ADDITIVES FORADDITIVES FOR
PLASTICSPLASTICS
ADDITIVES FORADDITIVES FOR
PLASTICSPLASTICS
Characteristics of polymersCharacteristics of polymers
• Low densityLow density
• Low energy to processLow energy to process
• Corrosion resistantCorrosion resistant
• CheapCheap
1500
Rubber
1839
Vulcanization
1907
Bakelite1917
X-ray Cellulose
1920
Polymerization
1927
Vinyl chloride
1930
Polystyrene
1938
Nylon
1941
Polyethylene
1970
Ekonol
1971
Kevlar
1976
Replace metals
Polymer DegradationPolymer Degradation
Various processes degrade polymerVarious processes degrade polymer
Deteriorate propertiesDeteriorate properties
AppearanceAppearance
Types of polymer degradationTypes of polymer degradation
1- Thermal degradation (Temp.)1- Thermal degradation (Temp.)
2- Thermo-oxidative degradation (Temp., O2- Thermo-oxidative degradation (Temp., O22))
3- Photodegradation (Light)3- Photodegradation (Light)
4- Photo-oxidative degradation (Light, O4- Photo-oxidative degradation (Light, O22))
5- Mechanical degradation (stresses)5- Mechanical degradation (stresses)
6- Chemical degradation (strong acid & base)6- Chemical degradation (strong acid & base)
7-Biodegradation (bacteria, fungi)7-Biodegradation (bacteria, fungi)
8- Degradation by high energy radiation8- Degradation by high energy radiation
Polymers additivesPolymers additives
Fillers ColorantsFillers Colorants
Plasticizers Impact modifiersPlasticizers Impact modifiers
Lubricants Coupling agentsLubricants Coupling agents
Flame retardants Antistatic agentsFlame retardants Antistatic agents
Photostabilizers AntiozonantsPhotostabilizers Antiozonants
Heat stabilizers Curing agentsHeat stabilizers Curing agents
Blowing agents ComptabilizersBlowing agents Comptabilizers
Polymer additivesPolymer additives
RetardRetard
degradationdegradation
ModifyModify
propertiesproperties
PolymerPolymer
SynthesisSynthesisProcessingProcessing
DesignDesign
End useEnd use
Polymer AdditivesPolymer Additives
SolidSolid
LiquidLiquid
RubberRubber
GasGas
Features of additivesFeatures of additives
1- Efficient1- Efficient
2- Cheap2- Cheap
3- Non toxic3- Non toxic
4- Stable under processing conditions4- Stable under processing conditions
5- Stable under service conditions5- Stable under service conditions
6- Should not bleed6- Should not bleed
FillersFillers
1- To extend the bulk (lower the cost)1- To extend the bulk (lower the cost)
2- To modify mechanical properties2- To modify mechanical properties
3- To improve flame retardant properties3- To improve flame retardant properties
4- Electrical properties or insulation4- Electrical properties or insulation
5- visual properties and colour5- visual properties and colour
Mineral fillersMineral fillers
CaCOCaCO33 ClayClay SilicaSilica
CaCOCaCO33
Cost reductionCost reduction
Dimensional stabilityDimensional stability
Improve impact strenghImprove impact strengh
Surface uniformitySurface uniformity
ClayClay
Cost reductionCost reduction
Dimensional stabilityDimensional stability
Improve tensile strengthImprove tensile strength
Insulation & thermal stabilityInsulation & thermal stability
Glass (Glass (fibers &solid spheresfibers &solid spheres))
Cost reductionCost reduction
Dimensional stabilityDimensional stability
TranslucencyTranslucency
Carbon (Carbon (fibers &powderfibers &powder))
ChemicalChemical
resistanceresistance
CorrosionCorrosion
resistanceresistance
PlasticizersPlasticizers
Heat
Rigid polymerRigid polymer FlexibleFlexible
polymerpolymer
(T(Tgg))
Plasticizer (Plasticizer (liquid estersliquid esters))
Lower TLower Tmm
LowerLower TTgg
Increase flexibilityIncrease flexibility
Slection of plasticizerSlection of plasticizer
High compatibility with polymerHigh compatibility with polymer
Low volatility & migrationLow volatility & migration
Improve flexibility at low temp.Improve flexibility at low temp.
LubricantsLubricants
ExternalExternal InternalInternal
Wax, fatty acids, fatty amides & metallic stearatesWax, fatty acids, fatty amides & metallic stearates
External lubricantsExternal lubricants
Possess polar gpsPossess polar gps
Low compatibility with polymerLow compatibility with polymer
Form thin film between polymerForm thin film between polymer
& machine (prevent sticking)& machine (prevent sticking)
Internal lubricantsInternal lubricants
Sprayed on the surface of the moldSprayed on the surface of the mold
Flame retardantsFlame retardants
Fire triangleFire triangle
ClosedClosed
systemsystem
Energy (heat)Energy (heat)
Oxidizer (OOxidizer (O22))
Fuel (plastic)Fuel (plastic)
FuelFuel
Proper formProper form
(gas, vapour)(gas, vapour)
Proper amountProper amount
(flammable range)(flammable range)
OxidizerOxidizer
Proper formProper form
(gas, vapour)(gas, vapour)
Proper amountProper amount
(Important)(Important)
EnergyEnergy
Energy required to raise the tempEnergy required to raise the temp
of fuel to its ignition temp.of fuel to its ignition temp.
Shortcoming of fireShortcoming of fire
triangletriangle
Covalent bonded organic cpdCovalent bonded organic cpd
extinguished using dry chemicalsextinguished using dry chemicals
Tetrahedron of fireTetrahedron of fire
FuelFuel
Energy (heat)Energy (heat)
Oxidizer (OOxidizer (O22))
Fuel (plastic)
C
hain
reaction
C
hain
reaction
O
fburning
O
fburning
Combustion mechanismCombustion mechanism
CHCH44 + O+ O22 COCO22 + H+ H22OO
1- O = O 21- O = O 2 ..
OO ..
2- CH2- CH44 4 H. +4 H. + ....
CC....
3-3- ....
CC.. + ... + .
OO..
CO (flammable gas)CO (flammable gas)
4-4- ....
CC.. +.. +
22 ..
OO..
COCO22
5- 2H +5- 2H + ..
OO..
HH22OO
Fuel (covalent)Fuel (covalent)Fuel (covalent)Fuel (covalent)
Free radicalsFree radicalsFree radicalsFree radicals
OO22OO22
Free radicalsFree radicalsFree radicalsFree radicals
Flammable gases (CO)Flammable gases (CO)Flammable gases (CO)Flammable gases (CO)
FireFireFireFire++
PolymerPolymer
Volatile ProductsVolatile Products
(Free radicals)(Free radicals)
OO22
Compastible productsCompastible products
(Fire)(Fire)
++
Flame retardantsFlame retardants
Organic (phosphateOrganic (phosphate
esters, halogenatedesters, halogenated
cpd)cpd)
Inorganic (antimonyInorganic (antimony
oxide, Mg (OH)oxide, Mg (OH)22 ))
Flame retardantsFlame retardants
mechanismsmechanisms
Gas phaseGas phase Condense phaseCondense phase
PolymerPolymer
Volatile ProductsVolatile Products
(Free radicals)(Free radicals)
OO22
Compastible productsCompastible products
(Fire) +(Fire) +
FlameFlame
retardantretardant
(Free radicals)(Free radicals)
StableStable
productproduct
Gas phaseGas phase
FlameFlame
retardantretardant
FreeFree
radicals(Cl.)radicals(Cl.)
Chain reactionChain reaction
brokenbroken
Fire goes upFire goes up
OO22 FreeFree
radicalsradicals
PolymerPolymer BreakingBreaking
C-C, C-HC-C, C-H
FreeFree
radicalsradicals
CombaComba
stiblestible
cpdcpd
FireFire
Condense phaseCondense phase
Flame retadantFlame retadant DecomposingDecomposing
polymerpolymer
++
Compatible cpdCompatible cpd
CharChar
Inorganic FlameInorganic Flame
retardantsretardants
Liberate waterLiberate water Non flam. gasesNon flam. gases
AntioxidantsAntioxidants
1-Chain breaking1-Chain breaking 2-Preventive2-Preventive
a-Metal deactivatora-Metal deactivator b-Peroxide decomposersb-Peroxide decomposers
Chain breaking antioxidantsChain breaking antioxidants
Oxidative degradationOxidative degradation
RR..
+O+O22 ROOROO..
InitiationInitiation RHRH + O+ O22 RR..
+HO+HO22
..
ROOROO..
++ RHRH RR..
+ ROOH+ ROOHPropagationPropagation
Chain breaking antioxidantsChain breaking antioxidants
Degenerate chainDegenerate chain
branchingbranching
ROOH ROROOH RO..
+ HO+ HO..
RORO..
++ RHRH RR..
+ ROH+ ROH
HOHO..
++ RHRH RR..
+ H+ H22OO
RR..
+ R+ R..
R-RR-R
RORO22
..
+ RO+ RO22
..
RR..
+ RO+ RO22
..
TerminationTermination
Chain breaking antioxidantsChain breaking antioxidants
ROOROO..
+ InH ROOH+ InH ROOH +In+In..
ROOROO..
+ In. Non radical+ In. Non radical..
OH
CH3
C(CH3)3(CH3)3C
+ ROO+ ROO..
O
CH3
C(CH3)3(CH3)3C
+ ROOH+ ROOH
O
CH3
C(CH3)3(CH3)3C
O
C(CH3)3C(CH3)3
CH3
OOR
+ ROO+ ROO..
O
C(CH3)3C(CH3)3
CH3
..
O
C(CH3)3C(CH3)3
CH3
..
Preventive antioxidantsPreventive antioxidants
Metal ion deactivatorMetal ion deactivator
ROOH + MROOH + Mn+n+
ROOROO..
+ M+ Mn+1n+1
ROOH + MROOH + Mn+1n+1
ROOROO..
+ H+ H++
+M+Mn+n+
ROOROO..
++ RHRH ROOHROOH + R+ R..
OH
CH N
NH
C
O
OH
CHN
NH
C
O
Cu
Preventive antioxidantsPreventive antioxidants
Hydroperoxide decomposersHydroperoxide decomposers
ROOH + (ArO)ROOH + (ArO)33P ROHP ROH + (ArO)+ (ArO)33P= OP= O
PosphitePosphite PosphatePosphate
PhotostabilizersPhotostabilizers
Oxidative degradationOxidative degradation
RR..
+O+O22 ROOROO..
InitiationInitiation RHRH RR..
+H+H..
ROOROO..
++ RHRH RR..
+ ROOH+ ROOHPropagationPropagation
hv
PhotostabilizersPhotostabilizers
Degenerate chainDegenerate chain
branchingbranching
RR..
+ R+ R..
R-RR-R
RORO22
..
+ RO+ RO22
..
RR..
+ RO+ RO22
..
TerminationTermination
ROOH ROROOH RO..
+ HO+ HO..
hv
PhotostabilizersPhotostabilizers
LightLight
screenscreen
UVUV
absorberabsorber QuenchersQuenchers
PhotostabilizersPhotostabilizers
Light screenLight screen
UVUV
Al powder on PE, ABSAl powder on PE, ABS
PhotostabilizersPhotostabilizers
UV absorberUV absorber
(Hydroxybenzophenon)(Hydroxybenzophenon)
UV absorberUV absorber**
Loss EnergyLoss EnergyHeatHeat
UV absorberUV absorber
PolymerPolymer
UVUV
PhotostabilizersPhotostabilizers
Quenchers [Ni(II) organic cpd]Quenchers [Ni(II) organic cpd]
Energy transfer between excitedEnergy transfer between excited
polymer and photostabilizerpolymer and photostabilizer
Quencher mechanismQuencher mechanism
UVUV
AA**
QQ
A+ QA+ Q** A+ QA+ QAA
AA** + Q+ Q
UVUV
AA**AA
[A…….Q][A…….Q]** A + QA + Q
Excited complexExcited complex
Heat stabilizersHeat stabilizers
(Diethyl tin maleats)(Diethyl tin maleats)
PVC Degradation mechanismPVC Degradation mechanism
Cl H Cl H Cl
CH2-CH-CH-CH-CH-CH
CH2-CH=CH-CH=CH-CH2Cl
O
(C C)
H H
O
(C C)
H H
H
Cl
++ HClHCl
MYMY22 + HCl+ HCl MYCl + HYMYCl + HY
MM == Ca, Zn, Ba, Cd, PbCa, Zn, Ba, Cd, Pb YY == organic anionorganic anion
Blowing agentsBlowing agents
To obtain cellular polymerTo obtain cellular polymer
1-Chemical cpd decompose in processing stage1-Chemical cpd decompose in processing stage
to volatile cpdto volatile cpd
2- Low boiling liquids volatilize during processing2- Low boiling liquids volatilize during processing
3-Diffusion of gas in polymer under pressure3-Diffusion of gas in polymer under pressure
4- Powdered solid CO4- Powdered solid CO22 with PVC pastswith PVC pasts
Comments on ChemicalComments on Chemical
Blowing agentsBlowing agents
1-Gases evolved within a narrow temp range1-Gases evolved within a narrow temp range
2- Decomposition temp range should be2- Decomposition temp range should be
suitable for polymersuitable for polymer
3-Gas evolved should not corrode processing3-Gas evolved should not corrode processing
machinemachine
ColorantsColorants
Materials which provide color in polymerMaterials which provide color in polymer
DyesDyes
(Soluble(Soluble)
PigmentsPigments
(insoluble(insoluble)
OrganicOrganic
(C-Black)(C-Black)
InorganicInorganic
(TiO(TiO22 ))
ColorantsColorants
Organic Dyes & PigmentsOrganic Dyes & Pigments Inorganic PigmentsInorganic Pigments
•BrightBright
•BurnBurn
•Add in small quantityAdd in small quantity
•Very complex cpdVery complex cpd
•More expensiveMore expensive
•Small particle sizeSmall particle size
•OpaqueOpaque
•Flame retaddantFlame retaddant
•Resist light & heatResist light & heat
•Low conc. produceLow conc. produce
translucent colortranslucent color
•FeO, CoO, CdSFeO, CoO, CdS
Curing AgentsCuring Agents
Additives that cause crosslinking of the polymersAdditives that cause crosslinking of the polymers
curing
agent
S
Curing AgentsCuring Agents
• Captax (2-Mercaptobenzothiazole)Captax (2-Mercaptobenzothiazole)
• Santocure (2-Mercaptobenzothiazole sulfonamide)Santocure (2-Mercaptobenzothiazole sulfonamide)
Vulcanization of SBRVulcanization of SBR
Curing AgentsCuring Agents
• Initiators (Benzoyl Peroxide)Initiators (Benzoyl Peroxide)
Curing of polyestersCuring of polyesters
Curing AgentsCuring Agents
• Gama Ray or UVGama Ray or UV
Produce Polymer Free RadicalsProduce Polymer Free Radicals
Curing of the polymerCuring of the polymer
Curing AgentsCuring Agents
H H H H H H
C C C C C C
H H H H H H
H H H H H H
C C C C C C
H H H H H H C
C
C
..
C
..
UV
Curing AgentsCuring Agents
• OO22 + Heavy metals (Co, Pb, Mg)+ Heavy metals (Co, Pb, Mg)
Curing of unsaturatedCuring of unsaturated
polymerspolymers
Curing AgentsCuring Agents
H H H H H H
C C C C C C
H H H H H H
H H H H H H
C C C C C C
H H OOH H H H
OO22
H
H
H
H
H
H
C
C
C
C
C
C
H
H
O
..
H
H
H
CoCo
3+3+ ++
-- OHOH
CoCo
2+2+
Antistatic AgentsAntistatic Agents
(Antistats)(Antistats)
InsulatingInsulating
materialsmaterials
DustDust
attractionattraction
SparkingSparking
Build electricBuild electric
chargecharge
Antistatic agent reduce static charge buildAntistatic agent reduce static charge build
on the polymer surfaceon the polymer surface
Antistatic AgentsAntistatic Agents
Dissipation of staticDissipation of static
chargecharge
Applied to surfaceApplied to surface
More conductiveMore conductive
surfacesurface
Attract moistureAttract moisture
from airfrom air
Reduce static chargeReduce static charge
on the surfaceon the surface
Act as a lubricant onAct as a lubricant on
polymer surfacepolymer surface
Ex: Quaternary amm cpd,Ex: Quaternary amm cpd,
esters of fatty acids &esters of fatty acids &
polyhydric alcoholpolyhydric alcohol
Impact modifiersImpact modifiers
RigidRigid
matrixmatrix
RubberRubber
Impact modifiersImpact modifiers
Improve resistance of materials toImprove resistance of materials to
stress (impact)stress (impact)
Elastomers :Elastomers : ABS, BS, MBS, ChlorinatedABS, BS, MBS, Chlorinated
PEPE (absorb energy at room temp.)(absorb energy at room temp.)
CompatibilizersCompatibilizers
RigidmatrixRigidmatrix
RubberRubber Phase separationPhase separation
CompatibilizersCompatibilizers
Compounds provide miscibility orCompounds provide miscibility or
compatibility to materials that arecompatibility to materials that are
immiscible or only partially miscibleimmiscible or only partially miscible
Homogeneous product does notHomogeneous product does not
separate into its componentsseparate into its components
Phase 1Phase 1
Phase 2Phase 2
Compatibilizer MechanismsCompatibilizer Mechanisms
Physical bond at interfacePhysical bond at interface
Reactive CompatibilizationReactive Compatibilization
PolymerPolymer PolymerPolymerCompatibilizerCompatibilizer
PolymerPolymer PolymerPolymerCompatibilizerCompatibilizer
Chemical bondChemical bond
Coupling agentsCoupling agents
Resin matrixResin matrix
FibersFibers
Coupling agentsCoupling agents
Used as surface treatment in composites toUsed as surface treatment in composites to
improve the interfacial bond between theimprove the interfacial bond between the
matrix(weak) and fiber(strong)matrix(weak) and fiber(strong)
Silans and TitanateSilans and Titanate
AntiozonantsAntiozonants
Degradation(OzoneDegradation(Ozone
cracking on surface)cracking on surface)
Unsaturated polymersUnsaturated polymers
OO33
Cracking of rubberCracking of rubber
tires and hosestires and hoses
AntiozonantsAntiozonants
C= CC= C
OO33
C= O + C= OC= O + C= O
Degraded rubberDegraded rubber
C CC C
OO OO
OO
AntiozonantsAntiozonants
Scavenge OScavenge O33 atat
surface beforesurface before
reaction withreaction with
polymerpolymer
Reacted withReacted with
degraded productdegraded product
preventing morepreventing more
degradationdegradation
N,N-disubstituted p-phenelene diamine, phenol, sulfar cpdN,N-disubstituted p-phenelene diamine, phenol, sulfar cpd
AntiozonantsAntiozonants
WaxesWaxes
Inhibit ozoneInhibit ozone
deteriorationdeterioration
Migration toMigration to
polymer surfacepolymer surface
Less susceptibleLess susceptible
coatingcoating
AntiozonantsAntiozonants
WaxesWaxes ++ N,N-disubstituted p-pheneleneN,N-disubstituted p-phenelene
diaminediamine (very effective ozone protection)(very effective ozone protection)
Wax assists in diffusion of antiozonantWax assists in diffusion of antiozonant
to polymer surfaceto polymer surface
Additives for plastic_ii+(3)

Additives for plastic_ii+(3)