Blow Moulding Process

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Blow Moulding Process Barrier Containers Part
1.3 Basic Polyethylene Chemistry
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Basic Polyethylene Chemistry

• Nomenclature
• Identification parameters for polyolefins
• Effect of variation of above parameters on
  finished items
• Additives
• Testing/Standards

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Vocabulary

• Monomer Comonomer
• Thermoplastic Thermoset
• Polymerization Polymer
• Homopolymer Elastomer
• Copolymer Initiator
• Terpolymer Catalyst
• Polyolefins Telomer

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Monomers

• E T H Y L E N E
• P R O P Y L E N E
• B U T E N E
• H E X E N E
• O C T E N E

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Polymerization reaction

• Initiator
• Catalyst
• Telomer

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Major features
Abbreviation

• Molecular weight
• Density
• Molecular weight distribution
• Molecular structure

MW
D
MWD
MS
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Molecular weight
high
low
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Molecular Weight

• Toughness
• Tenacity

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Scheme of Melt Flow Indexer

• Test conditions for PE
• T 190C
• load 2.16 - 5 - 10 - 21.6 kg
• time 10 minutes
• MI g/10 min/190C/load

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Melt flow index
HMW
Low melt flow index
LMW
High melt flow index
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Influence of melt flow index

• Flow and mouldability
• ESCR
• Resistance to rupture
  (impact, fall, traction)
• Gloss
• Heat resistance

MFI
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Density

• Rigidity
• Stiffness
• Cristallinity

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Density
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Influence of density

• Rigidity
• Resistance to rupture
• Heat resistance
• ESCR

D
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Molecular weight distribution
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Molecular weight distribution
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Molecular weight distribution

• - Processability
• - Transformation
• - Conversion

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Influence of molecular weight distribution
MWD is...
Narrow
Broad
Tenacity Gloss Impact resistance
Processability
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Molecular structure comparison

• PE-LD
• PE-LLD
• PE-HD
• METALLOCENE

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Viscosity
Increase
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Viscosity
MWD
MW
Viscosity
Molecular structure
D
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Use of additives

• ADDITIVES ABBREVIATIONS
• SLIP AGENT SLIP
• ANTIBLOCKING AGENT AB
• ANTIOXIDANT AO
• U.V. STABILISER UV
• COLOURING (PIGMENTS) --
• ANTISTATIC --
• ANTIFOG --
• CARBON BLACK --
• X-LINKING AGENT XL
• BLOWING AGENT --
• CLING AGENT --
• FLAME RETARDANT FR
• MOULD RELEASE AGENT --
• PROCESSING AID --
• BRIGHTENER --