Polyimide-Side-Chain Tethered Polyhedral Oligomeric Silsesquioxane Nanocomposites for Low-Dielectric Film Applications

Abstract

Low-dielectric-constant nanoporous films (dielectric constant, k = 2.4) with thermal integrity and controllable mechanical strength have been prepared by covalently tethering nanoporous polyhedral oligomeric silsesquioxane (POSS) molecules, 1-nm size, to the side chains of polyimide. The tethered POSS molecules in the amorphous polyimide retain a nanoporous crystal structure, but form an additional ordered architecture due to microphase separation. With this approach, the dielectric constant of the film can be tuned by the amount of POSS molecules introduced in the nanocomposite film; the polyimide molecules offer additional advantages of maintaining certain thermal and mechanical strengths.

Novel elastomer dye-functionalised POSS nanocomposites: Enhanced colourimetric, thermomechanical and thermal properties

“…Verker et al [30] and Zhao and Schiraldi [31] attributed similar behaviour to a disruption of the polymer molecular (chain) structure brought on by POSS concentrations above 5 wt%. Liu and Zheng [32] suggested this observation is caused by a decrease in material density, due to an increase in nanocomposite porosity [33,34]. Additionally, the crosslinking densities per unit volume can decrease with increasing POSS content, compromising the reinforcement mechanism as a consequence.…”

Synthesis and characterization of flexible and high-temperature resistant polyimide aerogel with ultra-low dielectric constant

“…By this methodology, various ultra low-k PIs have been reported [10][11][12][13][14]. However, the attempts further reducing the k values of PIs below 1.5 seem to be more challenging because the conventional methods could only achieve a very limited air loading (<60%, volume ratio).…”

Selective Vinyl Functionalization of Octakis(dimethylsiloxy)octasilsesquioxane with Allylbenzene and 1,5-Hexadiene and Copolymerization of the Products with Bis(dimethylsilyl)benzene

“…It has nanometer-size cubic structure with wide surface area and controlled porosity, and can be functionalized with a wide variety of organic groups as monomer in a typical polymerization. Use of POSS derivatives as monomer has been demonstrated to be an efficient method in the design of nanocomposite materials [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] as well as in designing various hybrid polymers with POSS as side groups [16][17][18][19][20][21][22][23][24][25][26][27][28] or as chain end, [29][30][31] which exhibit desirable unique properties. Laine et al reported the synthesis of multi-functinal POSS as precursors of nanocomposite materials from commercially available typical silane-functionalized cubic silsesquioxane, octakis(dimethylsiloxy)octasilsesquioxane (Q 8 M 8 H ) by hydrosilylation.…”