Toughening phenolic composite laminates by interleaving hybrid pyrolytic carbon/polyvinyl butyral nanomat

The objectives of this study are to evaluate the internal damage and compressive residual strength of composite laminate by impact loading. To investigate the environmental effects, as-received and accelerated-aged glass/phenolic laminates are used. UT C-Scan is used to determine the impact damage characteristics and CAI tests are carried out to evaluate quantitatively the reduction of compressive strength by impact loading. The damage modes of the woven glass/phenolic laminates are evaluated. In the case of the accelerated-aged laminates, as aging time increases, initial failure energy and residual compressive strength decrease.

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Response surface methodology optimization of electrospinning process parameters to fabricate aligned polyvinyl butyral nanofibers for interlaminar toughening of phenolic-based composite laminates

Journal of Industrial Textiles ◽

10.1177/1528083718798635 ◽

2018 ◽

Vol 49 (7) ◽

pp. 858-874 ◽

Cited By ~ 3

Author(s):

Parvaneh Kheirkhah Barzoki ◽

Masoud Latifi ◽

Amir Masoud Rezadoust

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Composite Laminates ◽

High Speed ◽

Polyvinyl Butyral ◽

Solution Concentration ◽

Electrospinning Process ◽

Optimum Conditions ◽

Nanofiber Diameter ◽

Mode Ii Fracture Toughness

In this study and for the first time, aligned nanofibers were produced from low molecular weight polyvinyl butyral. Using response surface methodology, the preparation condition of aligned nanofiber was optimized in terms of nanofiber diameter and its structural stability. Central composite design as a response surface methodology was employed and the effects of process variables and their influence on nanofiber diameter were investigated. Based on a statistical analysis, the use of a model, which was used to determine the nanofiber diameter, proved to be successful because of its low probability value (0.0073) and high correlation coefficient (0.9619). A high-speed cylinder collector was used to fabricate aligned polyvinyl butyral nanofibers. The optimum conditions of 17.5 kV voltage, 10 cm collector distance, 13% solution concentration, and 2100 r/min rotational speed were obtained from experiments. The least diameter of 158.6 nm along with a stable structure was determined for polyvinyl butyral nanofiber prepared under the optimum conditions. An aligned polyvinyl butyral nanoweb was applied on the mid-layer of glass-phenolic laminated composites as an interlaminar reinforcement. The fracture behavior of the laminates was determined by end-notched flexure tests. Excellent toughening property which was observed for the aligned polyvinyl butyral nanofibers caused the mode-II fracture toughness and its maximum force to increase by 25.2 and 40.8%, respectively.

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Improvement of Delamination Resistance in Glass/Phenolic Composite Laminates with Nano-interlayers

Eco-friendly and Smart Polymer Systems ◽

10.1007/978-3-030-45085-4_120 ◽

2020 ◽

pp. 493-496

Author(s):

Hossein Ipakchi ◽

Masoud Esfandeh ◽

Amir Masoud Rezadoust ◽

Mohammad Rezaei

Keyword(s):

Composite Laminates ◽

Delamination Resistance ◽

Phenolic Composite

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Pyrolytic carbon filaments and associated catalytic particles formed in steel tubes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100113196 ◽

1984 ◽

Vol 42 ◽

pp. 662-663

Author(s):

Y. L. Chen ◽

J. R. Bradley

Keyword(s):

Stainless Steel ◽

Carbon Steel ◽

Catalyst Particle ◽

Pyrolytic Carbon ◽

Plain Carbon Steel ◽

304 Stainless Steel ◽

Hydrocarbon Gases ◽

Steel Tubes ◽

Filamentous Carbon ◽

Carbon Filaments

Considerable effort has been directed toward an improved understanding of the production of the strong and stiff ∼ 1-20 μm diameter pyrolytic carbon fibers of the type reported by Koyama and, more recently, by Tibbetts. These macroscopic fibers are produced when pyrolytic carbon filaments (∼ 0.1 μm or less in diameter) are thickened by deposition of carbon during thermal decomposition of hydrocarbon gases. Each such precursor filament normally lengthens in association with an attached catalyst particle. The subject of filamentous carbon formation and much of the work on characterization of the catalyst particles have been reviewed thoroughly by Baker and Harris. However, identification of the catalyst particles remains a problem of continuing interest. The purpose of this work was to characterize the microstructure of the pyrolytic carbon filaments and the catalyst particles formed inside stainless steel and plain carbon steel tubes. For the present study, natural gas (∼; 97 % methane) was passed through type 304 stainless steel and SAE 1020 plain carbon steel tubes at 1240°K.

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Alterations of ultrastructure and elemental composition in cultured human epidermal keratinocytes after treatment with nitrofurazone and silver sulfadiazine

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100127803 ◽

1987 ◽

Vol 45 ◽

pp. 676-677

Author(s):

A. R. Crooker ◽

M. C. Myers ◽

T. L. Beard ◽

E. S. Graham

Keyword(s):

Electron Microscopy ◽

Elemental Composition ◽

Pyrolytic Carbon ◽

Human Keratinocytes ◽

Silver Sulfadiazine ◽

Epidermal Keratinocytes ◽

Human Epidermal Keratinocytes ◽

Culture Systems ◽

Cytotoxicity Endpoints

Cell culture systems have become increasingly popular as a means of screening toxic agents and studying toxic mechanisms of drugs and other chemicals at the cellular and subcellular levels. These in vitro tests can be conducted rapidly in a broad range of relevant mammalian culture systems; a variety of biological and biochemical cytotoxicity endpoints can be examined. The following study utilized human keratinocytes to evaluate the relative cytotoxicities of nitrofurazone (NF) and silver sulfadiazine (SS), the active ingredients of FURACIN(R) Topical Cream and SILVADENE(R) Cream, respectively. These compounds are anti-infectives used in the treatment of burn patients. Cell ultrastructure and elemental composition were utilized as cytotoxicity endpoints.Normal Human Epidermal Keratinocytes (HK) were prepared from the EpiPackTM culture system (Clonetics Corporation, Boulder, CO). For scanning electron microscopy (SEM) and transmission electron microscopy (TEM), cells were seeded on sterile 35 mm Falcon plastic dishes; for elemental microanalysis, cells were plated on polished pyrolytic carbon discs (E. Fullam, Latham, NY) placed in the culture dishes.

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