1. Course Plan  Week 1 Introduction: Polymers? Historical background, Classification Structure and Properties: Chemical structure and Composition  Week 2 Structure and Properties: Molecular weights and Measurements  Week 3 Structure and Properties: Morphology and Transition behavior, Viscoelasticity  Week 4 Synthesis: Step growth polymerization  Week 5 Synthesis: Free radical chain growth polymerization  Week 6 Polymerization Process, Micro- Nano- polymer particulates  Week 7 Synthesis: Ionic chain growth polymerization  Week 8 Midterm test  Week 9 Copolymers, Polymer blends  Week 10 Elastomers, Polymers for textile  Week 11 Functional Polymers: Engineering plastics, Thermally stable polymers  Week 12 Functional Polymers: Biodegradable polymers, Biomedical polymers  Week 13 Functional polymers: Membranes, Fuel cell, Li-battery, Energy transducers  Week 14 Functional polymers: Conducting polymers Photosensitive polymers  Week 15 Functional polymers: Polymer-inorganic hybrids, Term paper/projects  Week 16 Final test

2. Course Plan  References: Polymer Chemistry  Tae-wan Ahn  The Elements of Polymer science and Engineering  Alfred Rudin  Introduction to Polymer Science  R.J. Young and P.A. Lovell  Evaluation: Midterm35% Final Test 35% Assignments 20%  Participation 10%  Assignments: Problem sets 1, 2, 3, 4, 5  Term paper(individual) or Term project(group of 2-3)

3. Introduction CHAPTER 1 BASIC PRINCIPLES

4. 1. 1 Introduction and Historical Development  Polymer derives from Greek terms “Polymer” = “poly” + “mer”  Macromolecule is a term synonymous with polymer.  Molecular Weights of thousands to millions.  Many thousands of different molecules even in “pure” samples  Polymers are synthesized from simple molecules called monomers ("single part") by a process called polymerization.  Examples of Common Polymers

5. Historical Development  Natural Polymers have been mainstays of human technology since the dawn of time (e.g., leather, string/cloth, paper)  Term “Polymer” 1 st used by Berzelius in 1833  Nitrated cellulose (almost always incorrectly called nitrocellulose)  Styrene polymerization reported 1839 soon after styrene chemistry began but structure was not clear to authors  Poly(ethylene glycol) reported in 1860s with correct structure  Phenol-formaldehyde resin made on commercial scale in early 1900’s by Leo Baekeland as “Bakelite” (this is still a very large scale material)  WWII was a major spur to the polymer industry and supporting science  Artificial rubber to replace natural Malaysian rubber  Nylon to replace silk  Synthetic Fuels ⇒ monomeric staring materials  Invested infrastructure costs  Thermodynamic arguments by Hermann Staudinger (Nobel Prize in 1953) and Wallace Carothers  Karl Ziegler in Germany; Giulio Natta in Italy (Nobel Prize in 1953)  A quantitative basis for polymer behavior by Paul Flory (Nobel Prize in 1974)  http://chem.chem.rochester.edu/~chem421/famous.htm http://chem.chem.rochester.edu/~chem421/famous.htm

7. Match the structures to the following trade names:  Butvar ( TM Monsanto)  Dacron ( TM DuPont)  Lexan ( TM General Electric)  Nylon 6 ( TM DuPont)  Noryl ( TM General Electric)  Kapton ( TM DuPont)  Dowlex ( TM Dow)

8. Famous polymer Scientist  Nobel Prize Winners  H. Staudinger (1953) polymer chain formula.  G. Natta & K. Ziegler (1963) coordination polymerization and stereoregular polymers. Natta's biography Ziegler's biography Natta's biography Ziegler's biography  P. Flory (1974) Polymer thermodynamics, kinetics, molecular weight distribution, solution theory. Autobiographical sketch Autobiographical sketch  B. Merrifield (1984) Solid phase polypeptide synthesis. Prof. Merrifield's group web site His autobiography (Amazon.com) Prof. Merrifield's group web site His autobiography (Amazon.com)  P. DeGennes (1993) Polymer solid state theory and liquid crystals. Prof. Degennes web site Prof. Degennes web site  Alan Heeger, Alan MacDiarmid, and Shirakawa (2000) electrically conducting and semiconducting polymers  Alan Heeger Nobel Prize Lecture Alan Heeger Nobel Prize Lecture  Interview with Prof. Heeger regarding conducting polymers Interview with Prof. Heeger regarding conducting polymers  Alan MacDiarmid - Short biography Alan MacDiarmid - Short biography  One more scientist (Nobel Prize in 1921) whose contributions concerning Brownian motion, viscosity of solutions, and light scattering are essential to polymer science, even if he is best known for other, unrelated work.

9. 1. 2 Definitions

10. Definitions  Representation of polymer types  Network polymers are formed when linear or branched polymer chains are joined together by covalent bonds, a process called crosslinking.  Degree of Crosslinking directly correlated with: hardness, elasticity, solvent induced swelling, etc. degree of swelling indicates degree of solvent-polymer compatibility and the degree of crosslinking Can be via covalent bonds, ionic interactions, or Van der Waals interactions (more later)  First “designed” crosslinking process is Vulcanization of rubber (Polyisoprene) linear branched network dendrimer polycatenane polyrotaxane star polymer comb polymer semiladder (or stepladder) polymer ladder polymer

11. Definitions  Thermoset Polymers  Example phenol-formaldehyde resin (above)  Properties Insoluble Non-melting Flexibility ⇒ Extended Solids  Thermoset (e.g., Phenol-Formaldehyde) vs. Thermoplastic Polymer (e.g., PE)  Classification by Use  Plastics  Fibers  Rubbers (Elastomers)  Coatings  Adhesives

12. 1. 3 Polymerization Processes  Classification of Polymer Reactions at Stoichiometric and Mechanistic Scales  Reaction Stoichiometric Classification Addition vs. Condensation Polymerization (first proposed by Carothers) determined by loss of weight (or not) on polymerization  Mechanistic Classification Step-Growth (Step-Reaction) vs. Chain-Growth (Chain-Reaction) need intimate reaction details to be certain

13. 1.4 Step-reaction Polymerization  Two approaches to preparing linear step-reaction polymers:

14. Step-reaction Polymerization

15. 1. 5 Chain-reaction Polymerization  Chain-reaction polymerization involves two distinct kinetic steps, initiation and propagation. (termination, chain transfer)

16. Chain-reaction Polymerization

17. 1.6 Step-reaction Addition and Chain-reaction Condensation  Most step-reaction polymerizations are condensation processes and most chain-reaction polymerizations are addition processes.  A step-growth addition reaction  A chain-growth condensation reaction

18. Step-reaction Addition and Chain-reaction Condensation  In 1994 the International Union of Pure and Applied Chemistry (IUPAC) proposed four new polymerization classifications:  Polycondensation-the same as step-reaction polymerization with concurrent formation of low-molecular-weight byproducts.  Polyaddition-the same as step-reaction polymerization without formation of byproducts.  Chain polymerization-the same a s chain-reaction polymerization without formation of byproducts.  Condensative chain polymerization-the same as chain-reaction polymerization with the formation of low-molar-mass byproducts

19. 1. 7 Nomenclature  IUPAC has proposed perfectly logical rules:  IUPAC, Compendium of Macromolecular Nomenclature, Blackwell, Oxford, 1 99 1 ; Pure Appl. Chem., 65, 1561 ( 1993); ibid., 66, 873 ( 1994).  1.7.I Vinyl Polymers  Place the prefix “poly” before the name of the corresponding monomer.  The IUPAC recommends that names be derived from the structure of the base unit, or constitutional repeating unit (CRU), according to the following steps: The smallest structural unit (CRU) is identified. Substituent groups on the backbone are assigned the lowest possible numbers. The name is placed in parentheses (or brackets and parentheses, where necessary), and prefixed with poly.

20.  Diene monomers Use cis- and trans- to indicate geometric isomer 1,2- and 1,4- to indicate positions of free double bonds derived from olefin polymerization.  E.g., Source nameIUPAC name 1,2-addition1,2-Poly( 1,3-butadiene)Poly(1-vinylethylene) 1,4-addition1,4-Poly( 1,3-butadiene)Poly(1-butene- 1,4-diyl)

21. 1.7.2 Vinyl Copolymers  Copolymers are polymers derived from more than one species of monomer.  The IUPAC recommends source-based names for copolymers. Systematic: Poly[styrene-co-(methyl methacrylate)] Concise: Copoly(styrene/methyl methacrylate) SystematicConcise Poly[styrene-alt-(methyl methacrylate)]Alt-copoly(styrene/methyl methacrylate) Polystyrene-block-poly(methyl methacrylate)Block-copoly(styrene/methyl methacrylate) Polystyrene-graft-poly(methyl methacrylate)Graft-copoly(styrene/methyl methacrylate) poly(methyl methacrylate) is grafted onto a polstyrene backbone. Systematic Poly[styrene-co-butadiene-co-(vinyl acetate)] Copoly(styrene/butadiene/vinyl acetate) (a copolymer of the three named monomers with no specified distribution of repeating units) Concise Polystyrene-block-polyisoprene-block-polystyrene Block-copoly(styrene/isoprene/styrene)

22. 1. 7. 3 Nonvinyl Polymers  Nomenclature of nonvinyl polymers is much more complicated. IUPAC name: poly(oxycarbonyloxy- 1,4- phenyleneisopropylidene- 1,4-phenylene)

23. 1. 7. 4 Nonvinyl Copolymers  The IUPAC also recommends source-based nomenclature for nonvinyl copolymers.  A copolyester formed, for example, from a 2 : 1 : 1-molar ratio of the monomers ethylene glycol, terephthalic acid, and isophthalic acid could be named most simply, Poly(ethylene terephthalate-co-ethylene isophthalate)  A copolyamide prepared from a mixture of 6-aminohexanoic acid and 11–aminoundecanoic acid would be called by either of the following names: Poly[(6-aminohexanoic acid)-co-(11-aminoundecanoic acid)] Poly[(6-aminohexanoamide )-co-(11-aminoundecanoamide)]  7. 5 End Groups  End groups are not normally named

24. 1.8 Industrial Polymers 1.8.1 Plastics  Plastics are divided into two major categories on the basis of economic considerations and end use: commodity and engineering.

25. Plastics  Thermosetting plastics

26. 1. 8. 2 Fibers  Fibers are characterized by having high strength and modulus, good elongation (stretchability) good thermal stability (enough to withstand ironing, for example), spinnability (the ability to be converted to filaments), and a host of other properties depending on whether they are to be used in textiles, tire cord, rope and cable, and so on.  There are two principal natural fibers: cotton and wool, the former the polysaccharide cellulose, and the latter a protein.  World production of cotton is roughly five times that of wool on a weight basis.  World production of all fibers exceeds 30 million metric tons a year, with approximately 50% being synthetic.  Synthetic fibers are classified as cellulosic and noncellulosic.  Polyester and nylon account for about 70% of the total.

27. Fibers  Principal Synthetic Fibers

28. 1. 8. 3 Rubber (Elastomers)  Principal Types of Synthetic Rubber

29. Stress-strain behabior

30. 1. 8. 4 Coatings and Adhesives  Coatings  Would paint by any other name be as sweet  Efforts to reduce VOC (volatile organic carbon)  Adhesives  Would glue by any other name be as sticky  Efforts to reduce VOC (volatile organic carbon) 1.9 Polymer Recycling