Fiber composites single polymer

Yavin, B., Gallis, H. E Scherf, J., Eitan, A. and Wagner, H. D., Continuous monitoring of the fragmentation phenomenon in single fiber composite materials, Polym. Composites, 12, 436 (1991). 

AN Netravali, W Sachse. Some remarks on acoustic emission measurements and the single-fiber-composite test. Polymer Composites 12 370-373, 1991. 

Sun X, Li H, Zhang X, Wang J, Wang D and Yan S (2006) Effect of fiber molecular weight on the interfacial morphology of iPP fiber/matrix single polymer composites. Macromolecules 39 1087-1092. 

Figure 12.41 Optical micrographs showing the morphologies of an iPP fiber/matrix single-polymer composite. The fiber introduction temperature was 173 °C. The crystallization temperature was 138 °C. Li et al. [132]. Reproduced with permission of American Chemical Society.

Anisotropic materials have different properties in different directions (1-7). 1-Aamples include fibers, wood, oriented amorphous polymers, injection-molded specimens, fiber-filled composites, single crystals, and crystalline polymers in which the crystalline phase is not randomly oriented. Thus anisotropic materials are really much more common than isotropic ones. But if the anisotropy is small, it is often neglected with possible serious consequences. Anisoiropic materials have far more than two independent clastic moduli— generally, a minimum of five or six. The exact number of independent moduli depends on the symmetry in the system (1-7). Anisotropic materials will also have different contractions in different directions and hence a set of Poisson s ratios rather than one. 

Asloun, El. M., Nardin, M. and Schultz, J. (1989). Stress transfer in single-fiber composites Effect of adhesion, elastic modulus of fiber and matrix and polymer chain mobility. J. Mater. Sei. 24, 1835-1844. 

Netravali, A.N., Hcnstenburg, R.B., Phoenix, S.L. and Schwartz, P. (1989a). Interfacial shear strength studies using the single filament composite test, part I Experiments on graphite fibers in epoxy. Polym. Composites 10, 226-241. 

Scherf, J. and Wagner, H.D, (1992). Interpretation of fiber fragmentation in carbon/epoxy single fiber composites Possible fiber pre-tension effects. Polym. Eng. Sci. 32, 298-304. 

Self-reinforced PP is an intriguing avenue for creating a more recyclable, single-polymer, reinforced material. Such a composite system is reinforced by oriented, drawn PP fibers within a PP matrix, or as part of a laminated system. However, current cost disadvantages have limited their use [7-42]. 

Ward and his coworkers investigated the interlayer adhesion in self-reinforced PP composites modified with different nano- and micron-sized particles [27-29]. They found that the introduction of a small amount of carbon nanofibers (CNFs) led to improved performance of polypropylene single-polymer composites obtained by hot compaction of oriented CNF/ PP tapes. The peel strength of a CNF/PP woven fabric composite was significantly increased. In addition, the authors pointed out that the drawn CNF/PP tapes showed substantial voiding around the fibers which were closed and sealed by the hot compaction process. As a result, the composite density increased to its initial value [27]. 

Keywords Interfacial shear strength Lignocellulosic fiber Microlxaid test Polymer composite Pullout test Single fiber fragmentation test... 

Considerable work has been done on the sisal fiber-reinforced epoxy composites. It is reported that the fractured cross sections of the sisal-epoxy composites, showed no epoxy resin in the fiber lumen. The total lumen area in the fiber cross-section was fotmd to be 15% and the total void content was about 17%. In sisal, total leaf mass contains only 2-4% sisal fibers other cells take care of the water distribution. Oksman et al. [9] studied the thermoplastic fiber composites and showed that lumen was filled with the polymer matrix. Fibers therefore have distribution channels between the single wood cells. It is possible that the absence of such channels in sisal, due to the different function of sisal fibers, is the reason for lack of polymer in the lumen. At several locations in the sisal fiber, a gap between the fiber and matrix can be observed. The gaps indicate weak fiber-matrix adhesion [9, 58, 59]. 

The micro- and nanofibrils isolated in a neat form after selective dissolution of the second blend component, even after preparation of fabrics or knitted articles from the blend yarn, can be used as a starting material for preparation of nanostructured single polymer composites. A PET nanofibrillar SPC prepared via hot compaction using one constituent shows a modulus competitive with that of the glass fiber/PE (40/60 by wt) composites. 

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