Biomedical composites fibers

Of these, the reinforcement system in a cmnposite material strongly determines the properties achievable in a composite. It is thus convenioit and common to classify composites according to the characteristics of the reinforcement. These can include the shape, size, orientation, composition, distribution, and manner of incorporation of the reinforcement. For the purposes of a discussion of biomedical composites, this results in two broad groups, namely, fiber-reinforced and particle-reinforced composites. Figure 12.2 shows further divisions within these groups. 

C., and Zhu, L. (2009) Electrospun shikonin-loaded PCL/PTMC composite fiber mats with potential biomedical applications. Int. J. Pharm., 382, 215-221. 

Historically, EM has played important role in elucidating the structure and properties of various processing forms of classical polymer blends, composites fibers and biomedical objects. The microscopic analysis of certain special types of blend are examined in the following subsections. 

Silkworm silk, the silk from the cocoon of B. mori contains at least two major fibroin proteins, light and heavy chains, 25 and 325 kDa, respectively. These core fibers are encased in a sericin coat, a family of gluelike proteins that holds two fibroin fibers together to form the composite fibers of the cocoon case to protect the growing worm. Silkworm cocoon silk production, known as sericulture, produces high yields as the larvae can be maintained in high densities. The core sequence repeats in the fibroin heavy chain from B. mori include alanine-glycine repeats with serine or tyrosine [334]. It has been widely used as biomedical sutures and in textile production. 

Needless to mention, many types of the usual synthetic polymer composites are in use for decades now as matrices for several kinds of biomedical composite materials. Before the authors elaborate the progress made in the last decade with the conventional composites, for example, fiber-reinforced implants, they would... 

Kazanci, M. Cohn, D. Marom, G. Ben-Bassat, H. Surface Oxidation of Polyethylene Fiber Reinforced Polyolefin Biomedical Composites and its Effect on Cell Attachment. J. Mater. Sci. Mater. Med. 2002,13 (5), 465 68. 

Polysulfone hollow fibers, composite, 76 17 Polysulfone membranes, 75 811 Polysulfones, 70 202-204 properties of, 70 204t Polysulfone ultrafiltration hollow-fiber membrane, 76 4 Polyfsulfonic acid)s, 23 717-725 biomedical applications of, 23 722-723 uses for, 23 717... 

Fiber-reinforced composites contain strong fibers embedded in a continuous phase. They form the basis of many of the advanced and space-age products. They are important because they offer strength without weight and good resistance to weathering. Typical fibers are fiberous glass, carbon-based, aromatic nylons, and polyolefins. Typical resins are polyimides, polyesters, epoxys, PF, and many synthetic polymers. Applications include biomedical, boating, aerospace and outer space, sports, automotive, and industry. 

Another example of composites in biomedical applications is graphite-fiber-reinforced bone cement. Self-curing poly(methyl methacrylate), PMMA, is used extensively as a bone cement in orthopedic surgery for fixation of endoprostheses... 

Carbon/carbon composites fabricated by multiple cycles of liquid impregnation and recarbonization are a typical example of modern petroleum derived carbons. In the 1975 ACS Symposium on Petroleum Derived Carbons (JL), papers were presented on carbon/carbon composite materials formed by pyrolytic infiltration processes (2 ) or by liquid impregnation with petroleum pitch (3,4), on fabrication processes for high-modulus carbon fibers based on polyacrylonitrile (PAN) or pitch precursors ( 5 ), and on the use of carbon materials for thermostructural (6 ) as well as biomedical applications (1 ) ... 

Figure 8. Mechanical properties of various carbon-fiber-reinforced composites compared to bone and some biomedical alloys (20). HM and HT refer, respectively, to fibers of high modulus and high tensile strength.

Chitin is known to be biodegradable, biocompatible, and nontoxic. It is used in dmg delivery and bio medical applications. It also used in the purification of water especially for the absorption of toxic dyes. Chitin has limited solubility in solvents but chitosan is readily soluble in acidic aqueous solutions and has more tendency to be chemically modified. Chitosan can readily be spun into fibers, cast into films, or precipitated in a variety of micromorphologies from acidic solutions. Min and Kim have reported on the adsorption of acid dyes from wastewater using composites of PAN/chitosan [52]. Shin et al. has reported on copolymers composed of PVA and poly dimethyl siloxanes cross-linked with chitosan to prepare semi IPN hydrogels for application as biomedical materials... 

An up-date of the status of EB curing of carbon fiber composites was presented by A. Berejka. Developments proven successful for aerospace applications are now being seriously scrutinized for automotive use. The diversity of proven uses of radiation grafting for uses in batteries, porous film and non-woven filters, and release coated films and papers was also presented. Opportunities for use of grafting in biomedical applications, composites technology, and fuel cell membrane development were also discussed. 

Massachusetts Institute of Technology and his Ph.D. in chemical engineering at Princeton University. While at Princeton, his research was directed by Arthur V. Tobolsky in the area of polymer physical chemistry. He is currently professor of chemical engineering at the University of Wisconsin where, since 1967, he has been active in polymer research. He has published more than 80 papers on topics covering polyurethane block polymers, inomers, polymer yield mechanisms, composites, and fiber physics. His current research includes studies of protein and thrombus deposition on polymers used in biomedical applications. Professor Cooper is a Fellow of the American Physical Society and has served on the Board of Trustees of Argonne Universities Association. 

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