Fiber-matrix separation

Londono-Hurtado, A., Hemandez-Ortiz, 1. P. and Osswald, T. A. (2007), Mechanism of fiber-matrix separation in ribbed compression molded parts . Polymer Composites, 28(4), 451-157. 

Mobius T, Eilbracht S, Rudolph N, Osswald TA. Analysis of fiber orientation and fiber matrix separation in a compression molding process with an equi-biaxial flow front. J Plast Technol 2013 9(2) 101-28. 

Fiber Jamming and Fiber Matrix Separation during processing of fiber reinforced composites. 

Fiber jamming is perhaps the least imderstood defect in molding of polymer composites. This paper presents a dimensional analysis developed to predict fiber distribution in ribbed sections. The model shows that parameters like mold closing speed and polymer viscosity can be optimized to decrease fiber matrix separation. 

Fiber jamming, fiber matrix separation, dimensional... 

Where the parameter r is a factor that accounts for the fraction of fibers that are bent at the entrance of the rib. Fiber-matrix-separation will occm for values of 0 1, since the force required to squeeze the resin out of its fiber bed is much lower than the force needed to bend the fibers into the rib. On the other hand, good fiber distribution of fibers throughout the rib can be expected for 0 1 since the resin and the fiber flow together into the rib. 

FIBER JAMMING AND FIBER MATRIX SEPARATION DURING PROCESSING OF FIBER... 

This research field will be developed further in the following section since it represents an efficient and powerful tool for the chemist, making compatible different aspects of the chemistry that initially were separated organic chemistry, inorganic and organometallic chemistry can now be unified with solid-state chemistry as well as macromolecular chemistry. Livage and Rouxel have introduced the word chimie douce by contrast to the usual method that required high-temperature processes [11, 12]. In addition, this chimie douce allows a control of the shape of the solid (film, fiber, matrix, monolith) that is important in the perspective of devices. 

The work of Valadez-Gonzalez et al. [37] was the only study reported so far to compare two methods, the SFP and the SFF, using a lignocellulosic fiber. In their work, the IFSS of henequen fibers embedded in polyethylene was separately evaluated by means of both SFP and SFF tests. The fibers were previously subjected to different surface chemical treatments aiming at improving the fiber/matrix adhesion. Table 9.3 shows the probable results obtained as a composition of Fig. 11 and Table 4 of Valadez-Gonzalez et al. [37] article. 

A new technique, which is applicable for sampling in air and liquids or in the headspace above a liquid or a solid sample, is solid-phase micro-extraction (SPME). The mechanism of SPME, which has been developed by Pawliszyn et al. 1225], [226], is based on the partition equilibrium of the analytes between the sample or the head-space above the sample, respectively, and a fused silica fiber coated with a suitable stationary phase. The amount of analyte extracted by the fiber is proportional to the initial analyte concentration in the sample and depends on the type of fiber. After sampling, the fiber can be thermally desorbed directly into the injector of a gas chromatograph. SPME combines sampling, analyte enrichment, matrix separation, and sample introduction within one step [226]. Since its development, this innovative technique has found widespread use in environmental analysis. It has, for example, been applied in the determination of volatile organic compounds [227], 228]. phenols [229],... 

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