helzblack
Harmless
Posts: 31
Registered: 6-8-2019
Member Is Offline
|
|
OTC polymers
Which polymers you know of that are cheap and easy to make?
Silicone resin is useful and not that expensive, yet I wonder if this if there are cheaper polymers that can be used to make molds.
Urea-formaldehyde is fragile but very easy to make. Then using sodium silicate and ethanol makes something more plastic and elastic but it polymerizes
before it can take the shape of the object.
I am wondering. Are there plasticizers that are also OTC? Or any monomers that have a curing time, ie, they take time to polymerize.
Plasticizers seem to always be complicated organic molecules. What are your suggestions?
|
|
|
j_sum1
Administrator
Posts: 6306
Registered: 4-10-2014
Location: At home
Member Is Offline
Mood: Most of the ducks are in a row
|
|
What a broad question.
Choice of polymer depends largely on application.
Cost will vary widely depending on what you are doing. But need not be expensive. There is a recent YT video on making silicones from silicate kitty
litter. It does not get any cheaper than that. Milk is OTC if you want a casein-based polymer. You can process polystyrene to get styrene which
will then polymerise on its own even if you don't want it to. Perhaps the widest choice of monomers would come from depolymerising existing polymer
materials. That is essentially free. Then you can do what you want.
Like so many projects, you need to have a specific target before you can get any meaningful advice.
|
|
|
helzblack
Harmless
Posts: 31
Registered: 6-8-2019
Member Is Offline
|
|
I know of the kitty litter stuff but the problem is that the resulting plastic is not hard enough and it polymerizes too quickly. To make a mold,
something that is hard, but not too hard is needed, just like silicone resin.
That is why I asked either and specifically.
OTC plasticizers to make the urea-formadelhyde more plastic, less brittle
OTC inhibitors for the cross-linking that give the kitty litter plastic enough time to take on the shape, and form one single body instead of tiny
nodules.
|
|
|
helzblack
Harmless
Posts: 31
Registered: 6-8-2019
Member Is Offline
|
|
Alternatively there is a NileRed video where he extracts the plasticizer from vynil gloves but in low yields. I wonder if there is any way to extract
the plasticizers from other plastics in higher yields, reshape the plastic and then add it again? Or to partially depolimerize it, which I have heard
is hard, reshape and polymerize again?
|
|
|
Texium
Administrator
Posts: 4566
Registered: 11-1-2014
Location: Salt Lake City
Member Is Offline
Mood: PhD candidate!
|
|
You need to be more clear about what you want to do with this plastic to get the answers you’re looking for. Clearly you have a specific use case in
mind, but you aren’t sharing it. That’s not helpful.
|
|
|
Texium
|
Thread Moved
23-7-2024 at 04:38 |
bnull
Hazard to Others
Posts: 386
Registered: 15-1-2024
Location: South of the border, wherever the border is.
Member Is Offline
Mood: Dazed and confused.
|
|
Glyceryl triacetate is a plasticiser that is also used as food additive, hence OTC.
As said above, the question has so many possible answers, and these answers depend upon the destination, that the question is unanswerable as it is.
Would you mind to tell us what is the intended use of the molds? Are you casting metal, making candles or popsicles, counterfeiting sculptures?
Silicone can be used in molds to make candles but not in metal casting; litharge-glycerine, although not exactly a polymer, can be used for molds that
you want to use (practically) forever (since it gets even harder as it ages) but not with molten metals and strong acids; gypsum, not a polymer, can
be used with low melting alloys (I had no problems below 350 °C).
Quod scripsi, scripsi.
B. N. Ull
P.S.: Did you know that we have a Library?
|
|
|
helzblack
Harmless
Posts: 31
Registered: 6-8-2019
Member Is Offline
|
|
Molds for wax. Just something that is hard enough to take on the fine details in the wax, and elastic to remove the original model without breaking
the mold.
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
