A large molecule (macromolecule) composed of repeating structural units.
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1answer
28 views
Plastic: Reputable Publications
I would just like some reputable textbooks and or publication companies that have extensive research on plastics, as, for example, dealing with life cycles of plastics, degradation factors, effect on ...
1
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1answer
59 views
Solid hydrophilic transparant materials that don't dissolve in water
I am looking for hydrophilic transparant materials which are solid at room temperature and that don't dissolve in water. I need these for an experiment in which I condense droplets on a plate made out ...
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1answer
58 views
How long can polyethylene molecules be?
In this video, Steve Spangler says the substance he is using (a polyethylene oxide): http://www.youtube.com/watch?v=m-88M75_PCI
He mentions that one molecule would go to the moon and back twice! I ...
2
votes
1answer
99 views
Easily removable material that sticks to skin
I am looking for some kind of material that can be used to easily latch something to someone's finger. This is for a first year engineering project. The idea is to use this material to latch small ...
2
votes
1answer
159 views
How would I select the strongest Plastic Material?
Plastic Selection
I'm going to have an online machine shop build a part for me using a CAD drawing that I specify.
Typically, these parts are made of Aluminum, but this manufacturer also mills parts ...
1
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0answers
18 views
Why do big thermoplastics (like Polytetrafluoroethylene) behave like thermosets?
Why do big thermoplastics (like Polytetrafluoroethylene) behave like thermosets? I know for sure it has to do with the van der Waals force and the fact that the molecules are huge, but why? Why does a ...
2
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1answer
43 views
What is a 'Trace Crossing'?
I'm reading about electrodeposition of conductive polymers in a chemistry textbook, and the author mentions 'trace-crossing' in the 'potentiodynamic response'. From the context I can figure out that ...
4
votes
1answer
340 views
A thermoset or a thermoplastic?
How do you know if a polymer is a thermoset or a thermoplastic? For example:
hydroxybutanoic acid
2-amino-3- hydroxybutanoic acid
(I am not sure if these are correct in English)
I know what ...
7
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1answer
61 views
Why are smoke odors persistent in fabrics?
Obviously smoke is very complex, but apparently phenol compounds are the main components of wood smoke that produce the characteristic odor. (One of more significant of these compounds seems to be ...
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1answer
73 views
Polymer Slurry Fact
I watched a video on the construction of Burj Khalifa, Dubai. The construction engineers answered that they're using a special type of protection known as Cathodic protection to protect from the ...
2
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1answer
816 views
How to find the band gap for a compound?
I have processed a si/polymer hybrid using a silane coupling agent which I need to determine the energy gap / band gap. Would you please let me know the procedure to go about determining the band ...
4
votes
1answer
198 views
Are there any general chemical rules for choosing initiators for a polymerization reaction?
I'm working with some very basic free-radical initiated polymerization reactions. For the most part, I just follow a recipe I'm given (by a member of my group or the broader literature), it works, and ...
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1answer
931 views
The Chemistry behind creating Polylactic Acid (PLA)
I've seen a few videos of persons creating plastics from starch by adding an acid, glycerol, and water, however no explanation of the chemistry.
Does anyone know what $\ce{(C6H10O5)_{n} + C3H8O3 + ...
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1answer
132 views
Stiffness of chewing gum
My Sister asked me this:
"Why is it that when we chew gum, it is soft and mushy to begin with , but slowly gets firmer and firmer like after 20 mins of chewing?"
I think it is because when we ...
1
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0answers
93 views
How is silica bead bonded into polystyrene?
What kind of bonds silica bead forms with polystyrene? Silica is now as ~100 $\mu$m spherical particles in bulk polystyrene that is made by melting.
How can I bond the silica particles
more ...
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1answer
543 views
What is the difference between cross-linked bond and secondary bond in polymers?
There are two kinds of bonds between polymers in solid material: primary and secondary. Primary bonds can be also called cross-linked bonds. What is the difference between the two (strength, type, ...
4
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1answer
283 views
Living-cationic vs cationic polymerization
To my understanding, cationic polymerization is a type of living polymerization but my teacher's notes and Wikipedia seem to suggest they're different. I can't see the difference.
The same goes for ...
17
votes
2answers
247 views
How is Teflon adhered to frying pans?
The most notable characteristic of polytetrafluoroethylene (PTFE, DuPont's Teflon) is that nothing sticks to it. This complete inertness is attributed to the fluorine atoms completely shielding the ...
21
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2answers
532 views
How does chloroform degrade nitrile gloves?
Many of us have experienced the failure of nitrile gloves when exposed to chloroform. What's going on at a mechanistic level when this occurs?
I would guess that the chloroform dissolves some of the ...
6
votes
1answer
541 views
What is the mechanism of APTES mono-layer formation on glass substrates?
The reagent APTES is a fairly common "ink" for microcontact printing, a technique that forms covalent bonds between the silanols found on the surface of the glass and the silane in the the APTES. It's ...
5
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2answers
145 views
Polypropylene 55 gallon drum
Can a polypropylene 55 gallon drum previously filled with chemicals used in the chrome plating process (possibly Nickel Sulfate) ever really be "cleaned out" for re-use? Can polypropylene ever absorb ...
6
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1answer
481 views
How does Polytetrafluoroethylene (Teflon) differ from Polyvinylidene fluoride (PVDF) as a protein binding membrane material?
PTFE and PVDF (durapore) are both used in protein binding filter membranes (Millipore specifically). Chemically speaking the two polymers differ quite significantly due to the additional fluorides and ...
