The Recent Advances of Polymer-POSS Nanocomposites With Low Dielectric Constant

This study provides a comprehensive overview of the preparation methods for polyhedral oligomeric silsesquioxane (POSS) monomers and polymer/POSS nanocomposites. It focuses on the latest advancements in using POSS to design polymer nanocomposites with reduced dielectric constants. The study emphasizes exploring the potential of POSS, either alone or in combination with other materials, to decrease the dielectric constant and dielectric loss of various polymers, including polyimides, bismaleimide resins, poly(aryl ether)s, polybenzoxazines, benzocyclobutene resins, polyolefins, cyanate ester resins, and epoxy resins. In addition, the research investigates the impact of incorporating POSS on improving the thermal properties, mechanical properties, surface properties, and other aspects of these polymers. The entire study is divided into two parts, discussing systematically the role of POSS in reducing dielectric constants during the preparation of POSS composites using both physical blending and chemical synthesis methods. The goal of this research is to provide valuable strategies for designing a new generation of low dielectric constant materials suitable for large-scale integrated circuits in the semiconductor materials domain.

Preparation of Carbon nanotubes and Polyhedral oligomeric-Reinforced Molecularly Imprinted Polymer Composites for Drug Delivery of Gallic acid

In this paper, an enhanced imprinting effect of utilizing single wall carbon nanotubes (SWCNT) and polyhedral oligomeric silsesquioxanes (POSS) was suggested to improve drug delivery. The combination of 1-butyl-3-methylimidazoliumtetrafluoroborate ([BMIM]BF₄), tetrahydrofuran (THF) and choline chloride-ethylene glycol (ChCl / EG) were used as a ternary porogen to prepare molecularly imprinted polymer (MIPs) doped with SWCNT and POSS. In the presence of gallic acid (GAL), 4-vinylpyridine (4-VP) and ethylene glycol dimethacrylate (EDMA) was functional monomer and crosslinker, respectively. The structure and morphological parameters of the MIP composite, such as surface area and pore size distribution, were also measured. In the studies of in vitro releases, superior controlled release characteristics can be achieved due to the enhanced imprinting effect of the MIPs doped with POSS and SWCNT. In vivo release studies showed that the POSS-SWCNT MIP had the maximum plasma concentration after 4 hours. Compared with the control MIPs and NIP, the POSS-SWCNT MIP displayed a maximum AUC_0-9 of 544.73 (ng h mL^-1), while only 327.48, 212.91, 230.35 and 275.13 (ng h mL^-1) for the POSS MIP, SWCNT MIP, MIP and POSS-SWCNT NIP, respectively.

Unveiling the hybrid interface in polymer nanocomposites enclosing silsesquioxanes with tunable molecular structure: Spectroscopic, thermal and mechanical properties

Organic-inorganic nanobuilding blocks (NBBs) based on silsesquioxanes (SSQs) have potential applications as nanofillers, thermal stabilizers, and rheological modifiers, which can improve thermomechanical properties of polymer hosts. The possibility to tune both siloxane structure and pendant groups can promote compatibilization and peculiar interactions with a plethora of polymers. However, the control on SSQs molecular architecture and functionalities is usually delicate and requires careful synthetic details. Moreover, investigating the influence of NBBs loading and structure on the hybrid interface and, in turn, on the polymer chains mobility and mechanical properties, may be challenging, especially for low-loaded materials. Herein, we describe the preparation and characterization of polybutadiene (PB) nanocomposites using as innovative fillers thiol-functionalized SSQs nanobuilding blocks (SH-NBBs), with both tailorable functionality and structure. Swelling experiments and, more clearly, solid-state NMR, enlightened a remarkable effect of SH-NBBs on the molecular structure and mobility of the polymeric chains, envisaging the occurrence of chemical interactions at the hybrid interface. Finally, thermal and DMTA analyses revealed that nanocomposites, even containing very low filler loadings (i.e. 1, 3 wt%), exhibited enhanced thermomechanical properties, which seem to be connected not only to the loading, but also to the peculiar cage or ladder-like architecture of SH-NBBs.