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.
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.
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.
(Pros and cons for each polymer is in journal #3)
We wanted to make polymer that acts as the back side of the phone case, so it should be comfortable to hold and convenient to use. That’s why we want our polymer to have the following physical properties:
Low stretch – A phone case shouldn’t soft and stretchy. We can test it just by stretching it.
Firm – In order for the polymer to protect the phone. Also, no one wants to use a case that’s soft and slimy. we can test by feel if it’s firm.
Sticky (only to flat surfaces) – Our whole purpose was to make a phone case that can stick. We can test it by sticking it onto a wall, see if it’s easily attached or removed.
Not moldable – We don’t want the polymer to easily take shape, because it would be really annoying for the user to adjust it every minute if it’s blocking the charger port, camera, etc. We can test this by trying to roll it into a ball.
Not sticky to hand – We only want it to be sticky to walls and tables, because sticking on to hand would be very inconvenient for the user. We will test this by holding on to the polymer for 15 seconds, and then removing it. See if it’s easily removed, and if there are any left overs on hand.
Rubbery – This is just a optional physical property we hope our polymer would have, so it improves the grip and feel of the case.
OUR FIRST PLAN
From what I said before in Journal #2, we decided to use gloop as our base polymer, and modify it to fit our goal.
Prorotype #1: We planned to add 3g of guar gum to thicken the gloop and additionally add some rubbery properties, and 5g of PVA glue to make the gloop more sticky. (We also added 5g of borax, I think we were just being dumb. There wasn’t a reason since it decreases the stickiness) The polymer didn’t stick to anything; it was probably because of the borax we added randomly.
Prototype #2: We did the same thing except that we took out the borax. The gloop has gotten much more sticky and the grip was much more comfortable, but also, without borax to decrease the stretch, our polymer was more moldable and stretchy (we want to change that).
*We took the prototype out of the bag after a week, that’s when we were done with prototype 4. It worked really well, since some of the liquid was probably dried up through out the week, so it was sticky and thick. We stuck our phone on it and placed it on the wall, and it did stick. This was probably our best prototype yet, however, it looked bad and the grip wasn’t that good.
Prototype #3: We wanted to make the next one thicker, so we took out guar gum and put in 2g of solid corn starch which thickens the polymer. Our goal was achieved, the new polymer had very low moldability and stretch. But again, it wasn’t sticky enough.
Prototype #4: We thought the stick was decreased because it was way too thick and solid, so we 4g of water. (we added 4g of borax again, so stupid) The water made the polymer more stretchy but did nothing to the stickiness.
After Ms. Lemly came in and told us about the environmental issues of some of the materials we used, we decided to try using only the environmentally safe materials — water, guar gum, and solid corn starch.
Prototype #6: For this prototype, used 40ml of white glue, 7g of corn starch, and 3g of guar gum. With too much glue and less material to thicken the polymer, it turned out to be too sticky and watery.
Specific Goal: To design a polymer who acts as a phone case and allows it to stick to flat surfaces. It should be easily attached and removed, also, it should be very durable even when exposed to air for a long period of time.
Targeted Audience: Millennials
Problems that will be solved by this polymer: When you put your phone on the table, it can be easily pushed off by mistake. But with this sticky phone case, it will prevent these kinds of accidents. Also, this phone case allows the phone to stick onto walls, this will be a huge convenience: people get to watch tv shows without holding the phone, or even follow tutorials (like a rubix cube video) without having to hold the phone with one hand.
(an example that is too sticky for our goal)
I think gloop works best for our design out of the three basic polymers. First of all, it can stick onto flat surfaces, and is not too sticky to cause a problem. Super slime doesn’t stick at all, and stretch-tastic slime is just a pain to remove. Second of all, gloop is the hardest of the three slimes. this is very important trait for a phone case, since no one wants to hold a soft and gross case. Finally, gloop has a better grip comparing the the others; the stretch tastic slime is just disgusting and it gets all over the place, and there’s a layer of sticky liquid on the super slime, which we don’t want that on our phones.
- What are polymers and how are they made?
A polymer is a substance that is composed of many simple molecules bonded together called monomers (in other words, it’s when many molecules of a simple compound joined together). A single polymer molecule might consist of hundreds to millions of monomers and may have a linear, branched, or network structure. The amount of monomers in a polymer determines the so called degree of polymerization. When there’s a large amount of monomers in a polymer, it tends to have a high degree of polymerization and it’s called a high polymer.
There are two ways a polymer can be created:
- Condensation polymerization reaction – A polymer is created, but also a small molecule is eliminated or lost.
- Addition polymerization – When two or more molecules joins together to form a single product.
PVA Borax Polymer
PVA solution can be made into a slime by adding borax. PVA is already a polymer, and in this case, it is providing back bone for the atoms that will be joined. When they are mixed, the chains of atoms becomes linked together. As a result, the new substance becomes more solid.
2. Synthetic materials are artificial materials made from different substances through polymerization. Synthetic materials are manmade and are not produced in the wild.
Two examples of synthetic material are rayon and polyester:
- Polyester derives coal, air, water, and petroleum. The fibers of polyester are made during a chemical reaction between acid and alcohol. In the reaction, multiple molecules combine to form a larger molecule which will stand as the basis for polyester. The molecules are extremely strong and stable, making polyester non-absorbent and stretch resistant.
- Rayon is comprised wood pulp or cotton. The chemical reaction for rayon to form is when cellulose, an organic compound found in wood pulp or cotton is extracted to form white sheets of pure cellulose. The sheets are then put in to sodium hydroxide. The sheets are then shredded and dried out to crumbs and are left in metal containers for a couple of days. It is then mixed with liquid carbon disulfide to make viscose solution which is then spun to yarn.
“Unsafe Slime? How Bad Is Borax, Really?” The Chronicle Flask, 28 Dec. 2018, chronicleflask.com/2017/08/07/slime-safety/.
“Rayon.” How Products Are Made, www.madehow.com/Volume-1/Rayon.html.
“Polyester.” How Products Are Made, www.madehow.com/Volume-2/Polyester.html.
Encyclopædia Britannica, Encyclopædia Britannica, Inc., kids.britannica.com/students/article/polymer/276496.
24 tributes, 1 survives. In the dystopian novel The Hunger Games, Suzanne Collins flawlessly characterized the protagonist, Katniss Everdeen, as a strong and responsible individual.
Katniss, the girl who was on fire, was seen as an impulsive and lethal contestant in the eyes of the capital; however, she’s actually a motherly character who always tries her best to protect her loved ones. “‘Katniss! Katniss!’ I can hear my name being called from all sides” (Collins 71). During the opening ceremony of the Games, Katniss attracted all the attention and admiration from the audience, outshining every other tribute with her burning outfit. “Without thinking, I pull an arrow from my quiver and send it straight at the Gamemakers’ table. I hear shouts of alarm as people stumble back. The arrow skewers the apple in the pig’s mouth and pins it to the wall behind it. Everyone stares at me with disbelief” (102). It was ridiculous to shoot an arrow towards people who are going to sponsor you, but while demonstrating her amazing shooting skills, Katniss was furious and shot without considering the consequences. “’Come on, let’s eat,’ I say and plant a quick kiss on the top of her head” (16). After the death of Katniss’ father, her mother couldn’t pull herself together, so she took the responsibility to take care of the Prim. When Prim was chosen as tribute, Katniss boldly sacrificed herself to replace Prim in entering the games, “’I volunteer!’ I gasp. ‘I volunteer as tribute!’” (22).
Katniss’ position and personality reminds me of Uchiha Itachi in the series Naruto by Masashi Kishimoto. Itachi had the talent in both ninjistu and genjistu, but he was later on forced into a mission to assassinate his brother, the person he loved the most. He just couldn’t do it. In order for his brother to live, he had to exile himself from the village he lived in his entire life, and bear the charge of treason. Both characters loves their family more than anything else and would risk their lives protecting it.
Citation: “Primrose Everdeen.” The Hunger Games Wiki, thehungergames.fandom.com/wiki/Primrose_Everdeen.
In Jennifer Donnelly’s Revolution, Andi is a teenager who was suffering from the loss of his little brother. As she was finding resources to write her essay, her dad took her to Paris and she found a diary in a hidden compartment of the guitar from the French revolution era. During this research, she met Virgil, and fell in love with him, and it was a hope for Andi.
Words can murder, scar someone for life, or bury them in guilt. Andi was supposed to be with her little brother while the accident happened. His father asked Andi again and again of when her brother died, and that put Andi in deep guilt and depression. “I play until my fingertips are raw. Until I rip a nail and bleed on the strings. Until my hands hurt so bad I forget my heart does” (Donnelly, 7). Even though his dad apologized for what he said, Andi’s heart has already been broken into pieces. She attempted to suicide at school, and also on the Eiffel Tower. “I see my brother. He’s not dead. He’s standing in the street, watching me. It can’t be. But it is” (Donnelly, 21). This left a deep scar in her life that cannot be fixed.