Microdroplet test

The microbond test is also mentioned as the microdroplet test [39] and believed to possess some of the characteristics of fiber pullout in composites [34]. The test consists of a microdroplet of still fluid polymeric resin deposited onto a fiber, as shown in the schematic diagram of Fig. 9.9 [53]. 

Parks et al. [39] applied the nucrobond (or microdroplet) test to measure the IFSS of NaOH-treated ramie and kenaf fibers with different lengths embedded into an epoxy microdroplet as in Fig. 9.9. These lignoceUulosic fibers/epoxy nucrodroplet specimens were fixed by a microdevice and tested to obtain the pullout force F and... 

Czigany T, Morlin B, Mezey Z. Interfacial adhesion in fully and partially biodegradable polymer composites examined with microdroplet test and acoustic emission. Compos Interfaces 2007 14 869-878. 

Raman spectroscopy was used in conjunction with the microdroplet test and the fragmentation test method to quantifiably calculate the average maximum interfacial shear strength between an aramid fiber and a Pebax 7033 matrix. 

The microdroplet test or variations of it have been used with good success for a variety of fibers using epoxy as the matrix [27]. When using epoxy or other matrix materials in which it is possible to control the viscosity, a concentric and uniform droplet can be applied to the single fiber. In this work, it was found that it was very difficult to maintain a consistent droplet cross-section area, which would have implications when comparing results from one specimen to another. Also, since the cross-sectional areas would differ, the amount of strain-... 

Key Words Interfacial Shear Strength, Raman spectroscopy, aramid fiber. Fragmentation test. Microdroplet test, thermoplastic composite... 

In order to determine a partition coefficient, water, n-octanol, and test compound are equilibrated with each other after which the concentration of the test compound in the two phases is determined. The experimental difficulties associated with the formation of microdroplets during the shake-flask experiment can to some degree be overcome in the slow-stirring experiment as water, octanol, and the test compound are equilibrated in a gently stirred reactor. The stirring creates a more or less laminar flow between the octanol and the water, and exchange between the phases is enhanced without microdroplets being formed. 

One complicating factor in the analysis of mitochondria from tissue cross sections is that mitochondria are found in two locations in muscle tissue (i) subsarcolemmal mitochondria are found directly beneath the sarcolemmal membrane and are easily extracted and (ii) interfibrillar mitochondria are located between the myofibrils and require exposure to a protease to be efficiently released. To release these latter mitochondria, a short treatment with trypsin was tested by depositing a microdroplet of trypsin on the fiber before sampling. Table 20.2 compares the analysis of mitochondria from muscle fiber that had undergone trypsin treatment with the analysis of mitochondria from... 

Microdroplet specimens were prepared in a similar fashion to Eichorn and Young [27], except that strands of molten Pebax 7033 were placed onto the surface of an aramid fiber [28]. For the fragmentation study, single fiber composite samples were prepared and subjected to increasing levels of strain on a Minimat tensile rig. The technique for the single fiber pull out test is described elsewhere [28]. 

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