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POLYETHYLENE. Monomers to Polymers. POLYETHYLENE. Created from the ethylene monomer. A thermoplastic (can be melted down and re-used) over 60M tons are produced worldwide every year. POLYETHYLENE. Polyethylene is created through polymerization of ethylene (C 2 H 4 ). . POLYETHYLENE.
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POLYETHYLENE Monomers to Polymers
POLYETHYLENE • Created from the ethylene monomer. • A thermoplastic (can be melted down and re-used) • over 60M tons are produced worldwide every year
POLYETHYLENE • Polyethylene is created through polymerization of ethylene (C2H4).
POLYETHYLENE • There are many different forms of polyethylene. • CHAINS:
POLYETHYLENE • BRANCHED:
POLYETHYLENE • CROSS-LINKED:
POLYETHYLENE Polyethylene is classified into several different categories based mostly on its weight and branching These both determine its properties.
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)
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
HDPE (high density polyethylene) • Linear - (stronger) • More tensile strength(doesn’t deform easily) • Lower ductility(breaks easily) • More expensive to make USES: • Sandwich bags • Laundry detergent bottles • Grocery bags
LDPE (low density polyethylene) • Branching (weaker) • Lower tensile strength(deforms easily) • Higher ductility(doesn’t break easily) • Molecules are less tightly packed • Cheapest/easiest to make • USES: • wash bottles • Saran wrap • most common = dry-cleaning bags