MOLTEN GLASS VS Prince Rupert's Drop - Smarter Every Day 285

There's a whole lot to be said for YouTube videos that are five to ten minutes long. I can show an entire five to ten minutes in class without committing a full bell. The video likely has enough information to be useful but not so much as to be rambling around and further on a topic than I need to it.

But YouTube's algorithm seems to be killing those five- to ten-minute videos in favor of either long videos (between thirty and forty-five minutes from what I can tell of the posting patterns of my favorite YouTubers) and shorts that are less than a minute and a half.

I'm not happy about that.

...but I am thrilled about the video that I'm posting today and that is clearly too long to be shown in class on a whim. Today's nearly thirty-minute long video is a brilliant exploration of phase transitions of glass.

It starts with Destin recapping what Prince Rupert's drops (PRD) are, something he's covered in way more depth, then goes on to let Cal from Orbix hot glass - also from that earlier PRD video - try to capture a shattering PRD inside a class prison - rather than the epoxy prison that Destin tried to use previously.

Then at about 7:00 the stress-strain curve shows up, and we start to see that glass isn't quite as simple as we'd been lead to believe previously.

And a graph of viscosity versus temperature blows it all away around 8:00 where we hear that glass is a second order (more info here and here) transition material.

...and I was hooked. Destin continues to produce some of the best science content on YouTube. 

Scrub Daddy Science

I bought a Scrub Daddy a couple of years ago and have been using it to demonstrate glass transition in polymers since then. It's good, however, to know a little more science than what I've been explaining ("it's a polymer, and they have phase transitions from rigid to flexible").

The above video shows the phase transition and the 2012 patent (linked here) for the Scrub Daddy. The blog entry associated with the video has more information as well as data from a few experiments (FTIR, for example) done with the Scrub Daddy.

In a semi-exciting detail, the video also shows that the thermoplastic polymer from Education Innovations is the same polymer as the Scrub Daddy. Conveniently, I already have that product in my storage room.

How cool is that?

But wait, there's more...





And also a video that I don't understand in the least. It's a wordless video of somebody pouring slime on a Scrub Daddy and squishing it with what I believe to be added sound effects. Clearly the internet it the realm of the long tail.

Build and Modify the World Around You with FORMcard | WIRED

I need to buy myself some Formcards (available here in the US - don't search Amazon because their selection is crap and ridiculously pricey).

I really dig the colors, and I'm looking forward to using them to demonstrate the idea of glass transitions in polymers (something we've seen before on the blog).