Reading (Odian Book): Chapter 8-1, 8-2.

Slides:



Advertisements
Similar presentations
Pharmaceutical ORGANIC CHEMISTRY
Advertisements

Chapter 9 INTRODUCTION TO STEREOCHEMISTRY. Isomers are compounds with the same molecular formula but not identical structures.
CHAPTER 14: POLYMER STRUCTURES
Chapter ISSUES TO ADDRESS... What are the general structural and chemical characteristics of polymer molecules? What are some of the common polymeric.
Polymer Synthesis CHEM 421 Reading (Odian Book): Chapter 1.
Hydrocarbon Molecules
Chapter 4 Structures of Polymers.
Polymer Synthesis CHEM 421 Reading (Odian Book): Chapter 1-4, 1-5, 1-6.
STEREOCHEMISTRY By Puan Azduwin Khasri 8 th November 2012 By Puan Azduwin Khasri 8 th November 2012.
Synthetic Polymers. Introduction A polymer is a large molecule composed of many smaller repeating units. First synthetic polymers:  Polyvinyl chloride.
14.1 Introduction Schematic & Perspective Representation of Polyethylene Molecule.
Polymer Synthesis CHEM 421 Chapter 3.9 (Odian). Polymer Synthesis CHEM 421 Free Radically Polymerized Monomers.
Polymer Synthesis CHEM 421 Free Radical Polymerizations.
Polymers: 1. Introduction 2. The variety of Polymeric Materials Dept. Phys., Tunghai Univ. C. T. Shih.
Polymer Synthesis CHEM 421 Polymer Parameters Chemical structure –Chemical composition and distribution –Sequence length and distribution Molecular weight.
Macromolecular Synthesis
8/7/20151 Physical Polymer B.Pourabbas Faculty of Polymer Eng. Sahand University of Tech.
STEREOCHEMISTRY OF POLYMERIZATION The polymer properties are strongly affected by the molecular microstructure and not only the R. U. from which it is.
Chapter 26 Synthetic Polymers Jo Blackburn Richland College, Dallas, TX Dallas County Community College District  2006,  Prentice Hall Organic Chemistry,
Polymer Synthesis CHEM 421 Polymer Parameters Chemical structure –Chemical composition and distribution –Sequence length and distribution Molecular weight.
Alkenes By C Hughes. At the end of this lesson you should know: That bonding in alkenes involves a double bond. That the arrangement C=C is planar Understand.
Dr. Wolf's CHM 201 & Molecules with Multiple Chirality Centers.
7.13 Chemical Reactions That Produce Diastereomers
Ionic Polymerization.
Most common elements on earth are Si & O SiO 2 (silica) crystalline structures include quartz, crystobalite, & tridymite The strong Si-O bond leads to.
Polymer Structure Polyolefins with side chains have stereocenters on every other carbon With so many stereocenters, the stereochemistry can be complex.
Chapter 3 Alkenes and Alkynes. Alkene: Alkene: A hydrocarbon that contains one or more carbon-carbon double bonds. Ethylene is the simplest alkene. Alkyne:
Polymerization Reactions Chemistry II. Types of Polymerization Reactions Addition polymerization – monomers are added together, with no other products.
1 Polymer chemistry Polymer chemistry 2 1.5Microcosmic Structure of polymer.
Truth comes out of error more easily than out of confusion
Chemistry. Stereochemistry – 1 Session Session Objectives 1.Structural isomerism: chain, positional, functional, ring-chain, isomerism, metamerism, tautomerism.
 CHEMICALLY IDENTICAL
CHAPTER 4: POLYMER STRUCTURES
solid polymers: ~ g/mol
Chapter 2. Chain Structure and Configuration. Polymer chains have three basic properties: 1.The molecular weight and molecular distribution. 2.The conformation.
1 What is Organic Chemistry? Vitalism Examples of organic molecules What’s the common thread that ties these molecules together? Organic chemistry is the.
Chapter 5 Stereochemistry: Chiral Molecules 1.
Structure of Polymer Polymer Structure terms configuration and conformation are used to describe the geometric structure of a polymer Configuration refers.
Odian Book Chapter 3-15, 5-3.
Chemistry of Carbon Building Blocks of Life Why study Carbon?  All of life is built on carbon  Cells  72% H 2 O  25% carbon compounds  Carbohydrates.
Soluble Metallocene Cataysts Polyethylene
Polymer Synthesis CHEM 421 Chemical Review 2000, Issue 4 “FRONTIERS IN METAL-CATALYZED POLYMERIZATION” Also Angew. Chem. Int. Ed. 1999, 38, 428 ± 447.
Organic Chemistry By Dr. Mehnaz Kamal Assistant Professor,
Polymers Large molecules synthesized by bringing together many smaller molecules called monomers.
Molecular weight is different for polymers than it is for small molecules.
Stereochemistry 240 Chem Chapter 5 1. Isomerism Isomers are different compounds that have the same molecular formula.
Organic Molecules Carbon = building block of life Carbon – 4 outer electrons (8 needed) – Up to 4 bonds with other atoms Monomer: Small carbon molecules.
KANKESHWARIDEVIJI INSTITUE OF TECHNOLOGY, JAMNAGAR STEREOCHEMISTRY  Swati Agravat ( )  Shrushti Panchal ( )  Kaustubh Shah ( )
Tacticity.
Ionic Polymerization.
Ciencias de la tierra II
Chemistry 22.3.
Synthetic Polymers.
CHAPTER 4: Structures of Polymers
Carbon About half the dry weight of cells
By: Mdm Rohazita Bahari ERT 102 Organic Chemistry
Stereoisomerism.
Chapter 14: Polymer Structures
Atoms & Elements Molecules Compounds
CHAPTER 14: Structures of Polymers
CARBON CARBON EVERYWHERE!!
General Approaches to Polymer Synthesis
Fats, Carbs, and Proteins
23.29 Convert the following model into a condensed structure, and draw the structures of two isomeric compounds.
Unsaturated Hydrocarbons Alkynes and dienes
Lipids.
Lipids.
Analysis of i-PP made by Ziegler Natta Catalyst
Lipids.
Ch. 22 Hydrocarbons.
Presentation transcript:

Reading (Odian Book): Chapter 8-1, 8-2

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 Geometric isomers Stereo-isomers Conformational isomers

Geometric Isomers 1,3-butadiene cis-1,4-polybutadiene Tg = - 90 °C Tm = N/A (amorphous) trans-1,4-polybutadiene Tg = - 63 °C Tm = 100 °C 1,2-atactic-polybutadiene Tg = 0 °C

“Cis” vs. “Trans” Fats… Animal fats and vegetable oils Hardening H2 Vegetable oils polyunsaturated (several double bonds) Solid fats saturated (no double bonds) Hardening Convert liquid oils to solid fats…hydrogenation H2 Fat Pt

Chain Isomerism Regio-isomers Geometric isomers Stereo-isomers Conformational isomers

Stereoisomers “tacticity” Planar zig-zag conformation Asymmetric carbons “tacticity” Greek: “to put in order” Planar zig-zag conformation Relative configurations Isotactic

Stereoisomers Isotactic Syndiotactic Atactic

Model Systems meso- and racemic 2,4-disubstituted pentane

Model Systems meso- and racemic 2,4-disubstituted pentane

“Dyad” Analysis of Polymer Chains Meso dyad (m) a b Rac dyad (r) a a

“Dyad” Analysis of Polymer Chains Isotactic (mm) Syndiotactic (rr) Atactic or heterotactic (rm)

Why does stereochemistry matter? Atactic polystyrene Tg = 105 °C Tm = N/A Syndiotactic polystyrene Tg = 105 °C Tm = 270 °C

Why does stereochemistry matter?

Why does stereochemistry matter? Isotactic Syndiotactic Atactic Tm (°C) 165 135 N/A Density (g/mL) 0.92 – 0.94 0.89 – 0.91 0.85 Solubility (Hydrocarbons at Room Temp) none medium high Strength low

Stereochemistry and Synthesis 60 MHz 1H NMR spectrum of poly(methyl methacrylate) made using different initiators (A) Free Radical (B) Anionic

“Dyad” Analysis of Polymer Chains Meso dyad (m) Free radical Anionic a b Rac dyad (r) a Methylene centered around 2.2 ppm a Free radical polymer: predominantly syndiotactic Anionic polymer: predominantly isotactic

“Dyad” Analysis of Polymer Chains Methylene Perspective b a Need two monomer units to “look” or to “use” methylene protons for characterizing stereochemistry… m Methyl Perspective Need three monomer units to “look” or to “use” α-methyl group for characterizing stereochemistry… rr

Chain Isomerism Regio-isomers Stereo-isomers Geometric isomers Conformational isomers

Feedback: Privacy Policy Feedback
Do Not Sell My Personal Information
About project: SlidePlayer Terms of Service

© 2025 SlidePlayer.com. Inc. All rights reserved.