Functional Polyimide/Polyhedral Oligomeric Silsesquioxane Nanocomposites

Abstract

The preparation of hybrid nanocomposite materials derived from polyhedral oligomeric silsesquioxane (POSS) nanoparticles and polyimide (PI) has recently attracted much attention from both academia and industry, because such materials can display low water absorption, high thermal stability, good mechanical characteristics, low dielectric constant, flame retardance, chemical resistance, thermo-redox stability, surface hydrophobicity, and excellent electrical properties. Herein, we discussed the various methods that have been used to insert POSS nanoparticles into PI matrices, through covalent chemical bonding and physical blending, as well as the influence of the POSS units on the physical properties of the PIs.

Keywords: dielectric constant; double-decker-shaped silsesquioxane (DDSQ); polyhedral oligomeric silsesquioxane (POSS); polyimide; thermal stability.

Figure 1

Schematic representation of possible architectures for incorporation of polyhedral oligomeric silsesquioxanes (POSS) nanoparticles (NPs) into polymer matrices [2]. Reproduced with permission from Elsevier.

Figure 2

Cartoon representation of the deformation processes of Polyimide (PI)/octakis(dimethylsiloxyhexafluoropropyl) silsesquioxane (OF)-POSS and (OP)-POSS NPs during imidization [71]. Reproduced with permission from Wiley.

Figure 3

(a) Chemical structure of octa(aminophenyl)silsesquioxane (OAPS). (b) Schematic representation of the preparation of OAPS-graphene oxide (GO)/PI hybrid nanocomposites [74]. Reproduced with permission from the American Chemical Society.

Figure 4

(a) Stress–strain curves of neat PI films and OAPS-GO/PI films with different contents of various amounts of OAPS-GO. (b) Profile dielectric constants of neat PI films, GO/PI films, and OAPS-GO/PI films [74]. Reproduced with permission from the American Chemical Society.

Figure 5

Dynamic mechanical analysis (DMA) curves for (a,c) pure PI and (b,d) porous PI (obtained from 10 wt % PEO-POSS), recorded at a heating rate of 2 °C/min [75]. Reproduced with permission from Elsevier.

Figure 6

Preparation of (a) poly(amic acid) (PAA); (b) PAA/POSS nanocomposites; and (c) PI linked through its chain ends to POSS [76]. Reproduced with permission from the American Chemical Society.

Figure 7

Synthesis of fluorinated PI/POSS hybrid nanocomposites [77]. Reproduced with permission from Springer.

Figure 8

Schematic representation of side chain-tethered PI/POSS nanocomposites [78]. Reproduced with permission from the American Chemical Society.

Figure 9

Preparation of semi-aromatic PIs containing a double-decker-shaped silsesquioxane (DDSQ) in the main chain [80]. Reproduced with permission from the American Chemical Society.

Figure 10

(a) Thermogravimetric analysis (TGA) thermogram and (b) water contact angles of PIs containing various contents of 5,11,14,17-tetranilino DDSQ [81]. Reproduced with permission from Wiley.

Figure 11

TEM micrographs of the synthesis of PIs containing various contents of 5,11,14,17 tetranilino DDSQ [81]. Reproduced with permission from Wiley.

Figure 12

Preparation of organic/inorganic PIs with DDSQ in the main chain [82]. Reproduced with permission from the Royal Society of Chemistry.

Figure 13

Plots of dielectric constant of organic/inorganic PIs with DDSQ in the main chain [82]. Reproduced with permission from the Royal Society of Chemistry.

Figure 14

Preparation of OG-POSS cross-linked PIs [83]. Reproduced with permission from Elsevier.

Figure 15

Preparation of POSS cross-linked cross-linked sulfonated PIs (SPIs) [84]. Reproduced with permission from Elsevier.

Figure 16

Schematic representation of PI cross-linked POSS [85]. Reproduced with permission from Elsevier.

Figure 17

Preparation of star POSS/PI hybrid materials [86]. Reproduced with permission from Elsevier.