Making a super insulated silicone bottle

[Anonymous]

I have a hyrdoflask vacuum insulated bottle, and it’s nice, but it’s heavy being made out of stainless steel. I can’t afford a titanium vacuum insulated bottle (and they’re still on the heavyish side), so i’ve been thinking of ways to make an alternative that may be even lighter.  I don’t have the capabilities for vacuum insulation unfortunately, but in any case, while nothing can beat vacuum insulation–it always has a weakness, the top, not well insulated part.

There are two main ideas, one is more expensive and complex, and the other easier and cheaper.  Feel free to vote.

Both ideas center around using a silicone bottle for the part that will hold water.  Silicone because it’s fairly lightweight, relatively inexpensive, fairly low thermally conductive, probably the least reactive and most inert of the plastics commonly being used for food/beverage products, and it handles heat very well (and boiling water no problem).   Also, when not being used, in one of the iterations below, it can be squashed down to conserve space if need be.  Initially i was looking at Al bottles, but it seems they all have some kind of either epoxy or resin liner, which probably has chemicals with estrogenic type effects.  I wanted to get a plain old brushed Al bottle and anodize it myself, but it’s surprisingly hard to fine pure Al bottles.  In any case, the silicone bottle seems better all around for this purpose.

1st, the more expensive and complex concept:  Buy a larger PP (polypropylene #5), cheap, wide mouth bottle–into same will go the silicone bottle, as well as insulation and Al foil.  First build a cozy out of bumpy foam, smooth side will wrap around the silicone bottle w/ a bit of space.  Around the bumpy part, i will wrap some heavy duty Al foil or heat sheet material.  Into the various spaces between the two bottles will go hydrophobic silica aerogel particles (roughly 1 mm in size), which i can buy 4 cups of for 45 dollars and for the amount i use, won’t register on my scale by itself.  The silicone bottle will fit through the lid of the PP bottle (cut a hole), and i will seal it up with an epoxy, hot glue or what not.

Then make a top, simple “sleeve” to go over the top of both bottles, out of a combo of silpoly membrane and breathable .66 oz/yd2 membrane and stuff with some left over 600 fp down i have.  The silpoly will go on the inside to block moisture, the .66 oz nylon will be on the outside to let the Down breathe and loft.  Since it will be a simple sleeve, and won’t have enough insulation at the seams at the very top, so into the sleeve i will stuff some left over Apex (probably with some fabric sewn around it to protect it some).

I figure the above will have some pretty serious insulating capacity at not much weight.  The silicone bottle is a 20 oz one, and i’m estimating it (the total system) to weigh total around 7 to 9 oz dry. That’s about the same weight as a non insulated, single wall SS bottle of similar size.

Ok, the more simple and less expensive version:  Basically just make the foam cozy that goes up most of the way of the bottle, wrap with Al foil or heat sheet, and make two separate sleeves using the above fabrics mentioned and the Down.  One goes over the bottom and the foam cozy and the other, thicker and wider, goes over the top (again with Apex pushed into the top).  This version won’t cost me any extra money besides the silicone bottle i’m waiting on, is easier, and more convenient to clean, and will take up less space in the pack.  Also probably will be a bit lighter since it’s sans the PP bottle.

WWBPLD?  And thermally speaking, do you think either version can compete with a traditional vacuum insulated bottle for keeping water warm?   I suspect concept 1 will have the thermal edge due to the aerogel material, which is the next best thing to vacuum insulation weight and thermally wise.  But do i want to spent 45 dollars on 4 cups of this stuff… not so sure.  Perhaps if someone was interested in buying the same kind of bottle insulation system off me for around 25 dollars, i’d might consider it.  (I’m actually receiving two 20 oz silicone bottles at the same time anyways).

[DancingBear]

Interesting.  I have a question for option #1 though – why not put the bumpy side of the foam toward the bottle to create air pockets?

Also an observation: my wife made some bottle sleeves out of silnylon and Insulbrite, and one thing we found out immediately is that we needed a means to stiffen the top of the sleeve so it didn’t collapse and make it difficult to insert the bottle.  We settled on long cable ties, but weed-eater line or the stiff plastic banding you see around cases of printer paper would probably work too.

 

[Jerry Adams]

1 square foot of that bubble wrap with foil stuff weighs 0.8 ounces.  Wrap a re-used PET water bottle with it.  Maybe 1 square foot would be enough.

[Cayenne Redmonk]

If you adopted Rogers huge foam block pillow, you could put bottles in the holes.

[Valerie E]

Why not just use whatever bottle you want, and keep it in an OR Water Bottle Jacket?  Worked perfectly for me when snowshoeing in winter in Upstate NY and VT… relatively cheap and easy.

[Anonymous]

“I have a question for option #1 though – why not put the bumpy side of the foam toward the bottle to create air pockets?”

  Hi Dancing Bear, the reason is because IR reflective materials apparently need some air space on both sides in order to reflect IR radiation. If the foam was directly touching most of the Al foil or heat sheet material, it wouldn’t be able to reflect the IR, and then also the metal (highly conductive) would begin to conduct heat away more so.

Thank you for the tip.

[Anonymous]

“1 square foot of that bubble wrap with foil stuff weighs 0.8 ounces.  Wrap a re-used PET water bottle with it.  Maybe 1 square foot would be enough.”

I think that would work “ok”, but there are some issues for me with the above.  One, that bubble wrap is essentially throw away material (something i’m trying to get away from). Also, i don’t want to be in extreme cold temp conditions and potentially have some bubbles pop or even have to worry about it.

Two, PET bottles can be used without much leaching for a few times or so, under more normal conditions.  Put boiling water in it, and you really speed up the process.  My man boobs are big enough without help, thanks.  (J/K)  The insulated bottle will be primarily for boiling water to be used down to potentially extreme temps (negative *F if they occur like they did last year and the year before).  I rarely ever purchase bottled water, etc, so i wouldn’t have a steady supply of replacement.

Besides, the insulation provided by Down or Aerogel would be much, much more efficient than the reflectix.  In Down’s case, also much more packable, and if i go with the 2nd concept, the whole thing would be very packable minus the foam cozy.

[Jerry Adams]

Oh – boiling water – I wouldn’t use plastic either

[Anonymous]

“If you adopted Rogers huge foam block pillow, you could put bottles in the holes.”

 Not familiar with said pillow, but in any case, doesn’t sound very mobile or convenient.  Are you channeling B.G. btw?

[Anonymous]

“Why not just use whatever bottle you want, and keep it in an OR Water Bottle Jacket?  Worked perfectly for me when snowshoeing in winter in Upstate NY and VT… relatively cheap and easy.”

I’m trying to recreate the near insulation potential of a vacuum flask.  The OR Water bottle jacket is just a little bit of open celled foam and a little fabric–it won’t come anywhere close.  The good thing about the OR bottle parka is, is that unlike vacuum flasks, they are insulating the top, which helps to close the efficiency gap a little (vacuum flasks/thermos’s lose all their heat via the top).  I’m trying to create a bottle that i could put boiling water in at night time before bed and have warm to hot’ish water in the morning when i wake up, even with sleeping out in below 0 temps F.

Also, if i go with the 2nd concept–minus the silicone bottle, it won’t cost me anything (i have extra of all the materials already from past projects etc) and would actually be a pretty quick and easy project (since the Down will be in a small space and over stuffed, won’t need any baffles).

Whereas the OR piece retails for 30, not including shipping, and considering the materials involved probably cost a total of a dollar or less for them total, a bit on the expensive side for what it is.  A bit of cheap foam with a fabric covering.

On the other hand, if i go with the 1st concept, while a bit more expensive at the outset than the OR piece, using Aerogel (especially) plus foam plus Down would be many, many, many times more efficient than the insulation provided by the OR piece.  I would probably have enough Aerogel left over for making at least one more insulated bottle system (which if nobody from BPL is interested in buying it, i would give to my spouse).

 

[Anonymous]

So i’ve decided for now that i’m going to go with the 2nd concept to save time and money.  Since i’ll have a 2nd silicone bottle, if the in the future i have some excess spending money, i’ll purchase the Aerogel particles and make the 1st system. (Perhaps i should start a Kickstarter to fund same…hahaha).

But dang, just imagine how cool the 1st concept bottle insulation system would look?  “Oh, that, that’s just my ‘frozen smoke’ blue, translucent water bottle cozy.  I don’t often drink hot water out of a silicone bottle, but when i do, it’s out of this cozy.” (course said with a slight Hispanic accent…)

So when i’m really bored on a winter trip with it’s short days, at night, i can shine flashlights, fire light, etc at my bottle insulation system and keep myself entertained for hours until it’s (FINALLY!!!) a reasonable time to go to bed.  Move over log, there’s a new toy in town and it’s much more wunderbar by far.

(note to my BPL connected self, don’t post while overly tired, it’s almost as bad as posting drunk)

[Anonymous]

Finished the project latish last night.  I’m getting ready for a 2 day weekend trip, so i will post pics sometime on Monday.  But weights for now.  22 oz Silicone bottle weighs 3.1 oz, foam cozy plus Al foil weighs 1.6 oz and RBTR Membrane Silpoly/.66 oz/yd2 nylon membrane Down sleeve plus some Apex, some 1/8 foam, and Al foil weighs 4 oz, for a total of 8.7 oz.  Last night, i put boiling water inside the bottle and put it in the fridge at 11:20 pm.  I’m going to check it at 11:20 am and see what the temp is like.  Didn’t have space in the freezer.

I’m thinking that i can improve the Down sleeve–right now, it’s basically the size and shape of a small down pillow with an opening.   Because i sewed it like a pillow, there isn’t much Down insulation at the top where it needs to be the most, and so i stuffed the inside with a combo of Apex, Al foil (in between two layers of Apex) and a little 1/8 Evazote foam.  In hindsight, not very bright.

Looking at it, it would make an awesome pillow, especially since i can stuff a shirt or something in the middle.

So i’m going to make a smaller, and more efficiently designed sleeve with most of the Down at the top and less at the sides, since the foam cozy part should be pretty insulating on the side anyways.  Since it would be smaller, have less down, much less Apex (i would still use some to put the Al foil in between), and no foam, i can probably cut the weight by 1 oz to 1.5 oz, getting the whole system down to 7.7 oz to 7.2 oz or so, which for a very well insulated system is not bad at all.

Stay thirsty my friends.

[Anonymous]

Just checked the temp, felt luke warm to the touch, so about skin temp (90 degrees or so?). Couldn’t find my thermometer, but for later tests will use one.

I was hoping for it to be warmer, but 12 hours in a fridge and still being warm’ish is not bad, considering that i would put it in the quilt with me when sleeping, or when hiking near my back when in the pack, both which can keep it above fridge temp in most conditions.

It’s actually about on par with some vacuum insulated bottles that i’ve had.

[Cayenne Redmonk]

http://www.aerogel.com/_resources/common/userfiles/file/Data%20Sheets/Cryogel_x201_DS.pdf

Cryogel® x201’s unique properties

• extremely low thermal conductivity,
• superior flexibility,
• compression resistance,
• hydrophobicity
• ease of use

 

[Roger Caffin]

Hi Cameron

“If you adopted Rogers huge foam block pillow, you could put bottles in the holes.”

Remind me – where (URL) did I put the photo? I can’t find it !

Cheers

 

[Franco Darioli]

For Roger :

http://bushwalkingnsw.org.au/clubsites/FAQ/DIY_RNCDesigns.htm

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