3.12 Polymers

• Polymers are a topic in A-level chemistry, specifically for the Tau exam board.
• in landfill and it's not very sustainable and it produces greenhouse gases and there's a risk of water contamination as well so it's not the best option for disposing of polymers and plastics.
• Poly alkyne switches polythene for example is an addition polymer, which are saturated molecules, do not have any polarity, and are pretty unreactive.
• Addition polymers are used in products such as carrier bags, and it is important to reuse these items to reduce waste in landfill.
• Polymers are not generic resources, they are dedicated to A-level chemistry students studying for the Tau exam board.
• Companies that incinerate waste have to install flue gas scrubbers to neutralize the acidic gas and turn it into a salt which can be collected later.
• Incineration is the burning of waste plastics and the energy from this can be used to generate electricity.
• Most polymers are not biodegradable and need to be recycled.
• PVC, which is polyvinyl chloride, is used in windows and if burned releases harmful HCL gas.
• Polymer chains can be broken up, a process known as cracking, and the monomers can be used as organic feedstock for other plastics.
• Some plastics like polypropene can be remoulded into new objects.
• Recycling plastics reduces dependency on crude oil as it means plastics can be melted down and remoulded into something new.
• Polymers cover a range of topics from addition polymers to condensation polymers.
• Condensation polymers are split into three main types: polypeptides, polyamides, and polyesters.
• Plastics can be contaminated with other materials, making them difficult to recycle.
• It's difficult to remake the original plastic from recycled materials, often requiring changes to its structure.
• Recycling preserves non-renewable raw materials such as crude oil.
• Recycling reduces the reliance on landfill.
• Recycling plastics is cheaper than making them from scratch.
• The sorting of recyclables is expensive and labor-intensive.
• Condensation polymerization is a process where two different monomers with at least two functional groups react together, forming a link and eliminating water.
• Polypeptides are found in proteins, polyamides are found in diamonds and dicarboxylic acids, and polyesters are formed by reacting dials and dicarboxylic acids together.
• A repeat unit is formed by the joining of two monomer units.
• In nylon 6-6, the repeat unit is formed by the joining of hexane dioic acid and 1,6-diaminohexane.
• The ester link in polyesters is different from the amide link in polyamides.
• The repeat unit in polyamides is OAH and H.
• Nylon 6-6 is used in ropes, carpets, clothing, parachute fabric, and other durable materials due to its strength and robustness.
• Terylene is an example of a polyester used in plastic drinks bottles.
• The reaction that forms polyesters is a condensation polymerization, which removes water from the molecules and forms the polyester.
• Polyesters are made from carboxylic acids and an alcohol, and are esterified when dicarboxylic acids are reacted with dials.
• Polyester is produced from a dicarboxylic acid and diol, while polyamide is produced from a diatomic silicic acid and diol.
• The molecule requires only one water molecule.
• Kevlar is a condensation polymer and is much stronger than any addition polymer.
• Condensation polymers can interact with each other, increasing their strength.
• Condensation polymers can interact with polar solvents like water, making them more susceptible to attack and therefore break down more readily in soil.
• Condensation polymers like polyester and polyamides are polar and hence susceptible to attack from nucleophiles, making them biodegradable and broken down by hydrolysis.
• Synthetic polymers are made from monomer units and are used to make a range of items such as plastic bottles, Teflon, and smart watches.
• The molecule has a trailing bond coming out the side, represented by '2 NH 2 O'.
• Condensation polymers are usually more rigid and stronger than addition polymers.
• Polyamides are formed by reacting dicarboxylic acids with dye together, and the link formed is an amide link.