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1. POSS-ProDOT crosslinking of PEDOT

   https://doi.org/10.1039/c7tb00598a  

   Wei, Bin; Liu, Jinglin; Ouyang, Liangqi; Martin, David C. (January 2017, Journal of Materials Chemistry B)

   Alkoxy-functionalized polythiophenes such as poly(3,4-ethylenedioxythiophene) (PEDOT) and poly(3,4-propylenedioxythiophene) (PProDOT) have become promising materials for a variety of applications including bioelectronic devices due to their high conductivity, relatively soft mechanical response, good chemical stability and excellent biocompatibility. However the long-term applications of PEDOT and PProDOT coatings are still limited by their relatively poor electrochemical stability on various inorganic substrates. Here, we report the synthesis of an octa-ProDOT-functionalized polyhedral oligomeric silsesquioxane (POSS) derivative (POSS-ProDOT) and its copolymerization with EDOT to improve the stability of PEDOT coatings. The POSS-ProDOT crosslinker was synthesized via thiol–ene “click” chemistry, and its structure was confirmed by both Nuclear Magnetic Resonance and Fourier Transform Infrared spectroscopies. PEDOT copolymer films were then electrochemically deposited with various concentrations of the crosslinker. The resulting PEDOT- co -POSS-ProDOT copolymer films were characterized by cyclic voltammetry, Electrochemical Impedance Spectroscopy, Ultraviolet-Visible spectroscopy and Scanning Electron Microscopy. The optical, morphological and electrochemical properties of the copolymer films could be systematically tuned with the incorporation of POSS-ProDOT. Significantly enhanced electrochemical stability of the copolymers was observed at intermediate levels of POSS-ProDOT content (3.1 wt%). It is expected that these highly stable PEDOT- co -POSS-ProDOT materials will be excellent candidates for use in bioelectronics devices such as neural electrodes. 

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2. Fabrication and Mechanical Properties of POSS Coated CNTs Reinforced Expancel foam core Sandwich Structures

   https://doi.org/10.2174/2452271604999201123193149  

   Jones, Wanda; Sapkota, Bedanga; Simpson, Brian; Hassan, Tarig A.; Jeelani, Shaik; Rangari, Vijaya (November 2020, Current Applied Polymer Science)

   null (Ed.)

   Background:: Sandwich structures are progressively being used in various engineering applications due to the superior bending-stiffness-to-weight ratio of these structures. We adapted a novel technique to incorporate carbon nanotubes (CNTs) and polyhedral oligomeric silsesquioxanes (POSS) into a sandwich composite structure utilizing a sonochemical and high temperature vacuum assisted resin transfer molding technique. Objective:: The objective of this work was to create a sandwich composite structure comprised of a nanophased foam core and reinforced nanophased face sheets, and to examine the thermal and mechanical properties of the structure. To prepare sandwich structure, POSS nanoparticles were sonochemically attached to CNTs and dispersed in a high temperature resin system to make the face sheet materials and also coated on expandable thermoplastic microspheres for the fabrication of foam core materials. Method:: The nanophased foam core was fabricated with POSS infused thermoplastic microspheres (Expancel) using a Tetrahedron MTP-14 programmable compression molder. The reinforced nanophased face sheet were fabricated by infusing POSS coated CNT in epoxy resin and then curing into a compression stainless steel mold. Result:: Thermal analysis of POSS-infused thermoplastic microspheres foam (TMF) showed an increase in thermal stability in both nitrogen and oxygen atmospheres, 19% increase in thermal residue were observed for 4 wt% GI-POSS TMF compared to neat TMF. Quasi-static compression results indicated significant increases (73%) in compressive modulus, and an increase (5%) in compressive strength for the 1 wt% EC-POSS/CNTs resin system. The nanophased sandwich structure constructed from the above resin system and the foam core system displayed an increase (9%) in modulus over the neat sandwich structure. Conclusion:: The incorporation of POSS-nanofillier in the foam core and POSS-coated nanotubes in the face sheet significantly improved the thermal and mechanical properties of sandwich structure. Furthermore, the sandwich structure that was constructed from nanophased resin system showed an increase in modulus, with buckling in the foam core but no visible cracking. 

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3. Ion Pair Integrated Organic‐Inorganic Hybrid Electrolyte Network for Solid‐State Lithium Ion Batteries

   https://doi.org/10.1002/ente.201800431  

   Yang, Guang; Fan, Baoyan; Liu, Feihua; Yao, Fangzhou; Wang, Qing (November 2018, Energy Technology)

   Abstract A class of organic‐inorganic hybrid electrolyte with ion pair integrated network (X‐POSS‐IL‐LiTFSI) has been prepared by crosslinking of oligomeric octasilsesquioxanes grafted with imidazolium‐based ionic liquids for solid state lithium ion battery applications. X‐POSS‐IL‐LiTFSI is thermally stable and highly amorphous, and shows high ionic conductivities and excellent electrochemical stability. With further immobilization of a small fraction of ionic liquid, the ionic conductivity of X‐POSS‐IL‐LiTFSI has been significantly improved, e. g. 1.4×10⁻⁴ S/cm at ambinet temperature, to the level required by the practical battery applications, while maintaining the demensional integity. The coin cells of lithium batteries with the plasticized X‐POSS‐IL‐LiTFSI electrolytes exhibit high specific capacities at both ambient and elevated temperatures. 

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4. Instability of the Octahedral Symmetry in Si8O12H8 and Ge8O12H8: A Consequence of the Pseudo-Jahn–Teller Effect

   https://doi.org/10.1007/s10904-025-03970-7  

   Muya, Jules Tshishimbi; Ceulemans, Arnout; Parish, Carol (August 2025, Journal of Inorganic and Organometallic Polymers and Materials)

   Abstract The symmetry breaking in octahedral silsesquioxane and its germanium analogues (Si₈O₁₂H₈and Ge₈O₁₂H₈) has been investigated using the M06-2X/6-31++G(3df, 3pd) method and group theory. Both structures undergo$${O}_{h}\downarrow {T}_{h}$$symmetry breaking, characterized by pseudo-Jahn−Teller stabilization energies of 0.22 kcal/mol for Si-POSS and 9.82 kcal/mol for Ge-POSS. Under the influence of the pseudo-Jahn–Teller effect, the distortion vector involves the vibrational a_2gmode with imaginary frequency. The distortion forces in O_h-POSS are predominantly localized on the oxygen atoms and driven by the coupling between the lowest unoccupied molecular orbital (a_1g) and the highest occupied molecular orbital (a_2g). The symmetry breaking is attributed to a pseudo-Jahn–Teller mechanism of type (a_2gx a_1g) = a_2g. The symmetrical substitution of oxygen atoms by X (where X = C, N, P) results in viable T_h-Si₈X₁₂H₈and T_h-Ge₈X₁₂H₈structures. The observed pseudo-Jahn–Teller distortion and substitutional symmetry breaking caused by X indicates a consistent electronic relaxation mechanism, characterized by the formation of C=C, N=N and P=P bonds on the POSS cubic faces, which serves as hallmarks of stability. Additionally, we find that the volume of substituted T_h-symmetrical POSS is sufficiently large to accommodate small ions. 

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5. Improved Precipitation Typing Using POSS Spectral Modal Analysis

   https://doi.org/10.1175/JTECH-D-20-0075.1  

   Sheppard, Brian E.; Thurai, Merhala; Rodriguez, Peter; Kennedy, Patrick C.; Hudak, David R. (March 2021, Journal of Atmospheric and Oceanic Technology)

   null (Ed.)

   Abstract The Precipitation Occurrence Sensor System (POSS) is a small X-band Doppler radar that measures the Doppler velocity spectra from precipitation falling in a small volume near the sensor. The sensor records a 2D frequency of occurrence matrix of the velocity and power at the mode of each spectrum measured over 1 min. The centroid of the distribution of these modes, along with other spectral parameters, defines a data vector input to a multiple discriminant analysis (MDA) for classification of the precipitation type. This requires the a priori determination of a training set for different types, particle size distributions (PSDs), and wind speed conditions. A software model combines POSS system parameters, a particle scattering cross section, and terminal velocity models, to simulate the real-time Doppler signal measured by the system for different PSDs and wind speeds. This is processed in the same manner as the system hardware to produce bootstrap samples of the modal centroid distributions for the MDA training set. MDA results are compared to images from the Multi-Angle Snowflake Camera (MASC) at the MASCRAD site near Easton, Colorado, and to the CSU–CHILL X-band radar observations from Greeley, Colorado. In the four case studies presented, POSS successfully identified precipitation transitions through a range of types (rain, graupel, rimed dendrites, aggregates, unrimed dendrites). Also two separate events of hail were reported and confirmed by the images. 

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