q 2006 by Taylor & Francis Group, LLC q 2006 by Taylor & Francis Group, LLC q 2006 by Taylor & Francis Group, LLC [...]... Comparative Corrosion Resistance of Thermoplastic and Thermoset Polymers 221 Reference 441 Chapter 5 Elastomers 5.1 Introduction 5.1.1 Importance of Compounding 5.1.2 Similarities of Elastomers and Thermoplastic Polymers 5.1.3 Differences between Elastomers and Thermoplasts 5.1.4 Causes of Failure 5.1.5 Selecting an Elastomer 5.1.6 Corrosion. .. long-term adhesion of the coating is affected by the properties of the polymer such as stiffness or rigidity, dimensional stability, and coefficient of expansion The physical properties of the paint film must accommodate to those of the polymer 1.5 Corrosion of Polymers Corrosion of metallic materials takes place via an electro-chemical reaction at a specific corrosion rate Consequently, the life of a metallic... & Francis Group, LLC Corrosion of Polymers and Elastomers 16 5 Plasticizers and other additives Most polymers are formulated with plasticizers and chemical additives These materials have a tendency to migrate to the surface and may even soften the coating and destroy adhesion The specific polymer should be checked to determine whether the coating will cause short- or long-term softening or adhesion... property and chemical resistance differences of polymers stem directly from the type and arrangement of atoms in the polymer chains In the periodic table, the basic elements of nature are placed into classes with similar properties, i.e., elements and compounds that exhibit similar behavior These classes are alkali metals, alkaline earth q 2006 by Taylor & Francis Group, LLC 18 Corrosion of Polymers and Elastomers. .. Group, LLC Corrosion of Polymers and Elastomers 12 produced from the same polymer will provide an indication of the relative permeation rates The denser the sheet, the lower the permeation rate The thickness of the liner is a factor affecting permeation For general corrosion resistance, thicknesses of 0.010–0.020 in are usually satisfactory, depending on the combination of lining material and the specific... cellulose were giant molecules of high molecular weight These are natural condensation polymers, and understanding their structure paved the way for the development of the synthetic condensation polymers such as polyesters, polyamides, polyimides, and polycarbonates The chronological order of the development of polymers is shown in Table 1.1 A relatively recent term, engineering polymers, has come into play... quantities of permeant vapors to escape, but also to prevent expansion of entrapped air from collapsing the liner Permeation is a function of two variables: one relating to diffusion between molecular chains and the other to the solubility of the permeant in the polymer The driving force of diffusion is the partial pressure of gases and the concentration gradient of liquids Solubility is a function of the... high-performance polymers and engineering plastics According to the ASM Handbook, engineering plastics are defined as “Synthetic polymers of a resin-based material that have loadbearing characteristics and high-performance properties which permit them to be used in the same manner as metals and ceramics.” Others have limited the term to thermoplastics only Many engineering polymers are reinforced and/ or alloy polymers. .. continuous phase, and the fiber reinforcement is the discontinuous phase The function of the resin is to bond the fibers together to provide shape and form and to transfer stresses in the structure from the resin to the fiber Only high-strength fibers with high modulus are used Because of the increased stiffness resulting from the fiber q 2006 by Taylor & Francis Group, LLC Corrosion of Polymers and Elastomers. .. temperature, and the chemical enduse environment 1.1 Additives Various properties of polymers may be improved by the use of additives In some instances, the use of additives to improve a specific property may have an adverse effect on certain other properties Corrosion resistance is a property most often affected by the use of additives In many cases a polymer’s corrosion resistance is reduced as a result of . editor of the Corrosion Engineering Handbook and the Corrosion and Corrosion Protection Handbook, Second Edition; and the author of Corrosion Resistance Tables, Fifth Edition; Encyclopedia of Corrosion Technology,. Materials; Corrosion Resistant Linings and Coatings; Atmospheric Degradation and Corrosion Control; What Every Engineer Should Know About Corrosion; Corrosion Resistance of Elastomers; Corrosion Resistant. Piping Systems; Mechanical and Corrosion Resistant Properties of Plastics and Elastomers (all titles Marcel Dekker, Inc.), and Paint and Coatings, Applications and Corrosion Resistance (Taylor