Laminate film measurements

In this example a polymer laminate film (for packaging) was examined, which was composed of nine layers (see Table 2), by both FTIR imaging and Raman line scan. For the IR measurements thin sections (5 pm) were cut. The central ethylene/vinyl acetate (EVA) copolymer layer is very soft, and holes can be seen in the visible image (Figure 12). 

Instead of the simultaneously extmded polymer film, a pre-extmded or laminated film can be laminated on the substrate (e.g., paper or paper board). In this case, the extruder can be used to extrude the polymer providing adhesion (e.g., Ecoflex ) in a thin layer between the polymer coating film or laminate and the substrate. Another option is to apply a dispersion or heat in the laminator (Fig. 10, 4) to obtain adhesion. After thickness measurement and second subsequent corona treatment, substrate and polymer coating are wound on a winder (Fig. 10, 6) in order to obtain rolls for transport to subsequent processes (e.g., printing, cutting, cup forming, box making). 

Figure 25 shows the temperature dependence of relaxation time for the relaxation processes in the internal and interfacial regions of the ultrathin PS1.46M film sandwiched between the SiO layers. Since it was hard to distinguish the temperature-Ta relations between the vacuum deposited and laminated films, each data point was averaged over six independent measurements including both vacuum deposited and laminated films. The average thickness was about 40 nm. For comparison, the dashed curve in Fig. 25 denotes the bulk data obtained by the Vogel-Fulcher equation [72, 73] ... 

PA-FTIR depth profiling results are consistent with the known layer stmcture of a packaging laminate film and an adhesive label [477]. Doublelayered PET/PET, PP/PET and PET/PP laminates were studied by PA-FTIR [478]. PA-FTIR and DSC identified a skin layer and a core in injection moulded PET plates [479]. Plastic-coated paper was analysed by both PA-FTIR and DRIFTS allowing for shallow- and deep-sampling, respectively [453]. PA-FTIR is also a suitable tool for the analysis of polymer films used as a barrier coating on beverage and food containers at variance to specular reflectance measurements surface flatness is not critical. 

Figure 8.5. Coefficient of ffiction of LLDPE film (measured after 1 hour) with and without 500 ppm erucamide (em) and 10(X) ppm talc. [Data from Maltby, A., Polym., Laminations Coat Conf., San Francisco, Aug. 30-Sept 3, 1998,1241-50,1998.1...

In the example shown in Figure 13.18, the ATR spectra of layers of a laminate film cut obliquely by using a knife with an edge of synthetic diamond are shown. As an FT-IR spectrometer with a microscopic ATR apparatus was used, each of the measured spectra corresponds to an individual component without overlapping of the spectra by other layers. The individual layers were readily identified as a nylon, a polyester, probably PET, and a polypropylene. 

Packaging (qv) represents the largest market area for film and sheeting materials (15). It is a complex market with so many categories that it is difficult to get an accurate measure of end usage for specific materials (16). The stmcture of the marketplace which uses both monolayers of film, as well as converted composite stmctures and laminates, adds to the complexity. The ultimate user or packager may purchase raw film direcdy from a manufacturer, or use the same film laminated to one or more other films or substrates through a converter. The converter may buy film or extmde his own supply. Resin sales to film producers do not always correlate with their film sales, because of scrap and yield losses. 

In situ frequency dependent electromagnetic-impedence measurements provide a sensitive, convenient, automated technique to monitor the changes in macroscopic cure processing properties and the advancement of the reaction in situ in the fabrication tool. This chapter discusses the instrumentation, theory, and several applications of the techniques, including isothermal cure, complex time—temperature cure, resin film infusion, thick laminates, and smart, automated control of the cure process. 

Pike, L., Measurement of Oxygen Transmission Rates of Film and Thin Sheeting Under Humid Conditions, TAPPI Proceedings, Polymers Laminations and Coatings Conference (1986). 

For 1980 tests In Maryland, an effort was made to release a greater amount of the lure during the peak flight period of the insect by reducing the size of the flakes. The laminate (again 3-mll vinyl film) was chopped Into 2.4 x 2.4 mm squares (5.7 mm ). The two, as measured from the lure contents of recovered flakes, had only dropped to 53 days. 

The final dispenser evaluation with COMB pheromone again compared dispensers made of 3-mil acrylic film with those of 16-mil polymeric PVC the 13 x 13 mm laminate dispensers each contained 1 mg of racemic pheromone. Also included in this test were rubber septa baited with 1 mg of compound. All of the dispensers were aged outdoors in California at temperatures ranging from 32-39°C in the daytime to 15-21°C overnight. Analyses of residual lure contents showed a tof just 2 days for the rubber septa and approximately 15 days for the 16-mil polymeric PVC laminate the 3-mil acrylic dispensers lost pheromone so slowly that tj/2 could not be measured, but it was much greater than 70 days. On the basis of these tests, laminate dispensers made of 16-mil polymeric PVC were selected for the COMB monitoring program and have been successfully used in 1980 and 1981. 

The metallic layers were examined either by conventional or cross-section TEM in a Jeol 200 Cx microscope. For the cross section preparation a sandwich of two laminates is made, glued face to face with an epoxy, cut in small pieces, mechanically polished, and then ion milled to a final TEM observation thickness. The plane section TEM sample are prepared by dissolving the PET in trifluoroacetic acid for 5 to 10 mn. The area observed, on plane section TEM, for the grain size calculation is close to 0.2 urn. For the adhesion measurements, test pieces consist of aluminum support (1 mm thick) double sided tape (Permacel P-94) PET (12pm) / evaporated aluminum/ ethylene acrylic acid (EAA) copolymer film. These laminates are prepared for the peel test by compression under 1.3 105 N.m2 at 120°C for 10 seconds. The peel test is performed by peeling the EAA copolymer sheet from the laminate in an INSTRON tensile tester at 180° peel angle and 5 cm min peel rate. 

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