This article provides practical information and data on property development in engineering plastics. It discusses the effects of composition on submolecular and higher-order structure and the influence of plasticizers, additives, and blowing agents. It examines stress-strain curves corresponding to soft-and-weak, soft-and-tough, hard-and-brittle, and hard-and-tough plastics and temperature-modulus plots representative of polymers with different degrees of crystallinity, cross-linking, and polarity. It explains how viscosity varies with shear rate in polymer melts and how processes align with various regions of the viscosity curve. It discusses the concept of shear sensitivity, the nature of viscoelastic properties, and the electrical, chemical, and optical properties of different plastics. It also reviews plastic processing operations, including extrusion, injection molding, and thermoforming, and addresses related considerations such as melt viscosity and melt strength, crystallization, orientation, die swell, melt fracture, shrinkage, molded-in stress, and polymer degradation.

Infrared (IR) spectra have been produced by transmission, that is, transmitting light through the sample, measuring the light intensity at the detector, and comparing it to the intensity obtained with no sample in the beam, all as a function of the infrared wavelength. This article discusses the sampling techniques and applications of IR spectra as well as the molecular structure information it can provide. The discussion begins with a description of the general principle of IR spectroscopy. This is followed by a section on commercial IR instruments. Sampling techniques and accessories necessary in obtaining the infrared spectrum of a material are then discussed. The article presents various techniques and methods involved in IR qualitative analysis and quantitative analysis. It ends with a few examples of the applications of IR spectroscopy.

Mechanical properties are often the most important properties in the design and selection of engineering plastics. Temperature, molecular structure, crystallinity, viscoelasticity, and effects of environment, fillers and reinforcements are considered as the basic factors affecting the mechanical properties of engineering plastics. The testing methods for determining mechanical properties, including stress-strain test, modulus-directed tensile test, strength test, strength-directed tensile test, impact test, and dynamic mechanical test are discussed.

This article outlines the fundamentals of polymer science and emphasizes the aspects that are necessary and useful to applications of engineering plastics. The basic structure of polymers influences the properties of both polymers and the plastics made from them. An understanding of this basic structure permits the engineers to understand which polymers may be acceptable for a certain application, and which may not. There are various possible classification schemes for polymers. Typical classification categories include polymerization process, chemical elements that make up the monomer, or crystalline versus noncrystalline structure. The article describes the various aspects of chemical structure that are important to an understanding of polymer properties and, thus, affect eventual end uses. It discusses different types of names assigned to polymers. The article details the aspects of polymer structure and examines the properties of polymers and the way they are altered by structure.

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.