Thermoplastic

dangerstudios

dangerstudios

Active Member
So from what i've heard, thermoplastic is softish plastic that can easily be heated to a liquid and pourd into silicon molds, were it cools into sandable, cutable plastic. Have I heard correctly?
 
I thought thermoplastic was just a term that described plastic that could be heated and change its shape, like acrylic can be heated and bent and when cooled retain that new shape.

Though I don't think that means it wouldn't also describe what you're asking about.

Somebody else will probably know better though.
 
A thermoplastic is one that can be heated, melted and injected into a mold. Then there there is a plastic resin, where chemicals are mixed together to form a plastic.

If you want something pourable, you would probably want a plastic resin. Thermoplastics are usually injected, and use a mold that can take the heat. I'm not sure if silicone could take the heat of a thermo plastic. Usually thermoplastics need a very specific temperature range that they need to be heated to or they burn.
 
Thermoplastics are polymers that when heated become a liquid. They then lose that heat and become solid again. They can be remelted and used again.

Thermosets are polymers that are usually mixed from two separate liquids. They harden by means of a chemical reaction that gives off heat as it sets. They cannot be melted, they just burn.

There is a product out there called polymorph. I think that might be what you're looking for. This guy uses it to build an Iron Man arc reactor.

How to make an Iron Man Arc Reactor
 
Thank you, Exactly what I was looking for. So if I heat that stuff to a liquid, would I be able pour pour it into a plaster or silicone mold?
DrewSmith007 said:
Thermoplastics are polymers that when heated become a liquid. They then lose that heat and become solid again. They can be remelted and used again.

Thermosets are polymers that are usually mixed from two separate liquids. They harden by means of a chemical reaction that gives off heat as it sets. They cannot be melted, they just burn.

There is a product out there called polymorph. I think that might be what you're looking for. This guy uses it to build an Iron Man arc reactor.

How to make an Iron Man Arc Reactor
Click to expand...
 
I don't know, never used the stuff. From what I've seen it is usually just heated until it's pliable then worked into shape. I've seen pictures of things that look cast though. If I remember correctly, it's soy-based, so it might burn easily.

YouTube - Polymorph Casting - How to

From the title it looks like you can pour it. If I were you though, I would go with a 2 part resin. There's not much doubt about its durability.

BITY Mold Supply - Mold Making, Mold Rubber and Casting Resins | Home

Those guys have all sorts of casting supplies, and lots of instructional videos. I'm not affilitated with them, just a fan.

Good luck.
 
DrewSmith007 said:
I don't know, never used the stuff. From what I've seen it is usually just heated until it's pliable then worked into shape. I've seen pictures of things that look cast though. If I remember correctly, it's soy-based, so it might burn easily.

YouTube - Polymorph Casting - How to

From the title it looks like you can pour it. If I were you though, I would go with a 2 part resin. There's not much doubt about its durability.

BITY Mold Supply - Mold Making, Mold Rubber and Casting Resins | Home

Those guys have all sorts of casting supplies, and lots of instructional videos. I'm not affilitated with them, just a fan.

Good luck.
Click to expand...

Huh! I've never heard of this polymorph stuff before. I guess i'll have to give it a try sometime.
 
Can I asked why you would go this route over 2 part urethane resin?

I know there are reasons but I'm curious to yours, as playing with molten hot plastic outside of the controlled sealed environment of an injection molder is only asking for trouble...

If you are looking for something like Polymorph that never actually liquidizes but just gets soft then hit up the local craft or art stores and get some 'Friendly Plastic' Hobby Lobby and Michaels generally carry it... But you are not going to 'pour' it, you are just going to free form it while it's soft...
 
Polymorph, aka Friendly Plastic is good for basic shapes only. It cools rapidly and will not fill a mold quite the way you think. Imagine fresh taffy. It won't pick up any detail. Buy the $30 kit from Smooth-On, or another vendor's resin starter kit.
 
Sounds more like you want a high shore silicone or urethane rubber, and yes, every vendor carries some. TAP Plastics, Smooth-On are my personal favs.
 
dangerstudios said:
Are there any resins that cure translucent eniught hat leds can shine clearly through, and are rubbery?
Click to expand...

Clear Flex® Water Clear Urethane Rubber | Mold Making and Casting Materials Rubber, Plastic, Lifecasting, and More

The shore 95 will be like skate board wheels, a real hard rubber, the shore 50 will be like a soft rubber gasket...

Call and confirm with Smooth On first but you should be able to blend them to get everything between 55 and 95...

Tint to your color with pigments or even mix in other colored urethane casting rubbers (again consult with Smooth On first) to get a rainbow of colors...
 
dangerstudios said:
Thanks for the link. 95 should work for me. Any ideas on frosting it?
Click to expand...

All you need to frost it is urethane friendly pigment Smooth On's so strong pigments will work fine, you will need to experiment with the amount of pigment to get your desired look... But that is a lot easier with clear resin as it doesn't color shift nearly as much as other resins when they kick...
 
dangerstudios said:
What does "kick" mean?
Click to expand...

Kick = the moment they start to change from liquid to solid... Most urethane resins are a clear or amber color when liquid and turn to a bone or white color when solid... So pigmentation can be tricky... Take for example green, when liquid you might add pigment to a deep emerald green color, but when it turns solid you will end up with a soft baby pastel green... The shift with clear resins is not nearly as drastic...

From your questions it appears you don't have much experience, may I suggest you get some regular generic grade casting resin and learn the ropes before you dive into the long cycle time rubbers... With normal resins you can kick out castings every 15-30 minutes so you can get a lot of trial and error quick... With the rubbers like this you get one every 16-24 hours, so the learning curve can take exponentially longer...

One word of advise on the urethane rubbers especially clear use a digital scale and be precise! MIX, MIX, and MIX again once you combine the components... And then pour into a new container and MIX again, and MIX again for good measure... They are incredibly temperamental...
 
You must log in or register to reply here.
Back
Top