Plastic

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Plastic is a material consisting of any of a wide range of synthetic or semi-synthetic organic compounds that are malleable and so can be molded into solid objects. They are typically organic polymers of high molecular mass and often contain other elements.

Plasticity is the general property of all materials which can deform irreversibly without breaking but, in the class of moldable polymers, this occurs to such a degree that their actual name derives from this specific ability.

General

Plastics are usually classified by the chemical structure of the polymer's backbone and side chains; some important groups in these classifications are: the acrylics, polyesters, silicones, polyurethanes, and halogenated plastics.

Plastics can also be classified by: the chemical process used in their synthesis, such as: condensation, polyaddition, and cross-linking.

Types of plastic

This category includes both commodity plastics, or standard plastics, and engineering plastics.

  • Polyamides (PA) or (nylons) – fibers, toothbrush bristles, tubing, fishing line and low-strength machine parts such as engine parts or gun frames
  • Polycarbonate (PC) – compact discs, eyeglasses, riot shields, security windows, traffic lights and lenses
  • Polyester (PES) – fibers and textiles
  • Polyethylene (PE) – a wide range of inexpensive uses including supermarket bags and plastic bottles
    • High-density polyethylene (HDPE) – detergent bottles, milk jugs and molded plastic cases
    • Low-density polyethylene (LDPE) – outdoor furniture, siding, floor tiles, shower curtains and clamshell packaging
    • Polyethylene terephthalate (PET) – carbonated drinks bottles, peanut butter jars, plastic film and microwavable packaging
  • Polypropylene (PP) – bottle caps, drinking straws, yogurt containers, appliances, car fenders (bumpers) and plastic pressure pipe systems
  • Polystyrene (PS) – foam peanuts, food containers, plastic tableware, disposable cups, plates, cutlery, compact-disc (CD) and cassette boxes
    • High impact polystyrene (HIPS) – refrigerator liners, food packaging and vending cups
  • Polyurethanes (PU) – cushioning foams, thermal insulation foams, surface coatings and printing rollers: currently the sixth or seventh most commonly-used plastic, for instance the most commonly used plastic in cars
  • Polyvinyl chloride (PVC) – plumbing pipes and guttering, electrical wire/cable insulation, shower curtains, window frames and flooring
  • Polyvinylidene chloride (PVDC) – food packaging, such as: Saran
  • Acrylonitrile butadiene styrene (ABS) – electronic equipment cases (e.g. computer monitors, printers, keyboards) and drainage pipe
    • Polycarbonate/Acrylonitrile Butadiene Styrene (PC/ABS) – a blend of PC and ABS that creates a stronger plastic used in car interior and exterior parts, and mobile phone bodies
    • Polyethylene/Acrylonitrile Butadiene Styrene (PE/ABS) – a slippery blend of PE and ABS used in low-duty dry bearings

Uses

Plastic is a common lab item, due to its chemical resistance of some types, low density, good strength.

Burning plastic droplets falling on the ground will cause an interesting sound effect, which is caused by the movement of the burning flame falling through air.[1]

References

  1. https://www.youtube.com/watch?v=Q7b-yabEa7g

Relevant Sciencemadness threads