Peek formula

Taking into account that ln(l/y) 6-8, ignition of the positive corona requires slightly higher electric fields (Lowke D Alessandro, 2003). The igniting electric field for the coaxial electrodes in air can be calculated using the empirical Peek formula ... 

Nylon, polyacetal, polycarbonates, poly(2,6-dimethyl)phenylene oxide (PPO), polyimides, polyphenylene sulfide (PPS), polyphenylene sulfones, polyaryl sulfones, polyalkylene phthalates, and polyarylether ketones (PEEK) are stiff high-melting polymers which are classified as engineering plastics. The formulas for the repeating units of some of these engineering plastics are shown in Figure 1.15. 

Peek s ac formula is approximately correct for dc fields, (Cobine, 1958). 

Polymer Specimens. The materials used in this work were polyimide (PI),polyamide-imide (PAl), polyether-ether-ketone (PEEK), polyphenylene sulfide (PPS) and polyether sulphone (PES). The chemical formulas and physical properties of the specimen polymers are summarized in Table I. The specimen polymers, except PPS, were unfilled while the PPS specimen was filled with glass fiber of Uo wt. %. PAI and PES are amorphous polymer with considerably high glass temperature. The polymers, except PI, can flow at hi temperatures and allow the use of injection molding. 

Polyetheretherketone (PEEK) is an engineering thermoplast having the following formula ... 

If you have studied Chapter 6 and you get stuck while answering a question because you cannot write a formula, we urge you to review the appropriate section of Chapter 6 before continuing. Avoid the temptation to just peek at the list of formulas. Developing skill in chemical nomenclature is part of your learning process in this course, and in many cases, you truly learn the material from Chapter 6 as you apply it here in Chapter 7 and throughout your study of chemistry. 

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