Slow Drying Out

Well it's been about a month since we made the solid balls of g00. As I said, it may take a while for all the acetone to dry out. I began to wonder just how long it would take, so I took a hacksaw and went at the big ball. I cut out a little wedge to get a little cross section of the drying process. As you can see in the picture, the big blob has dried out about 3/8 of an inch from the surface.



Considering that the rate of evaporation will probably slow down, I estimate that it will take about 7o years for this process to finish. That's a real seat-of-the-pants estimate. After that, I took the hacksaw to one of the smaller blobs. I sawed that sucker in half. It's interesting cutting this stuff. When you're cutting through the hard stuff, it cuts well. As you get into the center, it's more like cutting through a squid. It's arduous. Anyhow, just like the big blob, the smaller blob was still pretty acetone rich in the center. In other words, it still reeked of acetone.



So this got me to thinking about mailing off the plastic challa bread to it's maker. I hope the trace of leaking acetone fumes won't set off some alarms and send the Homeland Security guys down on my ass.

By the way, that white bucket with the red lid in the first picture has a fresh batch of melted polystyrene foam for my entertainment.

Bye for now.

Making Blobs

One of the things you do when you lose your job but you haven't quite lost it yet is try to find things to fill your time. You're getting paid but after a while you get tired of sitting on your butt, surfing the web.

One of the neatest things one can do, which fills time and has little or no value, is melt styrofoam with acetone. Actually, it isn't really styrofoam but is instead "expanded polystyrene foam", which everyone who doesn't respect Dow Chemical's trademark, calls styrofoam anyhow. You know it as that white stuff used in coolers and packing material and coffee cups. What it is, is a little polystyrene and a lot of air. By adding acetone, you start to partially dissolve the polystyrene and release a lot of air. It's not really dissolution so much as solvation. No chemisty takes place in the process.

I guess one could argue that melting it makes the "expanded polystyrene foam" take up less space in the landfills and it does that remarkably well. But the real reason to do this is to have fun.

So I decided to do a little. First I enlisted the help of my humble but able assistant. She's always up for something a little off the wall. We started collecting a lot of the stuff. There was the stuff in the solvent boxes, which cushions the glass bottles during shipment. There were lots of coolers from the bio guys and gals. There was a variety of packaging for syringes and tubes and who know what else. Let's just say there's no shortage of "expanded polystyrene foam" to be found in a lab environment.

We gathered up a lot of this white stuff. Then, to get a nice visual effect, we eviscerated a number of Sharpie pens of different colors and dropped the inky insides of each into acetone squirt bottles. This gave us a variety of colored acetone solutions to shoot at the various "expanded polystyrene foam" products. When acetone hits the "expanded polystyrene foam", it melts to a goo, much like the faces in "Raider of the Lost Ark", when they opened up the Ark. If you use colored acetone, you get colored goo. Cool!!

We got a big plastic (polypropylene) tub and poured in a bit of acetone. We then started stuffing the white stuff into the acetone and watched it disappear into goo. After a while we had a good base and the melting slowed up a bit, so we started spraying down the pieces with the squirt bottles of colored acetone. This elicited squeals of glee from some in attendance. Then we squirted designs in the coolers and as they melted, we stuck pieces together to make a variety of creations. If something didn't look quite right, we shoved it into the acetone vat and reduced it to goo.

This process went on for a few weeks. If you got bored, you went down to the lab and melted more "expanded polystyrene foam" into a growing ball of goo. Eventually, this got to be boring, so we stopped and let a lot of the acetone evaporate while my assistant took a few days off. When she returned we had a nice workable blob. All the colors combined gave a dark green hue to the acetone wet goo.

When I say workable, it's important to remember that you're dealing with a ball of goo that resembles taffy but reeks of acetone. So it's important to wear good solvent resistant gloves and work in a hood. After a while, I decided to try something different. I poured off any excess acetone and added a lot of water. This dramatically lowered the acetone fumes and seemed to semi-seal up the surface so the vapors went down a bit and the surface turned into a greyish green. If you squeezed a bit on the goo, you could expose fresh dark green acetone soaked surface. So we pinched off a few bits of the big goo ball to play with. My assistant took one small blob and fashioned a piece of challah bread. I took a couple of small pieces and mushed them around. Right before I went on vacation (see below), I dropped the two smaller blobs into water and filled the vat with the rest of the big blob with water and left them for ten days. I left the challah bread out on the hood surface. When I came back, the two small pieces that I was playing with had hardened and the smell of acetone was essentially gone. The big blob still reeked of acetone. Here's how they looked (click on the pictures for higher resolution):


Although these things look kinda mushy, they're really quite hard at this stage. And here's a closeup on the big blob:


And here's the challah bread:


The challah bread was interesting because it was sitting on the bench instead of in water. Over the week I was at the beach the top got hard but the acetone couldn't escape from the bottom and so it stayed soft and supple. Here's a picture of the bottom:


It almost looks like one of those geode things. When it dries out, I'm going to send it off to it's maker.

And that's all I have to say for now about melting "expanded polystyrene foam". Maybe one day I'll calculate the volume of material that actually went into the big ball but I'll have to wait for all the acetone to escape. That could take a while.

Beach Pictures

We recently went to Sunset Beach for a week. We took some pictures. Here they are:

Beach August 2008