Poly many mer units Polymers are many units

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“Poly” = many “mer” = units Polymers are many units called monomers that can

“Poly” = many “mer” = units Polymers are many units called monomers that can be easily connected into long chains. They are giant molecules usually with carbons building the backbone.

POLYMERS (the whole train) are made out of MONOMERS (individual cars of the train)

POLYMERS (the whole train) are made out of MONOMERS (individual cars of the train) joined together.

Ü Polymer: High molecular weight molecule made up of a small repeat unit (monomer).

Ü Polymer: High molecular weight molecule made up of a small repeat unit (monomer). Ü A-A-A-A-A-A-A-A-A-A-A-AÜ Monomer: Low molecular weight compound that can be connected together to give a poymer

Natural Vs Synthetic Polymers

Natural Vs Synthetic Polymers

Cotton fiber is mostly cellulose, and cellulose is made of chains of the sugar,

Cotton fiber is mostly cellulose, and cellulose is made of chains of the sugar, glucose linked together a certain way.

Natural Polymers – found in nature and can be extracted ÜSilk ÜNatural Rubber ÜAmber

Natural Polymers – found in nature and can be extracted ÜSilk ÜNatural Rubber ÜAmber ÜWool ÜMolecules of life: proteins and DNA

Natural Polymers

Natural Polymers

Properties of Natural Polymers Properties of plastics : - Breaks Down more easily v

Properties of Natural Polymers Properties of plastics : - Breaks Down more easily v Wool is good heat insulator v Silk is satiny texture v Cotton – good air circulation and absorption of moisture v

Synthetic Polymers derived from crude oil and made by scientists ÜVelcro ÜSpandex ÜKevlar ÜPolyester

Synthetic Polymers derived from crude oil and made by scientists ÜVelcro ÜSpandex ÜKevlar ÜPolyester ÜNylon ÜSaran

Range of Synthetic Polymers Ü Traditionally, the industry has produced two main types of

Range of Synthetic Polymers Ü Traditionally, the industry has produced two main types of synthetic polymers – plastics and rubbers. Ü Plastics are (generally) rigid materials Ü Rubbers are flexible materials which exhibit long- range elasticity.

Properties of Synthetic Polymers Properties of plastics : - Light v Strong v Easily

Properties of Synthetic Polymers Properties of plastics : - Light v Strong v Easily molded and shaped and be coloured v Inert (unreactive) to chemical v Insulators of electricity and heat v Cheap v Able to resist corrosion v Special properties can be made according to specific needs v

Human and Environmental Impact The Pros and Cons

Human and Environmental Impact The Pros and Cons

Positive Impacts of Synthetic Polymers Ü Manufacturing: of plastic articles involving less energy than

Positive Impacts of Synthetic Polymers Ü Manufacturing: of plastic articles involving less energy than that necessary for the same production from traditional materials Ü Fuel Consumption: lightweight properties reduce fuel consumption in vehicles and space travel Ü Construction: non-corrosive plastics play a major role in the construction Ü Medical: Artificial limbs Ü Environmental: New Research for Oil Spills Ü Convenience: Everyday items (toothbrush, shower curtain) Ü Sports: Improvement to equipment and performance Ü http: //www. youtube. com/watch? v=cmlun. Cb. BV_o

The Negative Impacts of Synthetic Polymers Disposal problems Most of the polymers are non-biogradeable

The Negative Impacts of Synthetic Polymers Disposal problems Most of the polymers are non-biogradeable Cannot be decomposed by bacteria / decomposer So… caused disposal problem when polymer not decay Derived from Oil –non-renewable resource – Blockage of rivers Plastics items discarded Blockage of drainage systems & rivers Diseases Polymer containers not buried in the ground Become breeding ground for mosquitoes

Harmful to animals The non-biogradeable polymers thrown into rivers -> lakes -> seas Swallowed

Harmful to animals The non-biogradeable polymers thrown into rivers -> lakes -> seas Swallowed by aquatic animals Animals die due to choking https: //youtu. be/d 2 J 2 qd. Or. W 44 Pollutions Open burning of polymers Released harmful, poisonous gases Cause air pollution Contributes to acid rain

What you can do? 1. Recycle 2. Avoid the use of single use plastics

What you can do? 1. Recycle 2. Avoid the use of single use plastics 3. Plastics can be burned as fuel 1. Use degradable plastics

CATEGORY Code Example DENSITY 1 PETE Pop bottle Peanut butter jar Mylar 1. 38

CATEGORY Code Example DENSITY 1 PETE Pop bottle Peanut butter jar Mylar 1. 38 – 1. 39 2 HDPE Milk jug Shampoo bottle 0. 95 – 0. 97 3 V 4 LDPE Trash bags Diaper liners 0. 92 – 0. 94 5 PP Indoor/outdoor carpeting, kitchenware 0. 90 – 0. 91 6 PS Styrofoam Pen casing Clear plastic cups 1. 05 – 1. 07 7 OTHER Toothpaste and cosmetic containers Pipes and fittings, pill bottles, shower curtains, garden hoses, tile, leather like luggage and upholstery 1. 15 – 1. 35

Polymer structures Linear, Branched, Crosslinked

Polymer structures Linear, Branched, Crosslinked

Things that are made of polymers look, feel, and act depending on how their

Things that are made of polymers look, feel, and act depending on how their atoms and molecules are connected. Some are rubbery, like a bouncy ball, some are sticky and gooey, and some are hard and tough, like a skateboard.

By using different starting materials and processing techniques, we can produce polymers having different

By using different starting materials and processing techniques, we can produce polymers having different molecular structures

Linear Polymer Ü Microwaveable food containers, Teflon, Garden Hoses, Dacron carpets and Kevlar ropes.

Linear Polymer Ü Microwaveable food containers, Teflon, Garden Hoses, Dacron carpets and Kevlar ropes. Sturdy and rigid structure. Ü In reality, the number of monomer units in a polymer commonly ranges from 1, 000 to 10, 000 or more.

Branched Polymer Ü Soft, flexible due to looser structure. Shampoo and ketchup bottles and

Branched Polymer Ü Soft, flexible due to looser structure. Shampoo and ketchup bottles and milk jugs, plastic food wrap. To find some other examples, look on food containers and other plastics for the LDPE (low-density polyethylene)

Cross-linked Polymer Ü Lightly cross linked – flexible rubber. Heavily cross linked the more

Cross-linked Polymer Ü Lightly cross linked – flexible rubber. Heavily cross linked the more rigid and hard plastic. Two or more long chain polymer chains connected by chemical bonds that are not easily broken. Silly putty, Car Tires, Bowling balls.

Plastics are sudivided into Elastomers Thermoplastic Thermoset

Plastics are sudivided into Elastomers Thermoplastic Thermoset

Elastomer Polymer that can regain its original shape after being stretched or pressed at

Elastomer Polymer that can regain its original shape after being stretched or pressed at room temperature. Fancy word for Rubber

Range of Polymers Üthermoplastics and thermosets

Range of Polymers Üthermoplastics and thermosets

Thermosets Ü Extensive cross-linking formed by covalent bonds. Ü Bonds prevent chains moving relative

Thermosets Ü Extensive cross-linking formed by covalent bonds. Ü Bonds prevent chains moving relative to each other. Ü Material that cures or hardens when heated. Ü Chemical resistance, thermal stability, and overall durability

Thermoplastics (80%) Ü No cross links between chains. Ü Weak attractive forces between chains

Thermoplastics (80%) Ü No cross links between chains. Ü Weak attractive forces between chains broken by warming. The Material softens (becomes pliable when heated and can be remoulded. Ü. Therefore can be melted down and recycled

Range of Polymers Ü Another way of classifying polymers is in terms of their

Range of Polymers Ü Another way of classifying polymers is in terms of their form or function

Polymerisation The chemical process that joins the monomers together Addition Polymerisation Condensation Polymerisation Uses

Polymerisation The chemical process that joins the monomers together Addition Polymerisation Condensation Polymerisation Uses of polymers

Addition Polymerisation l Many molecules of monomers are added together l A monomer has

Addition Polymerisation l Many molecules of monomers are added together l A monomer has to have a double bond –alkene l Only the polymer is produced (no other product)

Polyethene / Polyethylene Monomer: ethene

Polyethene / Polyethylene Monomer: ethene

Ethylene has two carbons; plus, instead of the two carbons sharing just one electron

Ethylene has two carbons; plus, instead of the two carbons sharing just one electron each, they share two electrons each. High temperature or UV light can cause two of these shared (paired) electrons to become unshared (unpaired). H H C C H H - - - - H unpaired. Helectrons are These eager to pair up with another electron. If this. Cethylene molecule C bumps another ethylene molecule, the unpaired electrons will cause H it bumped H into to lend one the one of its inner electrons. - -

Here’s another way to see the chain reaction. These are the carbon atoms with

Here’s another way to see the chain reaction. These are the carbon atoms with their double-bond (2 shared electrons each). The hydrogen atoms are not shown. A collision breaks the first bond. Once the first double bond is broken, a chain reaction will occur. In about a second an entire chamber of compressed ethylene gas turns into the polymer, polyethylene.

Polyvinylchloride l Monomer: vinyl chloride

Polyvinylchloride l Monomer: vinyl chloride

Addition Polymerisation You are expected to be able to do the following things with

Addition Polymerisation You are expected to be able to do the following things with addition polymers: l Predict the repeating unit of the polymer given the monomer l Predict the monomer from the polymer – displayed formula l Pg 102 # 1, 2, 3

Condensation Polymers l Involves 2 monomers that have different functional groups. l They also

Condensation Polymers l Involves 2 monomers that have different functional groups. l They also involve the elimination of water or another small molecule (ex. H 2 O, HCl) l Monomer A + Monomer B Polymer + small molecule (normally water - dehydration). l Common condensation polymers include polyesters (the ester linkage) and polyamides (the amide linkage as in proteins).

Polyester is a another copolymer. It is made from equal amounts of two different

Polyester is a another copolymer. It is made from equal amounts of two different monomers. Polyester is used to make bottles and fabrics.

Recall: Esterification Reaction

Recall: Esterification Reaction

Polyester is made from the two monomers, terephthalic acid (note: “ph” is silent) and

Polyester is made from the two monomers, terephthalic acid (note: “ph” is silent) and ethylene glycol (car antifreeze). This makes a popular plastic called PETE, which is short for Polyethylene Terephthalate. The synthesis is also a dehydration reaction because water is given off. PETE O H O C ESTER groups formed Hence the name POLYESTER

Polyesters l The ester linkage is formed between the monomers of a diol and

Polyesters l The ester linkage is formed between the monomers of a diol and a diacid.

Polyamides l These involve the linkage of two monomers through the amide linkage as

Polyamides l These involve the linkage of two monomers through the amide linkage as in proteins (e. g. nylon, kevlar)

Polymers: Proteins Polymerization of a protein: putting simple monomers together. monome r Where will

Polymers: Proteins Polymerization of a protein: putting simple monomers together. monome r Where will the monomers JOIN TOGETHER?

Polymers: Proteins Polymerization of a protein: putting simple monomers together. monome r Where will

Polymers: Proteins Polymerization of a protein: putting simple monomers together. monome r Where will the monomers JOIN TOGETHER?

Polymers: Proteins Polymerization of a protein: putting simple monomers together. Water drops out to

Polymers: Proteins Polymerization of a protein: putting simple monomers together. Water drops out to allow the bonds to form.

Polymers: Proteins Polymerization of a protein: putting simple monomers together.

Polymers: Proteins Polymerization of a protein: putting simple monomers together.

Nylon 6, 6 a polyamide

Nylon 6, 6 a polyamide

Nylon-6, 6

Nylon-6, 6

Kevlar a polyamide

Kevlar a polyamide

Uses of polyamides l The main use of polyesters and polyamides is as fibres

Uses of polyamides l The main use of polyesters and polyamides is as fibres in clothing. l Most clothing now has a degree of manufactured fibres woven into the natural material (such as cotton). l This gives the material more desirable characteristics, such as stretchiness, and better washability. l Pg. 111 # 1, 2, 3