Reading (Odian Book): Chapter 1
Reading (Odian Book): Chapter 1. Polymer Parameters. Chemical structure Chemical composition and distribution Sequence length and distribution Molecular weight and distribution Chain isomerism Morphology Topology Additives Cost. Chemical Composition. Chemical Composition.
Reading (Odian Book): Chapter 1
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Reading (Odian Book): Chapter 1
Polymer Parameters • Chemical structure • Chemical composition and distribution • Sequence length and distribution • Molecular weight and distribution • Chain isomerism • Morphology • Topology • Additives • Cost
Chemical Composition • Infinite chain model notation • How best to characterize? • Why does sequencing matter? • Synthetic approaches? • Compositional distribution? • Branching? (refer to as topology…)
Polymer Parameters • Chemical structure • Chemical composition and distribution • Sequence length and distribution • Molecular weight and distribution • Chain isomerism • Morphology • Topology • Additives • Cost
Molecular Weight Property “X” Molecular Weight “X” = tensile strength density Tg etc
Molecular Weight Σni Mi Σwi Mi Mn = Mw = Σni Σwi
Molecular Weight Σni Mi Σwi Mi Mn = Mw = Σni Σwi • Populations • Memphis, TN 700,000 • Montrose, CO 10,000 • Effingham, IL 12,000 • Freeman, SD 1,500 • What is the Average Population? • 723,500 ÷ 4 = 180,875 • Of these four cities, the average citypopulation is 180,875 • Let’s think about the people… • What size city does the average person among these populations live in? • The average person does not live in a town of a population of 180,875… • Most of the people live in a town with a lot more than 180,000 people… • Need a weighted average
Molecular Weight Σni Mi Σwi Mi Mn = Mw = Σni Σwi • Populations • Memphis, TN 700,000 • Montrose, CO 10,000 • Effingham, IL 12,000 • Freeman, SD 1,500 • Weighted average • 700,000 ÷ 723,500 = 0.9675 • Take fraction and multiply that by the population of Memphis 0.9675 x 700,000 = 677,263 • Do the same for the others • 700,000 x 700,000 / 723,500 = 677,263 • 10,000 x 10,000 / 723,500 = 138 • 12,000 x 12,000 / 723,500 = 199 • 1,500 x 1,500 / 723,500 = 3 677,603 • The average person lives in a city of about 677,600 • More realistic than saying the average person lives in a city of 180,000!
Molecular Weight Σni Mi Σwi Mi Mn = Mw = Σni Σwi • What is the significance of the spread? • Polydispersity index (PDI) • PDI of polypeptides and DNA • How does magnitude of MW relate to synthesis? • How do you control PDI?
Gel Permeation Chromatography • What is principle behind GPC? • Direct or indirect method? • Why so useful? • Drawback? Detector Response Elution Volume (mL)
Polymer Parameters • Chemical structure • Chemical composition and distribution • Sequence length and distribution • Molecular weight and distribution • Chain isomerism • Topology • Morphology • Additives • Cost
Chemical Composition Distribution (CCD) • Interplay between CCD and MWD… • How to measure? • Ramifications? • Catalysis? • Phase separation? • Optical properties? • Degradation rates? • Toxicity? • Sequence length distribution
Polymer Parameters • Chemical structure • Chemical composition and distribution • Sequence length and distribution • Molecular weight and distribution • Chain isomerism • Morphology • Topology • Additives • Cost
Chain Isomerism • Regio-isomers • Stereo-isomers • Geometric isomers • Conformational isomers
Regio-isomers defect