You’ve probably seen Mylar in shiny helium balloons, space blankets and protective plastic coatings. It is actually a brand name for clear, thin polyester film.

Mylar is also known as BOPET (biaxially-oriented polyethylene terephthalate). It has high tensile strength, chemical stability and resistance to ionizing radiation.

Mylar can be metalized with a very thin layer of aluminum, making it even more useful. Aluminized Mylar film is a good choice for many applications.


It can be made to look matte or shiny and is used for things like food packaging, kites and survival blankets. It is also an excellent thermal insulator and has good resistance to chemicals and oils.

Mylar is a very good reflector of infrared radiation and can be made to be even more reflective by being aluminized. This type of mylar is often used in space blankets to help prevent heat loss from the body.

Aluminized mylar is a metallicized PET film that has an aluminum layer applied under high vacuum conditions. It combines the reflective mirror aluminum metallic luster of metal foil with the transparency and gas barrier properties of polyester.
Thermal Insulation

When multiple layers of aluminized Mylar are placed together in a blanket, the material offers excellent thermal insulation. Mylar reflects infrared radiation, which helps to keep heat from heating objects in close proximity. This is especially useful in space, where solar radiation can quickly warm things up.

Mylar is also an effective barrier against fluids, such as air. It will block convection and advection, but it will allow conduction to pass through.

Foil is not as good at this, but mylar has the advantage that it can be bonded with objects easily. This is an important feature, as it can expand the life of food storage bags such as retort pouches or vacuum bags.
Gas Barrier

Mylar is a brand name of the biaxially-oriented polyethylene terephthalate (BOPET) plastic film which is famous for its high tensile strength, chemical and dimensional stability, transparency, reflectivity, and gas barrier properties. It is often used for packaging foods, and it can also be used as an electrical insulation material.

Mylar can be made into metallised films, which are coated with a layer of metal. These films have the glossy metallic appearance of aluminium foil, but are much lighter and cheaper. They are sometimes used for decorative purposes, such as gift wrappers or ribbons. They are also used for novelty items, such as the metallic helium-filled balloons given away at Christmas.

Moreover, the metal-aluminium barrier of Mylar reduces oxygen and moisture penetration into the packaging. This significantly increases the shelf-life of packaged food.
Chemical Resistance

Mylar can withstand extreme heat and humidity, which makes it ideal for protecting fragile items or preserving foods. It can also be used to create lids that prevent moisture and contamination, while keeping foods fresher for longer.

Mylar is chemically unreactive, making it safe to use in a wide variety of environments. It is also impermeable to gasses, allowing it to prevent odors and keep products sealed in for as long as possible. This makes it a top choice for nameplates that require durable protection against oil and other liquids.
Easy to Clean

When you think of Mylar, you likely associate it with the shiny, silvery balloons used in birthday parties and other celebrations. While those are actually made of foil, Mylar is a brand name for a specific type of transparent polyester film that can be coated with an extremely thin layer of aluminum metal or other materials to improve its properties.

Mylar can be found in food packaging, musical instruments and even kites. It can also be machine embroidered with metallic thread to create beautiful and eye-catching designs.

Mylar is a useful material for growers, improving plant growth by using its reflective surface to amplify lighting. It can withstand high temperatures and is easy to clean. It reflects approximately 85% of radiant heat energy, so proper ventilation is needed when using it in your grow room to prevent hotspots.