Problem solving fiber studies

Characterization of fiber microstructure normally requires several microscopy techniques, as was shown in the simple example in the last section. An optical cross section of a fiber may have a dogbone shape (Fig. 5.2D), and yet this image does not reveal much about the internal fiber structure. On the other hand, a fracture surface of a fiber may reveal the presence of internal detail when viewed in the SEM (Fig. 5.11), and yet still not provide a complete picture of the structure. Clearly, complementary microscopy techniques and nonmicroscopy techniques must be applied to solving structural problems. Specific problem solving examples are described here which are representative of the wide range of studies conducted and documented in the many journals that publish polymer research. 

Fibers used in compo.sites pre.sent some special practical considerations for the surface scientist, and this chapter will focus upon such considerations. There will be no attempt to review the large btxly of work in this area (1-5], but the empha.sis will be on the problem-solving methods relevant to the study of composites. 

Surface analysis has an important role to play in the study of composites and fibers. Many surface analytical methods are available, but XPS is the most extensively used because surface chemical infonnation is essential. The two most important practical points are that samples be mounted and handled very carefully in the spectrometer and that the data be analyzed thoroughly. Complete problem solving cannot be achieved unless the surface analyst uses the full extent of information available (e.g., by careful curve re.soiution and by making use of valence band spectra). This chapter has given many examples of the type... 

As a new kind of carbon materials, carbon nanofilaments (tubes and fibers) have been studied in different fields [1]. But, until now far less work has been devoted to the catalytic application of carbon nanofilaments [2] and most researches in this field are focused on using them as catalyst supports. When most of the problems related to the synthesis of large amount of these nanostructures are solved or almost solved, a large field of research is expected to open to these materials [3]. In this paper, CNF is tested as a catalyst for oxidative dehydrogenation of propane (ODP), which is an attractive method to improve propene productivity [4]. The role of surface oxygen annplexes in catalyzing ODP is also addressed. 

How to solve this problem is difficult to state and many approaches can be taken. Alternative forms of transportation such as pipelines for liquids and sometimes solids, water movement, truck-rail (piggy-back), and truck-water (fishy-back) combinations, are all possibilities. Plant relocations to minimize shipping distances to major customers, or to allow direct across -the-fence movements, should be considered. The use of the newer, or the yet-to-be-developed containers, such things as bulk rubber bags for liquids, bulk handling of dry solids via air slides, etc., lined fiber drums for liquids, should all be carefully studied. The creation of bulk distribution points may in some instances be of value. 

An alternative approach to solving stability problems with ILMs is presented by Bhave and Sirkar (114). Aqueous solutions are immobilized in the pore structure of hydophoblc, polypropylene hollow fibers by a solvent exchange procedure. Gas permeation studies are reported at pressures up to 733 kPa with the high pressure feed both on the shell and lumen sides of the laboratory scale hollow fiber permeator. No deformation of the hollow fibers is observed. Immobilizing a 30 weight % KjCO, solution in the hollow fibers greatly improved the separation factor, a(C02/Na). from 35.78 with pure water to 150.9 by a facilitated transport mechanism. Performance comparisons with commercial COj separation membranes are made. 

Extensive research has been undertaken in blending different polymers to obtain new products having some of the desired properties of each component. Among protein- and polysaccharide-based green materials, those made from soy protein (Maruthi et al. 2014 Ghidelli et al. 2014 Behera et al. 2012) and starch (Katerinopoulou et al. 2014 Flores-Hemandez et al. 2014) have been extensively studied for and their physiochemical properties been analyzed. The literature review clearly shows that development of biodegradable biopolymer-based materials based on these materials can not only solve the white pollution problem but also ease the overdependence on petroleum resources. This chapter provides a brief overview of the preparation, properties, and application of cellulose fiber-reinforced soy protein-based and starch-based biocomposites. 

In Section 2.5, the application of adaptive fiber composites to influence the behavior of helicopter rotor blades is outlined. To simulate such a system, an adaptive beam, as considered in the two previous chapters, needs to be examined in the rotating environment. Besides the already complicated interactions due to arbitrary mechanical and electromechanical couplings, this requires consideration of additional couplings due to gyroscopic and second-order theory effects. Consequently, the general problem may only be solved with the aid of discretization, to be accomphshed here by means of the finite element method. Analytic solutions of manageable complexity, however, may be found for simplified problems and can be utilized for fundamental studies and to support the validation of the finite element solution. 

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