Polymers, Characterization molecular engineering

In this chapter we have explored the various methods by which polymer scientists characterize the molecular structure of polymers. Given the complex molecular distribution found in most polymers, the best that we can do in many cases is to measure some average value or distribution of values that represents the polymer. Armed with these values polymer scientists and engineers can design or select resins suitable for a myriad of practical applications. 

This volume provides an overview of polymer characterization test methods. The methods and instrumentation described represent modern analytical techniques useful to researchers, product development specialists, and quality control experts in polymer synthesis and manufacturing. Engineers, polymer scientists and technicians will find this volume useful in selecting approaches and techniques applicable to characterizing molecular, compositional, rheological, and thermodynamic properties of elastomers and plastics. 

Haider, M., Leung, V., Ferrari, F. et al. (2005) Molecular engineering of silk-elastin-like polymers for matrix-mediated gene delivery Biosynthesis and characterization. Molecular Pharmaceutics, 2, 139-150. 

Percec, V. and Lee, M. (1992) Molecular engineering of hquid crystal polymers by hving polymerization XXlll Synthesis and characterization of AB block copolymers based on o>-[(4-cyano-4 -biphenyl)-oxy]alkyl vinyl ether, IH, IH, 2H, 2//-perfluorodecyl vinyl ether, and 2-(4-biphenyloxy)ethyl vinyl ether with IH, IH, 2H, 2H-perfluorodecyl vinyl ether. J M S - Pure and Applied Chemistry, A29,723-740. 

These principles of crystal engineering and supramolecular synthesis have thus far been used to design, isolate, and characterize network structures from relatively small molecular components. In the context of coordination polymer networks, a recent review indicates how wide the range of chemical components and accessible network motifs has become.48b However, the scale of these structures is such that cavities and channels are on the order of 1 nm and, to date, each cavity is identical. Careful selection of appropriate substrates or components and ever more control over crystal packing will offer the potential for rational design of an even more extensive array of modular (i.e. binary, ternary, or even higher order) structures than those that are currently available. In particular, judicious choice of supermolecules... 

GPC is a form of size-exclusion chromatography (SEC) used by polymer chemists and plastics engineers for the characterization of synthetic or natural polymers. Separation is by effective molecular size or hydrodynamic volume using columns packed with materials of 5-10 pm particle size (e.g., cross-linked polystyrene gels) with well-defined pore distribution (see Table 7.8). 

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