Chapter 1
Introduction
Overview
The characterization of all aspects of a polymer is enough to predict its performance. Instrumental methods help to find significant changes in composition or manufacturing process. For the desired performance, a meaningful characterization, based on selection from all possible molecular and structural parameters, will ensure that the testing is done with an economically feasible amount. There are inherent complications with chemical methods due to insolubility of polymer in a majority of solvents. Introduction of instrumental methods will enable the characterization of various polymer properties through a series of interfaced instruments. However, the success of characterization requires in-depth knowledge of polymer. Instrumental methods require careful calibration to produce meaningful results.
1.1. Objective: Polymer Testing
The main role of polymer testing is as a controlling tool that supports the development of chemical engineering and technology for production of polymers and chemicals. Polymer testing procedures provide information about the polymer, its properties, and additives. Product life-cycle analysis is impossible without the testing of components and products. The development of the standards and specifications to be used in industry is strongly based on the evidence obtained by testing controlled by chemical methods. Polymer testing is the only way to identify the environmental friendliness of new methods, processes, and products (Lewis 1996).
1.2. Necessity of Instrumental Methods
Characterization of polymers is inherently a more difficult process compared with other processes such as separation, filtration, and fractionation (Billmeyer 1975). Polymer samples are always a more or less complicated mixture of polymer and additives in some sort of a matrix. In view of this complexity, polymer testing is used to monitor and control the polymer and additives as raw materials (Rodriguez 1996). For identification, a comparison with the known physicochemical parameters and the known spectra is still the basic approach. Data is obtained through automatic instrumentation and high-throughput technology forces where instrumental methods are the main tools for further development (Sheldon 1994). Polymer testing helps reveal the processing characteristics, and this could result in an approach to select the proper identification and characterization methods. Polymer testing involves innovations with the continued development of polymers. It helps to meet the requirements in processing and applications. It determines the applications with instrumental techniques that measure and control technology. Instrumental methods require small samples from the volume of samples. They are fast and the results are reliable.
Polymer testing should involve easy and safe use of instruments in the laboratory. It should be adopted with all specific limits related to characterization, measurement, and calibration. Pretesting and process optimization are controlled by the best overview of the process. Polymer testing should be functionally oriented, particularly emphasizing measurement integration within an ergonomic working environment.
Instrumental methods help in the following:
- Determination of the processing behavior
- Processability evaluation
- Development of formulation
- Compounding
- Determination of the influences of additives
Polymer testing involves tests through all stages of processing of the complexity of polymers and their blends which are to be subjected to continuous development in terms of technology of measurement. Polymer testing is required for a more accurate determination of processing characteristics such as viscosity, homogeneity, and additive dispersion (Deanin 1978; Gearhart and Ball 1965; Stepek and Daoust 1983).
1.3. Specialization
The advantages of instrumental methods are as follows:
- The amount of polymer or additive sample required is extremely small. A few milligrams suffice, in many cases, to complete the quantitative analysis.
- A minimum amount of preparation of the sample for analysis is required. Simultaneous identification of the polymer and determination of their additive concentration is also possible.
- The testing sensitivity is great in terms of identifying the concentrations that may be contained even to a minimum level present in polymer matrices or blends.
- The precision and accuracy of analysis for polymer and additives occurring in concentrations of 0.001 to 0.0001 are valuable, for in many instances the instrumental methods provide the practicable means of determination.
- The rapidity of the method, where applicable, in general, saves a considerable portion of the time and cost required for chemical analysis.
Instrumental methods provide the following:
- Detailed structural analysis of polymer products
- Quality assurance/quality control (QA/QC) support in polymer production
- Defect analysis
- Identification of small differences between the chemical structures of polymers
- Analysis of additives in polymers
- Qualitative identification of polymer additives
Instrumental methods of polymer testing play an important role in identifying correct and concrete polymer properties (Wampler 1995; Wang and Smith 1996). They help to control the initial parameters of polymer, either in synthesis or in determining the properties of end products. Hence, it is necessary to understand the polymer matrix and the basics of the instrument that is necessary in order to understand the polymer properties. Many instrumental methods require the concepts of qualitative and quantitative performance as a driving force.
References
Billmeyer, Jr., F.W. 1975. “Introductory Remarks to Polymer Characterization Chapters.” In Characterization of Materials in Research: Ceramics and Polymers, eds. J.J. Burke and V. Weiss. Syracuse, NY: Syracuse University Press.
Deanin, R.D. 1978. “Chapter 4.” In Additives for Plastics, ed. R.B. Seymour. Vol. 1. New York, NY: Academic Press, pp. 404–408.
Gearhart, W.M., and F.M. Ball. 1965. “Plasticizers for Cellulosics.” In Plasticizers Technology, ed. P.F. Bruins. Vol. 1. New York, NY: Reinhold, p. 186.
Lewis, F.L. 1986. Optimal Estimation. New York, NY: Wiley.
Rodriguez, F. 1996. Principles of Polymer Systems. Philadelphia, PA: Taylor & Francis, p. 2.
Sheldon, R.A. 1994. “Consider the Environmental Quotient.” Chemtech 3, p. 38.
Stepek, J., and H. Daoust. 1983. “Plasticizers.” In Additives for Plastics, eds. J. Stepek and H. Daoust. New York, NY: Springer-Verlag, pp. 23–27.
Wampler, T.P. 1995. “Analytical Pyrolysis: An Overview.” In Analytical Pyrolysis Handbook, ed. T.P. Wampler. New York, NY: Marcel Dekker, pp. 1–3.
Wang, F.C.-Y., and P.B. Smith. 1996. “Quantitative Analysis and Structure Determination of Styrene/Methyl Methacrylate Copolymers by Pyrolysis Gas Chromatography.” Analytical Chemistry 68, pp. 3033–37.
Chapter 2
Importance of Polymer Testing
Overview
The characterization of polymers and chemical additives in polymer formulations is a challenging analytical problem. The additives together constitute the polymer matrix itself. Chemical methods provide little info...