Influence of the Composition of the Hybrid Filler on the Atomic Oxygen Erosion Resistance of Polyimide Nanocomposites

The structure and properties of nanocomposites based on organosoluble polyimide (PI) and branched functional metallosiloxane oligomers with different types of central metal atoms (Al, Cr, Fe, Zr, Hf and Nb) were investigated. Under the same weight content of the filler, the geometric parameters of the nanoparticles and thermal properties of the nanocomposites did not exhibit a direct relationship with the ability of the materials to withstand the incident flow of oxygen plasma. The atomic oxygenerosion resistance of the filled PI films was influenced by the composition of the hybrid fillerand the type of metal atom in the hybrid filler in the base metallosiloxane oligomer. To determine the effectiveness of the nanoparticles as protective elements of the polymer surface, the nanocomposite erosion yields pertaining to the concentration of the crosslinked organo–inorganic polymer forming the dispersed phase were determined and expressed in mmol per gram PI. The filler concentration in the polymer, expressed in these units, allows for comparison of the efficiency of different nanosize fillers for use in fabricating space survivable coatings. This can be important in the pursuit of new precursors, fillers for fabricating space survivable polymer composites.

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Synthesis and Characterization of New Zinc Phthalocyanine - Dodecenyl Succinic Anhydride Benzoic Groups

Current Organic Synthesis ◽

10.2174/1570179417666200519091950 ◽

2020 ◽

Vol 17 (6) ◽

pp. 488-495

Author(s):

Hussein Ali Al-Bahrani ◽

Mohanad Mousa Kareem ◽

Abdul Amir Kadhum ◽

Nour A. Alrazzak

Keyword(s):

Salicylic Acid ◽

Succinic Anhydride ◽

Zinc Phthalocyanine ◽

Central Metal ◽

Target Compound ◽

Compound I ◽

Metal Phthalocyanines ◽

Metal Atoms ◽

Amino Salicylic Acid

Background: The phthalocyanines a series of compounds involves four iso-indole units linked by aza nitrogen atoms bonded with metal atoms that are normally located in the center a phthalocyanines ring. Some of the central metal-phthalocyanines can be excited by ultraviolet light and emit a fluorescence in far-red region. Objective: To synthesize a derivative of phthalocyanines namely 4,4',4' '-tri-(dodecenyl succinic anhydride)- 4' ' '-(5-amino salicylic acid) zinc phthalocyanine with a zinc central metal. Materials and Methods: The reaction of 4- nitro Phthalonitrile and 4- amino Phthalonitrile with ZnCl2 in the presence of dimethyl amino ethanol afforded 4,4',4' '-triamino-4' ' '-nitro zinc phthalocyanine. This product reacted with 5-amino salicylic acid to yield tetra-(5-amino salicylic acid) zinc phthalocyanine. A dodecenyl succinic anhydride was added on the amine group of benzoic rings to afford 4,4',4' '-tri-(dodecenyl succinic anhydride)-4' ' '-(5-amino salicylic acid) zinc phthalocyanine(I), the target compound. Results and Discussion: Compound I is successfully synthesized with a yield of 72% from tetra-(5-amino salicylic acid) zinc phthalocyanine with dodecenyl succinic anhydride. Conclusion: The newly synthesized molecule of 4,4',4' '-tri-(dodecenyl succinic anhydride)-4' ' '-(5-amino salicylic acid) zinc phthalocyanine (I), tetra-(5-amino salicylic acid) zinc phthalocyanine(E) and 4,4',4' '- triamino-4' ' '-nitro zinc phthalocyanine (S). The reaction of 4- nitro Phthalonitrile and 4- amino and the structure of compound I is confirmed and its formation was proven.

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The Influence of the Density of CNT Arrays on Their Atomic Oxygen Erosion Effects

Journal of Physics Conference Series ◽

10.1088/1742-6596/1948/1/012209 ◽

2021 ◽

Vol 1948 (1) ◽

pp. 012209

Author(s):

Man Li ◽

Yuming Liu ◽

Yu Li ◽

Qiang Yu ◽

Yongtai Zhang ◽

...

Keyword(s):

Atomic Oxygen ◽

Cnt Arrays ◽

Atomic Oxygen Erosion

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Characterization of hybrid fillers based on carbon black of different types obtained by impregnation

Proceedings of the Institution of Mechanical Engineers Part L Journal of Materials Design and Applications ◽

10.1177/1464420715602141 ◽

2015 ◽

Vol 231 (7) ◽

pp. 584-599 ◽

Cited By ~ 2

Author(s):

Ahmed A Al-Ghamdi ◽

Omar A Al-Hartomy ◽

Falleh R Al-Solamy ◽

Nikolay Dishovsky ◽

Petrunka Malinova ◽

...

Keyword(s):

Carbon Black ◽

Inductively Coupled Plasma ◽

Total Pore Volume ◽

Silica Content ◽

Dual Phase ◽

Hybrid Filler ◽

Average Pore ◽

Hybrid Fillers ◽

Different Types ◽

Two Phases

The paper presents the investigations on obtaining dual phase fillers with preset silica content running a successful impregnation of two completely different types of conventional carbon black with silicasol. The hybrid fillers studied were characterized by atomic absorption spectroscopy and inductively coupled plasma–optical emission spectroscopy. The total pore volume, the average pore diameter, the specific surface area, the oil absorption number, and iodine adsorption of the fillers were also investigated. The distribution of both phases within the hybrid filler obtained and their interpenetration were investigated with scanning transmission electron microscopy-energy dispersive X-ray spectroscopy. The hybrid products obtained were investigated as reinforcing fillers of natural rubber-based composites. The results obtained show that the suggested impregnation with silicasol of conventional carbon black is a perspective method for preparation of carbon-silica dual phase fillers. The method provides an easy control over the quantitative ratio between the two phases. The fillers thus prepared do not change significantly the curing and mechanical characteristics of the vulcanizates, but improve their thermal aging resistance. The isolation of the carbon black aggregates by the silica phase, and the interpenetration of the two phases is a prerequisite to obtain elastomer composites of good mechanical and microwave properties suitable for producing of microwave shielding devices.

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Vacuum Ultraviolet/Atomic Oxygen Erosion Resistance of Amorphous Si0.26C0.43N0.31 Coating

Journal of Spacecraft and Rockets ◽

10.2514/1.38391 ◽

2011 ◽

Vol 48 (3) ◽

pp. 507-512 ◽

Cited By ~ 3

Author(s):

L. F. Hu ◽

M. S. Li ◽

J. J. Xu ◽

Ziqi Sun ◽

Y. C. Zhou

Keyword(s):

Atomic Oxygen ◽

Vacuum Ultraviolet ◽

Erosion Resistance ◽

Atomic Oxygen Erosion

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Space Atomic Oxygen Erosion Effects on Epoxy and Silicone Adhesives Used in LEO Spacecraft

10.1063/1.3076889 ◽

2009 ◽

Author(s):

Li Tao ◽

Jiang Lixiang ◽

Feng Weiquan ◽

Liu Xiangpeng ◽

Jacob I. Kleiman

Keyword(s):

Atomic Oxygen ◽

Atomic Oxygen Erosion

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Hybrid Precipitated Calcium Carbonate Containing Wood Flour for Paper Applications – A Comparative Handsheet Study

Chemical Science International Journal ◽

10.9734/csji/2019/v27i230110 ◽

2019 ◽

pp. 1-13

Author(s):

Klaus Dölle ◽

Kilian F. Baumgartner ◽

Neil F. Goodman ◽

Alexander Klitsiotisoris

Keyword(s):

Calcium Carbonate ◽

Filler Content ◽

Wood Flour ◽

Filler Material ◽

Carbonate Mineral ◽

Precipitated Calcium Carbonate ◽

Hybrid Filler ◽

Different Types ◽

Flour Blends ◽

Ground Calcium Carbonate

The main objective of this paper handsheet study is to investigate if a hybrid filler material containing wood flour and precipitated calcium carbonate can replace and/or supplement commercially available ground calcium carbonate and precipitated calcium carbonate mineral filler material for papermaking. The handsheet study contains 25 different furnish mixtures. Four different types of wood flour were used to manufacture the hybrid filler material, including two wood flour blends with a strengthening agent. All handsheet were manufactured with an 80% harwood and 20% softwood mix. The filler content varied between 10, 15 and 20%. The study showed that the hybrid filler material achieved a retention of up to 92.68% as well as a higher caliper of up to 208 μm compared to commercial ground and precipitated calcium carbonate of 120.4 μm and 145.6 μm respectively. Tensile and tear strength did not show an improvement. Elongation and tensile energy absorption did improve of up to 30% with the strength additive containing hybrid filler material. Opacity was improved of up to 10% with the hybrid filler material. Brightness and color values were lower due to the natural brow color of the wood flower material.

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FORMATION OF COMBINED SURFACE FEATURES OF PROTRUSION ARRAY AND WRINKLES ATOP SHAPE-MEMORY POLYMER

Surface Review and Letters ◽

10.1142/s0218625x09013505 ◽

2009 ◽

Vol 16 (06) ◽

pp. 929-933 ◽

Cited By ~ 16

Author(s):

L. SUN ◽

Y. ZHAO ◽

W. M. HUANG ◽

T. H. TONG

Keyword(s):

Shape Memory ◽

Shape Memory Polymer ◽

Polymer Surface ◽

Cost Effective ◽

Gold Layer ◽

Surface Features ◽

Cost Effective Approach ◽

Different Types ◽

Sputter Deposited ◽

Steel Balls

We demonstrate a simple and cost-effective approach to realize two combined surface features of different scales together, namely submillimeter-sized protrusion array and microwrinkles, atop a polystyrene shape-memory polymer. Two different types of protrusions, namely flat-top protrusion and crown-shaped protrusion, were studied. The array of protrusions was produced by the Indentation-Polishing-Heating (IPH) process. Compactly packed steel balls were used for making array of indents. A thin gold layer was sputter deposited atop the polymer surface right after polishing. After heating for shape recovery, array of protrusions with wrinkles on the top due to the buckling of gold layer was produced.

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Mossbauer studies in transition metal chemistry. III. Compounds of iron with some sulphur-containing Schiff base ligands

Australian Journal of Chemistry ◽

10.1071/ch9742307 ◽

1974 ◽

Vol 27 (11) ◽

pp. 2307 ◽

Cited By ~ 10

Author(s):

M Bond ◽

RL Martin ◽

IAG Roos

Keyword(s):

Schiff Base ◽

Tridentate Ligand ◽

Coordinate Structure ◽

Schiff Base Ligands ◽

Tridentate Ligands ◽

Cubic Symmetry ◽

Field Gradients ◽

Metal Atoms ◽

Different Types ◽

Local Symmetries

M�ssbauer spectra are reported for a series of iron complexes with sulphur-containing Schiff base ligands. These tridentate ligands are based on the Schiff base formed by the condensation of dithiocarbazic acid and pyridine-2-carbaldehyde and form complexes with a metal-to-ligand ratio of 1 : 1 and 1 : 2. The M�ssbauer study confirms that most of these complexes contain iron(11) with examples of both high-and low-spin and one example of a spin crossover. Several iron(111) complexes were also studied. The quadrupole splittings show the anisotropy in bonding expected for metal atoms coordinated to different types of atoms within the same chelate ring. However, for some complexes the splittings are small, showing that low local symmetries need not produce large electric field gradients. In cases where it is applicable, the temperature dependence of the quadrupole splitting has been used to derive a splitting of the t2 and e orbitals produced by the non-cubic symmetry. For compounds of the form Fe(L)X2, where X is a halide and L the tridentate ligand, the Mossbauer results are best interpreted in terms of a five-coordinate structure rather than a six-coordinate bridged dimer.

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