Fibrous blend

In a letter to the Annals of Philosophy, dated Cambridge, February 18, 1820, Edward Daniel Clarke wrote as follows Some varieties of radiated blende from Przibram in Bohemia are described by Stromeyer as containing two or three per cent of cadmium. At a sale. .. in London, I procured specimens of the particular mineral thus alluded to, which were sold under the name of splendent fibrous blende from Przibram, pronounced Pritzbram. I found afterwards that they had been brought to England by Mr. J. Sowerby of Lisle-street, a dealer in minerals.. . . Upon my return to Cambridge, I endeavoured to obtain cadmium from this ore, and succeeded. . . (133). Clarke also found this element in die zinc silicate from Derbyshire, England, and his results were soon confirmed by W. H. Wollaston and J. G. Children. In 1822 Clarke published a paper on the presence of cadmium in commercial sheet zinc (134). 

Cheng Mei-Ling, Chen Po-Ya, Lan Chin-Hung, Sun Yi-Ming, Structure, mechanical properties and degradation behaviors of the electrospun fibrous blends of PHBHHx/ PDLLA. Polym. 2011, doi 10.1016/j.polymer.2011.01.039 in press. 

Cheng, Mei-Ling, Chen, Po-Ya., Lan Chin-Hung, Sun Yi-Ming. (2011). Structure, Mechanical Properties and Degradation Behaviors of the Electrospun Fibrous Blends of PHBHHx/PDLLA. Polymer, 52, 6587-6594. 

Application of scanning electron microscopy (SEM) allows the observation of appearance of fibres and their changes during the enzymatic degradation (see Fig. 4.20). As a result of the enzymatic degradation process for the polyester-cellulose fibrous blends, the degree of saccharification of cellulose fraction was achieved at a level up to 99 wt.%. 

Fibrous blends can serve as internal reinforcements or perhaps electrical conductors, depending on the polymer characteristics comprising them. Where very thin fibers can be formed (< 1 [tm), for example, opportunities exist for enhancing crystallinity and tensile properties of the resulting blends especially when extrusions containing them, which themselves can be fibers, are drawn to promote polymer chain orientation [33]. 

Figure 19.8 Low and high magnification views of a fibrous blend formed in an extruded monofilament consisting of PP and PS. Internal fibers encapsulate fibers so the filament has a novel hierarchical structure that may be associated with physical property enhancements.

This is also known as Bulk Moulding Compound (BMC). It is blended through a mix of unsaturated polyester resin, crosslinking monomer, catalyst, mineral fillers and short-length fibrous reinforcement materials such as chopped glass fibre, usually in lengths of 6-25 mm. They are all mixed in different proportions to obtain the required electromechanical properties. The mix is processed and cured for a specific time, under a prescribed pressure and temperature, to obtain the DMC. 

High-shock grades cannot be proeessed on mills or other intensive mixers without destroying the essential fibrous structure of the filler. In these cases a wet process is used in which the resin is dissolved in a suitable solvent, such as industrial methylated spirits, and blended with the filler and other ingredients in a dough mixer. The resulting wet mix is then laid out on trays and dried in an oven. 

Faser-asbest, m. fibrous asbestos, -asche, /. fiber ash. -bildung, /. fiber formation, fibra-tion. -blende, /. fibrous sphalerite. Faserchen, n. little fiber, fibril, filament. Faserfarbung, /. coloration of the fiber, faserfdrmig, a. fibrous, filiform. 

Scbalen-bau, m. shell structure, -blende, /. fibrous sphalerite, -entwickelimg, /. (Pho tog.) tray (or dish) development, schalenfdrmig, a. bowl-shaped, dish-shaped, cup-shaped shell-like. 

Materials with totally new property combinations may be achieved by blending two or more polymers together. Through blending of thermotropic main-chain LCPs with engineering thermoplastics, the highly ordered fibrous structure and good properties of LCPs can be transferred to the more flexible matrix polymer. LCPs are blended with thermoplastics mainly in order to reinforce the matrix polymer or to improve its dimensional stability, but LCP addition may modify several... 

Fig. 10. Scanning electron micrograph of a fracture surface parallel to the direction of extrusion of an extrudate of a 45 55 PS-HDPE blend with a viscosity ratio p 1. Fibrous PS is shown at different stages of breakup the diameter of the largest fiber is about 1 pm (Meijer el til., 1988).

Techniques commonly used to produce fibrous webs include the wet laid, dry laid carded, and meltblown processes. The wet laid or paper making process is the predominant method for several reasons. The wet laid process, configured properly, allows for the blending of cellulosic and polymeric components. Also, the ability to use short cut length and fine denier fiber provides for consistent blending, uniform formation, and controlled pore structure. 

Figure 5 presents the results of tensile tests for the HPC/OSL blends prepared by solvent-casting and extrusion. All of the fabrication methods result in a tremendous increase in modulus up to a lignin content of ca. 15 wt.%. This can be attributed to the Tg elevation of the amorphous HPC/OSL phase leading to increasingly glassy response. Of particular interest is the tensile strength of these materials. As is shown, there is essentially no improvement in this parameter for the solvent cast blends, but a tremendous increase is observed for the injection molded blend. Qualitatively, this behavior is best modeled by the presence of oriented chains, or mesophase superstructure, dispersed in an amorphous matrix comprised of the compatible HPC/OSL component. The presence of this fibrous structure in the injection molded samples is confirmed by SEM analysis of the freeze-fracture surface (Figure 6). This structure is not present in the solvent cast blends, although evidence of globular domains remain in both of these blends appearing somewhat more coalesced in the pyridine cast material.

Blend cotton fibers (80 parts) -b fibrous cotton-PMMA (53% add-on) copolymer (20 parts). 

The growth of these materials is reflected in the number of polymers which are being glass reinforced. These include polypropylene, polystyrene, styrene acrylonitrile, nylon, polyethylene, acrylonitrile-butadiene-styrene, modified polyphenylene oxide, polycarbonate, acetal, polysulfone, polyurethane, poly (vinyl chloride), and polyester. In addition, the reinforced thermoplastics available now include long-fiber compounds, short-fiber compounds, super concentrates for economy, a combination of long and short fibers, and blends of polymer and fibrous glass. 

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