Since the plastics utilized in a given manufacturing sector e. Recycled Plastics Recycle Code Abbreviation and Chemical Name of Plastic Types of Uses and Examples 1 PET - polyethylene terephthalate Many types of clear plastic consumer bottles, including clear, 2-liter beverage bottles 2 HDPE - High density polyethylene Milk jugs, detergent bottles, some water bottles, some grocery plastic bags 3 PVC - Polyvinyl chloride Plastic drain pipe, shower curtains, some water bottles 4 LDPE - Low density polyethylene Plastic garbage and other bags, garment bags, snap-on lids such as coffee can lids 5 PP - Polypropylene Many translucent or opaque plastic containers; containers for some products such as yogurt, soft butter, or margarine; aerosol can tops; rigid bottle caps; candy wrappers; bottoms of bottles 6 PS - Polystyrene Hard clear plastic cups, foam cups, eating utensils, deli food containers, toy model kits, some packing popcorn 7 Other Polycarbonate is a common type, Biodegradable, Some packing popcorn.
PET - polyethylene terephthalate. Many types of clear plastic consumer bottles, including clear, 2-liter beverage bottles. HDPE - High density polyethylene. Milk jugs, detergent bottles, some water bottles, some grocery plastic bags. PVC - Polyvinyl chloride. Plastic drain pipe, shower curtains, some water bottles. Related Audiobooks Free with a 30 day trial from Scribd. Views Total views. Actions Shares. No notes for slide. Disposal of Polymers 1. By Karl Coelho Disposal of Polymers 2.
There are 3 ways to dispose of polymers. Landfills Incineration Recycling Biodegradable Polymers 4. This uses up valuable land, and suitable sites often fill up quickly. Waste polymers are disposed of in landfill sites.
This uses up valuable land, suitable sites often fill up and quickly. Although some types of landfill can be used for other purposes once finished, they still require land while in use and restrict possible future uses of the land.
The more land used for landfill, the less available for agriculture, natural habitat and development. The conditions of landfill are such that the decomposition releases large quantities of dangerous gases, including methane, a potent greenhouse gas. The gas emissions contribute to air pollution and climate change. They are also a potential health hazard, not to mention being malodorous enough to constitute an ongoing nuisance to nearby communities. Modern methods, such as the use of landfill liners, can mitigate direct soil pollution to a certain extent.
However, the risk of pollutants leaching into the soil remains. Although hazardous wastes are supposed to go to purpose-built landfills, be incinerated or recycled, some inevitably ends up with general trash.
Batteries contain hazardous chemicals such as lead and often end up with general trash, simply because householders are unaware of proper disposal methods. Materials such as plastics, paper, metals and glass are recyclable. All organic materials can be composted into a rich soil. Wasting the materials by burying them in landfills means raw materials are continuously consumed, wasting energy and leading to serious habitat destruction.
Landfill sites also attract and support pests such as rats and cockroaches, some of which carry diseases. The associated noise, air and soil pollution impacts humans as well as wildlife.
They are also difficult to dispose of and need to be burned under special conditions to avoid the formation of extremely toxic combustion by-products such as dioxins.
Condensation polymers all contain either the amide or ester linkages. These linkages make the polymers reactive towards both acids and bases, which cause the polymer structure to break down.
This is called hydrolysis. This means that condensation polymers are biodegradable and do not pose the same pollution hazard as addition polymers.
This is a serious environmental issue because it destroys habitats, disrupts food chains and food webs, is a severe eyesore, and indirectly leads to increased carbon dioxide content in the atmosphere.
It could also lead to erosion of hillsides with the consequence of flooding. An obvious solution is to recycle these paper products. In this lesson, we will learn about recycling paper and the advantages and disadvantages of this industrial process.
Paper is in fact layers of cross-linked cellulose fibers. Recall that cellulose is a polymer of glucose monomer units. If you tear a piece of paper and look closely, you will see fine hairs sticking out.
These fine hairs are cellulose fibers. When paper products are recycled the cellulose furs are merely pulled apart and rearranged into new paper products. In some countries, paper recycling is highly encouraged by having specialized waste containers just for paper waste.
The paper waste is then collected and separated according to their properties. Sheets of paper are recycled with other sheets of paper and cardboard boxes are recycled with other cardboard boxes. Now, right before the paper can be recycled, any ink needs to be removed. This process is called de-inking.
Most inks are petroleum-based inks which are derived from crude oil products and can be difficult to remove. Currently in development are soy-based inks which are derived from a renewable resource and makes it easier for the paper to be de-inked. Metal parts such as staples and paper clips need to be removed with a magnet and glues are removed with a chemical wash. Bleach is sometimes added to whiten the slurry and therefore, the resulting paper product will be brighter.
The cellulose fibers in the slurry are mixed with new pulp and then allowed to settle on gauze and rolled to form the new sheets of paper. This step also removes any excess water from the slurry before it is air-dried. The main disadvantage with recycling paper is that it can only be done a few times.
Recycled paper is usually used to make kitchen rolls, toilet paper, and packaging materials. Each time a paper product is recycled the cellulose fibers become shorter thereby rendering the recycled paper product a little bit less useful than the original.
However, this can be used for another purpose. Can you remember what cellulase is? Hint: it is an enzyme. Please pause the lesson to think about this and resume when you are ready.
Cellulase is the enzyme that breaks cellulose apart into its glucose monomers. Currently, the industrial usage of cellulase is to break down cellulose into glucose. The glucose obtained can then be fermented by certain bacteria to produce ethanol, which can then be used as a biofuel.
In summary, recycling paper products help to reduce the rate of deforestation and consumes a lot less energy. Although paper can only be recycled a few times, the cellulose fibers can be broken apart into glucose monomers which can then be used for other environmentally friendly applications. Skip to main content. Recycling Polymers Print One way of classifying polymers is to break them up into two classes.
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