Good Afternoon Beautiful People!
Post number two of my blog and hopefully on the way to a habit. I really appreciated those of you who had a keen enough eye to tell me where I'd slipped up. You guys are awesome because as I said I am using these notes as a study resource so you may have saved my future self some confusion as I revise for all my exams at the end of the year. I hope people learned some stuff (or revised some stuff for all of you smarties who already know all about linear independence). Onto post number two...
Apparently My Carpet is Cream Coloured
Today I got my act together and tidied my room! Dad, if you ever read this blog here is photographic evidence that my floor still exists.
I love tidying my room almost as much as I love game of thrones (and I love game of thrones a lot!). These two passions of mine are slightly connected by the fact that I found game of thrones audio books on youtube... Speaking of game of thrones the coolest cool cat of all is coming over to watch season 3 with me tonight. Tessa, prepare yourself for the continuation of George RR Martin's soul crushing plot!
Thermoset and Thermoplastic Polymer Challenge
So we're going to do a bit of a murder mystery minus the murder. Most of this is a bit of revision for me because it was pretty much all in my chemmat 101 class. But its still super fun to go over and relevant to my 747 paper. Below is a picture of me holding up two types of pastics (and no I do not think metal is a plastic, I'm talking about the handle of the steamer pot). One of them is a thermoset and the other is a thermoplastic. See if you can guess which is which when I've finished explaining why they are different at a molecular level. Good luck Sherlock!
Firstly, I wanted to introduce you to the concept of Mers (something most chem heads will know about). Mers are the building blocks of polymers. They are simply a repeating chemical structures which are able to link together to form long chains. Think of them like beads on necklaces if you want. Then imagine that your chunk of polymer is a pile of beaded necklaces. And depending on how long the necklaces are and whether the beads are covered in Velcro you will get different properties from this pile of beads. You may be able to add a little bit of force to tear them back apart or else the pile may be so tangled and stuck that trying to separate them will only destroy all of your precious jewelry. Keep this in your head. You're doing awesome :)
Thermosets are made by pouring Resin (which is maybe a sort of plant secretion) into a mold with a catalyst, mixing it all up with maybe a little bit of heat and leaving it to cure or set! At a molecular level this results in a network of criss crossing polymers. A chemical reaction was what caused the plastic to set so there are strong covalent bonds or cross links joining the strings of polymers. You can never reverse this process. And if you try to heat the polymer up its only going to burn away leaving only a wonderful smell and some carbon behind. Imagine taking all your beads and putting them into a bucket and then squirting superglue into the bucket, swishing all the beads around and leaving it to dry. Are you ever going to reclaim your favorite string of beads for the party on Saturday? ONLY IF YOU DESTROY ALL YOUR NECKLACES IN THE PROCESS!
Thermoplastics have got their own thing going on. Things made out of thermoplastic are formed by taking some itty bitty plastic pellets or solid stock, adding some heat and rolling them out and reshaping to get whatever you want. The strings of polymers are connected through secondary bonds or Van Der Wal bonds. These are much much weaker than covalent bonds and can be broken with a little bit of heat. This means that thermoplastics can be processed over and over and over again as long as you don't dump them in landfill. Lets look at your necklace pile again. This time you've stuck them in a bucket without super glue and given them a stir. Even though they will get mega tangled, you're still able to extract them using a little bit of time and finger power and wear them to the Party on Saturday.
So have you got it? The milk bottle is recyclable and not as rigid as the handle. Also the handle is used in a high heat application making it a little inappropriate if it changed shape every time you steamed some veges. Bottle = Thermoplastic and handle = Thermoset! Yay!
More on these later! But for now I have a lecture to go to and two classes to teach then GOT to watch :)
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