Observations
  • Home
  • Observations
  • Trendcasting
  • Odds 'n Ends
  • Science/Technology/Experiments
  • Mental Health

Silicone Foam from Silicone Caulk.

3/29/2020

33 Comments

 

Picture
Video Below:

Periodically I have a need for a good closed cell foam but not often enough to stock varying densities of different types of foam for occasional use. I have a preference for silicone foams as they have more physical qualities that allow some real latitude in use. But, I still did not want to buy the foam and decided to make it myself. I wanted to do it totally using simple chemistry and not get involved with CO2, O2, and nitrogen generation as foam producers. What followed was a number of experiments in thinning silicone caulk, and generating CO2 as the foam producer. Little did I realize how many roads of partial success and failure I was about to travel!
My overall goal was to produce a good, stable, and functional foam using materials that are already in our homes and readily available locally. This will be covered in the video and the best formula and procedure will follow the video. But I will start with the finished product so you can decide to watch my process or not. And, as always, comments and dialog are welcome. Enjoy the trip!
 
 

Standard Formula Materials:
Silicone caulk. Use GE type one, Dap, or other acetoxy cure silicone. The caulk has to cure with moisture liberating acetic acid. This is the one most used for sealing bathtubs and other areas. (Look for releases acetic acid on the back of the standard 10 ounce tube).
Silicone oil. Used for lubrication of many materials and readily available at hardware stores. I used Super Lube from Home Depot but any will work to thin silicone. (I learned the hard way to not use V M & P naphtha, Xylene, or others as they causes too many problems).
Surfactant. Any dish washing detergent to lower surface tension.
Baking Soda. Sodium Bicarbonate.
Vinegar. Regular white distilled vinegar.
Instructions:
Weigh out 20 grams caulk, 2 grams silicone oil, and 3-4 drops dish detergent. Stir well to integrate. These steps go together easily.
Add 10 grams baking soda. (Move quickly but mix completely to prevent voids. This will begin to skin over and release some acetic acid smell but this is normal).
Add 5 milliliters vinegar and continue to move quickly. (The mix will begin to foam but settles down fairly rapidly. You now have a stable closed cell silicone foam). It will cure externally in several minutes and cure completely in 12 hours. As most caulks perform, maximum strength is reached in 2-3 days.
 
33 Comments
Alan
4/5/2020 03:42:28 pm

Hi Ken, just wanted to thank you for the info and video, I can empty that box of old silicone tubes now and find a use for the foam.

Reply
Ken
4/6/2020 04:02:36 pm

Alan,
Sounds like a good plan and thanks, Ken.

Reply
Jeannie Llewellyn
4/6/2020 07:18:31 am

So, Ken, after mixing this together, that is the compound to use for sealing something we'd use caulk for? Or specifically, what is this used for? And would I only mix enough to use or can this be stored if sealed?

Reply
Ken
4/6/2020 04:09:58 pm

Jeannie,
This is standard sealing caulk and it cane be used anyway your imagination desires. I use it in so many projects like electrical standoffs and anytime I need a flexible material. Silicone has so many good qualities it can be fun to come with ideas for a springy material. Mix only enough to use as it sets fairly quickly and can't be stored. Thanks and good luck! Ken.

Reply
Philip Eddolls
4/6/2020 08:55:23 am

They Ken, thanks for sharing this. Super interesting.

Reply
Ken
4/6/2020 04:11:35 pm

Philip,
Glad that you enjoyed it and thanks for the comment. Ken.

Reply
Darlene Whitfield
4/7/2020 09:26:29 pm

Hi Ken,..My son sent me your video because I was planning on caulking my bathtub tomorrow and I was showing him the caulk and of course asking his opinion..now since i have two tubes to play with I know i will have a lot left over, If I dont end up with most of it all over me..So I am going to try your little experiment since i have all the ingredients except the kind of oil you have. Is there another oil that you know of that I could use? Its rather late right now so I will check back in with you tomorrow .and thanks so much I really enjoyed your video..

Reply
Ken
4/8/2020 03:03:43 pm

Darlene,
After a lot of experiments I found that there is no substitute for the silicone oil. However, it is available in all hardware stores and most craft stores like Michael's for making paintings with cell structure. Sorry but is should be easy to find. I got mine online at Home Depot. Ken.

Reply
Marcel link
4/12/2020 05:45:49 pm

Hi Ken. Thanks a lot for sharing this.

It's a long shot but we might have a use for this on respirator masks which are being 3D printed to help in the fight against Covid-19. It would be a much better solution than self-adhesive foam strip.

The challenge now is to see if we can 'pipe' it around the face-edge!

Would there be any gains to be had in mixing say the bicarb with the silicone oil first? Maybe with the surfactant also?

Best wishes

Marcel

Reply
Ken
4/13/2020 03:22:07 pm

Marcel,
You can mix the materials in any way you want as long as the vinegar is last. But, I see no advantage mixing the baking soda especially since there is such a small amount of oil. Good luck and thanks, Ken.

Reply
Marcel
4/13/2020 03:30:52 pm

Cheers Ken. Game on!

Mark
5/15/2020 01:12:56 pm

https://www.youtube.com/watch?v=8kM8IGONYCM&t=6s

Hi Ken, Great video as always. The latest foam "craze" is Foam Mo or Cosplay Foam. Attached video above. Any idea how to go about making this? Hoping you could send me in the right direction with some ingredients in which to experiment. Thanks in advance.

Reply
Dawn
7/1/2020 09:15:57 am

Hi Ken,

I read an article that used gas bubbles in conjunction with a sugar cube template for sugar leaching. Do you think that it would be possible to use sugar leaching with your method? I want to create an open foam system so it will be more like a sponge. I am really limited now on what I can order because the lab is closed.

Thank you,

Dawn.

Reply
Ken
7/1/2020 09:42:34 am

Dawn,
Because of the very low surface energy of silicone, leaching is not possible. It is more likely to be successful with cellulose. But, that will take some research, Ken.

Reply
GEO sustainable link
8/14/2020 01:41:38 am

I am the one that invented this process, and posted the video showing the process on 14 Feb 2020. I would appreciate an acknowledgement of this fact.

Reply
Ken
8/14/2020 08:44:42 am

GEO sustainable,
These are two totally different methods of making foam from silicone caulk. Not only are the materials dissimilar, mine is a chemically based reaction and really expands significantly. Mine sets within 10 minutes and is truly a foam. Let's not compare apples and oranges. Your method is interesting but no where near my attempt to make a closed-cell foam. Congrats on an innovative process. Ken.


Reply
Christopher
9/21/2020 10:05:28 am

Another "inventor" who "invented" something. You are better off file a patent and do patent scam. Methods and discoveries CANNOT be invented.

Reply
Christopher
9/21/2020 10:24:18 am

There are BIG factories and corporations in China are also making silicone foam. It is a common practice in the cosmetic industry to use silicone oil of one to dilute another thicker silicone oil.

Why do you not go to them and say "Hey, how dare you do not acknowledge me, the inventor of the method and discoverer of silicone oil that you copied and plagiarized"?

Reply
GEOsustainable link
8/15/2020 06:03:04 am

Curious how I discover silicone oil, and a month later you use it, without acknowledging the inventor.

Reply
Ken
8/15/2020 10:09:40 am

GEO,
I have been using silicone oil for over 30 years as a lubricant and diluent and it is not curious at all why I used it as naphtha is a terrible diluent. I have never copied other's without acknowledgement and never will.

Reply
Christopher
9/21/2020 10:09:21 am

You post your video before others does not mean you invented anything. You are doing a business and therefore you there hunting for victims and you hope that your threat works on them.

Ken is an old man and he is not into business, hence why he could "invent" something and post the video only when he is in six feet under if he wishes.

Reply
Ken
9/21/2020 04:27:04 pm

Christopher,
Clearly spam and troll. Say goodby!

GEOsustainable link
9/22/2020 04:26:36 pm

I must agree with your first point. I was just tinkering and fell over this, I shared it outright and therefore free to use by anyone. And, perhaps inventor was a bit of a stretch, I get in the groove sometimes as that is what I get paid to do. Methods and discoveries are most certainly patentable, most patents start with such words. Still, thanks for taking me down a notch.

Reply
Ken
9/22/2020 05:05:57 pm

GEO,
Great dialog and thanks for the comment. My site is open source and can be used by anyone with attribution. Unfortunately I don't get paid but do it for the learning aspect. I follow your channel and it is always interesting. This email exchange is the way we should all act-Like decent caring people! Ken.

Reply
Helena Parriott
10/17/2020 04:44:01 pm

Greetings! this is just wonderful. I appreciate your exploration on this.
How many times does the mass of silicone expand, from one tube, for example? Have you measured that before?

Reply
Ken
10/20/2020 09:59:20 am

Helena,
The volume increase for the current formula is about 5 times and I haven't tried the volume of a tube. But this formula is a starting point and can probably be better optimized, Ken.

Reply
Ondrej Mikeska
4/16/2021 11:56:50 am

Good evening sir,
just wanted to thank you for sharing your knowledge, amazing.

Greetings from Czech Republic

Reply
Mike
8/23/2021 05:17:01 am

Hi, great video.
Do you use the acetic acid primarily as an accelerator? Would it foam even without it or would the competing decomposition of the sodium bicarbonate make the curing rate too slow and the co2 generated would slowly leak. A bit like opening a bottle of soda quickly vs slowly

Reply
Brian
9/7/2021 11:08:40 am

So from my understanding the acetic acid is a product of the curing reaction, not a part of it. This means that it's only produced once some of the silicone curing reaction has occurred. So the issue is that the foaming process of the sodium bicarb is dependent on the curing process completing first to produce the acetic acid. This causes a sort of race condition between the two reactions. You need the foaming reaction to produce bubbles before the silicone curing reaction is complete throughout the silicone, or you'll have a much denser foam with (speculation) possibly thicker cell walls. So yes, I imagine the extra acetic acid is added to accelerate the foaming reaction so the curing reaction doesn't outpace it.

Reply
Ryan b.
2/1/2022 12:49:38 pm

Hi Ken I just found this formula/recipe and I’m so very interested in it. I had a few questions in case you have already come across these before I do R&D first one is what is the expansion rate or calumet increase from raw materials to final product? Two is it conductive or have you tried making the foam conductive? How refined are the celis? Had you had any success with any newer formulas or recipes if so could I try those? Have you tried yeast I know it’s a buzzard question and if so did you have any success? Do you have any info on the degradation or decomp of the cell structure over time or under stressors? I’m interested in expanding on this idea a
Be recope and I will give all credit to you and your original formula. Any advancements or new ideas or additions I will credit towards myself if that is acceptable?

Reply
anna
4/21/2022 08:34:46 am

so i have a somewhat stupid question... is vinegar actually necessary here? could the same amount of water do the trick? the reason i ask is, there should already be a ton of acetic acid in the type1 silicone to react with the baking soda - as i accidentally found out while trying to make some oomoo indoors (big mistake: my eyes and nose were burning seconds after i squeezed out a bunch of caulk!) given the fairly low concentration of the acetic acid in grocery store distilled vinegar, my immediate uneducated guess would be that the caulk should have plenty more of it available immediately, to react with the baking soda even before the silicone curing is well under way. i guess adding vinegar vs water doesn't make a lick of difference (the vinegar is cheap and widely available, and you are already stinking the place up with the caulk, so a little vinegar hardly makes a difference there), i'm just curious if you tried that (and reluctant to stink up my studio this morning by trying it out myself)

Reply
Eevee
8/1/2022 02:03:36 am

I am curious if adding rubbing alcohol would help the drying process, and if so, if it would make the foam more brittle.

Reply
Thomas King link
11/11/2022 03:17:16 pm

I love the concept and the process! I was thinking of doing something similar, and you have saved me from all that pesky repetitive trial and error. Most people see the answer, shrug, and have no appreciation for the lengthy sequence of failed attepts that lead there. Bravo! Well done! Thanks for sharing!

Reply



Leave a Reply.

    Author

    The author has an eclectic background in chemistry, electronics, writing, mental health, and community action...Ken

    Archives

    June 2021
    March 2020
    September 2019
    August 2018
    August 2017
    March 2017
    December 2016
    November 2016
    October 2016
    August 2016
    April 2016
    December 2015
    September 2015
    May 2015
    March 2015
    February 2015
    December 2014
    November 2014
    October 2014
    September 2014
    August 2014
    July 2014
    June 2014
    May 2014
    April 2014
    March 2014
    February 2014
    December 2013
    November 2013
    October 2013
    August 2013
    July 2013
    June 2013
    May 2013
    April 2013
    March 2013
    February 2013
    January 2013
    December 2012
    November 2012
    October 2012
    September 2012
    August 2012
    July 2012
    June 2012
    May 2012
    April 2012
    March 2012
    February 2012
    January 2012
    December 2011
    November 2011
    October 2011
    September 2011
    August 2011
    July 2011
    June 2011
    May 2011

    RSS Feed

    Categories

    All
    Acid And Bases
    Amateur Scientist
    Anodizing Aluminum
    Anthocyanin Indicator
    Ant Orientation
    Artificial Intelligence
    Bar And Cr Code
    Cable Tie
    Carbon Dioxide Fun
    Catalase And H2o2
    Chemical Art
    Cold Cathode
    Color Hot Glue Sticks
    Common Chemicals
    Copper Plating
    Cyanotype/Blueprint
    Dot Com
    Electroluminescence
    Epoxy Art
    Experiments
    Hydrogels
    Infrared Photography Basics
    Magnetic Money
    Old Textbooks
    Photograms
    Science
    Static Electricity Detector
    Technology
    Yogurt