Energy‐damping behaviors of poly(methyl acrylate‐co‐divinylbenzene) microspheres coated with a porous nickel–phosphorus layer

Abstract

Hybrid microspheres of poly(methyl acrylate-co-divinylbenzene) (PMADVB) with a thin and porous nickel-phosphorus (Ni-P) alloy layer were prepared via suspension polymerization and electroless nickel plating. The characterization of pristine and nickel-coated microspheres was carried out with a differential scanning calorimeter and a scanning electron spectroscope equipped with an energy-dispersive system. The glass-transition range of Ni-P-coated PMADVB was broadened and extended in the higher temperature direction. This effect allowed the PMADVB network to embrace more diversified energy states of the segment motion, this being a desired feature for damping sound waves. The low-frequency (100 -1000-Hz) sound absorption behavior of the microspheres was tested with a sound attenuation kit. Besides the testing of their low-frequency damping performance, an investigation into the ultrasonic-wave (ϳ35 kHz) absorption feature of the microspheres was conducted through chemical means; that is, the attenuation to the ultrasonic wave with respect to the unprotective situation was assessed through the chemisorption extent of copper ions on a biomass adsorbent. The Ni-P deposition layer was found to augment the damping capacity of the polymer network. The alloy layer was determined to cause an expansion of the glass-transition range of PMADVB and its wave-scattering capability because this layer was made up of submicrometer metallic grains. In this work, the particulars of the metal-polymer interactions were associated with a core-shell structure. The metal outer layer was thought to create a spherical temperature field inside the PMADVB network, and concerted motions of the polymer segments resulted.

Mechanical behaviors and molecular deformation mechanisms of polymers under high speed shock compression: A molecular dynamics simulation study

“…Polymeric materials have a wide range of engineering applications [1,2], which stimulate huge interests in academics due to their fantastic mechanical, thermal and electrical properties [3e6]. The material properties of polymers are determined not only by their chemical composition but also by the mutual arrangement of their macromolecule [7,8].…”

Acoustic attenuation characteristics of surface‐modified polymeric porous microspheres

“…Nevertheless, it may note that too thick a Ni layer produces a converse effect according to our previous study. 11 The pink and white noise test also revealed that incorporating PEA into SD matrix resulted in lifting TL level. On the basis of the changes in SD morphology (Fig.…”

“…To overcome this limitation, the electroless nickel (EN) plating system shows the advantage only if the plating conditions are deliberately lessened to avoid generation of heavy plating. Following our previous work, 11 we continued with using the MD resin, which contains both rigid and soft blocks linked by chemical bonding, as substrate of EN. The plating gave rise to metallic Ni grains (<50 nm) on MD beads, and smaller Ni particles were found on MD12 than on MD11 and MD21 (Fig.…”

Porous Polymers by Controlling Phase Separation during Vapor Deposition Polymerization

“…The pore-size and morphology can be adjusted during fi lm growth to create customizable, graded structures, or skin layers. Conformal and porous fi lms grown from such a technique could be relevant to membranes for separations, [ 3,13,14 ] cellular scaffolding of tissues or implants, [ 15,16 ] fabrication of cushions or coatings for micro-electromechanical systems, [ 17 ] superhydrophobic coatings, [ 18 ] membrane oxygenators, [ 19 ] acoustic dampers, [ 20,21 ] and fabrication of foam layers for laser fusion targets. [ 22 ] Initiated chemical vapor deposition (iCVD) is a solventless free radical polymerization technique to grow polymer fi lms directly from the gas phase on various A template-free method is described to fabricate continuous-phase, porous polymer fi lms by simultaneous phase separation during vapor deposition polymerization.…”