The Mechanical Properties of Chitosan Membranes

Chitosan and zeolite were composited by incorporation of zeolite into chitosan membranes in varying amounts from 50 to 100wt% of chitosan and glutaraldehyde was used to crosslinking.The zeolite loading in the chitosan membranes was varied in the range of 10%-30%, showing high mechanical properties even in the high zeolite loading. Potential adsorption targeted to waste elimination of heavy metal cations was carried out by using the chitosanzeolite composite membranes. In the permeation experiment, the selectivity of the composite membranes to especially chromium (Cr) was observed in the order of Cr>As>Cd >Hg>Pb>Cu. It was noted that the composite membrane having zeolite loading with 30 wt.% showed the highest performance adsorption selectivity. These results reveal that the composite membranes had a potential avility to purify wastewater by removing heavy metal ions.

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Studies on the mechanical properties of silk fibroin membranes. (Part 3). The mechanical properties of fibroin-chitosan membranes.

Sen i Gakkaishi ◽

10.2115/fiber.47.7_334 ◽

1991 ◽

Vol 47 (7) ◽

pp. 334-338 ◽

Cited By ~ 14

Author(s):

Chuan Xin Liang ◽

Kiyoshi Hirabayashi

Keyword(s):

Mechanical Properties ◽

Silk Fibroin ◽

Chitosan Membranes

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Durable pectin/chitosan membranes with self-assembling, water resistance and enhanced mechanical properties

Carbohydrate Polymers ◽

10.1016/j.carbpol.2018.01.112 ◽

2018 ◽

Vol 188 ◽

pp. 136-142 ◽

Cited By ~ 26

Author(s):

Jéssica G. Martins ◽

Ariel C. de Oliveira ◽

Patrícia S. Garcia ◽

Matt J. Kipper ◽

Alessandro F. Martins

Keyword(s):

Mechanical Properties ◽

Water Resistance ◽

Self Assembling ◽

Chitosan Membranes

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Bioactivity and Viscoelastic Characterization in Physiological Simulated Conditions of Chitosan/Bioglass® Composite Membranes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.636-637.26 ◽

2010 ◽

Vol 636-637 ◽

pp. 26-30 ◽

Cited By ~ 3

Author(s):

Sofia G. Caridade ◽

Esther G. Merino ◽

Gisela M. Luz ◽

N.M. Alves ◽

João F. Mano

Keyword(s):

Mechanical Properties ◽

Storage Modulus ◽

Tissue Regeneration ◽

Viscoelastic Properties ◽

Mechanical Performance ◽

Composite Membranes ◽

Mechanical Analysis ◽

Chitosan Membranes ◽

Tan Δ

A number of combinations of biodegradable polymers and bioactive ceramics have been used for orthopaedic applications including in hard tissue regeneration. Ideally, composites aimed to be used in orthopaedic applications should combine adequate mechanical properties and bioactivity. Chitosan (CTS) has been widely used for biomedical applications, namely in tissue regeneration or drug delivery. In this sense, membranes of chitosan and chitosan with Bioglass® (BG) were prepared by solvent casting and characterised using Scanning Electron Microscopy. In vitro bioactivity tests were performed in the composite membranes, namely by monitoring their capability to induce the precipitation of apatite upon immersion in simulated body fluid (SBF). The results showed that the addition of BG promoted the deposition of an apatite-like layer. The deposition of apatite could influence the mechanical performance of the material. Therefore, in order to follow this biomineralization, the viscoelastic properties of these composite membranes (immersed in SBF) were evaluated. The change in the storage modulus (E’) and the loss factor (Tan δ) were measured as a function of immersion time using non-conventional dynamic mechanical analysis (DMA) tests, in which the samples were kept in wet conditions and at 37°C during the measurements. The mechanical properties of the chitosan membranes were improved by the addition of BG particles. An increase on the storage modulus was observed by the composite membranes while for the pure chitosan membranes the storage modulus was stable up to 7 days. Clear changes were detected in the composite membranes that contrasted with pure chitosan (CTS) membranes that exhibit stable viscoelastic properties up to 7 days. In addition, this work showed that sample characterization in the hydrated state can be useful to predict the mechanical performance of composites under meaningful physiological conditions.

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Phase Transformations in Ti-7w/oMo-3w/oMe Alloy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052584 ◽

1974 ◽

Vol 32 ◽

pp. 514-515

Author(s):

S. Fujishiro

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Transmission Electron Microscopy ◽

Tensile Strength ◽

Mechanical Processing ◽

Ray Method ◽

X Ray ◽

Transmission Electron ◽

Water Quench ◽

Alpha Beta

The mechanical properties of three titanium alloys (Ti-7Mo-3Al, Ti-7Mo- 3Cu and Ti-7Mo-3Ta) were evaluated as function of: 1) Solutionizing in the beta field and aging, 2) Thermal Mechanical Processing in the beta field and aging, 3) Solutionizing in the alpha + beta field and aging. The samples were isothermally aged in the temperature range 300° to 700*C for 4 to 24 hours, followed by a water quench. Transmission electron microscopy and X-ray method were used to identify the phase formed. All three alloys solutionized at 1050°C (beta field) transformed to martensitic alpha (alpha prime) upon being water quenched. Despite this heavily strained alpha prime, which is characterized by microtwins the tensile strength of the as-quenched alloys is relatively low and the elongation is as high as 30%.

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Effects of cooling rate on the mechanical properties of dual phase treated vanadium steels

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074896 ◽

1983 ◽

Vol 41 ◽

pp. 220-221

Author(s):

L.J. Chen ◽

H.C. Cheng ◽

J.R. Gong ◽

J.G. Yang

Keyword(s):

Mechanical Properties ◽

Cooling Rate ◽

Automobile Industry ◽

High Strength ◽

Weight Percent ◽

Low Alloy Steels ◽

Dual Phase ◽

Resource Requirement ◽

Alloy Steels ◽

Potential Weight

For fuel savings as well as energy and resource requirement, high strength low alloy steels (HSLA) are of particular interest to automobile industry because of the potential weight reduction which can be achieved by using thinner section of these steels to carry the same load and thus to improve the fuel mileage. Dual phase treatment has been utilized to obtain superior strength and ductility combinations compared to the HSLA of identical composition. Recently, cooling rate following heat treatment was found to be important to the tensile properties of the dual phase steels. In this paper, we report the results of the investigation of cooling rate on the microstructures and mechanical properties of several vanadium HSLA steels.The steels with composition (in weight percent) listed below were supplied by China Steel Corporation: 1. low V steel (0.11C, 0.65Si, 1.63Mn, 0.015P, 0.008S, 0.084Aℓ, 0.004V), 2. 0.059V steel (0.13C, 0.62S1, 1.59Mn, 0.012P, 0.008S, 0.065Aℓ, 0.059V), 3. 0.10V steel (0.11C, 0.58Si, 1.58Mn, 0.017P, 0.008S, 0.068Aℓ, 0.10V).

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Lattice Imaging of Grain Boundaries in Ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100078171 ◽

1977 ◽

Vol 35 ◽

pp. 114-115

Author(s):

D. R. Clarke ◽

G. Thomas

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Silicon Nitride ◽

Grain Boundaries ◽

High Temperature Strength ◽

Current Interest ◽

Lattice Imaging ◽

Special Significance ◽

Structural Applications ◽

Refractory Ceramics

Grain boundaries have long held a special significance to ceramicists. In part, this has been because it has been impossible until now to actually observe the boundaries themselves. Just as important, however, is the fact that the grain boundaries and their environs have a determing influence on both the mechanisms by which powder compaction occurs during fabrication, and on the overall mechanical properties of the material. One area where the grain boundary plays a particularly important role is in the high temperature strength of hot-pressed ceramics. This is a subject of current interest as extensive efforts are being made to develop ceramics, such as silicon nitride alloys, for high temperature structural applications. In this presentation we describe how the techniques of lattice fringe imaging have made it possible to study the grain boundaries in a number of refractory ceramics, and illustrate some of the findings.

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Electron Microscopic Observation of the Longitudinal Organization of Poly (p-Phenylene Terephthalamide) Fibers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055734 ◽

1982 ◽

Vol 40 ◽

pp. 680-681

Author(s):

Li Li-Sheng ◽

L.F. Allard ◽

W.C. Bigelow

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Scanning Electron Microscopy ◽

Microscopic Observation ◽

Electron Microscopic Observation ◽

Electron Microscopic ◽

Aromatic Polyamides ◽

Radial Arrangement ◽

Scanning Electron ◽

Better Than

The aromatic polyamides form a class of fibers having mechanical properties which are much better than those of aliphatic polyamides. Currently, the accepted morphology of these fibers as proposed by M.G. Dobb, et al. is a radial arrangement of pleated sheets, with the plane of the pleats parallel to the axis of the fiber. We have recently obtained evidence which supports a different morphology of this type of fiber, using ultramicrotomy and ion-thinning techniques to prepare specimens for transmission and scanning electron microscopy.

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