plasticity

Examples of plasticity in the following topics:

• The Age of Plastics

  • Many modern adhesives involve the formation of a plastic bonding substance.
  • Plastics have replaced an increasing number of natural substances.
  • In the manufacture of piano keys and billiard balls plastics have replaced ivory, assisting the survival of the elephant.
  • With all these advantages it is not surprising that much of what you see around you is plastic.
  • Indeed, many plastics are employed in disposable products meant only for a single use.

• The complexities of recycling

  • PET plastics are commonly used to make food and drink containers.
  • When recycled, HDPE plastics are reduced to landfill liners, fencing material, flower pots, plastic lumber, recycling bins, buckets, oil containers and benches.
  • The seventh category of plastic includes plastics that do not fall into the previous six categories.
  • One example is malamine, a plastic used to make plastic cups and plates.
  • When recycled, category-seven plastics can be used to make plastic lumber and plastic bottles.

• Recycling and Disposal

  • Most plastics crumble into ever-tinier fragments as they are exposed to sunlight and the elements.
  • Thus, instead of consigning all plastic trash to a land fill, some of it may provide energy by direct combustion, and some converted for reuse as a substitute for virgin plastics.
  • Whether used as fuels or a source of recycled plastic, plastic waste must be separated into different categories.
  • Despite use of the recycling symbol in the coding of plastics, there is consumer confusion about which plastics are readily recyclable.
  • (Los Angeles, for example, recycles all clean plastics numbered 1 through 7) In theory, most plastics are recyclable and some types can be used in combination with others.

• Recycling

  • Cascade Engineering, a Grand Rapids, Michigan, plastics manufacturer that makes parts for cars and various plastic containers – including trash cans –has cut the amount of trash it sends to landfills from 2,475 tons in 2003 to just over 700 tons this year.
  • Virtually anything from building materials to metals to chemicals to paper to plastic to fabrics or food and cloth – and, in some cases, unused medicine – can be recycled.
  • Recycling a plastic bottle saves enough energy to power a 60 watt light bulb for three hours.
  • 25–30 plastic 1 litre plastic bottles can be recycled into one fleece jacket.

• The Law of Unintended Consequences

  • The larger North Pacific Subtropical Gyre, referred to as the doldrums, is the convergence zone where plastic and other waste mixes together.
  • No one knows how long it will take for some of these plastics to biodegrade, or return to their component molecules.
  • Smaller plastic scraps are mistaken for food by sea birds; and are often found undigested in the gut of dead birds.
  • Nurdles, lentil-size pellets of plastic, found in abundance where plastics are manufactured and distributed, are dispersed by wind throughout the biosphere.
  • Escaped nurdles and other plastic litter migrate to the ocean gyre largely from land.

• Synaptic Plasticity

  • Synaptic plasticity is the strengthening or weakening of synapses over time in response to increases or decreases in their activity.
  • Plastic change also results from the alteration of the number of receptors located on a synapse.
  • Synaptic plasticity is the basis of learning and memory, enabling a flexible, functioning nervous system.
  • Synaptic plasticity can be either short-term (synaptic enhancement or synaptic depression) or long-term.
  • Short-term synaptic plasticity acts on a timescale of tens of milliseconds to a few minutes.

• Rhinoplasty

  • Rhinoplasty, a nose job, is a plastic surgery procedure for correcting and reconstructing the form of the nose.
  • Rhinoplasty, a nose job, is a plastic surgery procedure for correcting and reconstructing the form, restoring the functions, and aesthetically enhancing the nose by resolving nasal trauma (blunt, penetrating, blast), congenital defect, respiratory impediment, and a failed primary rhinoplasty.
  • The plastic surgical correction of congenital and acquired abnormalities of the nose restores functional and aesthetic properties by the surgeon's manipulations of the nasal skin, the subcutaneous (underlying) cartilage-and-bone support framework, and the mucous membrane lining.
  • Technically, the plastic surgeon's incisional approach classifies the nasal surgery either as an open rhinoplasty or as a closed rhinoplasty procedure.
  • The open rhinoplasty approach in turn affords the plastic surgeon the advantages of ease in securing the grafts (skin, cartilage, bone) and, most important, in seeing the nasal cartilages proper, and so make the appropriate diagnosis.

• Recycling and industrial waste

  • In India, for example, discarded plastic bottles and bags are being shredded, melted and added to roadway asphalt to improve the integrity, water resistance and durability of paved roads.
  • Apparently, roads embedded with melted plastic last three times longer than conventional roads (although keep in mind that the environmental impact of this practice is unknown).

• Withdrawing Blood

  • A blood collection tube is a sterile glass or plastic tube with a closure.
  • The vein is first punctured with the hypodermic needle which is carried in a translucent plastic holder.
  • The test tubes are covered with a color-coded plastic cap .
  • They often include additives that mix with the blood when collected, and the color of the tube's plastic cap indicates which additives that tube contains.
  • The plastic caps are opaque for tubes with a normal vacuum.

• Types of Synthetic Organic Polymers

  • Despite competition from more modern polymers, LDPE continues to be an important plastic grade.
  • Polyvinyl Chloride (PVC) is the third-most widely produced plastic, after polyethylene and polypropylene.
  • It can be made softer and more flexible by adding plasticizers, the most popular of which are phthalates.
  • One of the most popular plastics, PS is a colorless solid that is used, for example, in disposable cutlery, plastic models, CD and DVD cases, and smoke detector housings.
  • Thermoplastic polyurethane (TPU) is any of a class of polyurethane plastic.