Polymer Physics Overview

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Polymer PhysicsOverview Lecture Notes
1Lecture 1

• Dr. Anthony Brennan
• University of Florida
• Department of Materials Science Engineering

2
Syllabus and Schedule

• Syllabus
• Schedule
• Proposal
• UF Honesty Policy
• Turn-it In Program
• Course Webpage
• EMA 6165 Website
• E-learning Website
• Questions?

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Agenda

• Introduction Chapter 1
• Definitions/Nomenclature
• Configurational States
• Structure/Property Relationships
• Polymer Classifications
• Molar Mass Distribution
• Thermal Transitions (General)

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Properties

• Chemical
• Physical
• Electronic
• Magnetic
• Optical

CERAMICS
METALS
PROPERTIES
ELECTRONIC MATERIALS
POLYMERS
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Polymer

• macromolecules formed by combining large numbers
  of low molar mass molecules
• molar mass exceeds 10 kg/mol for reasonable
  properties

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Vocabulary

• Polymer
• monomer (repeat unit)
• oligomers
• Bond energies
• Reactions
• Condensation Polymerization
• Addition Polymerization
• Chain Growth
• Structure
• Thermoplastics
• Thermosets
• Elastomers

• Chain Structure
• Homopolymer
• Copolymer
• Branching
• Stereoregular
• Isomeric
• Molar Mass
• Number, Weight Ave
• Degree of polymerization (DP)
• Polydispersity (PDI)

Refer to Table 2.7 Intro to Polymer Sci 4th
Ed, L. H. Sperling, Wiley Sons, 2006
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Polymer Chain Structure

• linear chain
• homopolymer
• random copolymer
• branched chain
• homopolymer
• copolymer

• block copolymer
• AAAAABBBBB
• star polymer
• comb
• graft chain
• copolymer

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Polymer Chain Composition

• homopolymer
• condensation
• AA BB
• AB
• addition
• A

• copolymer
• random
• alternating
• block
• graft

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General Classification of Polymers

• Thermoplastic
• Thermoset
• Rubber
• Elastomers
• Natural Macromolecules

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Thermoplastic vs. Thermoset

• Thermoplastic
• can be formed with heat/pressure/time
• recyclable
• crystalline or non-crystalline

• Thermoset
• can be formed with heat/pressure/time once
• not recyclable!

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Rubber and Elastomers

• Rubber
• butadiene, isoprene
• cross linked structure
• high strength
• high recovery

• Elastomers
• Thermoplastic
• Thermoset
• lightly cross linked
• high elongation (gt400)

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Importance of ChemistryProtein Tertiary
StructureConformational Structure
Random Confirmation - Dilute
Helical Configuration - Tertiary
Lamellar Configuration - Secondary
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Importance of Chemistry

• Balance of Three Energies
• Intermolecular
• Intramolecular
• Thermal (kT)
• Structures
• Linear
• Branched

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Polymer PhysicsOverview Lecture Notes
1Lecture 2

• Dr. Anthony Brennan
• University of Florida
• Department of Materials Science Engineering

15
Characteristic Bonds
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Tg -123C, Tm -60C
Tg -120C Tm 140C
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Tg -120C Tm 140C
Tg 55C Tm 265C
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Tg 55C Tm 265C
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Polymer PhysicsOverview Lecture Notes
1Lecture 3

• Dr. Anthony Brennan
• University of Florida
• Department of Materials Science Engineering

20
Isomerism "Isomers"

• The same chemistry, but different architecture,
  i.e., arrangement of atoms
• Types of Isomers
• Optical (Chem Draw alanine)
• Stereo
• Geometric
• Substitutional

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Configuration - Symmetry
Chem Draw Pro Isobutane
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Asymmetry 2,4-dimethyl pentane
file 2,4-dimethylpentane
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Optical Isomers Amino AcidsAlanine
Chiral Center
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Configurational States

• Configuration - permanent stereostructure.
  Rearrangement requires bond disruption.

• Tacticity
• Isotactic
• Syndiotactic
• Atactic

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Configurational States

• Configuration - permanent stereostructure.
  Rearrangement requires bond disruption.

• Tacticity
• Isotactic
• Syndiotactic
• Atactic

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Configurational States

• Configuration - permanent stereostructure.
  Rearrangement requires bond disruption.

• Tacticity
• Isotactic
• Syndiotactic
• Atactic

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Stereochemistry

• Optical
• Polypropylene oxide
• Stereoisomers
• Isotactic
• Syndiotactic
• Atactic

• Geometric isomers (dienes)
• poly(1,2- butadiene)
• syndio, iso, atactic
• poly(2,3- butadiene)
• cis trans
• Head to Head
• Head to Tail

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Chain architecture
"Branched" or "graft
Blend
Net
Block or triblock
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Copolymer Chain Terminology
Unknown/specified -co- poly (A-co-B)
Statistical -stat- poly(A-stat-B)
Random -rand- poly(A-rand-B)
Alternating -alter- poly(A-alter-B)
Block -block- poly(A-block-B)
Graft -graft- poly(A-graft-B)
Star -star- poly(A-star-B)
Blend -blend- poly(A-blend-B)
Cross-linked -net- poly(A-net-B)
Interpenetrating -inter- poly(A-inter-B)
Adapted from Intro Phys Poly Sci-Sperling, 4th
Ed, Wiley Sons
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Importance of Chemistry

• Copolymers
• Random
• Block
• Graft
• Star
• Ionomers
• Telechelic
• Polyelectrolytes

• Molar Mass
• Distribution
• Viscosity
• Creep
• Stability
• Processability
• Networks
• Irreversible
• Reversible

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Polymer PhysicsOverview Lecture Notes
1Lecture 4

• Dr. Anthony Brennan
• University of Florida
• Department of Materials Science Engineering

32
Synthetic Processes

• Condensation
• Addition
• Chain Growth
• Anionic/Cationic

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Polymerizations

• Condensation polymerization
• Loss of low molar mass molecule(s)
• e.g. Polyethyethylene Terephthalate (PET)
• Addition polymerization
• radical reaction
• e.g. Polyethylene (PE)

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Condensation PolymerizationStep Growth Process

• Monomer Monomer Dimer
• Monomer Dimer Trimer
• Monomer Trimer Tetramer
• Dimer Trimer Pentamer
• n-Mer m-Mer (n m) Mer

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Characteristics

• Condensation polymerization
• stepwise reaction
• monomer consumed early
• DP rises steadily
• long reaction time gives high molar mass PDI
  2
• monomers, dimers, trimers, etc. present
• reaction by products

• Addition polymerization
• chain reaction
• one group added per reaction
• DP peaks instantly
• long reaction time gives high conversion PDI
  40
• only polymer and monomer present
• no reaction by products

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Condensation Polymers

• Lexan - poly(bisphenol A carbonate)
• Mylar, Dacron - poly(ethylene terephthalate)
• Nylons - polyamides
• Kevlar, Nomex - poly(arylamide)
• Kapton - (polyimide)

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Condensation Polymers

• Nylon 6,6
• A-A Monomer adipic acid
• B-B Monomer 1,6 hexane diamine
• A Monomer End group
• B Monomer

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Condensation Polymers

• Poly(bis phenol A carbonate)
• A-A Monomer Bis phenol A
• B-B Monomer phosgene
• A Monomer End group

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Condensation Polymers

• Kevlar
• A-A Monomer
• terephthalic acid
• B-B Monomer
• p-phenylene diamine
• A Monomer
• End group
• Nomex
• A-A Monomer
• isophthalic acid

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Chain Growth Polymer

• Nylon 6
• A-A Monomer caprolactam
• A Monomer
• B Monomer

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Addition Polymerizations

• Initiation
• Propagation
• Termination
• combination
• disproportionation

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Addition Polymerization
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Addition Polymers

• polyethylene (PE, HDPE, LDPE, LLPE)
• polystyrene
• polypropylene
• polyacrylamide
• polyacrylate, polyacrylic acid, polymethyl
  methacrylate

• polybutadiene
• polyisoprene
• polybutene
• polyvinylchloride
• polytetrafluoroethylene (Teflon)
• polyethylene-co-propylene-co-butadiene (EPDM)

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Polymerization Processes

• Solution
• Bulk
• Emulsion
• Suspension
• Interfacial
• Supercritical

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Summary

• Thermoplastics, thermosets and elastomers
• Condensation, addition, chain growth, and ionic
• Condensation kinetics slow
• Condensation polydispersity is high
• Addition polymers exhibit stereisomerism
• Composition control is critical

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Additional References

• Macromolecules, An Introduction to Polymer
  Science, F. A. Bovey, F.H. Winslow, ed, Academic
  Press (1979) ISBN 0-121-19755-7
• Fundamental Principles of Polymeric Materials,
  2nd Edition, Stephen L. Rosen, Wiley Interscience
  (1993) ISBN 0-471-57525-9
• Polymer Science and Technology, Joel R. Fried,
  Prentice Hall PTR (1995) ISBN