Polymeric Materials
Sunan Tiptipakorn, D.Eng.
Department of Chemistry,
Faculty of Liberal Arts and Science,
Kasetsart University, Kamphaen Saen Campus,
Nakorn Phathom, 73140 Thailand.
Introduction
Material Science
Relationship
Performance
StructureProcessingProperties
Materials
Semiconductors
MetalsPolymers
- organic polymers- inorganic polymers
CeramicsComposites
Polymers
Thermoplastics
Thermosetting
- can be recycledExample:- PE, PP, PVC
-can not be recycledExample:- polyurethane, epoxy
- no melting temp.
Ref.: http://cltad.arts.ac.uk
Ref.: http://www.emeraldinsight.com
Ref.:http://www.resinsystems.com/products/highvoltageinsulators.html
Organic Polymers
Main Organic Polymers
6 types of well known thermoplastics
http://commons.wikimedia.org/wiki/File:Extruder_section.jpg
http://www.synaflex.com/Products/ExtrudedRubberProducts
Extruder
Polyethylene (PE)
PE granules: (1)Natural form, (2) and (3) are colored with dyes
Ethylene monomer polyethyleneor
orRef.:http://www.yurak.com
(Ethene) (polyethene)
Ref.: www.thaigoodview.com
HDPE (High Density Polyethylene)
high crystallinity (Linear PE)Ref.:www.hdpe-containers.com/pipette-droppers.htm
LDPE (Low Density Polyethylene)
Low crystalinity (Branched PE)
Ref.: http://www.waterwiseliners.co.za/Pondimages/ldpe%20pond.JPG
Ref.:http://www.makingthemodernworld.org.uk/learning_modules/chemistry/03.TU.02/?section=7
Branched Chains and Linear Chains
Free Radical Polymerization
Ref.: http://pslc.ws/mactest/radical.htm
High Temp.High Pressure
LDPEPVCPS
Examples:-
Ziegler and Natta Catalyst
TiCl4 + Aluminium co-catalyst
Examples:HDPE, PP
Coordination Polymerization
Low TemperatureLow Pressure
Ref.: http://chem.chem.rochester.edu/~chem421/zn.htm
Polypropylene (PP)
Ref.: www.vcharkarn.com/varticle/38233/2
Ref.:http://www.chemicals-technology.com/projects/hmcpolymers-thailand/
Ref.:http://www.steinwall.com/ART-polypropylene.html
Three Types of Polypropylene
Polystyrene (PS)
Types of Polystyrenes
Polyvinyl chloride
Polymerization: free
radical
chain
polymerization
Morphology: highly
amorphous,
~11%
crystallinity
Glass
transition temperature:
~84
oC
Ref.:http://www.vcharkarn.com/varticle/38233/2
Polyethylene terephthalate (PET)
Ref.:http://www.vcharkarn.com/varticle/38233/2
Organic Polymers
- Low performance @ high Temp.- Swelling organic solvent- Flexibility @ low range of Temp.- Low flame resistance- Not suitable for artificial organs
Drawbacks
Low Cost / AffordabilityElectrical InsulationAbrasive ResistanceEasiness to ProcessLight-weight
Benefits
Inorganic Polymers
1) Addition of Side GroupsMethodology
Addition polymerization of vinyl monomer
C CXH
H H Vinyl monomer
Steric effect
Free Radical Polymerization
ExamplesX = SiCH3 ; OSiCH3 ; C6 H5 PO
Coordination Polymerization
1) Addition of Side Groups (cont.)
Acrylonitrile
Vinyl monomer
Methyl Methacrylate
StyreneCopolymer with
2) Coordination polymerizationof organometallic reagent
with organic polymer (e- donor)
M
M = inorganic
Example
Coordination bonding
3) Synthesis via polymers withinorganic substance in main chain3.1 Non-metallic inorganic substances
(Si, P, S, O, N)
3.2 Transition metalsMainchain
ExamplesPoly(organosiloxane) or SiliconePhosphazene polymerMetallo-backbone polymer
Polyorganosiloxane (Silicone)
Most commonly used : poly(dimethylsiloxane)
(CH3)2SiCl2
Si
O
Si
CH3
H3C O
H3C
CH3
O Si
O
Si
CH3
CH3
CH3
CH3
H2O
-HCl
octamethylcyclotetrasiloxanehydrolysis
acid or base
O Si
CH3
CH3
npoly(dimethylsiloxane)
(MW > 25,000)
O2 penetration: artificial organs
dimethyldichlorosilane
Phosphazene Polymer
Conductive Polymer N PR
R nn> 15000
Raw Materials: PCl5 + NH4 Cl
Ring-opening polymerizationMacromoleular substitution reactionDirect condensation
N PR
R nn> 15000
Phosphazene Polymer (cont.)
R changes Properties changes
Cl - Inorganic rubber- Organic solvent swelling- Reacted with water
OCH2 CF3 - water resistant
Applications: Dyes, gasket, O-ring, and etc.
Natural
Inorganic Polymers
CharacteristicsThree dimensional structureRigid and Brittle
AsbestosRef.: http://www.treehugger.com/2009/06/14-week/
Silicate
Silica glass
Ref.:http://beachcomberonsaipan.blogspot.com
Natural Inorganic Polymers
Ref.: http://minerals.caltech.edu/Silica_Polymorphs/index.html
PolysilicateTetrahedral structure
Silicic acid
-4H2 O
Ref.: http://commons.wikimedia.org/wiki/File:Silicic_acid.jpg
Si OHHO
OH
O- Na+
Condensation
http://minerals.caltech.edu/Silica_Polymorphs/index.html
Most well known polysilicate : Silica (SiO2 )
Amorphous
Crystalline:
Quatz
Tridymite
Cristobalite
Molecular Alignments of Tetrahedral Moleculesin Various Patterns of (SiO4 )4-
Zeolite
Crystalline aluminosilicate
http://img.alibaba.com/photo/10872242/Zeolite_From_Indonesia.jpg
(SiO4 )4- and (AlO4 )5-Polysilicate aliminate
To Soften water; act as catalyst in petrochemical plants
Tetrahedral
Basic Zeolite Structure
Ref.: http://www.cheresources.com/zeolitezz.shtml
Ref.:http://www.moutere.com/stories/storyReader$39
Legend: Circle = Oxygen, Square = Silicon, aluminium
Tetrahedral
Ionomer Main chain: Hydrocarbon or Fluorocarbon
Na+
http://www.jsce.co.kr/polymer_lecture/ionomer.html
Side chain: Carboxylic or sulfonic group
Ref.: http://www.jsce.co.kr/polymer_lecture/ionomer.html
Ref.: http://www.jsce.co.kr/polymer_lecture/ionomer.html
Primer Coating
http://www.honeypixel.com/clients/inglewood/index.php?page=news-item-1
Applications of Ionomers
Golf ball
http://www.wemixallup.com/car-center-f35/car-paint-detailing-research-t180.htm
Ceramics
Ceramics Compounds ofSilicatesOxidesCarbidesNitridesAluminates
Strong covalent bond with network structureHigh strength and modulusHigh thermal Resistance
Brittle
Ref.:http://www.ttc.most.go.th/
Ref.:http://www.selectcon.com/Ref.:http://www.ceramickitchenware.com/
Manufacturing Steps
Sintering@ High Temperatureand High Pressure
Milling to micron scale
Ref.: http://sandblastingabrasives.com/
Ref.: http://www.thaiceramicsociety.com/pc_burn_oxygen.php
Sol-gel Process
1. Mixing metal with alcohol to form metal alkoxide
Ti + C2 H5 OH Ti(OCH2 CH3 )(s) + 2H2
2. Dissolving metal alkoxide and mixing with water
Ti(OCH2 CH3 )(solution) + 4H2 O Ti(OH)4(s) +4C2 H5 OH
3. Dehydrating Ti(OH)4 with acid or baseTi + H2 O Complex of Titanium Oxide and hydroxide
Three dimensional network…..Gel
4. Burning gel @ 200-500oC
Ceramic Composites
Ceramics + Additives
Increase Toughness
Cutting machine, Grinding wheel
Ceramic Fiber of SiC or carborundum
Polydimthyl silane Ceramic Fiber400oC
Sintering@1200oCto removeH2 and C atom
CeramicsAlumina: Circuit Board
Ref.:http://dea.brunel.ac.uk/cleaner/Electronics_Projects/Handbook_2.htm
SiC:Abrasive resistant materials
http://www.gravescompany.com/cabmate.htm
Quartz: piezoelectricRef.: http://www.britannica.com/EBchecked/topic-art/636716/108321/Typical-components-of-a-quartz-watch
La-Ba-Cu:Superconducting Ceramic
Piezoelectricity is the ability of some materials to generate an electric
field or electrical potential in response to applied mechanical stress.
Ref.:http://wever.wordpress.com/2008/07/
Reinforcing Elements
Glass Fiber
Cellulose Fiber
Carbon Fiber
Aramid Fiber or Kevlar
Pure Resin
Carbon Fiber
Most commonly used Acrylic Fiber: Polyacrylonitrile
300oC
http://www.psrc.usm.edu/macrog/carfsyn.htm
Step 1
Step 2
http://www.psrc.usm.edu/macrog/carfsyn.htm
Step 3
http://www.psrc.usm.edu/macrog/carfsyn.htm
http://www.psrc.usm.edu/macrog/carfsyn.htm
Step 4
Thermoplastic Elastomer
Thermoplastic Elastomer
Copolymer Behaviors:Melt when heating (Thermoplastics)Elastic (Elastomer)
Example
Butadiene + High Impact Polystyrene
Ref.: http://pslc.ws/macrog/kidsmac/rubber.htm
PS Butadiene PS
SBS Rubber
Polystyrene = tough hard plastic durability.Polybutadiene = rubbery material rubber-like properties.
http://pslc.ws/macrog/kidsmac/rubber.htm
References:
1. Schaffer J.P. et al., The Science and Designof Engineering Materials, R.D. Irwin Inc.,Chicago, 1995.
2. Allen S.M. and Thomas e.L., The structureof materails, The MIT Series in Materials Scienceand Engineering, John Wiley and Sons. Inc.,New York, 1999.
3. Allcock H.R. and Lampe F.W.,Contemperary Polymer Chemistry, 2nd Ed., Prentice Hall, New York, Jersey, 1990.
Thank youfor your kind
attention