Polymer Journal #5



2. Trial 18, the final trial, was the most successful prototype we made because of the different packaging, ingredients, and handling. It is able to hold a phone onto a wall for more than 20 minutes, has a comfortable grip, and does not stick to our hands. When we stick the polymer on the phone and held it, it had a smooth and comfortable feeling.; when we did the sticky test, where we held the polymer for ten seconds and see if it sticks to our hands, it came off easily. Prototype 18 can stick on the wall for more than 20 minutes because we added 5ml of PVA glue and also because we rest it for 48 hours without touching it. If we hold the polymer right after it is made, the oil on our hands cancels out the stickiness. The polymer has a comfortable grip because we have added the guar gum bit by bit and mixed really well, so there are no leftover pieces of guar gum in the polymer like what happened in prototype 2. Prototype didn’t stick to hands because we didn’t use huge amounts of glue and PVA like what we did in trial 4, so we balanced the amount of glue used so it sticks to certain objects but not to our hands.

3. To start off our experiments, we planned out which of the original slimes match our goal more, which was gloop. Then, we analyzed the specific effects of each material and started to test. For example, our ideal polymer needed high stickiness, so we tried to add PVA which increases the stickiness. We had multiple trials which are not very successful, but we were able to gain knowledge from every try. After each trial, we discuss which material caused what to happen, and what we might have done wrong in this prototype. After that, we create and improve, we learn from our mistakes and modify the previous ingredients thoughtfully.

Our presentation to the Dream On Team wasn’t really successful. When I got up there, I was really nervous. I forgot to explain half of the ideas that I’m supposed to about our goal, and I also screwed up when answering the questions after the presentation. The Dream On Team asked me how long could the polymer hold the phone on the wall. I wasn’t sure because we haven’t tested it before, so I wanted to be careful about how I answer it. I told them that it could at least stick for one minute. But after the product pitch, Kelly and I were interested in how long it actually holds, and it turned out to stick for more than 20 minutes. Another thing is that I feel like Kelly and I didn’t have much energy during the pitch, comparing to the other groups.

In the past experiments we’ve done, we couldn’t figure out a way to reduce the two ingredients that are harmful to the environment: PVA glue and borax solution. When we decrease the amount of borax used, the polymer would take shape and becomes a liquid blob. When we decrease the amount of PVA glue, the polymer doesn’t function because it has no stick. Since we didn’t have more time to figure out a better way, we decided to switch gears to making an environmentally friendly package. We agreed not to use plastic in the packaging, but it also had to be airtight in order for the polymer to sustain for a long time. So I came up with the idea of using a metal box. Where we used metal that has already been recycled to make our packaging.


Hydraulics: Scissor Lift

One thing I learned about hydraulics is it uses Pascal’s principle. Because the liquid in the pipes is incompressible, the pressure must stay constant all the way through it, even when you’re pushing it hard at one end or the other.

One obstacle I encountered is that I wasn’t really accurate in the measurements, so it really bothered me for the rest of the project. We really had to be precise in drilling the holes so it can be put together perfectly.

My greatest success was that even though my measurements weren’t accurate, but I was able to fix it at the end: I adjusted the positions of the popsicle sticks from my original plan.

DT Robot Petting Zoo

The biggest success was that we got to finish it in 3 classes, and it works. Since I missed 2 classes due to a field trip and my partner missed three. But we worked on it after school and got it done.

One thing I would like to change was maybe adding more features to the elephant. Just the nose moving was too plain. We could add sound easily, maybe add some elephant tusks, or even make the ears move. This can all be easily done since the programs are all pretty simple.

One thing I learned during the process was how to program on snap4 Arduino. Our group basically combined the 2 basic program that Mr.Layman taught us.