% and 40 wt%), capsule size (65-, 102- and 135-µm-mean diameter) and coating thickness (50-, 80- and 100-µm-thick undercoating) on healing efficiency was investigated by water sorptivity test. Accelerated carbonation test, chloride ion penetration test and scanning electron microscope (SEM) study were conducted for the self-healing coating with a 300-µm-wide damage. Healing efficiency of the self-healing coating decreased with increasing damage width. As capsule-loading, capsule size or coating thickness increased, healing efficiency of the self-healing coating increased. Healing efficiency of 76% or higher was achieved using the self-healing coating with a 300-µm-wide scratch. The self-healing coating with a 200-µm-wide crack showed healing efficiency of 70% or higher. The self-healing coating having a 300-µm-wide scratch showed effective protection of the substrate mortar from carbonation and chloride ion penetration, which was supported by SEM study.

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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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Self-Healing of Concrete Cracks by Ceramsite-Loaded Microorganisms

Advances in Materials Science and Engineering ◽

10.1155/2018/5153041 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8 ◽

Cited By ~ 11

Author(s):

Jing Xu ◽

Xianzhi Wang ◽

Junqing Zuo ◽

Xiaoyan Liu

Keyword(s):

Heat Treatment ◽

Compressive Strength ◽

Heating Temperature ◽

Concrete Strength ◽

The Self ◽

Self Healing ◽

Healing Efficiency ◽

Maximum Crack ◽

Harsh Conditions ◽

Urea Decomposition

Protective carrier is essential for the self-healing of concrete cracks by microbially induced CaCO3 precipitation, owing to the harsh conditions in concrete. In this paper, porous ceramsite particles are used as microbial carrier. Heat treatment and NaOH soaking are first employed to improve the loading content of the ceramsite. The viability of bacterial spores is assessed by urea decomposition measurements. Then, the self-healing efficiency of concrete cracks by spores is evaluated by a series of tests including compressive strength regain, water uptake, and visual inspection of cracks. Results indicate that heat treatment can improve the loading content of ceramsite while not leading to a reduction of concrete strength by the ceramsite addition. The optimal heating temperature is 750°C. Ceramsite particles act as a shelter and protect spores from high-pH environment in concrete. When nutrients and spores are incorporated in ceramsite particles at the same time, nutrients are well accessible to the cells. The regain ratio of the compressive strength increases over 20%, and the water absorption ratio decreases about 30% compared with the control. The healing ratio of cracks reaches 86%, and the maximum crack width healed is near 0.3 mm.

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