I have 2 interesting questions, I believe, regarding polymer properties. I am designing a ball (pretty much like a basketball in size and appearance) to be used inside pressure vessels for certain corrosive fluids. The ball is inflated with air to a certain pressure in order to cushion extreme...
Hi,
I am designing an inflatable balloon (long and thin like those used to make balloon animals) with a purpose to support a force in a manner like a cantilever.
I am struggling to find literature/assistance regarding the calculations required to determine balloon deflection under a standard...
Homework Statement
Under which class of materials would the following materials be categorized?
What are/is the primary bond type(s) in each material/object?
a. Tennis Ball
Homework Equations
The Attempt at a Solution
We'll consider a very simple and standard tennis ball...
Hey all,
I'm trying to design a clamp that has to hold onto a hollow carbon fiber tube, approximately 2.5 inches in diameter. The clamp will be bearing a 15-20lb load. The carbon fiber will be at angles from 20-70 degrees from a vertical axis.
I'm curious if there is a polymer that can be...
Polymers
Polymers are defined as susbtances (natural or artificial) that are composed of smaller units called monomers. These monomers are molecules.
Molecules are an aggregation between two or more (similar or different) atoms.
That said, why are not all substances polymers? After all...
Hi everybody.
My goal is to design a process that, with no automated machinery (I'm using a mechanical pipette), would allow for extremely uniform coverage (that is, with minimal area of multilayers or empty spaces) of a hydrophilic surface with a thin film of polymer solution.
I would...
Hi
i wanted to know what are polymer melts. Googling did not help.
just had to read this theses which has me pulling my hair over this
any help/info/links would be appreciated
I'm looking to get some polymer blend sheets for some tests. Something like PC-ABS or PMMA-PC or something of that nature. Basically a mix of 2 polymers but NOT a co-polymer. Just a simple mix. I looked all over and haven't found anyone selling it. Thanks!
A polymer model -- 15.4-3
Homework Statement
A rubber band consisting of n polymer chains is stretched from zero length to its full extension (L=Na) at constant temperature T. Does the energy of the system increase or decrease? Calculate the work done on the system and the heat transfer to...
I'm an engineer student and I'm trying to build such a solar heating system that it is drum with two layers, inner one is a metal (aluminium alloy I'm thinking) water container and outer layer is made of polymer, with air gap in-between. When suns come out, it radiates through the polymer and on...
Hey Guys,
Been a while since my last visit, as I've been away for a well earnt break..
But recently I've been set a challenge and its baffling me some what, and i wonder if anyone can help pleaseeee:biggrin:
Basically long and short of it, a Car Manufacturer has been struggling in...
Hello colleagues!
I’d like to ask your opinion on the following information. I found an article where is talking about wonderful polymer that has very interesting properties to pick up parameters when applied on some surface including human body and to register information and to transfer...
It is a proof question. Does anyone can tell me how to do this question?question 22.2
it is the question for extra credit for my final exam.
thank you so much.
Hi,
I want to do a very simplified model to try to modelize the change of temperature in ultrasonic welding of polimers.
As a starting point, I only want to simulate the change of temperature of a 1D homogeneous polymer (viscoelastic solid) when I apply a constant pressure and ultrasounds...
Dear all, I am Levy , I am glade to take part into physics Forums, I hope I can share my know with everybody and study from you, Thank You!
I test the PET of creep deformation recent days, who has some reference about this aspect.
Thank you
Hi all
This is my first time here and I'm hoping first that I have reached the right forum for my question and that someone out there can help me! I am trying to model the energy dissipation of what is effectively a mass spring damper where the spring and damper are modelling a polymer. I...
Persistence length: What are the beginning and end points in an polymer?
Hello,
can you tell me where the starting point and the ending point of the (parts of the) persistence length in a polymer are?
I thought the persistence length was the greatest length that only just is not bent...
Which PVC to choose for polymer nanocomposite?
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I’m a final year Mehcanical engineering student. For my individual project, I have to fabricate PVC based nanocomposite using nanosilica. I haven’t been provided...
Homework Statement
Consider a polymer formed by connecting N disc shaped molecules into a one dimensional chain. Each molecule can align along either its long axis (of length 2a) or short axis (of length a ). The Energy of the monomer aligned along its shorter axis is higher by e, that is the...
Hello all, I am new to these forums and just registered.
I plan to be an active participant on here and reciprocate the generosity I've observed in other threads.
Im looking for a certain "material" that can satisfy this list of criteria that I've put together.
I'm pretty sure that I am...
I've got this problem where I've got a molten polymer (polyisoprene) in a region where I can imagine a cubic lattice. I am told that it has a density of 910 kg/m^3 and an entanglement molecular weight of 3.7 kg/mol.
earlier in the problem I have to figure out the molecular weight of an isoprene...
I am doing a science fair experiment testing the effectiveness of polymers commonly used in football helmets. I am planning on using polycarbonate and ABS, because they are commonly used. However, I am looking for one or two other polymers that are similar in strength and price to add more of...
Does the volume swell ratio relate to the weight gain when a crosslinked polymer is emersed in a solvent? Is it as simple as calculating (delta V) = (delta w)/density?
Homework Statement
http://www.facebook.com/photo.php?fbid=1612917330439&set=a.1250823718325.2039017.1461460506&ref=fbx_album"
The Attempt at a Solution
I don't want to ask about the full solution for this thing, but only one thing: in that expression, which is the kinetic energy and...
I am doing an experiment to estimate N, the number of crosslinked polymer strand in a piece of rectangular rubber. To do this, I attached weights to the rubber and measure the extension of the rubber when subject to the force. However, I found two equations that can be used to find N and they...
Few quick questions, too lazy to look up this info my self:
1. Whats the max molecular weight for a single polymer strand of styrne (i.e what's the max number of styrenes you can link up).
2. Anyone know about the industrial process to produce ABS?
3. What is a good solvent for Styrene...
Hi chemistry friends,
I'm currently working on a reaction to produce the following polymer: Cyclopentadiene functionalized polyketone.
I start with polyketone as a reagent and I should end up with the reaction product together with the solvent (THF) and water with NaOH.
My question...
The polymer is to be used for rodent housing (cage).
I need to find a polymer which has the properties shown below.
Polycarbonate
Before I go into the specification required, I have researched and have come up with polycarbonate.
As it has high impact strength, is 200x stronger than...
Homework Statement
How would the polymer of 2-chloro-2-butene look when formed by addition polymerization
Homework Equations
The Attempt at a Solution
I have attached my solution. Please tell me if i am right/wrong and why if it is wrong.
Dear all,
I'm trying to relate the concentration of moisture in an external environment with the concentration of moisture on the surface of a polymer. This is an adsorption and is it right to relate it using Henry's law? What is the explanation for this?
On a side note, what happens when...
Tell me what your ideas are for this multiple choice question
Compared to semiconductors, metals, and ceramics, polymers:
a) have lower melting points
b) tend to have lower densities
c) deform plastically to a higher extent
d) have lower electrical conductivity
e) all of the above
f)...
I'm trying to work out how much energy from sunlight will be absorbed (converted to heat energy) by a silicone polymer.
I need the mass attenuation coefficient (from what I can tell at least) so that I can work out the amount of heat energy the water inside a black silicone polymer container...
Homework Statement
For a continuous fibre reinforced polymer, use a diagram to explain how the Young's modulus of the composite varies with fibre orientation and fibre content.
Anywhere i could get any of this information? I've been googling with no success for a while
Hello everyone. I was wondering if anyone could recommend a source for Flory-Huggins theory on linear polymer chains. You see, I've been conducting an undergraduate research project concerning the topic. Every paper I look at, they simply quote an equation, and says that it follows from FH...
Dear Everyone
I am facing the following engineering problem. I "inject" light in a flat (6.5mm) Acrylic panel at the edges of it. Due the different refractive index of the Acrylic material (1.4) and air (1) 90% of the "injected light" experiments total internal reflexion. I need to get the...
Artificial polymer "muscles" that contract with electronic/magnetic stimulation?
Hi everyone! First post-- hope this is the right place for it! And just to let you know, I'm not an engineering professional. I'm asking this question based on a speculative industrial design contest for which...
I understand the mean square end-to-end distance of a polymer of stepsize b and number of units N is given by
\left\langle R^{2}\right\rangle = \sum_{i,j=1}^{N} \left\langle r_{i} r_{j}\right\rangle + \left\langle \sum_{i \neq j}^{N} r_{i} r_{j}\right\rangle
And that the cross terms drop...
Hi there, does anyone know which type of UV radiation would be most effective in polymer degradation or more importantly jet ink fading. Personally I think it should be UVC as it has the highest energy per photon but I could't find much about it so please help, it's very important as I'm behind...
Homework Statement
Draw the structural formula for a three-monomer segment of poly(1,3-butadiene) in which addition is 1,2 for the middle unit and 1,4 for the outer units, with double bonds Z.
Homework Equations
Markovnikov's rule: H goes to the Carbon with the most H's
The Attempt at a...
Is it useful simulating a 3-D structure of a polymer solar cell?
Is there a particular internal structure for a polymer solar cell which is most efficient?
Hi PF,I'm working on a semi-classical model for a group of rather strange polymers based on carbon, nitrogen, and oxygen. In this treatment, I'm approximating the bond length and bond angle to be more or less classical (ie. ball and stick). But I would also like to treat the dihedral angles...
I got this idea that I could maybe replace the heavy lead acid battery on my motorcycle with a lithium ion polymer battery. I found that you can buy batteries for RC cars that match the power requirements. The lead acid battery is 12 volts, 6Ah. It seams that L.I.P. batteries for RC cars are...
Homework Statement
Polymers are made of very long molecules, usually tangled up in a configuration that has lots of entropy. As a very crude model of a rubber band, consider a chain of N links, each of length l. Imagine that each link has only two possible states, pointing either left or...
Hello! I am a junior in a high school. Currently, I am exploring different different colleges and universities, only in the United States and America. Right now, materials science and polymer chemistry is really interests me and I want to know if anyone here can recommend a university...
I'm trying to calculate the structure factor for a polymer melt: S(q)=\sum_{k}\sum_{j}\epsilon^{i*<q>*<r_{kj}>}, but I don't know how to deal with the imaginary exponent...(the rest of the variable don't really matter, because I'm confused about how to deal with the exponent, but q is the...