More Complex Polymers and Recycling

Different States Different parts of a plastic may be ordered or random

Different States Different parts of a plastic may be ordered or random Ordered is crystalline Random is a glass structure Since most polymers have a random structure –Cold – glass state –Warm – rubber state Glass transition temperature, T g, separates

T g ’s Polystyrene - 100°C – plastic utensils LDPE °C – soft plastics –Melts at 108°C Natural rubber – way below 0°C – tires Polyester - 73°C – non-wrinkle fabrics

Natural Rubber Monomer is cis - isoprene Slowly flows and is sticky 1839 – Charles Goodyear discovered vulcanization –X-linking with sulfur –Elastomer Synthetic rubber, hard and brittle – trans –True synthetic (cis) not until 1955

Monomers Natural rubber Neoprene Polybutadiene

Conducting polymers Alternating single and double bonds in chain –Example polyacetylene or polyethyne Conduction can be directional –Along chains but not across

Recycling Solid waste: 4 lbs / person per day –For 250 million people in US – 1 billion lbs/day Make up of garbage?

40 % by volume 20 % by volume

Recycling Solid waste: 4 lbs / person per day –For 250 million people in US – 1 billion lbs/day Make up of garbage? In order to recycle, 4 things needed: –Collection –Sorting –Reclamation –End-use Problems for plastic Problems for paper

Amount Recycled Aluminum cans – 65% Paper – 20% Glass – 10% Plastic – 3% - Why? –Economics –Sorting Plastic container codes

H14 – C5 16, , , , , 65, 73