Peel strength measurements

After peeling of Al-polymer systems with adhesion-promoting plasma copolymer layers, the peeled surfaces were inspected again with XPS to determine the locus of failure, i.e., whether the peel front propagated along the interface (interfacial failure) or within the material (cohesive failure). 

Production of Polymer Surfaces Containing Functional Croups 

By means of OH- and COOH-containing plasma polymer layers the quahfica-tion of these layers as models of single-type functionalized adhesion promoters with variable concentrations of functional groups should be proved. The plasma-initiated copolymerization of acrylic acid with ethylene or 1,3-butadiene is shown in terms of measured COOH concentration as a function of the composition of the comonomer mixture in Fig. 18.3. Depending on the co-monomer reactivity, a more linear correlation (butadiene), or a parabolic behavior (ethylene), between precursor composition and COOH groups produced was observed. For each type and concentration of functional group, its concentration was determined by chemical derivatization followed by XPS analysis as described in Section 18.2.5. 

As shown in Fig. 18.4, similar tendencies were found for the aUyl alcohol copolymerization with ethylene, butadiene, or styrene. Here, the curves are observed to progress from a parabolic (ethylene) to a nearly linear correlation (butadiene) and to an anti-parabolic behavior (styrene) between measured OH group concentrations and the stoichiometry of the precursor mixture. 

By considering these curves it was possible to adjust to a defined concentration of functional groups in the deposited layer. Allylamine copolymer and pure 

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B533 peel strength measurement of plated plastics... 

Based on the above arguments, with peel strength measurements for the three SUV/Minivan tires. We will also include the elongation to break data for the Large Car-C tire even though the difference in wedge rubber modulus between the held and oven sets makes the comparison between these data sets somewhat questionable. 

Peel Strength Measurements of Al-Plasma Modified PP Systems... 

Peel strength measurement is always performed on pressure sensitive adhesives (PSAs) where it is the most important test. 

We will turn to an analysis of the peel strength measurement for an explanation. 

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