Interlayer thickness

Additional improvements have been incorporated since 1966 with the availabihty of thinner float glass. Glass thickness and interlayer thickness have been studied to optimize the product for occupant retention, occupant injury, and damage to the windshield from external sources (30,31). The thinner float glass windshields are more resistant to stone impacts than the early plate glass windshields. The majority of laminated windshields are made of two pieces of 2—2.5 mm aimealed glass and 0.76 mm of controlled adhesion interlayer. 

Many grades of interlayer are produced to meet specific length, width, adhesion, stiffness, surface roughness, color (93,94), and other requirements of the laminator and end use. Sheet can be suppHed with vinyl alcohol content from 15 to about 23 wt %, depending on the suppHer and appHcation. A common interlayer thickness for automobile windshields is 0.76 mm, but interlayer used for architectural or aircraft glaring appHcations, for example, may be much thinner or thicker. There are also special grades to bond rear-view mirrors to windshields (95,96) and to adhere the components of solar cells (97,98). Multilayer coextmded sheet, each component of which provides a separate property not possible in monolithic sheet, can also be made (99—101). 

Evidently, the critical pressure to cause failure decreases with a stiffer interphase modulus, E, or a reduced interlayer thickness, h, or both. This hypothesis has been tested on several simulation systems, which confirm that increased adhesion is possible with a negative transversal modulus gradient at the material interface. 

The interlayer thickness to fiber diameter ratio should be as large as other thermo-mechanical considerations would allow. 

This relation should also be valid for c, where c is the interlayer thick-... 

Fig. 18 Schematic representations and micrographs of damage case of the SiC / steel reference system and SiC/Ta/steel triple layers (x corresponds to the Ta interlayer thickness in microns).

Figure 2. Proposed orientation of the alkyne-rhodium triphenylphosphine complex between the silicate sheets of hectorite, prior to hydrogen transfer (top) the iidtti, obtained by subtracting the thickness of the silicate sheet ( 9.6 A) from the observed 001 X-ray reflection, is a measure of the interlayer thickness. The critical dimension of 2-decyne (bottom) is defined as the minimum distance which must be spanned by the molecule when the C C axis is perpendicular to the silicate...

Many process parameters are responsible for transcrystallinity." The most extensive transcrystallinity is observed under rapid pulling of fibers and high cooling rates. Other parameters include the viscosity of the polymer melt, the rate of shear, the fiber/matrix wettability, and the temperature gradient between matrix and fiberFigure 10.15 shows the effect of interlayer thickness on the fracture en-... 

Figure 10.15. Fracture energy vs. interlayer thickness in glass beads-reinforced epoxy. [Adapted, by permission, from Gerard J F, Chabert B, Macromol. Symp., 108, 1996, 137-46.]...

Type of interlayer Thickness of interlayer Deposition method Tr ( C) Ts CC) CH4 in H2 (vol. %) Gus How rate (seem) P Substrate Substrate (lorr) pretreatment material ... 

The bubble and the particle differ from each other not only in the potential of their surfaces but also in their behaviour, which may drastically change the arising interaction. The simplest situation is where the potential of the particle surface and the charge density of the bubble surface do not depend on the interlayer thickness. In the particular case where this change is zero, Frumkin Gorodetskaja (1938) and Langmuir (1938) showed that electrostatic repulsion results, which is exactly equal to the repulsion of two identical particles at the double thickness of the interlayer. 

The high compressibility along the [001] direction, largely related to the reduction in the interlayer thickness. This behavior is expected because of the weak bonding of the interlayer cation. The effect is more evident if the cation is potassium, and decreases if potassium is substituted by sodium (Fig. 2). 

SEM micrographs of impact-fractured surfaces of blends are shown in Fig. 19.12. The spherical particles are mainly PA6 and the black pits correspond to sites where PA6 particles were extracted from the PP matrix. Less and less PA6 particles are observed on the fractured surface as the PA6 content increases. The interlayer thickness is rather small when the POE content is as low as 5-10%, so that failure probably occurs at the PA6/POE interface in such a way that the PA6 surface is exposed. When the POE content increases, the interlayer becomes thicker and the failure occurs consequently at the PP/POE interface. This means that PA6 particles remain covered by POE after failure. 

It must be considered the work function reduction was closely relative to the thickness of the polymer interlayer. For example, the work function of ZnO increased from 2.47 eV (4 nm PEI) to 3.39 eV (16 nm PEI). This was because with the increasing polymer interlayer thickness, the random molecule dipoles coimtervailed with each other and thus weakened the interfacial dipole effect between ZnO and the interlayer. When polymer interlayer was used in the inverted structure, the device performance was obviously enhanced. Fig. 7.4D demonstrates the L-Vcurves of PLEDs. The tum-on voltage (voltage at luminance of 1 cdm and... 

Figure 9.17 Impact strength as a function of interlayer thickness. Source Reprinted with permission from Bell JP, Chang J, Rhee HW, Joseph R, Application of ductile polymeric coatings onto graphite fibres, Polym Composites, 8, 46-52, 1987. Copyright 1987, The Society of Plastic Engineers.

On the basis of all the material we have reviewed here, we can say that during the initial period of particle adhesion, i.e., in kinetic adhesion, the hydro-dynamic factor is operative in liquid media. As the particles approach the surface, the liquid is squeezed out and the interlayer thickness between the contiguous bodies approaches an equilibrium thickness corresponding to the transition between kinetic adhesion and static adhesion. In air-dusting with subsequent placement of the dust-covered specimen in a liquid, the contact zone becomes wetted, this zone is filled with liquid, and a liquid interlayer with equilibrium thickness is formed. 

Figs.l through 4 were taken from a joined MOR bar of Sic at different magnifications. The interlayer thickness is about 100 M ... 

Polished joined Sic MOR bar showing interlayer thickness of about 100 II. 

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