POLYETHYLENE

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POLYETHYLENE

• Monomers to Polymers

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POLYETHYLENE

• Created from the ethylene monomer.
• A thermoplastic (can be melted down and re-used)
• over 60M tons are produced worldwide every year

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POLYETHYLENE

• Polyethylene is created through polymerization of
  ethylene (C2H4).

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POLYETHYLENE

• There are many different forms of polyethylene.
• CHAINS

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POLYETHYLENE

• BRANCHED

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POLYETHYLENE

• CROSS-LINKED

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POLYETHYLENE

• Polyethylene is classified into several different
  categories based mostly on its weight and
  branching
• These both determine its properties.

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POLYETHYLENE

• UHMWPE (ultra high molecular weight PE)
• HDPE (high density PE)
• HDXLPE (high density cross-linked PE)
• PEX (cross-linked PE)
• MDPE (medium density PE)
• LDPE (low density PE)
• LLDPE (linear low density PE)
• VLDPE (very low density PE)

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POLYETHYLENE

• UHMWPE ultra high molecular weight polyethylene
• Extremely long chains
• Linear
• Very packed
• Tough material
• Highest impact strength
• bulletproof vests
• orthopedic implants (artificial hips, knees)
• ice-less skating rinks

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HDPE (high density polyethylene)

• Linear - (stronger)
• More tensile strength (doesnt deform easily)
• Lower ductility (breaks easily)
• More expensive to make
• USES
• Sandwich bags
• Laundry detergent bottles
• Grocery bags

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LDPE (low density polyethylene)

• Branching (weaker)
• Lower tensile strength (deforms easily)
• Higher ductility (doesnt break easily)
• Molecules are less tightly packed
• Cheapest/easiest to make
• USES
• wash bottles
• Saran wrap
• most common dry-cleaning bags