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Abstract Ceramic/polymer composites can be chemically stable, mechanically strong, and flexible, which make them candidates for electric devices, such as pressure or temperature sensors, energy storage or harvesting devices, actuators, and so forth. Depending on the application, various electrical properties are of importance. Polymers usually have low dielectric permittivity, but increased dielectric permittivity can be achieved by the addition of the ceramic fillers with high dielectric constant. With the aim to enhance dielectric properties of the composite without loss of flexibility, 5 wt% of BaTiO3‐Fe2O3powder was added into a polyvinylidene fluoride matrix. The powder was prepared by different synthesis conditions to produce core/shell structures. The effect of the phase composition and morphology of the BaTiO3‐Fe2O3core/shell filler on the structure and lattice dynamics of the polymer composites was investigated. Based on the results of the thermal analysis, various parameters of ceramic/polymer composites were determined. Differences in the phase composition and morphology of the filler have an influence on the formation of various polyvinylidene fluoride allomorphs and the degree of crystallinity. Furthermore, the dielectric performances of pure polyvinylidene fluoride and the polymer/ceramic composites were measured.
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Conformational Analysis of Oligomeric Models of Siloxane, Silazane and Siloxazane Ladder Polymers
Abstract Oligomeric models of linear ladder silanes, siloxanes and siloxazanes with seven repeat units consisting of four-, six-, or eight-membered rings were designed and their conformations in chloroform were explored. The Low Mode–Monte Carlo conformational method was used to explore oligomeric flexibility on the OPLS-2005/GBSA(CHCl3) potential energy surface to obtain a set of low energy structures for each oligomer. These structures were then optimized using B3LYP/6-31G*/SCRF-PBF(CHCl3) calculations. The results indicate complex conformational dynamics with mostly non-planar, curved structures. Electron delocalization from the lone pair of electrons on N or O into empty 3d orbitals on Si was not observed.
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- Award ID(s):
- 2320718
- PAR ID:
- 10634167
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Journal of Inorganic and Organometallic Polymers and Materials
- Volume:
- 34
- Issue:
- 7
- ISSN:
- 1574-1443
- Page Range / eLocation ID:
- 2893 to 2902
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/s10904-024-03181-6
