Systematic evaluations of the properties of prosthetic facial materials began to appear in 1969 with a report by Cantor et a/. ’ They reported that plasticized poly(methyl methacrylate) was the best material with respect to resistance to tearing and degree of elongation. A year later, Walter2 reported the specific gravity, water sorption, thermal conductivity, strain in compression, and permane...

Abstract Bulk copolymerization of alkyl acrylates and cyclodextrin (CD) host monomers produced a single movable cross-network (SC). The CD units acted as crosslinking points in the obtained SC elastomer. Introducing crosslinks into poly(ethyl acrylate/butyl acrylate) copolymer resulted good toughness ( G f ) stress dispersion. Here, to improve Young’s modulus E elastomers, bulk liquid acrylate ...

We consider theoretically the properties of piezoelectricity in cholesteric elastomers. We deduce using symmetry considerations the piezoelectric contributions to the free energy in the context of a coarse-grained description of the material. In contrast to previous work we find that compressions or elongations of the material along the pitch axis do not produce a piezoelectric response, in agr...

This study presents a flexible magnetically-actuated micro fluid transport system utilizing an isotropic magnetorheological elastomer (MRE). Theoretical modeling and analysis of this system is presented for a two-dimensional model. This fluid transport system can propel the fluid by applying a fluctuating magnetic field on the MRE. The magneto-fluid-structure interaction analysis is employed to...

Elastomeric protein-based biomaterials, produced from elastin derivatives, are widely investigated as promising tissue engineering scaffolds due to their remarkable properties including substantial extensibility, long-term stability, self-assembly, high resilience upon stretching, low energy loss, and excellent biological activity. These elastomers are processed from different sources of solubl...

In a nematic elastomer the deformation of the polymer network chains is coupled to the orientational order of the mesogenic groups. Statistical arguments have derived the so-called neoclassical free energy that models this coupling. Here we show that the neoclassical model supplemented by the usual Frank energy predicts incompatible network strains associated with the formation of standard nema...

Constitutive equations are derived for the time-dependent behavior of particlereinforced elastomers at isothermal loading with finite strains. A rubbery polymer is modelled as a network of macromolecules bridged by junctions which can slip with respect to the bulk material under straining. A filled elastomer is thought of as an ensemble of meso-regions where sliding occurs with different rates....

OBJECTIVE This paper focused on optimal stress distribution in the mandibular bone surrounding a dental implant and is devoted to the development of a modified Osteoplant® implant type in order to minimize stress concentration in the bone-implant interface. MATERIAL AND METHODS This study investigated 0.4 mm thick layers of two elastomeric stress barriers incorporated into the dental implant ...

Cholesteric elastomers possess a macroscopic "phase chirality" as the director n rotates in a helical fashion along an optical axis z and can be described by a chiral order parameter alpha. This parameter can be tuned by changing the helix pitch p and the elastic properties of the network at formation. The cholesterics also possess a local nematic order, changing with temperature or during solv...

Elastomers and gels can often deformmultiple times their original length. The stretchability is insensitive to small cuts in the samples, but reduces markedly when the cuts are large. We show that this transition occurs when the depth of cut exceeds a material-specific length, defined by the ratio of the fracture energy measured in the large-cut limit and the work to rupture measured in the sma...