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Aiming at fabricating high damping rubber composites, the acrylic rubber ACM was incorporated with sliding graft copolymer (SGC) materials. SGC is a novel supramolecular material with sliding crosslink junctions, and it acts as a high damping phase in ACM/SGC composites. Fourier transform infrared spectroscopy reveals the presence of two types of h...
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... rubber (ACM, AR-801, TOPHE Industry Co., Ltd., Japan), used as a matrix in this study, was obtained through the polymerization of ethyl acrylate and composed of active chlorine as cure site groups. Its chemical structure and vulcanization mechanism are illustrated in Fig. 3. A sliding gra copolymer (SGC) with a molecular weight of 6 00 000 (Tianjin Weirui Supramolecular Materials Technology Co., Ltd., China) was also utilized. The received SGC material contains crosslink agent (HMDI). Other compounding ingredients (Sinopharm Chemical Reagent Co., Ltd., China) were used without further purication. ...
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... Beyond 40% strain, when the filler network is disrupted, the tan δ value rises sharply. The tan δ value of MPET 3/NR exceeds that of PET 3/NR, indicating greater energy dissipation during the destruction of the packing network under high strain conditions [32][33][34]. ...
The excellent bonding performance between polyester fibers and rubber is key to the high elasticity and fatigue resistance of rubber composite materials. Here, the modified polyester staple fiber (MPET) was obtained by microwave irradiation and surface modification with γ-aminopropyltriethoxysilane (KH550). The results revealed that KH550 reacted with the carboxyl groups on the surface of PET and thus adhered to the fiber surface, which was beneficial in improving compatibility with rubber. When reinforcing natural rubber (NR), MPET combined with the NR molecular chain flexibility due to the rigidity of its own main chain structure. This synergy resulted in the formation of inter-chain entanglements, contributing to a reduction in internal energy dissipation and heat generation within the composite. As the MPET dosage is augmented, the maximum torque of the NR compound during the mixing process exhibits an upward trend. In parallel, the cured NR rubber experiences a gradual reduction in both tensile strength and elongation at break, accompanied by a progressive increase in hardness. Furthermore, a notable elevation in tear strength is observed. This observed trajectory accentuates the intricate interplay between the dosage of MPET and the mechanical attributes of the NR rubber composite. The results of Rubber Processing Analyzer (RPA), Dynamic Mechanical Analysis (DMA) and Scanning Electron Microscope (SEM) indicate that the interfacial bonding between MPET and NR shows promising prospects as rigid short fibers for reinforcing non-polar rubber.
... Energy is dissipated through motion within the material, and the external energy is converted into heat energy called damping performance. 36 The unique viscoelasticity of polymers makes them popular as vibration damping materials in many fields, especially in earthquake protection. 37−40 Therefore, PLA-based TPUs show an excellent damping performance at room temperature, and the methyl pendant on the molecular chain can effectively enhance the damping performance while its mechanical properties are wellmaintained. ...
Petroleum-based polymer materials heavily rely on nonrenewable petrochemical resources, and damping materials are an important category of them. As far as green chemistry, recycling, and damping materials are concerned, there is an urgent need for renewable and recyclable biobased materials with high damping performance. Thus, this study designs and synthesizes a series of polylactic acid-based thermoplastic polyurethanes (PLA-based TPUs) composed of modified polylactic acid polyols, 4,4′-diphenylmethane diisocyanate, and 1,4-butanediol. PLA-based TPUs, as prepared, display excellent mechanical properties, damping performance, and biocompatibility. Otherwise, they can be used for three-dimensional printing (3D printing). Under multiple recycling, the overall performance of PLA-based TPUs is still maintained well. Overall, PLA-based TPUs, as designed in this article, show a potential application in damping materials under room temperature and personalized shoes via 3D printing and could realize resource recycling and material reuse.
... Generally, there are three modification strategies to improve the damping of materials. Firstly, based on the large mechanical loss around the glass transition temperature (Tg), the damping could been enhanced by blending with low-or high-Tg components [5,6], copolymerization with different constituents [7,8], and formation the interpenetrating polymer network (IPN) [9,10]. However, significant changes of tanδ and modulus during the transition from glassy to rubbery state are inevitable. ...
The incorporation of additive into rubber matrix is a promising approach toward desirable damping materials. However, the design and selection of additives remain a challenge. Herein, tetraphenylphenyl-modified damping additives were synthesized by Diels-Alder chemistry. The effects of additives on the mechanical and morphological properties of phenyl silicone rubber were investigated experimentally and computationally. Experimental results showed that the addition of additives substantially improved the damping while preserving excellent mechanical properties. The composite with 15 phr tetraphenylphenyl-modified dimethylpolysiloxane (TPP-VMPS-3) exhibited a broad plateau of loss factor (tanδ >0.25) from −50 to 30 °C, effectively expanding the damping temperature range. When the composite incorporated 15 phr tetraphenylphenyl-modified methylphenylpolysiloxane (TPP-VPMPS), the tanδ increased from 0.09 to 0.21 at 150 °C, showing excellent high-temperature damping performance. Furthermore, molecular dynamics (MD) simulation provided mechanistic insights into the phase separation and relaxation behavior of composites by studying the compatibility, interaction mechanism, and diffusion characteristic. The results demonstrated that the enhanced intermolecular interactions and steric hindrance were the crucial reason for the improvement of damping. This work shed light on the relationship among composition, structure and property, which may provide a framework for preparing high-performance silicone composites via the synergistic experimental and computational method.
Matrices are essentially binders for the reinforcements of composite material. Appropriate selection of fine chemicals is vital for the creation of desired matrices for generating composite materials. In fact, matrix is a subclass of a composite material. Matrices are generally of four kinds such as (i) polymer (hard as well as flexible), (ii) metal, (iii) ceramic, and (iv) cement. Each type of these subclasses of the matrix is discussed with a brief of their pros and cons. Polymer matrices are generally organic based whereas metal or ceramic matrices are inorganic in nature. Hard plastic matrix as well as flexible rubbery matrix are also discussed in the light of their applications. Carbon as matrix material for hi-tech C/C (carbon/carbon) composite materials is also stated. Cement is a special kind of inorganic matrix material because of its very special solidification mechanism during the formation of concrete composite; and it carries bulk values in the engineering area. For higher temperatures, carbon, ceramic or metal matrix materials are useful. Ceramics possess various conductivities, but they have poor tensile strength despite their ability to afford high-temperature products. Generally lightweight metals such as titanium, aluminum, magnesium, and intermetallics such as Ni-aluminide and Ti-aluminide are used; and the operating temperature can be extended to 2000 °C. The advantages of metal matrices are higher strength and ductility than those of polymers. Carbon matrix based carbon/carbon (C/C) composites can be used even at the temperature of ~3000 °C, but are preferred only in critical engineering areas of applications. Different types of matrix material may also prove to be efficacious constituent item for innovative design of integrated structure in the ever challenging area of Blast and penetration resistant materials (BPRM).
High‐performance damping materials are significant toward reducing vibration and maintaining stability for industrial applications. Herein, a yolk–shell piezoelectric damping mechanism is reported, which can enhance mechanical energy dissipation and improve damping capability. With the addition of yolk–shell particles and carbon nanotube (CNT) conductive network, damping properties of various resin matrices are enhanced with the energy dissipation path of mechanical to electrical to heat energy. Particularly, the peak loss factor of epoxy composites reaches 1.91 and tan δ area increases by 25.72% at 20 °C. The results prove the general applicability of yolk–shell piezoelectric damping mechanism. Besides, the novel damping materials also exhibit excellent flexibility, stretchability, and resilience, offering a promising application toward damping coating, indicating broad scope of application in transportation and sophisticated electronics, etc.
Eucommia ulmoides gum (EUG) was a biobased hard rubber with the prospected broad applications in rubber products, whereas possessed poor elasticity and weak damping functionality at room temperature. After modification of EUG by triazolinedione-based Alder-ene reaction, the modified EUG containing varied amount of polar and branched pendants could become a new type of soft rubber and functional material with excellent damping properties, and especially exhibited the unique damping plateau with a wide effective damping temperature range of 132 °C covering from −35 °C to 97 °C, large loss factor of 0.8, high damping coefficient of 0.53, and more hysteresis loss of 0.35. Therefore, this sustainable elastomeric material with adjustable damping performance would absorb more vibrational mechanical energy in a wide temperature range, and have broadened applications in energy-absorption devices and shock-absorbing materials.
In a system initiated by potassium persulfate, an ultra‐cold‐resistant reactive chlorinated resin rubber was synthesized by emulsion polymerization. In this emulsion polymerization, ethyl acrylate and butyl acrylate were used as the main components of the rubber monomer. 2‐Methoxyethyl acrylate was used as a cold‐resistant monomer, and vinyl chloroacetate was used as a vulcanized monomer. Fourier transform infrared spectroscopy, thermogravimetry–gas chromatography–mass spectrometry, ¹H NMR, ¹³C NMR and other rubber detection standards were used to characterize the structure and properties of the synthetic acrylate rubber. Studies showed that acrylate rubber was synthesized by emulsion polymerization, and each monomer achieved random copolymerization with high conversion. The synthetic acrylate rubber has excellent low‐temperature resistance (the brittleness temperature is −36.5 °C). In addition, the rubber has excellent mechanical properties and a high vulcanization speed and is a fast‐vulcanizing acrylic rubber. © 2022 Society of Industrial Chemistry.
Vibration and noise are ubiquitous in social life, which severely damage machinery and adversely affect human health. Thus, the development of materials with high-damping performance is of great importance. Rubbers are typically used as damping materials because of their unique viscoelasticity. However, they do not satisfy the requirements of different applications with various working conditions. In this study, the advantages of the high loss factor of styrene butadiene rubber (SBR) are combined with the strong designability of polyurethane. Hydroxyl-terminated solution-polymerized styrene butadiene rubbers (HTSSBRs) with different structures are prepared using anionic polymerization. HTSSBRs are then used as the soft segment during the synthesis of temperature-tunable high-damping performance polyurethane (HTSSBR-polyurethane (PU)). The prepared HTSSBR-PUs with different structures exhibit excellent loss performance, a maximum loss factor (tan δmax) of above 1.60, and an effective damping performance over a wide temperature range compared to traditional SBR and polyurethane. Therefore, this work offers an effective method for the design of damping materials with adjustable properties.
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Ring-sliding behavior in polyrotaxanes imbues gels, elastomers, and glasses with remarkable stress-dissipation and actuation properties. Since these properties can be modulated and tuned by structural parameters, many efforts have been devoted to developing synthetic protocols that define the structures and properties of slide-ring materials. We introduce post-synthetic modifications of slide-ring gels derived from unmodified α-cyclodextrin and poly(ethylene glycol) polyrotaxanes that enable (i) actuation and control of the thermo-responsive lower critical solution temperature (LCST) behavior of ring-modified slide-ring hydrogels, and (ii) chemically bonding separate gels into hybrid or shape-reconfigured macro-structures with a slide-ring adhesive solution. The mechanical properties of the post-modified gels have been characterized by shear rheology and uniaxial tensile tests, while the corresponding xerogels were characterized by wide-angle X-ray scattering. These demonstrations show that post-synthetic modification offers a practical solution for re-configuring the properties and shapes of slide-ring gels.
