×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Safe Expanding Foam

Safe Expanding Foam

Safe Expanding Foam

(OP)
Hi,

I came across this forum and figured it'd be the best placed to post my question.  I've got an idea for a product - the main component of this product is a piece of foam which can expand to the size of approximately an envelope but about a half inch high (lets say there will be a textual material or plastic container acting as a mold to help shape the expanding foam). The foam needs to be non-toxic, and slightly pliable (applying pressue - pushing your thumb to it would leave a slight indent that return to it's original state, and the entire envelope sized piece of foam would have a little give to it allowed it to bend lengthwise).  

Prior to the foam expanding, it needs to be within a container no bigger than half a bar of soap, or half the size of one of those mini-tissue packs.

The chemicals that create this foam need to be stored in such a way that a cracking motion (think glow stick) or shaking motion (I'll need to ultimately decide on the best method) will cause the chemical reaction to make the foam expand.   

The idea will only work successfully if the foam can expand by simply mixing two (or more)chemicals together, without dispensing via a pressurized can.

Does anyone know if such a type of foam exists?

Thank you.
Matt
meltznyc-dn@yahoo.com

RE: Safe Expanding Foam

The urethane foams used in packaging are 2-component. The 2 substances are mixed whe injected into the box, and then the foam expands to fill the container. Urethane is nontoxic unless burned-the combustion products are nasty.
Your trick would be to package a "shot" of the components to mix and expand when required.  One other consideration: Urethane foam is really sticky until it cures.

RE: Safe Expanding Foam

Though the cured foam may be considered non-toxic, the isocyanate reagents used to make urethane foams are quite far from non-toxic!

RE: Safe Expanding Foam

Some comments/options

1.Eliminate the chemicals
Cut some type of resilient foam to the finished product dimensions - then squish it into your "bar of soak" container - might need to use some pneumatic pressure device but it could be done.
Now if the finished product had an airtight surface and a vacuum was drawn on the internal volume . . ..  Permanent foam deformation might be a problem . . Maybe some "music wire" internals to reshape the foam.

2. A singular container
Allow the "thick walled" original container to expand (by some "unfolding" idea)into the final shape. Then allow the mold to be opened via a soda drink pull tab (or draw string)mold perimeter cutting device.

RE: Safe Expanding Foam

Banks around here used to pass out things that looked like thick brown business cards, with their logo printed on them.

When you got them wet, they expanded just as you desire.  

Dried compressed sponges.



Mike Halloran
Pembroke Pines, FL, USA

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources