This article discusses the properties, chemical structures, and applications of different types of elastomers grouped based on their resistance to aging (oxidative degradation), solvents, and temperature. These include butadiene rubber, natural rubber, isoprene rubber, chloroprene rubber, styrene-butadiene rubber, aerylonitrile-butadiene (nitrile) rubber, isobutylene-isoprene (butyl) rubber, ethylene-propylene (-diene) rubber, and silicone rubber. The article also provides an outline of the concerns related to the processing stages of rubbers or elastomers, including mixing or compounding, shaping, and vulcanizing or crosslinking.

Natural and synthetic rubber linings are used extensively in many industries for their corrosion and/or abrasion resistance. These industries include transportation, chemical processing, water treatment, power, mineral processing, and mining. This article provides information on soft natural rubber, semihard natural rubber, hard natural rubber, neoprene or polychloroprene, chlorobutyl, three-ply linings, nitrile, and ethylene propylene with a diene monomer. Emphasis is placed on advantages, disadvantages, and common uses of each material discussed.

This article presents a summary of the chemical fundamentals, general techniques, limitations, and applications of chemical spot testing as well as a brief overview of innovations and specialized applications. A list of selected reagents, including abbreviated instructions for preparing the reagent solution(s), for performing the spot test, and for interpreting the results, is also included. The article discusses two specialized applications of qualitative analysis, namely illicit drug identification and spacecraft drinking water quality testing. It also contains tables listing common presumptive tests for detecting anions and cations in aqueous solution.

Elastomers belong to a group of materials known as polymers that acquire their properties and strength from their molecular weight, chain entanglements, and crystalline regions. This article focuses on the use of elastomers as seals and describes its performance capabilities from the point of a sealant. The important technical concepts that define the performance capabilities of the elastomeric part include polymer architecture (molecular building blocks), compounding (the ingredients within the polymer), and vulcanization of the elastomer shape. The article discusses the aggressiveness of the chemical environment, temperature, and minor constituents in the environment and in the material itself that affect the chemical resistance of the elastomer. It provides a discussion on performance evaluation methods, namely, immersion testing and application specific testing that are determined using ISO and ASTM standards. The article concludes with information on elastomer failure modes and failure analysis.

This article is a compilation of abbreviations, symbols, and tradenames for terms related to the properties, selection, processing, and applications of the most widely used nonmetallic engineering materials.

This article begins with an overview of the fundamentals of adhesive technology, including functions, limitations, adhesive joint types, and the key factors in the selection of adhesives, including application, type of joint, process limitation, mechanical requirement, and service conditions. It then focuses on the characteristics, types, and properties of the five groups of adhesives, such as structural, hot melt, pressure sensitive, water based, ultraviolet, and electron beam cured adhesives. The article also discusses the functions and applications of adhesive modifiers, including fillers, adhesion promoters, tackifiers, and tougheners. It gives a short note on functions of primers and primerless bonding. Applications of adhesives in automotive, aerospace, electronics, electrical, medical, sports, and construction sectors are also described. Finally, the article describes the steps in adhesive bonding, including storage and handling of adhesives, bonding preparation, adhesive application, tooling, and curing.

Wipe solvents are used to remove contaminants from a workpiece before it undergoes manufacturing operations that require clean surfaces, such as bonding, sealing, painting, welding, plating, specialized surface treatment procedures, and others. This article describes the evaluation parameters for wipe solvent cleaners, including methyl ethyl ketone, methyl isobutyl ketone, trichloroethene, tetrachloroethylene, acetone, toluene, dichloromethane, benzene, xylene, and other alternate wipe solvent cleaners. It contains a table that lists the compositions and properties of wipe solvent cleaners.

This article provides a brief discussion on the common types of overlayers that can be used on a metal surface to protect it from corrosion. These overlayers include phosphate, chromate, and chromate-free conversion coatings; hot dip galvanizing; cementitious linings; glass and porcelain enamels; electroplating; thermal spray coatings; and rubber linings.

This article is a collection of tables that present information on the physical properties of periodic table elements, and maximum service temperatures, dielectric constants and typical dielectric properties of selected nonmetallic materials.

This article focuses on the heat removal stages involved in quenching, and on the experimental setup used for measuring temperature and detecting sound signals with the help of illustrations and curves. The quenching process generates acoustic signals, which are the consequences of the phase transformation of steel and of the boiling process at the interface during the cooling process. The sound-pressure signal is captured by the hydrophone through sound-emission measurements that occur during steel quenching in different quenching media. The analysis of the results offers an interesting approach to evaluation and, more importantly, to monitoring, controlling, and optimizing the entire quenching process.

This article is a comprehensive collection of engineering tables providing information on the mechanical properties of and the techniques for processing and characterizing polymeric materials, such as thermosets, thermoset-matrix unidirectional advanced composites, and unreinforced and carbon-and glass-reinforced engineering thermoplastics. Values are also provided for chemical resistance ratings for selected plastics and metals, and hardness of selected elastomers.

Thermoforming is a manufacturing process in which thermoplastic sheets are heated, softened, clamped onto a mold, and made to conform to the shape of the mold or forming tool. It is ideally suited to large-volume runs of small items. This article focuses on major phases of thermoforming, namely, sheet transportation, heating, forming/cooling, and trimming, and different thermoforming techniques: basic female forming; basic male forming; matched-mold thermoforming; plug-assist thermoforming; pressure bubble plug-assist vacuum thermoforming; vacuum snapback thermoforming; air-slip thermoforming; and trapped-sheet, contact heat, and pressure thermoforming. It concludes with a discussion on machines and the economic concerns of thermoforming.

This article provides an overview of curing techniques, adhesive chemistries, surface preparation, adhesive selection, and medical applications for adhesives. The curing techniques are classified into moisture, irradiation, heat, and anaerobic. The article highlights the common types of curable adhesives used for medical device assembly, including acrylics, cyanoacrylates, epoxies, urethanes, and silicones. Other forms of adhesives, such as hot melts, bioadhesives, and pressure-sensitive adhesives, are also discussed. Adhesives are used for medical device assembly, hard-tissue attachment in the fields of orthopedics and dentistry, and soft-tissue attachment such as wound closure. The typical characteristics and applications of biocompatible medical device adhesives are listed in a table. The article concludes with a section on selection of materials for medical adhesives.

Thermal analysis provides a powerful tool for researchers and engineers in determining both unknown and reproducible behavioral properties of polymer molecules. This article covers the thermal analysis and thermal properties of engineering plastics with respect to chemical composition, chain configuration, conformation of the base polymers, processing of the base polymers with or without additives; and the response to chemical, physical, and mechanical stresses of base polymers as unfilled, shaped articles or as components of composite structures. It also describes thermal analysis techniques, including differential scanning calorimetry, thermogravimetric analysis, thermomechanical analysis, and rheological analysis. This article also summarizes the basic thermal properties used in the application of engineering plastics, such as thermal conductivity, temperature resistance, thermal expansion, specific heat, and the determination of glass transition temperatures. It concludes with a discussion of the thermal and related properties of nine thermostat resin systems divided into three groups by low, medium, and high service temperature capabilities.

This article is an informative primer on sealants and the role they play in engineered assemblies. It discusses the physical, thermal, chemical, and electrical properties of sealant materials and the various forms in which they are applied, including liquids, pastes, and extruded tapes. It also describes classifications and types, comparing and contrasting sealants made from oil-based caulks, asphalts, coal tar resins, latex acrylic sealants, polyvinyl acetate caulks, solvent acrylics, butyl sealants, polysulfides, polyurethanes, modified silicones, anaerobics, vinyl plastisols, and polypropylenes. In addition, the article provides practical design insight, addressing application requirements, seal configurations, and joint stresses. It concludes with a brief discussion on the use of sealants in aerospace, automotive, electrical, and construction applications.

This article describes high-performance liquid chromatography and ultra-high-performance liquid chromatography that are used to separate and quantify the chemical components in any sample that can be dissolved in a liquid. This includes pharmaceutical drugs, medicinal plant extracts, food constituents, flavors, fragrances, industrial chemicals, pesticides, and pollutants. Readers are introduced to the most commonly employed mode, reverse-phase chromatography, with examples and an exclusive focus on commercially available instruments and consumables. The discussion covers the various processes involved in liquid chromatography, including assessing a separation of sample components, adjusting the mobile phase, choosing the stationary phase, optimizing a separation, preparing real samples, and analyzing complex samples.

This article commences with a description of the applications of galvanized coatings and provides information on metallurgical characteristics, such as coating thickness and alloying elements. It examines the effect of galvanizing process on the mechanical properties of steels and briefly describes the cleaning procedures of iron and steel pieces, before galvanizing. The article discusses the different types of conventional batch galvanizing practices. Information on the galvanizing of silicon-killed steels is also presented. The article concludes with helpful information on batch galvanizing equipment and galvanizing post treatments.

Functional fusion-bonded epoxy (FBE) coatings are used as external pipe coatings, base layer for three-layer pipe-coating systems, internal pipe linings, and corrosion coatings for concrete reinforcing steel (rebar). This article provides information on the chemistries of FBE, and discusses the application procedures for internal and external FBE pipe coating. The procedures involve pipe inspection, surface preparation, heating, powder application, curing, cooling, coating inspection, and repairing. It describes the problems and solutions for FBE external pipe coatings, girth weld FBE application, FBE custom coatings, internal FBE pipe linings, and FBE rebar coatings.

This article provides a detailed discussion on the principal classes and curatives of epoxy resins used in the coatings industry. The principal classes are bisphenol A epoxy, bisphenol F epoxy, epoxy phenol novolac, cycloaliphatic epoxies, epoxy acrylate, brominated bisphenol-A-based epoxy, phosphorus-containing epoxy, fluorinated epoxies, epoxy esters, epoxy phosphate esters, and waterborne epoxy. The principal curatives are amines, amine adducts, cyanoethylated amines, ketimines, polyoxyalkylene amines, cycloaliphatic amines, aromatic amines, polyamides, amido amines, and dicyandiamides. Other curatives include polyester co-polymers, phenolic co-polymers, melamine and urea formaldehyde co-polymer resins, phosphate flame retardants, ultraviolet and electron beam curing of epoxy resins, Mannich bases, Mannich-based adducts, and anhydrides. The article concludes by discussing the concerns regarding the use of epoxy coatings.

In terms of their electrical properties, plastics can be divided into thermosetting and thermoplastic materials, some of which are conductive or semiconductive. This article provides detailed information on factors that affect the property of plastics. It discusses the major test methods used to determine the following dielectric properties of plastics: dielectric breakdown voltage, dielectric strength, dielectric constant, dissipation factor, arc tracking resistance, insulation resistance, volume, and surface resistivity or conductivity. The test specifications and conditions, recommended by several U.S. and foreign testing organizations for characterizing the electrical properties of plastic materials are listed. The article describes the influence of these properties on selection of plastics for insulation application. An outline of the electromagnetic shielding and testing methods of electromagnetic interference are also provided. Designations, electrical properties, and applications of elastomers are tabulated.