The document discusses various methods used in compounding and molding of plastics. Compounding involves mechanically mixing additives like fillers, binders, plasticizers, stabilizers, and colorants into plastics without chemical reactions. Common molding techniques described are blow molding, injection molding, extrusion molding, compression molding, and transfer molding. Blow molding involves melting plastic then injecting and blowing air to force the plastic into a mold cavity. Injection molding melts and injects plastic into a mold under high pressure to form complex parts. Extrusion molding forces melted plastic through a die to form shapes.

1. COMPOUNDINGCOMPOUNDING

2. COMPOUNDING OF PLASTICSCOMPOUNDING OF PLASTICS
• The process ofThe process of mechanical mixingmechanical mixing ofof
variousvarious additivesadditives with plasticswith plastics without anywithout any
chemical reactionchemical reaction

3. FILLERS / EXTENDERSFILLERS / EXTENDERS
• Organic /inorganic compoundOrganic /inorganic compound
incorporatedincorporated
• Reduce the cost of the fabricated plasticReduce the cost of the fabricated plastic
article per unit weightarticle per unit weight
• Improve hardness,tensileImprove hardness,tensile
stregnth,opacity..stregnth,opacity..

4. FILLERSFILLERS
• PARTICULARPARTICULAR
• Mainly to reduce theMainly to reduce the
costcost
• Increases hardnessIncreases hardness
but not tensilebut not tensile
strengthstrength
• Eg. AsbestoseEg. Asbestose
increases heatincreases heat
resistanceresistance
• FIBROUSFIBROUS
• Enhance the tensileEnhance the tensile
strengthstrength
• Also called reinforcingAlso called reinforcing
fillersfillers
• Eg.C black to naturalEg.C black to natural
rubber increases T.S.rubber increases T.S.
by 40%by 40%

5. BINDERSBINDERS
• Hold the constituents of the plastic togetherHold the constituents of the plastic together
• Give the desired properties like plasticityGive the desired properties like plasticity
&electrical insulating properties&electrical insulating properties
• Eg.thermoplastic resins & thermosetting resinsEg.thermoplastic resins & thermosetting resins

6. PLASTICIZERSPLASTICIZERS
• To improve plasticity & flexibilityTo improve plasticity & flexibility
• To reduce the cracking on the surfaceTo reduce the cracking on the surface
• To reduce the temp.& pressure forTo reduce the temp.& pressure for
mouldingmoulding
• Are less volatile liquidsAre less volatile liquids
• Eg. Dibutyl phthalate,tributyl phosphate..Eg. Dibutyl phthalate,tributyl phosphate..

7. Plasticizer should be :Plasticizer should be :
• Miscible with polymerMiscible with polymer
• InertInert
• A high molecular weight, high boiling andA high molecular weight, high boiling and
non-volatile substancenon-volatile substance
DisadvantageDisadvantage
Reduce T.S. & chemical resistanceReduce T.S. & chemical resistance

8. STABILISERSTABILISER
• Compounds added to prevent theCompounds added to prevent the
degradation by air, UV rays & heatdegradation by air, UV rays & heat
• Eg. Phenyl salicylate to polythene, PVC…Eg. Phenyl salicylate to polythene, PVC…

9. CATALYSTS/CATALYSTS/
ACCELERATORSACCELERATORS
To accelerate theTo accelerate the
condensation ofcondensation of
thermosetting to getthermosetting to get
cross-linked pdt.cross-linked pdt.
Eg.benzoyl peroxideEg.benzoyl peroxide
COLOURANTSCOLOURANTS
To give a colour to the plasticTo give a colour to the plastic
Eg. Organic dyestuffsEg. Organic dyestuffs
LUBRICANTSLUBRICANTS
To make the moulding easierTo make the moulding easier
To impart finish to pdtTo impart finish to pdt
Eg. Oils, waxes, soapes…Eg. Oils, waxes, soapes…

10. ANTIOXIDANTANTIOXIDANT
• To prevent the oxidative degradationTo prevent the oxidative degradation
• Eg. PBNA (phenyl-beta-naphthylamine)Eg. PBNA (phenyl-beta-naphthylamine)

11. MOULDINGMOULDING
• MouldingMoulding is the process of manufacturingis the process of manufacturing
by shaping pliable raw material using aby shaping pliable raw material using a
rigid frame or model called arigid frame or model called a patternpattern..

12. Types of MouldingTypes of Moulding
– Blow mouldingBlow moulding
– Injection mouldingInjection moulding
– Extrusion mouldingExtrusion moulding
– Compression mouldingCompression moulding
– Transfer mouldingTransfer moulding

13. Compression MouldingCompression Moulding

14. Blow MouldingBlow Moulding

15. Process illustrationProcess illustration
• 11. The plastic is fed in granular form into a 'hopper' that. The plastic is fed in granular form into a 'hopper' that
stores it.stores it.
• 22. A large thread is turned by a motor which feeds the. A large thread is turned by a motor which feeds the
granules through a heated section.granules through a heated section.
• 33. In this heated section the granules melt and become a. In this heated section the granules melt and become a
liquid and the liquid is fed into a mould.liquid and the liquid is fed into a mould.
• 44. Air is forced into the mould which forces the plastic to. Air is forced into the mould which forces the plastic to
the sides, giving the shape of the bottle.the sides, giving the shape of the bottle.
• 55. The mould is then cooled and is removed. The mould is then cooled and is removed

16. Blow moulded productsBlow moulded products

17. 2. Injection Moulding2. Injection Moulding
Materials such as
polystyrene, nylon,
polypropylene and polythene
can be used in a process
called injection moulding

18. The ProcessThe Process

19. Injection MouldingInjection Moulding

20. INJECTION MOULDEDINJECTION MOULDED
COMPONENTSCOMPONENTS

21. EXTRUSION MouldingEXTRUSION Moulding

22. Extrusion MouldingExtrusion Moulding

23. EXTRUSION Moulding dieEXTRUSION Moulding die

24. TUBE EXTRUDEDTUBE EXTRUDED
COMPONENTSCOMPONENTS

25. Transfer MouldingTransfer Moulding

26. TRANSFER MOULDEDTRANSFER MOULDED
COMPONENTSCOMPONENTS