Substrate elastomeric

As previously discussed, the JKR theory predicts that the detachment force is independent of the Young s modulus. Yet despite that, when Gady et al. [117] measured the detachment force of polystyrene particles from two elastomeric substrates having Young s moduli of 3.8 and 320 MPa, respectively, they found that the detachment force from only the more compliant substrate agreed with the predicted value. The force needed to separate the particle from the more rigid substrate was about a factor of 20 lower. Estimates of the penetration depth revealed that the particles would penetrate into the more compliant substrate more deeply than the heights of the asperities. Thus, in that case, the spherical particle approximation would be reasonable. On the other hand, the penetration depth... 

In this chapter, we will review the consequences of solid deformation in the kinetics of the spreading of a liquid on a soft material, in both wetting and dewetting modes. The influence of solid deformation induced by the liquid surface tension will be shown in the case of a liquid drop placed on a soft elastomeric substrate and in the case of an unstable liquid layer dewetting on a soft rubber. The impact of solid deformation on the kinetics of the wetting or dewetting of a liquid will be analyzed theoretically and illustrated by a few concrete examples. The consequences of solid deformation in capillary flow will be also analyzed. 

The values of Go and y are known and for the elastomer of Young s modulus of 2.1 MPa, [/o = 8 X 10 mm-s [12]. We can then evaluate 8 at ca. 20 mn. This value is perhaps a little high but of the same order of magnitude as earlier estimated [6]. Thus, despite some necessary approximations and simplifying hypotheses, we arrive at a semiquantitative explanation of the relationship between dewetting and therefore, presumably, wetting speed and the molecular structure of the elastomeric substrate. 

The purpose of this paper is to briefly review recent research into the effectiveness and mode of action of tin compounds as fire retardants in a number of halogenated and halogen-free, plastic and elastomeric substrates. 

Tne effectiveness of inorganic tin compounds as flame and smoke retardants, both alone and in combination with inorganic fillers, in several halogen-free thermoplastic, thermosetting and elastomeric substrates, is currently under investigation at the ITRI. 

Sun, Y. Kumar, V. Adesida, I. Rogers, J. A. 2006. Buckled and wavy ribbons of GaAs for high-performance electronics on elastomeric substrates. Adv. Mater. 18 2857-2862. 

In the situation depicted in Fig. 2, the film on the elastomeric substrate undergoes a buckling transition in order to relieve stress upon compression. In contrast... 

Fig. 2 Schematic depiction of wrinkle formation of a hard film in adhesive contact with a softer elastomeric substrate. The wavelength X is mainly determined by film thickness h and elastic properties of film and substrate. The amplitude A can be controlled by the strain...

The theoretical concept explained above is rather universal. It has few restrictions in terms of materials used for wrinkle formation. The main requirement is that the Young s modulus of the film is large as compared to the substrate elastomer. In addition, if micron- and sub-micron wavelengths are desired, the film thickness should be controllable on the nanoscale. In most of the work, polydimethylsiloxane (PDMS) was used as elastomeric substrate. Experimentally, both transient wrinkles, which only exist when macroscopic strains are applied, and permanent wrinkles, which remain in the absence of macroscopic strains, can be produced. Both cases are illustrated in Figs. 3 and 4 for the simplest situation of a uniaxial deformation. 

A case in point is an elastomeric substrate, such as compounded nitrile rubber. Generally, the user will specify the rubber part by compressive strength, extension, hardness, or other... 

TABLE F3 Surface Preparation Methods for Elastomeric Substrates... 

Y. Xia, E. Kim, X.-M. Zhao, J.A. Rogers, M. Prentiss and G.M. Whitesides, Complex optical surfaces formed by replica molding against elastomeric substrates. Science, 273 (1996) 347-349. 

In this paper, we approach this problem by utilizing an axisymmetric adhesion test involving the contact of a rigid glass hemispherical indenter with an elastomeric substrate. Application of these types of tests has been reviewed recently... 

In these tests, we assume that the contact stiffness of the elastomeric substrate is not substantially affected by the addition of the thin glassy or semicrystalline polymer layers. These layers deform by bending, and the load needed to bend the layers into conformity with the elastomer surface can be estimated from a simple plate deformation calculation. The deflection of the film can be modeled by the central loading of a disk [16], and comparing the stiffness of the disk to the contact stiffness of the elastomer substrate. For a circular plate that is loaded at the center and supported (but not clamped) at a radius of the stiffness is dependent on the modulus of the film, f, the thickness of the film, h, and its Poisson ratio v [Eq. (4)]. 

Lacour SP, Wagner S, Huang Z, Suo Z (2003) Stretchable gold conductors on elastomeric substrates. Appl Phys Lett 82 2404... 

Fu J, Wang YK, Yang MT, Desai RA, Yu X, Liu Z, Chen CS (2010) Mechanical regulation of cell function with geometrically modulated elastomeric substrates. Nat Methods 7(9) 733-736... 

Alexander, K. D. Skinner, K. Zhang, S. Wei, H. Lopez, R., Tunable SERS in Gold Nanorod Dimers Through Strain Control on an Elastomeric Substrate. Nano Lett. 2010,10, 4488-4493. 

Crapo PM, Wang Y. Physiologic comphance in engineered small-diameter arterial constructs based on an elastomeric substrate. Biomaterials 2010 31 1626-35. 

Gurlo and Clarke (2011) believe that an approach based on the nse of reversible swelling of multiple cracked palladium films in which the cracks act as nanogaps (Lee et al. 2010b) and elastomeric substrates as a compliant support for palladium films to accommodate the swelling can also lead to improvement of gas-sensing parameters of palladinm-based sensors. 

Alexander KD, Skinner K, Zhang S, Wei H, Lopez R (2010) Tunable SERS in gold nanorod dimers through strain control on an elastomeric substrate. Nano Lett 10 4488-4493... 

Plastic and elastomeric joints. The design of joints for plastic and elastomeric substrates follows the same practice as for metal. However, certain characteristics of these materials require special consideration. 

Strength and Versatility, High strength bonds are achieved to a wide variety of metallic, plastic, and elastomeric substrates. (See Table 5). 

Considerable effort has been made in the area of snail control in utilizing slow-release incorporated tri-n-butyl fluoride within elastomeric substrates.Using mostly rubber-type substrates, at least five different formulations are cited in controlling seven species of snails under a variety of conditions. Although all of these are physically entrapped, a variety of shapes and densities are now available to allow quite a range of use in the field. The citations in reference 26 showed complete control under a variety of conditions for periods up to 19 months long. 

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