Polymer Definition and 96 Threads

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...

can some one discuss this question ? Why does polymer swell ?how can be controoled ? Thanks

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!

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

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...

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?

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.

i need a very strechable, elastic noncombustible polymer. any suggestions?

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)...

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...

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...

Hey I am trying to find out if bitumen is a polymer, and if it is please direct me to resources where I could see its structure.Thanks

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 am trying to find a hydrophilic polymer that sublimes in vacuum (~ 10-7 torr). Can anyone help me or tell me where i could find one?

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...

Does anybody have a table of rolling friction coefficients? I can't find the one I'm looking for. I have a vertical door opening (similar to a garage door) where there are UHMW polymer rollers rolling in a track. I read somewhere that the coeff of rolling frict would be close to teflon on...

Minor in Polymer or not?? Hello guys, been a while since I've been in here. Well I'm a sophomore student studying chemical engineering on a full scholarship offered by the oil company where I live. After graduation I'll have to work for the oil company, equal to the number of years I study...

Homework Statement Please help me calculate the center of mass of the polymer (radius) from atomic coordinates (more than 2000) given in Armstrongs. Can anyone help with the formula? I need to calculate the radius of gyration of the polymer. Thanks. Homework Equations The Attempt...

Homework Statement 1D polymer, fixed segment length a If the angle between segment j and j+1 is 0, the energy is 0 If the angle is pi the energy is +2J. Compute the correlation function <s_i s_{i+n}>, where s_j = \pm 1 denotes the direction of segment j Find the persistence length Lp...

How would I name the polymer in the attached image?

Dear Members Greetings. I joined this forum today. I have done my BE(Electrcial) followed by MS(Telecommunications) and a 9 months Course on Systems Enginering from UK. Presently i am in South Korea on a Scholarship for my PhD in Nanoscience and Tech (Here is the problem). I have no...

Why is the flow behaviour or viscosity important in the case of polymer? This question is given when we had lecture about flow behaviour, viscosity, and rheology. Thanks a lot!

Hi, Why is it better for a cell to synthesize polymers such as proteins carbohydrates by linking together monomers than to synthesize them from scratch> I believe it is because it would take too much energy to link them together from scratch. Since they already have these monomers the...