Abstract
Though hindered phenol/polymer-based hybrid damping materials, with an excellent loss factor, attract more and more attention, the significantly decreased mechanical property and the narrow damping temperature range limit the application of such promising materials. To solve the problems, a polyurethane (hindered phenol)/polyvinyl acetate multilayer system with varied layer numbers was prepared in this study. The multilayer microstructures were first verified through the scanning electron microscopy. A subsequent molecular dynamics simulation revealed the promoted diffusion of polyurethane (hindered phenol) and polyvinyl acetate layers, the compact chain packing of the polyurethane (hindered phenol) layer, the extended chain packing of the polyvinyl acetate layer, the intermolecular hydrogen bonds among the three components and the enhanced interface interactions between the two layers in a quantitative manner. Further the mechanical and dynamic mechanical analysis detected the successful preparation of the multilayer hybrids with simultaneously improved mechanical and damping properties. Then, by a combination of molecular dynamics simulation and experiment, the relationship between the structure evolution and the properties of the multilayer hybrids was established, which was expected to have some guiding significance for industrial production.
Highlights
Since it was proposed in 1920 [1], hydrogen bonds (HBs) have attracted enormous attention for nearly a century [2,3,4,5]
The proposed structure of thermoplastic polyurethane (TPU), polyvinyl acetate (PVAc) and AO-70 were generated by using the rotational isomeric state model of Flory, initial structures were ordinal energy minimized through the steepest descent, conjugate gradient and newton method to a convergence level of 1 × 10−5 kcal/mol/A with maximum iterations of 4 million, and the structures were dynamic equilibrated in a constant NVT (Constant number, Constant volume, constant temperature) condition at 25 ◦ C for 5 nanosecond with a time step of 1 femtosecond to avoid excessive overlaps between chains (Figure 2a–c)
The amorphous cells and confined layers were ordinal energy minimized through the steepest descent, conjugate gradient and newton method to a convergence level of 1 × 10−5 kcal/mol/A with maximum iterations of 4 million, and the amorphous cells and confined layers were dynamic equilibrated in a constant NVT condition at 25 ◦ C for 4 ns with a time step of 1 fs (Figure 2d,e and Figure S2 taking a TA-32 layer and PVAc-32 layer for example, from the Supplementary Materials)
Summary
Since it was proposed in 1920 [1], hydrogen bonds (HBs) have attracted enormous attention for nearly a century [2,3,4,5]. To explore the damping mechanism of the nitrile rubber/HP hybrids in a quantitative manner, molecular dynamics (MD) simulation was adopted [19]. The mechanical property of the shell-like structure may be controllable regulated [34], the key lies in the strength of the interface interactions, which may be regulated by HBs. to prepare a useful polymer-based hybrid with excellent comprehensive performance, a multilayer system with thermoplastic polyurethane (TPU) and polyvinyl acetate (PVAc) as a matrix was prepared in this study by combining our previous works [35,36]. (1) prepare a hybrid with excellent properties by combining the advantages of polymer/HP system and multilayered co-extrusion system and (2) reveal the damping mechanism of the multilayered structure at the molecular level and in a quantitative manner
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
