Recent progress in self-healing polymers and hydrogels based on reversible dynamic B–O bonds: boronic/boronate esters, borax, and benzoxaborole

Self-healing polymeric materials developed in the last decade is one of the marvels in the field of material science and polymer chemistry. Self-healing Glass Fibre Reinforced Plastics (GFRP) was fabricated with the microcapsule based self-healing system which can be triggered by the catalyst, when the capsule breaks open releasing the healing agent, during crack formation. The dynamic mechanical properties of the composite were assessed to find its dependence on temperature, stress and frequency and to report the changes in stiffness and damping. The storage modulus, loss modulus and damping factor were investigated for various frequencies and temperature and discussed.

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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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Autonomous self-healing polyisoprene elastomers with high modulus and good toughness based on the synergy of dynamic ionic crosslinks and highly disordered crystals

Polymer Chemistry ◽

10.1039/d0py01034k ◽

2020 ◽

Vol 11 (41) ◽

pp. 6549-6558

Author(s):

Yohei Miwa ◽

Mayu Yamada ◽

Yu Shinke ◽

Shoichi Kutsumizu

Keyword(s):

Mechanical Properties ◽

Room Temperature ◽

Self Healing ◽

High Modulus ◽

Disordered Crystals ◽

Ionic Crosslinks

We designed a novel polyisoprene elastomer with high mechanical properties and autonomous self-healing capability at room temperature facilitated by the coexistence of dynamic ionic crosslinks and crystalline components that slowly reassembled.

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Ultrastrong, Free-Standing and Large Nanofilms of Pyrenearamid

10.26434/chemrxiv.8182088 ◽

2019 ◽

Author(s):

Amalia Rapakousiou ◽

Alejandro López-moreno ◽

Belén Nieto-Ortega ◽

M. Mar Bernal ◽

Miguel A. Monclús ◽

...

Keyword(s):

Mechanical Properties ◽

Building Block ◽

Aromatic Polyamide ◽

Free Standing ◽

Spatial Confinement ◽

Polymeric Structure ◽

Reduced Modulus ◽

Organizational Arrangement ◽

Polycyclic Aromatic ◽

Nanoscale Building Block

We introduce poly(1,6-pyrene terephthalamide) polymer (PPyrTA) as an aromatic polyamide analogue of poly(p-phenylene terephthalamide) (PPTA), also known as Kevlar®. This work shows that the incorporation of polycyclic aromatic pyrene moieties improves drastically the mechanical properties of the polymeric structure, increasing elastic nanoindentation-determined modulus and hardness by factors of 1.9 and 4.3, respectively. Liquid deprotonated dispersions of PPyrTA nanofibers were used as nanoscale building block for producing large-surface, free-standing polymer macroscopic nanofilms. This 2D assembly leads to further significant improvements in reduced modulus and hardness (more than twice) compared to the starting polymer macroscale fibres, due to a better re-organizational arrangement of the PPyrTA nanofibers in the nanofilms, formed under 2D spatial confinement.

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Possibilities of using biodegradable polymeric materials in the agricultural sector

Elektrotekhnologii i elektrooborudovanie v APK ◽

10.22314/2658-4859-2020-67-2-115-120 ◽

2020 ◽

Vol 67 (2) ◽

pp. 115-120

Author(s):

Raisa A. Alekhina ◽

Victoriya E. Slavkina ◽

Yuliya A. Lopatina

Keyword(s):

Mechanical Properties ◽

Biodegradable Polymers ◽

Biodegradable Polymer ◽

Agricultural Sector ◽

Polymeric Materials ◽

Polymer Materials ◽

Limiting Factors ◽

Research Purpose ◽

Biodegradable Materials ◽

Advantages And Disadvantages

The article presents options for recycling polymers. The use of biodegradable materials is promising. This is a special class of polymers that can decompose under aerobic or anaerobic conditions under the action of microorganisms or enzymes forming natural products such as carbon dioxide, nitrogen, water, biomass, and inorganic salts. (Research purpose) The research purpose is in reviewing biodegradable materials that can be used for the manufacture of products used in agriculture. (Materials and methods) The study are based on open information sources containing information about biodegradable materials. Research methods are collecting, studying and comparative analysis of information. (Results and discussion) The article presents the advantages and disadvantages of biodegradable materials, mechanical properties of the main groups of biodegradable polymers. The article provides a summary list of agricultural products that can be made from biodegradable polymer materials. It was found that products from the general group are widely used in agriculture. Authors have found that products from a special group can only be made from biodegradable polymers with a controlled decomposition period in the soil, their use contributes to increasing the productivity of crops. (Conclusions) It was found that biodegradable polymer materials, along with environmental safety, have mechanical properties that allow them producing products that do not carry significant loads during operation. We have shown that the creation of responsible products (machine parts) from biodegradable polymers requires an increase in their strength properties, which is achievable by creating composites based on them. It was found that the technological complexity of their manufacture and high cost are the limiting factors for the widespread use of biodegradable polymers at this stage.

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Anti-Inflammatory Properties of Injectable Betamethasone-Loaded Tyramine-Modified Gellan Gum/Silk Fibroin Hydrogels

Biomolecules ◽

10.3390/biom10101456 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1456

Author(s):

Isabel Matos Oliveira ◽

Cristiana Gonçalves ◽

Myeong Eun Shin ◽

Sumi Lee ◽

Rui Luis Reis ◽

...

Keyword(s):

Rheumatoid Arthritis ◽

Mechanical Properties ◽

Silk Fibroin ◽

Therapeutic Efficacy ◽

Composite Structures ◽

Gelation Time ◽

Polymeric Materials ◽

Gellan Gum ◽

Traditional Use

Rheumatoid arthritis is a rheumatic disease for which a healing treatment does not presently exist. Silk fibroin has been extensively studied for use in drug delivery systems due to its uniqueness, versatility and strong clinical track record in medicine. However, in general, natural polymeric materials are not mechanically stable enough, and have high rates of biodegradation. Thus, synthetic materials such as gellan gum can be used to produce composite structures with biological signals to promote tissue-specific interactions while providing the desired mechanical properties. In this work, we aimed to produce hydrogels of tyramine-modified gellan gum with silk fibroin (Ty–GG/SF) via horseradish peroxidase (HRP), with encapsulated betamethasone, to improve the biocompatibility and mechanical properties, and further increase therapeutic efficacy to treat rheumatoid arthritis (RA). The Ty–GG/SF hydrogels presented a β-sheet secondary structure, with gelation time around 2–5 min, good resistance to enzymatic degradation, a suitable injectability profile, viscoelastic capacity with a significant solid component and a betamethasone-controlled release profile over time. In vitro studies showed that Ty–GG/SF hydrogels did not produce a deleterious effect on cellular metabolic activity, morphology or proliferation. Furthermore, Ty–GG/SF hydrogels with encapsulated betamethasone revealed greater therapeutic efficacy than the drug applied alone. Therefore, this strategy can provide an improvement in therapeutic efficacy when compared to the traditional use of drugs for the treatment of rheumatoid arthritis.

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Polypyrrole/PU hybrid hydrogels: electrically conductive and fast self-healing for the potential application in body-monitor sensor

New Journal of Chemistry ◽

10.1039/d1nj00616a ◽

2021 ◽

Author(s):

Zhanyu Jia ◽

Guangyao Li ◽

Juan Wang ◽

shouhua Su ◽

Jie Wen ◽

...

Keyword(s):

Mechanical Properties ◽

Electrical Conductivity ◽

Potential Application ◽

Self Healing ◽

Electrically Conductive ◽

Sensor Application ◽

Hybrid Hydrogels ◽

Health Monitor

Conductivity, self-healing and moderate mechanical properties are necessary for multifunctional hydrogels which have great potential in health-monitor sensor application. However, the combination of electrical conductivity, self-healing and good mechanical properties...

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Self-healing, Highly Elastic and Amphiphilic Silicone-based Polyurethane for Antifouling Coatings

Journal of Materials Chemistry B ◽

10.1039/d0tb02465a ◽

2021 ◽

Author(s):

Xiaobin Lin ◽

Qingyi Xie ◽

Chunfeng Ma ◽

Guangzhao Zhang

Keyword(s):

Mechanical Properties ◽

Silicone Elastomer ◽

Self Healing ◽

Fouling Resistance ◽

The Poor ◽

Antifouling Coatings ◽

Fouling Release

Silicone elastomer coatings have attracted increasing attention owing to its eco-friendly nature, excellent fouling release ability and drag-reducing property. However, the poor mechanical properties and lack of fouling resistance limits...

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The preparation of hydrogels with highly efficient self-healing and excellent mechanical properties

Journal of Molecular Liquids ◽

10.1016/j.molliq.2021.115581 ◽

2021 ◽

Vol 329 ◽

pp. 115581

Author(s):

Chaoxian Chen ◽

Zhongcun Li ◽

Siwen Chen ◽

Lingzhi Kong ◽

Zhihao Guo ◽

...

Keyword(s):

Mechanical Properties ◽

Self Healing ◽

Highly Efficient

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Mechanical and Morphological Properties of Bio-Phenolic/Epoxy Polymer Blends

Molecules ◽

10.3390/molecules26040773 ◽

2021 ◽

Vol 26 (4) ◽

pp. 773

Author(s):

Ahmad Safwan Ismail ◽

Mohammad Jawaid ◽

Norul Hisham Hamid ◽

Ridwan Yahaya ◽

Azman Hassan

Keyword(s):

Mechanical Properties ◽

Phase Separation ◽

Polymer Blends ◽

Epoxy Polymer ◽

Flexural Modulus ◽

Polymeric Materials ◽

Morphological Properties ◽

Comparison Results ◽

Unique Material ◽

Different Types

Polymer blends is a well-established and suitable method to produced new polymeric materials as compared to synthesis of a new polymer. The combination of two different types of polymers will produce a new and unique material, which has the attribute of both polymers. The aim of this work is to analyze mechanical and morphological properties of bio-phenolic/epoxy polymer blends to find the best formulation for future study. Bio-phenolic/epoxy polymer blends were fabricated using the hand lay-up method at different loading of bio-phenolic (5 wt%, 10 wt%, 15 wt%, 20 wt%, and 25 wt%) in the epoxy matrix whereas neat bio-phenolic and epoxy samples were also fabricated for comparison. Results indicated that mechanical properties were improved for bio-phenolic/epoxy polymer blends compared to neat epoxy and phenolic. In addition, there is no sign of phase separation in polymer blends. The highest tensile, flexural, and impact strength was shown by P-20(biophenolic-20 wt% and Epoxy-80 wt%) whereas P-25 (biophenolic-25 wt% and Epoxy-75 wt%) has the highest tensile and flexural modulus. Based on the finding, it is concluded that P-20 shows better overall mechanical properties among the polymer blends. Based on this finding, the bio-phenolic/epoxy blend with 20 wt% will be used for further study on flax-reinforced bio-phenolic/epoxy polymer blends.

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