scholarly journals Development of Cycloaliphatic Epoxy-POSS Nanocomposite Matrices with Enhanced Resistance to Atomic Oxygen

Molecules ◽  
2020 ◽  
Vol 25 (7) ◽  
pp. 1483 ◽  
Author(s):  
Mayra Y. Rivera Lopez ◽  
Javier Martin Lambas ◽  
Jonathan P. Stacey ◽  
Sachithya Gamage ◽  
Agnieszka Suliga ◽  
...  
Keyword(s):  
Atomic Oxygen ◽  
Low Earth Orbit ◽  
Cfrp Laminates ◽  
Cycloaliphatic Epoxy ◽  
Enhanced Resistance ◽  
Environment Exposure ◽  
Before And After ◽  
Cycloaliphatic Epoxy Resin ◽  
Out Of Autoclave ◽  
Oligomeric Silsesquioxane

The preparation of ultra-thin CFRP laminates, which incorporate a cycloaliphatic epoxy resin reinforced with polyhedral oligomeric silsesquioxane (POSS) reagent nanofiller, using out-of-autoclave procedure is reported. The influence of the amount of POSS within the laminate on the mechanical properties and surface roughness of the laminates is analysed before and after exposure to atomic oxygen (AO) to simulate the effects of low Earth orbit (LEO). The addition of 5 wt% POSS to the base epoxy leads to an increase in both flexural strength and modulus, but these values begin to fall as the POSS content rises, possibly due to issues with agglomeration. The addition of POSS offers improved resistance against AO degradation with the laminates containing 20 wt% POSS demonstrating the lowest erosion yield (1.67 × 10−24 cm2/atom) after the equivalent of a period of 12 months in a simulated LEO environment. Exposure to AO promotes the formation of a silicon-rich coating layer on the surface of the laminate, which in turn reduces roughness and increases stiffness, as evidenced by measurements of flexural properties and spectral data after exposure.

Atomic oxygen effects on polymers containing silicon or phosphorus: Mass loss, erosion yield, and surface morphology

2018 ◽  
Vol 31 (8) ◽  
pp. 969-976 ◽  
Author(s):  
Wang Chunbo ◽  
Jiang Haifu ◽  
Tian Dongbo ◽  
Qin Wei ◽  
Chen Chunhai ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Mass Loss ◽  
Atomic Oxygen ◽  
Low Earth Orbit ◽  
Relative Order ◽  
Oxygen Effects ◽  
Arylene Ether ◽  
Inorganic Coatings ◽  
Oligomeric Silsesquioxane ◽  
Surface Morphologies

The differences among polymers containing silicon or phosphorus, 20% polyhedral oligomeric silsesquioxane polyimide (20%-POSS-PI), 30% polysiloxane- block-polyimides (30%-PSX-PI), poly(siloxane imide) homopolymer (PSX-PI), and arylene ether phosphine oxide homopolymer (P-PPO), on mass loss, erosion yield, and surface morphology were elucidated. The tolerance against atomic oxygen (AO) was improved versus Kapton®H after introducing silicon or phosphorus to the polymers. The relative order of the mass loss was PSX-PI < P-PPO < 20%-POSS-PI < 30%-PSX-PI. In contrast, the erosion yields of 30%-PSX-PI, 20%-POSS-PI, and P-PPO decreased by orders of magnitude (PSX-PI declined by about two orders). The surface of Kapton®H was seriously eroded by AO exhibiting a “carpet-like” shape, and the roughness of the surface of Kapton®H became remarkable as the AO fluence increased. PSX-PI, P-PPO, 20%-POSS-PI, and 30%-PSX-PI at an AO fluence of 5.2 × 1020 atoms/cm2 had different surface morphologies, and the relative order of the surface roughness was PSX-PI < 30%-PSX-PI < 20%-POSS-PI < P-PPO. The 30%-PSX-PI and PSX-PI had minor mass losses and a smooth surface. This kind of material might replace inorganic coatings for applications in low earth orbit.

Changes in Tribological Properties of MoS2 Film Exposed to LEO on SM/SEED

2005 ◽  
Author(s):  
Koji Matsumoto ◽  
Masao Akiyama ◽  
Masahito Tagawa ◽  
Kichiro Imagawa
Keyword(s):  
Atomic Oxygen ◽  
Space Station ◽  
Experimental System ◽  
Low Earth Orbit ◽  
Space Environment ◽  
Ultraviolet Rays ◽  
Low Friction ◽  
Environment Exposure ◽  
Mos2 Film ◽  
One Year

Service Module / Space Environment Exposure Device (SM/SEED) is experimental system aboard International Space Station (ISS) to evaluate the degradation of various materials for space application under the Low Earth orbit (LEO) space environment. Three sets of exposure pallets of SM/SEED with the same samples have been exposed to LEO since October 2001. One of the pallets returned to Earth after about one-year exposure. A bonded molybdenum disulfide (MoS2) film was also exposed as a tested material of SM/SEED. The changes in tribological characteristics of the film were examined. And effects of ground-based irradiation with LEO environmental factors (e.g., Atomic Oxygen (AO) and Ultraviolet rays (UV)) were also evaluated. At the beginning of the test, low friction coefficient was observed both in the flight and the AO-irradiated samples. MoO3 was detected from the surface of these samples. A large amount of SiO2 was recognized from the flight sample.

scholarly journals Self-Healing Anti-Atomic-Oxygen Phosphorus-Containing Polyimide Film via Molecular Level Incorporation of Nanocage Trisilanolphenyl POSS: Preparation and Characterization

Polymers ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1013 ◽  
Author(s):  
Bohan Wu ◽  
Yan Zhang ◽  
Dayong Yang ◽  
Yanbin Yang ◽  
Qiang Yu ◽  
...  
Keyword(s):  
Atomic Oxygen ◽  
Composite Films ◽  
Polymeric Materials ◽  
Polyimide Film ◽  
Low Earth Orbit ◽  
Nanocomposite Films ◽  
Self Healing ◽  
Passivation Layers ◽  
Pyromellitic Anhydride ◽  
Oligomeric Silsesquioxane

Protection of polymeric materials from the atomic oxygen erosion in low-earth orbit spacecrafts has become one of the most important research topics in aerospace science. In the current research, a series of novel organic/inorganic nanocomposite films with excellent atomic oxygen (AO) resistance are prepared from the phosphorous-containing polyimide (FPI) matrix and trisilanolphenyl polyhedral oligomeric silsesquioxane (TSP–POSS) additive. The PI matrix derived from 2,2’-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) and 2,5-bis[(4-amino- phenoxy)phenyl]diphenylphosphine oxide (BADPO) itself possesses the self-healing feature in AO environment. Incorporation of TSP–POSS further enhances the AO resistance of the FPI/TSP composite films via a Si–P synergic effect. Meanwhile, the thermal stability of the pristine film is maintained. The FPI-25 composite film with a 25 wt % loading of TSP–POSS in the FPI matrix exhibits an AO erosion yield of 3.1 × 10−26 cm3/atom after an AO attack of 4.0 × 1020 atoms/cm2, which is only 5.8% and 1.0% that of pristine FPI-0 film (6FDA-BADPO) and PI-ref (PMDA-ODA) film derived from 1,2,4,5-pyromellitic anhydride (PMDA) and 4,4’-oxydianline (ODA), respectively. Inert phosphorous and silicon-containing passivation layers are observed at the surface of films during AO exposure.

Improved atomic oxygen erosion resistance of the carbon fibre–epoxy interface with polyhedral oligomeric silsesquioxane

2020 ◽  
Vol 32 (6) ◽  
pp. 681-692 ◽  
Author(s):  
Dan Zhao ◽  
Jinmei He ◽  
Nan Zheng ◽  
Yudong Huang
Keyword(s):  
Carbon Fibre ◽  
Photoelectron Spectroscopy ◽  
Atomic Oxygen ◽  
Erosion Resistance ◽  
Polyhedral Oligomeric Silsesquioxane ◽  
Low Earth Orbit ◽  
Siloxane Oligomers ◽  
Interlaminar Shear ◽  
Oligomeric Silsesquioxane ◽  
Atomic Oxygen Erosion

Polyhedral oligomeric silsesquioxane (POSS) was grafted onto the surface of carbon fibres (CFs) to fabricate carbon fibre/epoxy (CF/EP) composites with improved interlaminar shear strength (ILSS) and atomic oxygen (AO) erosion resistance. POSS-CF was prepared by reacting amine groups on the pretreated CF surface with the POSS to form a continuous uniform layer of siloxane oligomers. X-Ray photoelectron spectroscopy, scanning electron microscopy and Fourier transform infrared spectroscopy demonstrated that POSS was successfully grafted onto the CF surface. The ILSS and AO erosion resistance of the POSS-treated CFs and CF-EP interface were improved because a SiO2 passivation layer formed with AO exposure, especially with POSS-EP0409. This is an effective solution for enhancing the interfacial bonding force and interfacial AO erosion resistance for the low-Earth orbit environment.

scholarly journals Influence of POSS Type on the Space Environment Durability of Epoxy-POSS Nanocomposites

Nanomaterials ◽  
2022 ◽  
Vol 12 (2) ◽  
pp. 257
Author(s):  
Avraham I. Bram ◽  
Irina Gouzman ◽  
Asaf Bolker ◽  
Nurit Atar ◽  
Noam Eliaz ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Atomic Oxygen ◽  
Low Earth Orbit ◽  
Space Environment ◽  
Space Applications ◽  
Polymer Backbone ◽  
X Ray ◽  
Total Mass Loss ◽  
Oligomeric Silsesquioxane ◽  
Potential Use

In order to use polymers at low Earth orbit (LEO) environment, they must be protected against atomic oxygen (AO) erosion. A promising protection strategy is to incorporate polyhedral oligomeric silsesquioxane (POSS) molecules into the polymer backbone. In this study, the space durability of epoxy-POSS (EPOSS) nanocomposites was investigated. Two types of POSS molecules were incorporated separately—amine-based and epoxy-based. The outgassing properties of the EPOSS, in terms of total mass loss, collected volatile condensable material, and water vapor regain were measured as a function of POSS type and content. The AO durability was studied using a ground-based AO simulation system. Surface compositions of EPOSS were studied using high-resolution scanning electron microscopy and X-ray photoelectron spectroscopy. It was found that with respect to the outgassing properties, only some of the EPOSS compositions were suitable for the ultrahigh vacuum space environment, and that the POSS type and content had a strong effect on their outgassing properties. Regardless of the POSS type being used, the AO durability improved significantly. This improvement is attributed to the formation of a self-passivated AO durable SiO2 layer, and demonstrates the potential use of EPOSS as a qualified nanocomposite for space applications.

Effect of Atomic Oxygen Exposure on Polyhedral Oligomeric Silsesquioxane/Polyimide Hybrid Materials in Low Earth Orbit Environment

2011 ◽  
Vol 492 ◽  
pp. 521-524 ◽  
Author(s):  
Shu Wang Duo ◽  
Mi Mi Song ◽  
Ting Zhi Liu ◽  
Chang Yuan Hu ◽  
Mei Shuan Li
Keyword(s):  
Photoelectron Spectroscopy ◽  
Atomic Oxygen ◽  
Polyhedral Oligomeric Silsesquioxane ◽  
Surface Region ◽  
Low Earth Orbit ◽  
Hybrid Films ◽  
Sem Images ◽  
Near Surface ◽  
X Ray ◽  
Oligomeric Silsesquioxane

A novel polyimide (PI) hybrid nanocomposite containing polyhedral oligomeric silsesquioxane (POSS) had been prepared by copolymerization of octa(aminophenyl)silsesquioxane (OAP-POSS), 4,4’ -oxydianiline (ODA), and pyromellitic dianhydride (PMDA). The AO resistance of these POSS/PI hybrid films was tested in the ground-based AO simulation facility. Exposed and unexposed surfaces have been characterized by X-ray photoelectron spectroscopy and FTIR. The XPS data indicate that the carbon content of the near-surface region is decreased from 63.6 to 19.3 at% after AO exposure. The oxygen and silicon concentrations in the near-surface region increase after AO exposure. The data reveal the formation of a passive inorganic SiO2 layer on the POSS/PI hybrid films during the AO exposure, which serves as a protective barrier preventing further degradation of the underlying polymer with increased exposure to the AO flux. SEM images showed that the surface of the 10 wt% POSS/PI became much less rough than that of the pristine polyimide. The AO resistance of the POSS/PI hybrid films is up to several tenfold than that of the pristine polyimide.

scholarly journals Atomic Oxygen-Resistant Polyimide Composite Films Containing Nanocaged Polyhedral Oligomeric Silsesquioxane Components in Matrix and Fillers

Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 141
Author(s):  
Yan Zhang ◽  
Hao Wu ◽  
Yi-dan Guo ◽  
Yan-bin Yang ◽  
Qiang Yu ◽  
...  
Keyword(s):  
High Temperature ◽  
Atomic Oxygen ◽  
Composite Films ◽  
Linear Thermal Expansion ◽  
Polyhedral Oligomeric Silsesquioxane ◽  
Low Earth Orbit ◽  
Aromatic Diamine ◽  
Self Healing ◽  
Passivation Layers ◽  
Oligomeric Silsesquioxane

For the development of spacecraft with long-servicing life in low earth orbit (LEO), high-temperature resistant polymer films with long-term atomic oxygen (AO) resistant features are highly desired. The relatively poor AO resistance of standard polyimide (PI) films greatly limited their applications in LEO spacecraft. In this work, we successfully prepared a series of novel AO resistant PI composite films containing nanocaged polyhedral oligomeric silsesquioxane (POSS) components in both the PI matrix and the fillers. The POSS-containing PI matrix film was prepared from a POSS-substituted aromatic diamine, N-[(heptaisobutyl-POSS)propyl]-3,5-diaminobenzamide (DABA-POSS) and a common aromatic diamine, 4,4′-oxydianline (ODA) and the aromatic dianhydride, pyromellitic dianhydride (PMDA) by a two-step thermal imidization procedure. The POSS-containing filler, trisilanolphenyl POSS (TSP-POSS) was added with the fixed proportion of 20 wt% in the final films. Incorporation of TSP-POSS additive apparently improved the thermal stability, but decreased the high-temperature dimensional stable nature of the PI composite films. The 5% weight loss temperature (T5%) of POSS-PI-20 with 20 wt% of DABA-POSS is 564 °C, and its coefficient of linear thermal expansion (CTE) is 81.0 × 10−6/K. The former is 16 °C lower and the latter was 20.0 × 10−6/K higher than those of the POSS-PI-10 film (T5% = 580 °C, CTE = 61.0 × 10−6/K), respectively. POSS components endowed the PI composite films excellent AO resistance and self-healing characteristics in AO environments. POSS-PI-30 exhibits the lowest AO erosion yield (Es) of 1.64 × 10−26 cm3/atom under AO exposure with a flux of 2.51 × 1021 atoms/cm2, which is more than two orders of magnitude lower than the referenced PI (PMDA-ODA) film. Inert silica or silicate passivation layers were detected on the surface of the PI composite films exposed to AO.

scholarly journals Preparation and Properties of Intrinsically Atomic-Oxygen Resistant Polyimide Films Containing Polyhedral Oligomeric Silsesquioxane (POSS) in the Side Chains

Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2865 ◽  
Author(s):  
Hao Wu ◽  
Yan Zhang ◽  
Yi-Dan Guo ◽  
Hao-Ran Qi ◽  
Yuan-Cheng An ◽  
...  
Keyword(s):  
Atomic Oxygen ◽  
Linear Thermal Expansion ◽  
Polyhedral Oligomeric Silsesquioxane ◽  
Tensile Modulus ◽  
Low Earth Orbit ◽  
Molecular Structures ◽  
Polyimide Films ◽  
Passivation Layers ◽  
Pyromellitic Anhydride ◽  
Oligomeric Silsesquioxane

The relatively poor atomic-oxygen (AO) resistance of the standard polyimide (PI) films greatly limits the wide applications in low earth orbit (LEO) environments. The introduction of polyhedral oligomeric silsesquioxane (POSS) units into the molecular structures of the PI films has been proven to be an effective procedure for enhancing the AO resistance of the PI films. In the current work, a series of POSS-substituted poly (pyromellitic anhydride-4,4′-oxydianiline) (PMDA-ODA) films (POSS-PI) with different POSS contents were synthesized via a POSS-containing diamine, N-[(heptaisobutyl-POSS)propyl]-3,5-diaminobenzamide (DABA-POSS). Subsequently, the effects of the molecular structures on the thermal, tensile, optical, and especially the AO-erosion behaviors of the POSS-PI films were investigated. The incorporation of the latent POSS substituents decreased the thermal stability and the high-temperature dimensional stability of the pristine PI-0 (PMDA-ODA) film. For instance, the PI-30 film with the DABA-POSS content of 30 wt% in the film exhibited a 5% weight loss temperature (T5%) of 512 °C and a coefficient of linear thermal expansion (CTE) of 54.6 × 10−6/K in the temperature range of 50–250 °C, respectively, which were all inferior to those of the PI-0 film (T5% = 574 °C; CTE = 28.9 × 10−6/K). In addition, the tensile properties of the POSS-containing PI films were also deteriorated, to some extent, due to the incorporation of the DABA-POSS components. The tensile strength (TS) of the POSS-PI films decreased with the order of PI-0 > PI-10 > PI-15 > PI-20 > PI-25 > PI-30, and so did the tensile modulus (TM) and the elongations at break (Eb). PI-30 showed the TS, TM, and Eb values of 75.0 MPa, 1.55 GPa, and 16.1%, respectively, which were all lower than those of the PI-0 film (TS = 131.0 MPa, TM = 1.88 GPa, Eb = 73.2%). Nevertheless, the incorporation of POSS components obviously increased the AO resistance of the PI films. All of the POSS-PI films survived from the AO exposure with the total fluence of 2.16 × 1021 atoms/cm2, while PI-0 was totally eroded under the same circumstance. The PI-30 film showed an AO erosion yield (Es) of 1.1 × 10−25 cm3/atom, which was approximately 3.67% of the PI-0 film (Es = 3.0 × 10−24 cm3/atom). Inert silica or silicate passivation layers were detected on the surface of the POSS-PI films after AO exposure, which efficiently prevented the further erosion of the under-layer materials.

Hyperthermal atomic oxygen durable transparent silicon-reinforced polyimide

2018 ◽  
Vol 31 (7) ◽  
pp. 831-842 ◽  
Author(s):  
Min Qian ◽  
Xiao Yang Xuan
Keyword(s):  
Surface Morphology ◽  
Atomic Oxygen ◽  
Polyhedral Oligomeric Silsesquioxane ◽  
Amic Acid ◽  
Low Earth Orbit ◽  
Element Composition ◽  
Earth Orbit ◽  
Promising Candidate ◽  
Direct Dissolution ◽  
Oligomeric Silsesquioxane

A clear poly(amic acid) was reinforced by a trisilanolphenyl polyhedral oligomeric silsesquioxane (POSS) by direct dissolution, and transparent silicon-reinforced polyimide (Si-RPI) films with different POSS loadings were obtained after curing, showing high transmittance of >90% within 380–800 nm. The Si-RPI films were exposed to a ground hyperthermal atomic oxygen (AO) beam. The erosion depths and derived erosion yields of the materials decreased with POSS loadings. At a 20 wt% POSS loading, the Si-RPI showed an erosion yield of 0.13 × 10−24 cm3 atom−1 at a fluence of 2.79 × 1020 O atoms cm−2. Surface morphology and element composition characterization on Si-RPI indicated that SiOx-based passivating layers were formed on surfaces upon the hyperthermal AO attack. This study suggests a facile way of reinforcing Si into transparent polyimide for a promising candidate of spacecraft coating material operating in low Earth orbit.

Sign in / Sign up

Export Citation Format

Share Document