By the way this also relates to why “pull and snap” is a thing. In a glassy material, stretching something fast at a high temperature is physically the same as stretching it slow at a cold temperature. The faster you move it, the more “cold” it’s behavior is. If you pull something fast enough, it acts as if it’s so cold it’s below it’s glass transition and snaps. You can easily see this effect with silly putty. It is called time-temperature superposition and let’s you measure the behavior of substances at a given temperature without actually having to reach that temperature.
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Are you suggesting that THC (not THCA) can form glass-like shatter states but not lattice-structured crystals?
To my knowledge this is incorrect. I am fully under the impression that decarbing Shatter to THC is a non-reversible process that permanently alters the physical consistency of the Shatter to an oil-based form. THCA is a solid at room temperature, THC is a highly viscous oil at room temp.
If this is the case, then the decarbing of the molecule alters its ability to form intermolecular bonds, such as is described by @Photon_noir
@MagisterChemist Are you suggesting that THC can be forced into a shatter-like state at very cold temperatures? If so, is there a limit on what molecules can form glass-like states, or is temperature and contamination the two major factors?
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Practically speaking, the difference is temperature. THC and THCA both form glass. The difference is THC isn’t glassy at room temperature but needs to be cooled somewhat for you to see this. If you take pure THC distillate and lay it on wax paper like shatter, you’ll be able to bend and deform it. But if you cool it down to like -20C (typical freezer) it will definitely shatter, just like glassy THCA does at room temperature.
A non-crystalline substance doesn’t have any discrete melting point. It has a soft transition from a hard-glass “shattering” state to a malleable state that gradually increases in flow with temperature. At the fuzzy boundary of this state the behavior is unstable. It seems the glass transition of these impure THCA extracts is very close to room temperature. That accounts for why people have such difficulty getting stable shatter. The slightest change can lower the Tg to where it’s malleable at room temperature, and even stable shatter will start to be malleable on a really hot day.
Decarbed THC seems to have a lower Tg so in most circumstances it does flow at room temperature (not much though… THC distillate is a very tough solid, and you don’t have to cool it much to make it glassy).
Absolutely, and I wouldn’t even call a kitchen freezer “very cold”. I bet if you laid some THC distillate in the snow on a winter day, that would probably be enough to make it shatter.
Almost any liquid can be turned into a glass. For things that don’t form crystals, it is their natural state as they cool. For things that do form crystals, you need to cool them very rapidly, fast enough that they pass the Tg and harden before there’s been a chance to crystallize.
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When I read about making hard candy and thought about how it relates to making shatter, these are the conclusions I made.
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@MagisterChemist said it best already, but pure (decarboxylated) THC and the semi-solid solution of THCa that is raw Cannabis resin are both dilatant fluids (i.e. shear-thickening or non-Newtonian) when warmer and amorphous solids (glass) when colder. Hit them hard and fast and they will both chip and break. Press them slow and gentle and they will both smush and ooze.
Pure THCa is capable of crystallizing. It can also crystallize by precipitation and nucleation from solutions. Crystalline solids are not the same as amorphous solids. They do not behave the same way, either.
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This is the statement you said before that I was refuting to before of thc-a beeing a slight diffrent crystal
Never was able to find it on here but I was sure I read it
Thx
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