Mylar foil balloons can be inflated with a straw or a mylar balloon inflator if you are trying to inflate several. These inflators can save you a lot of time and effort and won't cost you much money. Mylar balloons are reusable, too, but you will have to deflate them first.
Manually Inflate a Mylar Balloon
You can blow up mylar balloons with air or helium, but if you want the balloons to rise, you must use helium. To blow one up with regular air, you will need a straw. First, locate the balloon's tail end and then insert a straw into the seal between the two plastic layers. The balloon's inner seal will open once the straw is in far enough.
Video of the Day
Pinch the sides of the straw (not too tightly) and blow into it. Take care not to over-inflate your balloon, or it will pop. When done, carefully remove your straw as you pinch the tabs together.
What's a Mylar Balloon Inflator?
A mylar balloon inflator is basically a helium tank with a special attachment, available to purchase or rent. If you choose to use this sort of tank, you should always store it in an indoor, well-ventilated area under 120 degrees Fahrenheit and free of any items that are combustible. Moist or outdoor areas should be avoided; exposure to excessive moisture can cause metal tanks to rust, leading to instability that may result in a burst tank. Be sure to keep the tank out of reach of children and pets, and don't place it in a heavily trafficked area or on the way towards an emergency exit. Never inhale helium, and always dispose of the tanks properly; many jurisdictions require special disposal at identified sites as opposed to mere recycling of the canisters.
Experts point out that you should not use a tank or attachment designed for latex balloons when you have mylar ones. Using the wrong inflator will damage (or even pop) the balloon. The latex balloon inflator tips are made from rubber, and the mylar ones are typically made from brass.
Find the opening in the balloon tail, and push the tank's nozzle on until it is airtight. Hold the balloon with one hand and press the nozzle with the other; this will pump in the helium. Once the balloon is inflated (do not over-inflate), gently remove the tail from the nozzle, keeping the tail pinched shut. Retaining your hold, stretch the balloon tail around your fingers and tie it in a tight knot.
Deflating Mylar Balloons
There are no machines that deflate mylar balloons. Instead, you will need to use a straw for each one, with each balloon only taking a couple of minutes. As when inflating them manually, use flexible straws instead of hard ones that could damage the balloons. Insert the straw into the balloon's tail's opening, gently pushing until you hear the air escaping.
Push on the balloon to speed things up and continue doing so until the balloon has completely flattened. Now, you can fold up it to get rid of any remaining air. Store the deflated balloons in zippered plastic bags in a dark location and re-inflate them later with a tank.
If you don't want to reuse your mylar balloons, be sure to recycle them. Because they use synthetic materials, tossing them into the trash or releasing them into the air is harmful for the environment. Instead, see if your town or county's curbside recycling programs will accept them. Another option is to seek a recycling center that can take them.