small introductive presentation of plasticizers for plastics/polymers

1. PLASTICIZER
By
1
Amar Arakh

2. PLASTICIZER
 Chemicals that are added to other polymeric
substances, to improve the flexibility of the
polymer or to aid in processing the polymer.
 Additive designed to space out the polymer
molecules, facilitating their movements and
leading to enhanced flexibility (lower modulus)and
ductility. Widely used to convert PVC from the rigid
to the flexible variety. Can sometimes be
polymeric.
 The main role of the plasticizer is to improve
mechanical properties of the polymers by
increasing flexibility, decreasing tensile strength
and lowering the second order transition 2
temperature

3. CONT...
 Mostly used in PVC (second largest material selling in
Western Europe).
 80-90% plasticizers are used in PVC.
 The Successful addition of a plasticizer will result in
the formation of a product with a degree of
flexibility, such as a cable insulation or sheathing, a
floor covering or flexible profile.
 Plasticizers acts to reduce the Tg of PVC .
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4. PLASTICIZER MARKET
 6 million ton plasticizer produced every year.
 80-90% of the worldwide consumption is in PVC
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5. MECHANISM.......
 As plasticizers usually possess relatively long alkyl chains,
they have the effect of screening the polymer chains from
each other, thereby preventing them from re-forming the
chain-chain interactions which give the unplasticized polymer
its rigidity.
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6. PLASTICIZATION THEORIES
 Lubricity Theory: Plasticizer acts as a lubricant,
reducing intermolecular friction between polymer
molecules responsible for rigidity of the polymer.
 Gel Theory: Polymers are formed by an internal
three-dimensional network
 Free Volume Theory: Plasticizer lowers the glass
transition temperature (Tg) of the polymer.
 Mechanistic Theory: Plasticizer molecules are not
bound permanently to the polymer molecules form.
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7. CLASSIFICATION
 Majority of plasticizers are Organic Esters.
According to technique of Plasticization
External Internal
Not physically bound to Group constituting a part
polymer & can of a basic polymer chain, 7
evaporate, migrate or which may incorporate
exude from polymer. bet. chain

8. CLASSIFICATION
 Other
Conventionally classified as
Primary Secondary
Sufficient level of
Limited compatibility & can
compatibility to be used
exude if used alone.
give desirable effect. 8
Incorporate with primary
directly interact with
plasticizer.
chain.

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10. PHTHALATES
 Most widely use as plasticizer.
 Phthalates accounts 92% of all plasticizers.
 A Phthalate ester derived from phthalic acid by an
esterification reaction.
 Properties: Colorless Oily liquid ( like vegetable oil)
Ester odor, High boiling point, Inert and very stable over
long periods
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11. DOP/DEHP
 Primary use as plasticizer.
 Insoluble in water, Boiling point: 386.9oc,Density:
0.9732 g/L, Molecular weight: 390.5618 g/mol.
 Production: Phthalic anhydride with 2-ehaxenol:
C6H4(CO)2O + 2 C8H17OH → C6H4(CO2 C8H17)2 + H2O
 Used in medical devices ,Toys, Pacifiers, Vinyl
Upholstery, Food containers, Table cloths, Shower
curtains.
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12. DINP
 Mixture of chemical compounds consisting of various
isononyl esters & phthalic acid.
 Properties :Insoluble in H2O,Soluble in most organic
solvents, Boiling point: 250Density: 0.98g/cc, Molecular
weight: 418.6 g/mol.
 Use in Replacing DEHP in toys when initially
determined to be carcinogenic.
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13. DIDP
 Mixture of compounds derived from the esterification of
phthalic acid & isomeric decyl alcohol.
 Properties: density:0.96g/cc, melting point: -50, boiling
point: 250-257c at 0.5KPa.
 Uses in plastisol application, provides good initial
viscosities & excellent viscosity stability.
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14. SEBACATES & ADIPATES
 Dibutyl Sebacate is an organic chemical , a dibutyl ester of
sebacic acid.
 Properties: density: 0.94g/cc, boiling point:344.5c , melting
point:-10c, flash point: 178c.
 Used in food packaging industry, in plastics used for medical
devices, and for pharmaceutical applications,
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15. TRIMELLITATE PLASTICIZERS -
 Synthesized using one mole of trimellitic anhydride and 3
moles of an alcohol. The third alkyl group, compared to
phthalates, contributes higher molecular weight (low
diffusivity);the third ester group contributes sufficient polarity
to enhance compatibility with PVC.
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Tri (2-ethylhexyl) Trimellitate

16. FATTY ACID ESTERS
 Esters of fatty acids & monocarboxylic acids can be
used as viscosities depressant for PVC pastes &
also as secondary plasticizers for plasticized PVC.
 Present in liquid form.
 Stearic acid esters are used as plasticizers &
processing agent for various plastics & also as
lubricants for PS.
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17. OLIGOMERIC/POLYMERIC PLASTICIZER
 These extend the life of PVC products considerably
 They reduce migration, extraction & volatility.
 In these adipates are generally used in mixture with
other plasticizer to increase plasticization & improve
low temp. Properties.
 Epoxied plasticizer (soybean oil & linseed oil) are
used as stabilizing plasticizer offering properties of
migration resistance in PVC compounds.
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18. PLASTICIZER IN PVC
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19. SELECTION CRITERIA
 Choice of plasticizer depends upon the properties
required in final product, the application technology
used to make it !!
 Prize boundaries present for product process.
 Stability in processing & service condition.
 Compatibility & ease of mixing.
 Toxicity. 19

20. PLASTICIZER EFFICIENCY..
 The measure of concentration of plasticizer require
to improve a specifies softness to PVC.
 Plasticizer efficiency increases as carbon number
of alcohol chain decreases.
 For phthalates,
BBP>DIHP>DOP>DINP>DIDP
 Linear plasticizer is more efficient.
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21. HEALTH & SAFETY...
• First plasticizer
1860
• Phthalates Introduced
1930
• DEHP Declared Carcinogenic
1980
• IARC Re-classifies DEHP as non-
1998 carcinogenic
• European Parliament calls for
2001 alternatives to phthalates 21

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