A balloon is a flexible membrane bag that can be inflated with a gas, such as helium, hydrogen, nitrous oxide, oxygen, or air.
For special purposes, balloons can be filled with smoke, liquid water, granular media (e.g. sand, flour or rice), or light sources.
Modern day balloons are made from materials such as rubber, latex, polychloroprene, or a nylon fabric, and can come in many different colors.
[1][2] Balloons are used for decorating birthday parties, weddings, corporate functions, school events, and for other festive gatherings.
Party balloons are mostly made of a natural latex tapped from rubber trees, and can be filled with air, helium, water, or any other suitable liquid or gas.
Filling the balloon with air can be done with the mouth, a manual or electric inflater (such as a hand pump), or with a source of compressed gas.
When rubber or plastic balloons are filled with helium so that they float, they typically retain their buoyancy for only a day or so, sometimes longer.
The inside of balloons can be treated with a special gel (for instance, the polymer solution sold under the "Hi Float" brand) which coats the inside of the balloon to reduce the helium leakage, thus increasing float time to a week or longer.
[4] Beginning in the late 1970s, some more expensive (and longer-lasting) foil balloons made of thin, unstretchable, less permeable metallised films such as Mylar (BoPET) started being produced.
These balloons have attractive shiny reflective surfaces and are often printed with color pictures and patterns for gifts and parties.
The most important attributes of metallised nylon for balloons are its light weight, increasing buoyancy, and its ability to keep the helium gas from escaping for several weeks.
Usually the round shape of the balloon restricts these to simple arches or walls, but on occasion more ambitious "sculptures" have been attempted.
This ensures that the helium-filled balloons do not float into the atmosphere, which is potentially injurious to animals, the environment, and power lines.
Custom built printers inflate the balloon and apply ink with elastic qualities through a silk screen template.
In January 2008, the Jewish Community Relations Council of New York organized a display of 4,200 red balloons outside the United Nations Headquarters.
Once in place, the balloon is inflated to clear or compress arterial plaque, and to stretch the walls of the vessel, thus preventing myocardial infarction.
A small stent can be inserted at the angioplasty site to keep the vessel open after the balloon's removal.
[13] Insertion of balloons subsequently filled with air or liquid can be used to stop bleeding in hollow internal organs such as stomach or uterus.
By the 18th century, people were inflating balloons of cloth or canvas with hot air and sending it aloft, the Montgolfier brothers going so far as to experiment with first animals in 1782, and then, when altitude did not kill them, human beings in 1783.
By 1825 similar balloons were being sold by Thomas Hancock, but like Faraday's they came disassembled, as two circles of soft rubber.
The user was expected to lay the circles one on top of the other and rub their edges until the soft, gummy rubber stuck, leaving the powdered inner part loose for inflation.
[15] Released balloons can land anywhere, including on nature reserves or other areas where they can pose a hazard to animals through ingestion or entanglement.
Because of the potential harm to wildlife and the effect of litter on the environment, some jurisdictions even legislate to control mass balloon releases.
Legislation proposed in Maryland, US, was named after Inky, a pygmy sperm whale who needed six operations after swallowing debris, the largest piece of which was a Mylar balloon.
[20][21] This issue can have an effect on the wildlife on both land and in aquatic systems because animals will confuse deflated balloons as food, nesting material, or simply something to play with.
These balloons manufacturing processes preserve the natural state of the material in such a way that allows it to degrade relatively quickly.
[27] Some of the manufacturers only use rubber trees that are grown in plantations that receive the Rainforest Alliance's approval, and at which its representatives conduct regular inspections in order to make sure that the farmers meet several criteria set to ascertain that the biological diversity in the area is maintained, and that no worker or natural resource is abused in the material manufacturing process.