POLYMERS & PLASTICS. The term polymer comes from Greek words meaning "many parts". A polymer is a large molecule composed of repeating structural units. These units, called monomers, are connected by covalent chemical bonds. A polymer may be a natural or synthetic. POLYMERIZATION.
The term polymer comes from Greek words meaning "many parts". • A polymer is a large molecule composed of repeating structural units. • These units, called monomers, are connected by covalent chemical bonds. • A polymer may be a natural or synthetic.
POLYMERIZATION • Aprocess of reacting monomer molecules together in a chemical reaction to form polymer chains. • Chemicalgroups are lost from the monomers so that they may join together.
BIOPOLYMERS • Biopolymersare producedby living organisms. • Cellulose, starch and chitin, proteins and peptides, DNA and RNA arenaturalpoymers.
The most common organic compound on Earth is cellulose. • They havecharacteristic compact shapes which determine their biological functions. • Naturally decomposes in environment in the presence of bacteriasorlightandwatereasily.
SYNTHETICPOLYMERS • Chemicallymanufacturedfromseparatematerials. • Abundantly derivedfrom petroleum products. • Requires humanintervention.
PLASTICS • We live in plastic age now. • The dawn of the plastic era was in 1950s. • This was when we first started to use plastic for consumer goods on a mass scale.
Plastics are materials made of long strings of carbon and other elements. • Each plastic has been developed for a special purpose.
Types of plastics depend on : • the starting monomer selected, • the length of polymer chains, • the type of modifying compounds added.
THERMOPLASTICS soften with heat and harden with cooling. Examples : • Acrylic (Perspex) • Acrylo-nitrile (Nylon) • Polyethylene (Polythene) • Polypropylene • Poly Vinyl Acetate (PVA) • Poly Vinyl Chloride (PVC) • Polystyrene and ABS • PTFE (Teflon)
THERMOSETS are cured or hardened by heat. Examples: • Bakelite • Epoxy • Melamine • Polyester • Polyurethane
POLYETYLENE • Annual production of 80 million tonnes • Used as packacking and plastic bags
PVC • used in clothing and upholstery • make flexible hoses and tubing, flooring • electrical cable insulation • Used in waterbeds, toys, inflatable structures,…
POLYPROPYLENE Used in a wide variety of applications like: • Packagcing, textiles, • Loudspeakers • Automative components • Laboratory equipments • Polymer banknotes • And more…
POLYTETRAFLUOROETHYLENE • Brand name is Teflon • used as a non-stick coating for pans and other cookwares • used in containers and pipework for reactive and corrosive chemicals • Reduces friction, wear and energy consumption of machinery.
NYLON • first used commercially in a nylon-bristledtoothbrush(1938) • The first commerciallysuccessful synthetic polymer • used in so and so many applications.
WHYPLASTICS? • Hard, tough and slippery • Soft and rubbery • Good insulators of heat or electricity • Light weight and flexible • Hygienic, cheap and non-rusting • Easy to shape and colour
FACTS ABOUT PLASTIC PRODUCTION • Total production in the year 2009 is 100 million tones. • Total production was around 5 million tones in 1950s per year. • One tonne of plastics is equivalent to 20,000 two litre drinks bottles or 120,000 carrier bags.
FACTS ABOUT PLASTIC CONSUMPTION • Plastics consumption is growing about 4% every year in Europe. • Plastic consumption by fields is shown next:
The average American consumed 1.6 gallons of bottled water in 1976. • In 2006, that number jumped to 28.3 gallons. • Americans use 2.5 million plastic bottles every HOUR. • Every year we make enough plastic film to shrink-wrap the state of Texas.
PLASTIC DEGRADITION • Each plastic item could last in the environment anywhere between 400 to 1000 years. • Plastics do not biodegrade. • They photo degrade to breake down into smaller toxic bits.
A plastic milk jug takes 1 million years to decompose. • A plastic cup can take 50 - 80 years to decompose. • A newspaper takes 6 months in land or 2 months in sea to decompose.
PVC • A known human carcinogen. • Commonly used to package foods and liquids, ubiquitous in children's toys and teethers. • There is no ban in the use of PVC.
BISPHENOL A • Achemical compound primarily used to harden plasticproducts including water bottles even baby bottles. • Migratesfrom polycarbonate products into foods and beverages.
Even low doses of bisphenol A causes • Brain damage • Hyperactivity • increased fat formation • early puberty • disrupted reproductive cycles.
In 2002, 2.8 million tons was produced. • Today, our blood contains bisphenol A. • There was no bisphenol A in human blood before 1960s.
Any other types of plastics are carcinogen maybe less or more. • Another risk comes from food. • Especially sea food contains toxic materials due to plastic pollution in oceans.
Nearly every piece of plastic EVER made still exists today. • In land, there are huge garbage areas to dump plastic wastes. • Most damage is on the oceans and seas.
Oceanic Microplastics • Plastics break into tiny pieces and stays in the ocean. • Ingested by every single organism in the world's oceans up to krill and right up to the great Blue Whale. • As a result, plastic is transfered in the food chain.
Oceanic microplastics mix with the plankton. • A very heigh percentage of the worlds plankton feeders mistakenly inject it. • Scientists now nickname vast surface areas of the world's oceans as ‘’Plastic soup’’.
It's actually the stomach contents of one dead laysan albatross chick. • In 2001 a piece of plastic found in an albatross stomach bore a serial number that was traced to a World War II seaplane shot down in 1944.
About four-fifths of all marine litter comes from land by • wind or washed by rain off highways and city streets, • streams and rivers. Nearly 90% of floating marine litter is plastic.
An average of 46,000 pieces of plastic debris float on or near the surface of every square mile of ocean. • UK beaches have on average 2000 pieces of litter for every kilometer.
An estimated 14 billion pounds of trash, much of it plastic is dumped in the world's oceans every year. • The worldwide fishing industry dumps an estimated 150,000 tons of plastic into the ocean each year, including packaging, plastic nets, lines, and buoys.
EFFECTS ON MARINE ANIMALS • Thousands of seabirds choke or get tangled in plastic debris. • Plastic bag litter is lethal, killing many species including sea birds, whales, dolphins, seals, seal lions and turtles every year.
Ingestion of litter such as plastic bags can cause • physical damage, • mechanical blockage of the oesophagus and digestive system
This results in • a false sensation of fullness or satiation, as the litter may remain in the stomach. • This can lead to internal infections, starvation and death.
Plastic bags have been recorded as a cause of entanglement in marine animals. • Entanglement can restrict movement, leading to starvation, drowning or suffocation.
Exceptionally high concentrations of pelagic plastics, chemical sludge, and other debris that have been trapped by the currents of the North Pacific Gyre.
FACTS ABOUT RECYCLINGOF PLASTICS Today, Americans generate 10.5 million tons of plastic waste a year but recycle only 1 or 2 % of it.