Introduction to physical Polymer Science

Values of Often Used Constants and Useful
Conversion Factors
1 Introduction to Polymer Science
1.1 From Little Molecules to Big Molecules / 2
1.2 Molecular Weight and Molecular
Weight Distributions / 6
1.2.1 Effect on Ultimate Tensile Streagth
1.2.2 Molecular Weight Averages / c
1.3 Major Polymer Transitions / 8
1.4 Polymer Synthesis and Structure / 9
1.4.1 Chain Polymerization / 9
1.4.1.1 Free Radical Polymerzation
1.4.1.2 Initiation / 10
1.4.1.3
Propugation / 10
1.4.1.4 Termination / 11
1.4.1.5 Structure and Nomen lature
11
1.4.2
Step Polymerization / 13
1.4.2.1 A Polyester Condensaion
Reaction / 13
1.4.2.2
Stepwise Nomenclatur: and
Stratures / 15
1.5 Cross-Linking. Plasticizers, and Fillers / 16
1.6 The Macromolecelar Hypothesis / 16
1.7 Historical Deveiopment of Industrial
2
Chain Structure and Configuration
2.1 Examples of Configurations and Conformations / 24
2.1.1 Head-to-Head and Head-to-Tail
Configurations / 24
2.1.2 Trans-Gauche Conformations / 24
2.2
Theory and Instruments / 25
2.2.1
Chemical Methods of Determining
Microstructure / 25
2.2.2
2.2.3
General Physical Methods / 26
Infrared and Raman Spectroscopic
Characterization / 28
2.2.4 Nuclear Magnetic Resonance Methods / 29
Stereochemistry of Repeating Units / 30
2.3.1 Chiral Centers / 30
2.3.2 Tacticity in Polymers / 30
2.3.3 Meso- and Racemic Placements / 34
2.3.4 Proton Spectra by NMR / 35
2.4
Repeating Unit Isomerism / 37
2.4.1 Optical Isomerism / 37
2.4.2 Geometric Isomerism / 37
2.4.3 Substitutional Isomerism / 38
2.4.4 Infrared and Raman Spectroscopic
Characterization / 38
2.5 Common Types of Copolymers / 40
2.5.1 Unspecified Copolymers / 41
2.5.2
2.5.3
Statistical Copolymers / 41
2.5.4
Random Copolymers / 42
Alternating Copolymers / 42
2.5.5 Periodic Copolymers / 42

Polymer science was born in the great industrial laboratories of the world of the need to make and understand new kinds of plastics, rubber, adhesives, fibers, and paints. Only much later did polymer science come to academic life. Perhaps because of its origins, polymer science tends to be more
interdisciplinary than most, combining chemistry, chemical engineering, ma-teriais, and other fields as well.
Chemically, polymers are long-chain molecules of very high molecular weight, often measured in the hundreds of thousands. For this reason, the term
"macromolecules" is frequently used when referring to polymeric materials. The trade literature sometimes refers to polymers as resins, an old term that goes back before the chemical structure of the long chains was understood.
The first polymers used were natural products, especially cotton, starch. proteins, and wool. Beginning early in the 20th century, synthetic polymers were made. The first polymers of importance, Bakelite and nylon, showed the tremendous possibilities of the new materials. However, the scientists of that day realized that they did not understand many of the relationships between the chemical structures and the physical properties that resulted. The research that ensued forms the basis for physical polymer science.
This book develops the subject of physical polymer science, describing the interrelationships among polymer structure, morphology, and physical and mechanical behavior. Key aspects include molecuiar weight and molecular weight distribution, and the organization of the atoms down the polymer chain. Many polymers crystallize, and the size, shape, and organization of the crystallites depend on how the polymer was crystallized. Such effects as annealing are very important, as they have a profound influence on the final state of molecular organization.

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