Polyhedral oligomeric silsesquioxane polyimide nanocomposites for color filters and flexible conductive films

Abstract

Color filters and conductive films are widely used in spacecraft, while the lack of lightweight, flexibility, and atomic oxygen (AO) durability confine their potential applications in low earth orbit. In this study, a clear poly(amic acid) with an empirical 20 wt% polyhedral oligomeric silsesquioxane (POSS) solid content is designed for transparency and AO durability. Red, green, blue, and yellow dyes are reinforced with small amounts of 1–5 wt% in POSS polyimides for color filters. A silver nanowire network film is infiltrated onto the POSS polyimide for conductive film. Erosion depth upon hyperthermal AO exposure, surface morphology, surface chemistry, optical transparency, and conductivity have been systematically investigated. The erosion yields of all 20 wt% POSS polyimides decrease by an order of magnitude when subjected to 2.32 ± 0.05 and 2.39 ± 0.06 × 1020 atoms cm−2 AO fluences, as passivating SiOx networks are formed on film surface. The small‐amount dye additives into polyimides do not introduce obvious changes in AO durability and surface chemistry. The silver nanowire infiltrated POSS polyimide film shows a 65.7% transmittance at 550 nm and a sheet resistance of 8.50 ± 0.36 Ohm square−1. This study reveals promising attempts of POSS‐polyimide‐based color filters and flexible conductive films for potential space applications.

Gas-Permeable Carbon Molecular Sieve Membranes Fabricated from a Norbornene-Functionalized Polyimide–Polyhedral Oligomeric Silsesquioxane Composite

“…Owing to the synergistic combination of POSS and PI moieties, POSS–PI composites have attracted considerable attention for various applications because of their distinctive properties, such as their excellent thermal and mechanical stability. ,− POSS–PI composites have recently been applied in systems such as electrical insulators, thermal shields, ,, solar cells, color filters, conductive films, and separation membranes. − Particularly, POSS–PI composite membranes exhibiting different configurations have been studied. For instance, Dasgupta et al and Iyer et al investigated the gas transport properties of aminoethylaminopropylisobutyl–POSS- and octaamino–POSS-embedded PI-mixed matrix membranes, respectively, in which functionalized POSS nanoparticles served as nanofillers in the PI superstructure, leading to macroscopic interactions.…”

Intrinsically Colored Polyimide Films Prepared by Embedding Chromophores on the Polymer Backbones

“…[11] Adding colorants is the most widely used method to prepare colored PIs at present, mainly including pigment-dispersed PIs and dyed PIs, which are prepared by dispersing pigments or dyes with different colors into PIs, respectively. [12] Pigmentdispersed PIs utilize pigments with excellent light and heat stability and chemical resistance as colorants. [13][14][15] However, this results in heterogeneous mixtures, and aggregation of pigment particles can easily lead to optical defects, such as reduced light transmission and contrast.…”

DC Surface Flashover Characteristics of Polyimide Containing Polyhedral Oligomeric Silsesquioxane (POSS) in the Main Chains under Vacuum

“…According to statistics, when the insulation system of the superconducting magnet fails, the polyimide as its insulating structure will have discharge phenomena such as surface flashover or even body breakdown, which is one of the main reasons for the failure of superconducting magnets [2]. When polyimide is used as an insulating material in a spacecraft, due to the combined effects of the rapid transformation and gradient distribution of high and low temperatures in space, high-energy charged particles, atomic oxygen [3], and the plasma environment, these external incentives will eventually lead to the phenomenon of surface flashover discharge in the aerospace environment of the polyimide insulating medium, and its insulating properties will be seriously damaged, which will lead to the failure of spacecraft components [4,5]. Therefore, to ensure the operational reliability of polyimide insulating materials in the fields of power systems, low-temperature superconducting devices, and aerospace, the academia and industry circles hope to improve the surface flashover characteristics of polyimide in vacuum through functional modification and other means.…”