You redissolve the BHO in Ethanol, filter it, and place it in the freezer for a minimum of 48 hours, before filter a second time to remove the waxes.
You can get a thin film by starting with 1/4" of saturated oil and alcohol, and cold boiling away the alcohol at 115F and -29.9" Hg.
You can also get a thin film from raw oleoresin, by smearing a small amount in a Petri dish and heating until it spreads out and thins out all by itself.
If I dab BHO with the waxes still in it, I get a coated lung feeling too. Oil that has been winterized doesn't produce that same effect.
I'm pretty sure Oil Slick won't offer a dish, as they don't recommend spraying butane directly on their pad.
They have agreed to send Skunk Pharm Research one free for testing, so we will report back with more info after we have done that, but the alkanes cause silicone rubber to swell, and shed some surface particles left by the manufacturing process.
Here is Joshua's reply to my request for a test sample:
Hi Greywolf,
I am sure you know, silicone swells in the presence on non-polar solvents. Hexane is actually used as a “swelling agent” for silicone tubing to allow for an easier connection.
The swelling effect is the primary reason why silicone makes a poor compatibility choice when selecting a material to come into prolonged direct contact with non-polars.
As you must also be aware, chemical contamination from “extractables” in silicone materials, (in a procedure such as you are describing) is due almost entirely to the physical release of low molecular weight siloxanes, and other impurities from the manufacturing process.
This is why Tygon 3350, or SaniTech-Ultra, are made with platinum cured silicone rather than the more common peroxide cured variety. This is also why We use platinum catalyzed USP6 silicone in our pads. (rather than peroxide/food grade).
As far as I am aware, we are the ONLY company doing this. The cost of material for a simple “baking mat” would be prohibitive in that industry.
For the record (sometime I feel like a broken record)We do not sell the Pad to spray directly onto. Many (many) folks do, and when we realized it (july of 2012), we switched the silicone we use as our raw material as a prophylactic measure.
We also removed the Logo from our pads, because we feared that immersion in non-polar solvent could act to weaken the bond between that thin layer of logo silicone, and the pad beneath.
As concerned as we were about the logo....i cringe when I see folks spraying into parchment. The matrix of silicone in common parchment paper (non-Quilon / silicone coated) is extremely fragile compared to a pad. I imagine the violence of swelling and shrinking on that scale would be tenfold compared to the effect that prompted our own change of material.
The physical wear of swelling/shrinking/swelling/shrinking along with the various stresses inflicted by the innovative public (razor blades, torches etc...) make any sort of performance warranty unmanageable.
So we make em as pure as it gets, and when people ask us....we tell em that if they insist on using them this way, to please discard them if they notice any physical degradation.
I would refrain from cutting the pad to perform your testing, as this will expose the inner weave. Once cut or torn, the physical consequences of swelling could lead to damage along the exposed area.
Let me know where to send it, and I will get a Pad out to you today. Always happy to hear your thoughts. I redacted about 2 pages of hyper technical diatribe from this email.... because I figured you have likely done your own research regarding Pt cured silicone, and the various plasticizers that are used in food grade silicone. This is understandably a topic quite close to my heart; and I will be vary happy to discuss at length should you have specific questions (or non-specific musings?).
Also, should you require it, you have my explicit permission to share anything we discuss with whichever forums you are involved in.
Regards,
Joshua
