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Adhesion Between Components of Elastomeric Composite Materials
Published in Nicholas P. Cheremisinoff, Elastomer Technology Handbook, 2020
Nitrile rubber (NBR), acrylic rubber (ACM), and epichlorohydrine rubber (ECO) are used in rubber parts that are in contact with oils, fuels, and solvents. Applications for these, such as hoses, gaskets, diaphragms, and seals, are used because of their good oil, fuel, and solvent resistance.
Pressure-Sensitive Raw Materials
Published in István Benedek, Mikhail M. Feldstein, Technology of Pressure-Sensitive Adhesives and Products, 2008
Acrylics were developed as a raw material for PSA in the form of elastomers (rubbers) and viscoelastomers. Acrylic copolymers were the first class of viscoelastomers used for PSAs. Random and block copolymers have been synthesized as acrylic rubber. Both can be applied for solvent-based or HM adhesives. A wide range of acrylics is supplied as water-based dispersion. Recently, ready-to (in-line)-use acrylic oligomers were developed (see also Section 1.1.2). Advances in polymer chemistry and technology supplied a large range of viscoelastomers that are usable as pressure-sensitive raw materials, threatening the leading position of acrylics in this domain. Acrylics are available as solvent-based, water-based, and 100% solids. They are supplied as common acrylic rubbers and thermoplastic elastomers as well. Owing to their very large monomer basis, their copolymerizability by various procedures (including in-line technology-required radiation-induced polymerization), their built-in pressure sensitivity (which can be, if necessary, easily regulated by tackification, cross-linking, etc.), and their excellent aging and physiological properties, acrylics remain the main class of pressure-sensitive raw materials. Functionalized acrylics can be used for special products. For instance, side-chain fluoroacrylate monomers such as 1H,1H-pentadecafluoro-octyl acrylate and 1H,1H-heptafluorobutyl acrylate were used together with a nonfluorinated comonomer (acrylic acid) to obtain low-refractive-index polymers (see Applications of Pressure-Sensitive Products, Chapter 3). UV curing of urethane diacrylate was combined with thermal curing to obtain a structural adhesive used in electronics by Chang and Holguin (see Applications of Pressure-Sensitive Products, Chapter 3). Advances in macromolecular synthesis led to acrylic hydrogels (based mostly on hydroxyethyl acrylate) that are curable chemically or by radiation. Their use in electronics is discussed in Applications of Pressure-Sensitive Products, Chapter 3, by Chan and Holguin. Acrylic hydrogels are examined in comparison with other products in Chapter 7 by Feldstein et al. In Chapter 5, Foreman describes acrylic adhesives.
On high stiffness of soft robots for compatibility of deformation and function
Published in Advanced Robotics, 2022
Keisuke Hagiwara, Ko Yamamoto, Yoshihisa Shibata, Mitsuo Komagata, Yoshihiko Nakamura
From the results of the previous subsection, we select the combination of high pressure, oil and fiber-constraint type for our soft robot. However, there are multiple candidates for materials and fabrication methods. Figure 5 summarizes possible candidates of each factor and their combinations. The candidates of the oil-resistant material are as follows: Fluoro-rubber (FKM) is the most oil-resistant material: however, it is known that the cost is expensive.Acrylic rubber (ACM) is also oil-resistant material: however, the disadvantage is that ACM is not resistant for water and some of ester base synthetic oil.NBR is a standard material commonly used in an oil-hydraulic machine, as an oil seal for example.Rubber-like resins used in 3D printer is also a candidate of material because some of them are oil-resistant, such as TangoGray (FLX950). 1 Although 3D printer allows us to fabricate a complicated 3D shape, the anisotropy by the printing direction and weak tensile strength 2 are not suitable for the high-pressure actuation: a rubber-like resin often tear, and oil leaks out during deformation.