Polymer characterization (II

Pure and Applied Chemistry

To bolster the series of Brief Guides released by International Union of Pure and Applied Chemistry (IUPAC), here we introduce the first Brief Guide to Polymer Characterization. This article provides a concise overview of characterization methods for teachers, students, non-specialists, and newcomers to polymer science as well as being a useful manual for researchers and technicians. Unlike pure low molar mass chemical substances, polymers are not composed of identical molecules. The macromolecules which comprise a single polymer sample vary from one another, primarily in terms of size and shape, but often also in the arrangement or positioning of atoms within macromolecules (e.g., chain branching, isomerism, etc.). Polymer properties are often drastically different from those of other substances and their characterization relies on specialist equipment and/or common equipment used in a specialized way (e.g., particular sample preparation or data analysis). This Brief Guide focuses ...

2015

Polymers vary in terms of the monomer/s used; the number, distribution and type of linkage of monomers per molecule; and the side chains and end groups attached. Given this diversity, traditional single-technique approaches to characterization often give limited and inadequate information about a given polymer. Multi-technique but polymer-specific approach was found to be an appropriate alternative. This strategy was applied in characterizing polymers of a wide range of properties from simple polyethylene gylcol, to polycationic chitosan and aminopropyl based oligosiloxanes, and to polydiverse polyfluorinated polyethoxylates. Mass Spectrometry (MS) was used to characterize the different polymers. Different modes of sample introduction, ionization, mass analysis and detection were surveyed. The nature of the monomer units, the size and the polydispersity of polymers are the important factors that affect the detection and quantification of the polymer moieties using MS. MS gave inform...

rapra, 2002

Knowledge of the properties of materials is essential for several purposes: design, specification, quality control, failure analysis and for understanding the structure and behaviour of new materials. Specific test procedures evolve for each class of materials. These procedures are generally those found best suited to the generic characteristics of the material class and their use helps to provide the most meaningful results and to allow comparison of data from different sources. Plastics are no exception.

In the case of plastics these needs are particularly great because of the rapid change within the industry. The plastics in use today are very often not precisely the same as those available 10 years ago, even if the polymer is basically the same, and there are continuing refinements in processing. Also, plastics are being used in more and more new applications, and frequently more critical applications, than before. Thus, in many circumstances there is not much experience upon which to rely and this makes it very difficult to promote the use of plastics in, for instance, structural applications where a guaranteed 50-year performance may be wanted.

Annals of the University of Oradea: Fascicle of Textiles, Leatherwork, 2019

The study of natural and synthetic polymeric materials from modern and contemporary textile artworks can give scientists some difficulties in identification of the fibers or other components. Sometimes, time or environmental conditions can damage quite enough textile articles and because of that more and more techniques have been developed in order to assess the need to a better analysis of the samples. In addition to the lack of analytical equipment that can sometimes appear, a big problem is also the interpretation of the results. The main advantage of modern and contemporary textiles is that these products are easier to analyze because the time and environmental conditions at which they were exposed to do not have yet a major impact on them. In this paper are presented several types of analyzes and equipment that have non-destructive or micro-destructive properties. Some of these techniques have been used for decades, while others have been developed recently. Besides Scanning El...

Infrared Spectroscopy - Materials Science, Engineering and Technology, 2012