Comprehensive effect of the mechanical properties, laminated structure and healing conditions on the self-healing behaviors of laminated Al2O3-MgO ceramic composites

Cementitious structures have prevailed worldwide and are expected to exhibit further growth in the future. Nevertheless, cement cracking is an issue that needs to be addressed in order to enhance structure durability and sustainability especially when exposed to aggressive environments. The purpose of this work was to examine the impact of the Superabsorbent Polymers (SAPs) incorporation into cementitious composite materials (mortars) with respect to their structure (hybrid structure consisting of organic core—inorganic shell) and evaluate the microstructure and self-healing properties of the obtained mortars. The applied SAPs were tailored to maintain their functionality in the cementitious environment. Control and mortar/SAPs specimens with two different SAPs concentrations (1 and 2% bwoc) were molded and their mechanical properties were determined according to EN 196-1, while their microstructure and self-healing behavior were evaluated via microCT. Compressive strength, a key property for mortars, which often degrades with SAPs incorporation, in this work, practically remained intact for all specimens. This is coherent with the porosity reduction and the narrower range of pore size distribution for the mortar/SAPs specimens as determined via microCT. Moreover, the self-healing behavior of mortar-SAPs specimens was enhanced up to 60% compared to control specimens. Conclusively, the overall SAPs functionality in cementitious-based materials was optimized.

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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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Study on the Effects of the Self-Healing Microcapsules on the Tensile Properties of Polymer Composite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.299-300.460 ◽

2011 ◽

Vol 299-300 ◽

pp. 460-465 ◽

Cited By ~ 3

Author(s):

Li Zhang ◽

Xiu Ping Dong ◽

Hao Chen

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Elastic Modulus ◽

Glass Fiber ◽

Tensile Properties ◽

Polymer Composite ◽

Tensile Tests ◽

The Self ◽

Self Healing ◽

Glass Fiber Reinforced

By designing different formulations of composites and adopting optimized technology including extrusion and molding, the different composites with various content microcapsules were prepared. The results of the tensile tests show that with the increasing content of self-healing microcapsules in the glass fiber reinforced nylon composites, the mechanical properties of the composites will change, i.e. tensile strength, elastic modulus will decrease. But there is little effect on the mechanical properties of the composite gears if the content of self-healing microcapsules is less than 3.5%, and the technology of self-healing microcapsules used in the polymer composite gear is feasible.

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The Versatility of Polymeric Materials as Self-Healing Agents for Various Types of Applications: A Review

Polymers ◽

10.3390/polym13081194 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1194

Author(s):

Nik Nur Farisha Nik Md Noordin Kahar ◽

Azlin Fazlina Osman ◽

Eid Alosime ◽

Najihah Arsat ◽

Nurul Aida Mohammad Azman ◽

...

Keyword(s):

Mechanical Properties ◽

Polymer Matrix ◽

Molecular Interaction ◽

Polymeric Materials ◽

The Self ◽

Self Healing ◽

Vascular Networks ◽

Intrinsic Mechanism ◽

Different Types ◽

External Stimuli

The versatility of polymeric materials as healing agents to prevent any structure failure and their ability to restore their initial mechanical properties has attracted interest from many researchers. Various applications of the self-healing polymeric materials are explored in this paper. The mechanism of self-healing, which includes the extrinsic and intrinsic approaches for each of the applications, is examined. The extrinsic mechanism involves the introduction of external healing agents such as microcapsules and vascular networks into the system. Meanwhile, the intrinsic mechanism refers to the inherent reversibility of the molecular interaction of the polymer matrix, which is triggered by the external stimuli. Both self-healing mechanisms have shown a significant impact on the cracked properties of the damaged sites. This paper also presents the different types of self-healing polymeric materials applied in various applications, which include electronics, coating, aerospace, medicals, and construction fields. It is expected that this review gives a significantly broader idea of self-healing polymeric materials and their healing mechanisms in various types of applications.

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Surface modified halloysite nanotube enhanced imine-based epoxy composites with high self-healing efficiency and excellent mechanical properties

Polymer Chemistry ◽

10.1039/d1py00715g ◽

2021 ◽

Vol 12 (37) ◽

pp. 5342-5356

Author(s):

Hao Jiang ◽

Meng Cheng ◽

Caijiao Ai ◽

Fanjie Meng ◽

Yizeng Mou ◽

...

Keyword(s):

Molecular Structure ◽

Mechanical Properties ◽

The Self ◽

Epoxy Composites ◽

Cross Linking ◽

Schematic Diagram ◽

Self Healing ◽

Halloysite Nanotube ◽

Healing Efficiency ◽

Surface Modified

(a) Schematic diagram of the self-healing mechanism. (b) Illustration of the cross-linking effect and the internal molecular structure.

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Self-Healing UV Curable Acrylate Coatings for Wood Finishing System, Part 1: Impact of the Formulation on Self-Healing Efficiency

Coatings ◽

10.3390/coatings10080770 ◽

2020 ◽

Vol 10 (8) ◽

pp. 770

Author(s):

Chloé Paquet ◽

Thomas Schmitt ◽

Jolanta E. Klemberg-Sapieha ◽

Jean-François Morin ◽

Véronic Landry

Keyword(s):

Mechanical Properties ◽

Scratch Resistance ◽

The Self ◽

Cross Linking ◽

Hydroxyl Groups ◽

Self Healing ◽

Hydrogen Binding ◽

Uv Curable ◽

Wood Flooring ◽

Healing Property

In the wood flooring sector, good surface mechanical properties, such as abrasion and scratch resistance, are prerequisite. Surface wood protection is provided by finishing systems. Despite coating improvement, scratches formation on wood flooring is unavoidable. A new approach to increase service life is to confer the self-healing property to the finishing system. The most common coatings used for prefinished wood flooring are acrylate UV curable 100% solids coatings. They usually have good mechanical properties and high cross-linking density. The objective of this study was to develop and evaluate an intrinsic self-healing formulation, which is applicable to wood flooring. For this purpose, acrylate formulations were developed with monomers and oligomers carrying hydroxyl groups. To meet the requirements of wood application, hardness, and polymerization conversion of coatings were evaluated. König pendulum damping tests provide information on coating hardness and flexibility. Results around 80 oscillations is acceptable for UV curable wood sealer. The chemical composition was studied by FT-IR spectroscopy while dynamical mechanical analysis (DMA) was performed to determine glass transition temperature and cross-linking density. The self-healing behavior was evaluated by gloss and scratch depth measurements. The formulation’s composition impacted the hydrogen binding quantity, the conversion, the Tg and the cross-linking density. The (hydroxyethyl)methacrylate (HEMA) monomer provided self-healing and acrylated allophanate oligomer allowed self-healing and cross-linking. This study demonstrated that it is possible to combine high cross-linking density and self-healing property, using components with low steric hindrance.

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Maleimide Self-Reaction in Furan/Maleimide-Based Reversibly Crosslinked Polyketones: Processing Limitation or Potential Advantage?

Molecules ◽

10.3390/molecules26082230 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2230

Author(s):

Felipe Orozco ◽

Zafarjon Niyazov ◽

Timon Garnier ◽

Nicola Migliore ◽

Alexander Zdvizhkov ◽

...

Keyword(s):

Mechanical Properties ◽

Polymer System ◽

Side Reaction ◽

The Self ◽

The Other ◽

Side Reactions ◽

Thermal Treatments ◽

Self Healing ◽

Do So

Polymers crosslinked via furan/maleimide thermo-reversible chemistry have been extensively explored as reprocessable and self-healing thermosets and elastomers. For such applications, it is important that the thermo-reversible features are reproducible after many reprocessing and healing cycles. Therefore, side reactions are undesirable. However, we have noticed irreversible changes in the mechanical properties of such materials when exposing them to temperatures around 150 °C. In this work, we study whether these changes are due to the self-reaction of maleimide moieties that may take place at this rather low temperature. In order to do so, we prepared a furan-grafted polyketone crosslinked with the commonly used aromatic bismaleimide (1,1′-(methylenedi-4,1-phenylene)bismaleimide), and exposed it to isothermal treatments at 150 °C. The changes in the chemistry and thermo-mechanical properties were mainly studied by infrared spectroscopy, 1H-NMR, and rheology. Our results indicate that maleimide self-reaction does take place in the studied polymer system. This finding comes along with limitations over the reprocessing and self-healing procedures for furan/maleimide-based reversibly crosslinked polymers that present their softening (decrosslinking) point at relatively high temperatures. On the other hand, the side reaction can also be used to tune the properties of such polymer products via in situ thermal treatments.

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Improvement of Mechanical and Self-Healing Properties for Polymethacrylate Derivatives Containing Maleimide Modified Graphene Oxide

Polymers ◽

10.3390/polym12030603 ◽

2020 ◽

Vol 12 (3) ◽

pp. 603 ◽

Cited By ~ 1

Author(s):

Won-Ji Lee ◽

Sang-Ho Cha

Keyword(s):

Mechanical Properties ◽

Graphene Oxide ◽

Alder Reaction ◽

Diels Alder ◽

The Self ◽

Self Healing ◽

Diels Alder Reaction ◽

Healing Efficiency ◽

Modified Graphene Oxide ◽

Modified Graphene

In this paper, a self-healable nanocomposite based on the Diels-Alder reaction is developed. A graphene-based nanofiller is introduced to improve the self-healing efficiency, as well as the mechanical properties of the nanocomposite. Graphene oxide (GO) is modified with maleimide functional groups, and the maleimide-modified GO (mGO) enhanced the compatibility of the polymer matrix and nanofiller. The tensile strength of the nanocomposite containing 0.030 wt% mGO is improved by 172%, compared to that of a polymer film incorporating both furan-functionalized polymer and bismaleimide without any nanofiller. Moreover, maleimide groups of the surface on mGO participate in the Diels-Alder reaction, which improves the self-healing efficiency. The mechanical and self-healing properties are significantly improved by using a small amount of mGO.

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Study on Effects of the Nano Reinforcing Material on the Mechanical Properties of Self-Healing Composites

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.487.20 ◽

2014 ◽

Vol 487 ◽

pp. 20-24

Author(s):

Yan Miao Ma ◽

Li Zhang ◽

Guang Yuan Nie

Keyword(s):

Mechanical Properties ◽

Composite Material ◽

Impact Strength ◽

The Self ◽

Self Healing ◽

Bending Property ◽

Maximum Value ◽

Glass Fiber Reinforced ◽

Improvement Effect ◽

Reinforcing Material

In order to improve the mechanical properties of the glass fiber reinforced nylon 6 composites (GFRPP6/MCES) with microcapsules, different ratios of nanoreinforcing materials are added into this self-healing composite material which is used in gears, and how the nanoreinforcing material affects the mechanical properties of the self-healing composite is studied by testing its tensile property, bending property, impact strength and hardness. The results show that the appropriate amount of nanoreinforcing material can improve the mechanical properties of the self-healing composite. Whats more, when its content comes to 4wt%, the mechanical properties reached the maximum value and the improvement effect is the most obvious.

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Dynamic Covalent Bonds of Si-OR and Si-OSi Enabled A Stiff Polymer to Heal and Recycle at Room Temperature

Materials ◽

10.3390/ma14102680 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2680

Author(s):

Ping Fan ◽

Can Xue ◽

Xiantai Zhou ◽

Zujin Yang ◽

Hongbing Ji

Keyword(s):

Mechanical Properties ◽

Small Molecule ◽

Potential Application ◽

Room Temperature ◽

The Self ◽

Self Healing ◽

Bending Properties ◽

Covalent Bonds ◽

Model Experiments ◽

Molecule Model

As stiff polymers are difficult to self-heal, the balance between polymers’ self-healing ability and mechanical properties is always a big challenge. Herein, we have developed a novel healable stiff polymer based on the Si-OR and Si-OSi dynamic covalent bonds. The self-healing mechanism was tested and proved by the small molecule model experiments and the contrast experiments of polymers. This polymer possesses excellent tensile, bending properties as well as room temperature self-healing abilities. Moreover, due to the sticky and shapeable properties under wetting conditions, the polymer could be used as an adhesive. Besides, even after four cycles of recycling, the polymer maintains its original properties, which meets the requirements of recyclable materials. It was demonstrated that the polymer exhibits potential application in some fields, such as recyclable materials and healable adhesives.

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