1Introduction to Polymer Chemistry
411317 Polymer Chemistry (2/2552)
by Dr. Walaiporn Prissanaroon-OuajaiDept. of Industrial Chemistry, KMUTNB
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
2POLYMER CHEMISTRY - WHAT IS IT ?
Chemistry of large molecules
1980
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
3What are polymers ?
Why are polymers important ? Extraordinary range of
physical properties Many (not all) are cheap
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
4Polymer contains repeating units
Polymers vs. Macromolecules
A polymer is a macromolecule.but a macromolecule may not be a polymer
Polypropylene (PP)n
Macromolecules contain no repeating units
Ex. Protein, DNA
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
5 Packaging/films (PE, PP, PET) Everyday household stuff Paint (Polyacrylate, Epoxy) Adhesives (Epoxy resin, Acrylic resin) Auto's,aerospace,etc. Fibres (polyester, nylon) Electronic applications Elastomers (Rubber, Butadiene)
Applications
ABS
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
6Plastics and the Environment ?
From The Poison Plastic published byGreenpeace (www.greenpeace.org):
Most common plastics pose serious threats to human health and the environment.
extreme pollution from production toxic chemical exposure during use hazards from fires (CxHy + O2 CO2 + H2O) their contribution to the
worlds growing waste crisis.
http://www.pcd.go.th/info_serv/waste_rubbish.htm ()411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
7Ages ago Natural fibers Ex. wool, silk and cotton
1492 Columbus discovered South America and found the use of natural rubber (Hevea brasiliensis)
Historical background
Uses: Latex coatingPolyisoprene
Crying treesPara rubber
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
8Vulcanization transformation of hevea rubber to elastomer (valcanized rubber)
1839 Charles Goodyear
1st synthetic plastic made from natural polymer
1843 Nelson Goodyear
Ebonite High % vulcanization (rubber:S = 100:32)
S8
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
91848 - Menard Cellulose Nitrate
Synthetic polymers started!!
1st artificial thermoplastic
1846 Parkes and Hyatt CelluloidCellulose Nitrate + Camphor (as plasticizer)
use in photographic industry
highly flammable compound
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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1905 - Baekeland Bakelite
1st truly synthetic plastic
not soften by heat
Phenol
Formaldehyde
Phenol-Formaldehyde resin
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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1920s - Staudinger Macromolecule hypothesis
Nobel prize - Chemistry 1953
Demonstrations of Both natural & synthetic polymers
Polymer is Giant molecule not aggregate like colloid or cyclic compound long chain-like molecule formulated a polymeric structure for rubber,
based on a repeating isoprene unit
1927 PVC1931 PMMA & Neoprene1938 Nylon1941 LDPE
1943 Silicone1947 Epoxy resins1948 ABS1957 HDPE
Development of commercial polymers
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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Classification of polymers1. By source1.1 Natural polymers (including macromolecules)
cis-polyisoprene (natural rubber)
glycosidic linkage
Polysaccharide Ex. starch, glycogen, cellulose, chitin, chitosan(C6H10O5)n-1 where n = 300 and 3000.
-NHCO-CH2 for chitin-NH2 for chitosan
Protein(Polyamide)
Ex. plastics, synthetic rubbers, synthetic fibers ect.1.2 Synthetic polymers
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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2.1 Condensation polymerization (from bi/polyfunctional monomers)
2. By polymerization reaction (for synthetic polymers)
Dimer Monomer
Ester bond
[C-(CH2)n-C-O-(CH2)m-O]
O O polyester
Ex. Polyamide, polyurethane, polycarbonate, ect.
Step-growth polymerization
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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2.2 Chain-growth polymerization (from unsaturated hydrocarbons or olefins )
Ex. poly(vinyl alcohol), PTFE, poly(vinyl acetate), PMMA ect.
X XXXX
[CH2-CH2]
[CH-CH2]n
n
[CH-CH2]Cl
n
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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3. By composition
3.1 Homopolymers (contain one type of repeat unit)
[CH2-CH2] [CH-CH2]OH
n n
3.2 Copolymers (contain at least 2 repeat units)Ex. Styrene-Butadiene-Styrene block copolymer (SBS)
Thermoplastic Elastomer
Ex. Acrylonitrile-butadiene-styrene copolymer (ABS)
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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4.1 Linear chain with 2 ends
4.2 Cyclic - chain with no end
4.3 Branched polymers have side chains
4.4 Dendritic (or dendrimer) - tree-like molecule
4.5 Network (or crosslinked) 3D structures which each chain is
connected to others
4. By skeletal structure
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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Strain (e) = DLL0
Deformation Stress Strain
5. By application
In case solid See mechanical properties-
Strain
Stress Flexible plastics
FiberRigid plastics
Elastomer
Emulsion
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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6.1 Thermoplastics - Soft (and melt) and formable when heated- Rigid when cooled - Can be re-heated and re-formed into different shapes
6. By thermal behavior
Recycled plastics
6.2 Thermosetting plastics - Initially form a X-linked solid with by heating- Soft (not melt) when 2nd heated but cannot re-shaped
Melamine-formaldehyde resins
Epoxy resins
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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Biodegradable polymers
Conducting polymers
Specific classes of polymers
PLA
PHBPCL
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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Nomenclature of PolymersSource-based name: base on name of monomer
Structure-based name: base on structure of repeat unit
Poly + name of monomer Note: use ( ) if monomer has a multi-worded name
Poly(name of structure of repeat unit)
CH2=CH2
CH=CH2OH
CH=CH2CH3
Monomer Polymer Source-based nameStructure-based name
In UK called polythene
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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IUPAC recommendation for source-based names of polymers1. Homopolymer Poly+name of monomer
For multi-worded monomer namePoly(name of monomer)or
Polyethylene(PE)
Polypropylene(PP)
Polystyrene(PS)
Poly(vinyl chloride)(PVC)
Polytetrafluoroethylene(Teflon)
1.1) Addition polymers
Most common polymer. Used in bags,wire insulation, and squeeze bottles
Fibers, indoor-outdoor carpets, bottles
Styrofoam, molded objects such as tableware (forks, knives and spoons),trays, videocassette cases.
Clear food wrap, bottles, floor covering,synthetic leather, water and drain pipe
Nonstick surfaces, plumbing tape,chemical resistant containers and films
(or ethylene)
(or propylene)
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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1.1) Addition polymers (continued)
Polyacrylonitrile(Acrilan, Orlon, Creslan)
Polychlorprene(neoprene rubber)
Poly(vinyl acetate) (PVA)
PolyisopreneNatural rubber
Styrene butadiene rubber (SBR)
Poly(methyl methacrylate)(Lucite, Plexiglas) Glass replacement, paints, and
household products
Fibers used in knit shirts,sweaters,blankets, and carpets
Adhesives (Elmers glue), paints,textile coatings, and chewing gum
Rubber bands, gloves, tires, conveyor belts, and household materials
Oil and gasoline resistant rubber
Non-bounce rubber used in tires
(or isoprene)
(or chloroprene)(2-chloro-1,3-butadiene)
(copolymer)411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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1.2) Condensation polymers
Polyamides(nylon)
Polyesters(Dacron, Mylar, Fortrel)
Polyesters(Glyptal resin)
Polyesters(Casting resin)
Fibers, molded objects
Linear polyesters, fibers,recording tape
Cross-linked polyester, paints
Cross-linked with styrene and benzoyl peroxide, fiberglass boat resin, casting resin
(from condensation polymerization)
(Thermoset)
(Thermoset)
(Thermoplastic)
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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Phenol-formaldehyde (Bakelite)
Cellulose acetate
Silicones
Polyurethanes
Mixed with fillers, molded electrical cases, adhesives, laminates,varnishes
Photographic film
Water-repellent coatings,temperature-resistant fluids and rubber
Foams, rigid and flexible, fibers
Note : Same repeat units and names can exhibit different chemical and physical characteristics, e.g. MW or MWD.
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)
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2. Copolymer
Poly(name of monomer A-co-name of monomer B)
Poly(propene-co-methacrylonitrile) Polyacrylonitrile-block-polybutadiene-block-polystyrene Poly[(acrylic acid)-ran-(ethyl acrylate)]Polyisoprene-graft-poly(methacrylic acid)
Ex.
Copoly(propene/methacrylonitrile) Block-copoly (acrylonitrile/butadiene/styrene) Ran-copoly (acrylic acid/ethyl acrylate) Graft-copoly (isoprene/methacrylic acid)
Alternative Format(Random)
411317 by Dr. Walaiporn Prissanaroon-Ouajai (IC-KMUTNB)