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