Adhesive component samples

Figure 7. Raman spectra of commercial adhesive component samples, (top to bottom) (a) Commercial urea (b) a commercial 40% formaldehyde solution (c) polythiane, synthesized by reaction of sodium sulfide arid formaldehyde (5) (d) the solid residue on a test sample bonded with formaldehyde-elemental sulfur in a 1 1 mixture (e) pure elemental sulfur ...

Acetylacetone (AcAc) infrared spectra were calculated with Hyper-Chem software. Calculations were carried out by the use of semi-empirical methods PM3 and ZINDO/1 and ah initio method with 6-3IG basis set [16]. Results of calculation have been compared with instrumental measurement performed IR-Fourier spectrometer FSM-1201. Liquid adhesive components were preliminary stirred in ratio 1 1 and 1 2 for the purpose of interaction investigation. Stirring was carried out with magnetic mixer. Silver powder was preliminary crumbled up in agate mortar. Then acetylacetone was added. Obtained mixture was taken for sample after silver powder precipitation. 

A simple joint test sample is subjected to temperature and humidity cycles before transverse tensile loading at a constant loading rate of (10 1) kN/min up to failure (Fig. 3). The objective is to evaluate the effect on bond strength of the damage to wood hbres caused by the action of acids from the adhesive during the climatic cycle. Thus, it must be achieved only if either the adhesive mixture or one of the adhesive components when apphed separately, show an acid pH value lower than 4.0. 

Polyvinyl alcohol is synthesized by the hydrolysis of polyvinyl acetate in a continuous process. Several grades are commercially available that differ with respect to the degree of polymerization and hydrolysis. Fully hydrolyzed samples are used primarily as warp sizes and partially hydrolyzed samples are used as adhesive components and polymerization aids [1]. 

ANSWER Epoxy adhesives, which comprise both the adhesive component and the hardener, are usually mixed with a static mixer. It is possible to use and monitor automatic flow controllers on both components of the adhesive. However, the most common way to determine the correct mix ratio is to periodically take a sample of the mixed adhesive and measure its properties, including density, cure speed, bond strength, etc. 

F-BDAF Tg for various blend compositions, see Fig. 14. The microphase-separated morphology further manifests itself in the self-adhesion behavior of polyimide films derived from such mixtures. For mixture containing at least 25 wt% of the flexible component, peel tests of polyimide bilayer samples prepared by solution casting, bulk failure of the test specimens was observed. Since the flexible component contained fluorine, the samples could be examined by X-ray photoelectron spectroscopy to determine the surface composition. At only 10% loading, the flexible component comprised 100% of the top 75 A of the sample. The surface segregation of the flexible component is believed to be responsible for the adhesion improvements. 

Similar to previous structure identification methods described for metabolites, impurities, and degradants, the knowledge of the physiological or chemical process, in this case the adhesive synthesis process, helped in the rapid interpretation of the MS/MS spectra of the unknown components. No user input about the sample composition is needed for the data-dependent analysis scheme thus, these experiments are simple and rapid to perform. The result is a fairly routine approach to structural screening of unknown mixtures during the manufacturing stage. 

Figure 12 represents a cross section of a plated sample of ULTEM 1000 having a peel strength of 118 g/mm. Little physical surface change of the plastic has occurred as a result of the pretreatment steps. Figure 13 is a cross section of copper plated ULTEM 2312. While a mechanical component to adhesion is present, it is much less than that found in traditional swell and etch treatment (Figure 2). Physical alteration of the plastic is confined to the outermost 25ii. The bulk properties of the plastic (flexural strength, electrical resistivity) are unaffected by this new process (Table I).

A second index of biocompatibility was the quantitative analysis of cell growth inhibition, again on mouse fibroblast L929 cells, induced by the liquid components of the adhesive system and water extracts of two solid crosslinked materials. Table IV is a summary of the percent inhibition of cell growth (percent ICG). The mean protein values at 4 °C have been subtracted from the mean protein values (five test samples) at 37 °C for each treatment condition. The percent inhibition of cell growth (percent ICG) is shown for each treatment condition. The precision of the assay is approximately 10%. 

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