Low-dielectric-constant benzocyclobutene-organosilicon resins constructed from cyclotetrasiloxane

High Thermal Stability and Low Dielectric Constant of BCB Modified Silicone Resins

Based on the excellent physical properties and flexible molecular modifiability, modified silicone resins have received favorable attention in the field of microelectronics, and recently a number of modified silicone resins have appeared while few breakthroughs have been made in low dielectric constant (low-k) materials field due to the limitations of structure or the curing process. In this work, functional silicone resin with different BCB contents was prepared with two monomers. The resins showed low dielectric constant (k = 2.77 at 10 MHz) and thermal stability (T_5% = 495.0 °C) after curing. Significant performance changes were observed with the increase in BCB structural units, and the functional silicone obtained does not require melting and dissolution during processing because of good fluidity at room temperature. Moreover, the mechanical properties of silicone resins can be also controlled by adjusting the BCB content. The obtained silicone resins could be potentially used in the field of electronic packaging materials.

Thermo-curable and photo-patternable polysiloxanes and polycarbosiloxanes by a facile Piers–Rubinsztajn polycondensation and post-modification

A series of BCB-functionalized organosilicon materials were prepared by a facile Piers–Rubinsztajn polycondensation and Heck coupling post-modification method, rendering a simple and efficient option for advanced packaging dielectric materials.

A transparent cyclo-linear polyphenylsiloxane elastomer integrating high refractive index, thermal stability and flexibility

A cyclo-linear structured transparent polyphenylsiloxane elastomer combining high refractive index, high thermal stability and superior flexibility was prepared by a one-pot hydrosilylation reaction.

A fluoropolymer with a low dielectric constant at a high frequency derived from bio-based anethole

The copolymerization between a fluoro-containing monomer derived from bio-based anethole and a benzocyclobutene (BCB)-containing monomer gave a polymer with good dielectric properties and low water uptake.

Experimental and Theoretical Investigation of Excited-State Intramolecular Proton Transfer Processes of Benzothiazole Derivatives in Amino-polydimethylsiloxanes before and after Cross-Linking by CO2

The changes in the ability of three fluorescent derivatives of 2-(2'-hydroxyphenyl)benzothiazole to undergo excited-state intramolecular proton transfer (ESIPT) processes have been correlated with the rheological properties of four amino-polydimethylsiloxanes with different molar masses and containing different amounts of monomer units with amino pendant groups, in the presence and absence of a cross-linking molecule, CO₂. The changes lead to a variety of species (keto, enol, and enolate forms) in both the ground and excited states. Calculations using the density-functional theory/time-dependent density-functional theory method at the CAM-B3LYP/6-311++G(d,p) level helped to identify how ESIPT is involved in the formation of the intermediates. The results demonstrate that proton transfer in 2-(2'-hydroxyphenyl)benzothiazoles is a powerful tool to identify local changes in the viscosity and micropolarity of the environment that are attributed to the structural differences of the amino-polydimethylsiloxanes and their cross-linking.