Questions tagged [polymers]
Polymers is concerned with the physical properties of individual macromolecules. For questions regarding bulk behavior of ensembles of polymers, the [condensed-matter] tag may be more appropriate.
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Can anyone explain this condensation pattern?
What is the hair-like "polymer" that condenses on the caps of the plastic cell vial? Inside vial are cells in a mixture of FBS and DMSO. The vials were frozen slowly in a special isopropanol-filled ...
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How can the presence of a solvent be included in a polymer bead-spring model?
I have a bead-spring model of a polymer melt and I would like to simulate what happens when a solvent is added to the system.
The most direct way to do this would be to add solvent particles into the ...
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Pressurizing with nitrogen vs vacuum? [closed]
pressurizing with vacuum causes volatilization of liquid.
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Molecular Dynamics Software for Coarse Grained Polymers
I am looking around for MD software that I can use to simulating polymers and I can't decide which software I should use.
I would like to simulate the swelling of crosslinked polymers, and I would ...
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Standard linear solid model - dashpot "short out" at $t=0$
My professor said that at $t=0$ the dashpot in standard linear solid is "short out". Why?
I know that the force of dashpot is ($u$ is the dislplacement):
$$F_{\eta}=\eta \space \frac{du}{dt}.$$
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Stress relaxation time scale [closed]
What is the definition and physical meaning of "stress relaxation time scale" in (non-Newtonian) fluids?
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Electret analog of Curie temperature
If you heat a permanent magnet above its Curie temperature then individual dipoles re-align to cancel each other out and it loses its strength.
An electret is the electrical analog of a permanent ...
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What do people mean with "per unit volume" in polymer solutions theory?
I am reading Modern Theory of Polymer Solutions by Hiromi Yamakawa and in the context of the virial expansion the following puzzles me a bit:
"...expanded in terms of solute concentration $c$ (in ...
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Scaling argument for friction force on a chain in shear flow
In her paper entitled "Deformations of One Tethered Chain in Strong Flows", the author makes the argument that given a shear flow velocity $v_x(y)=sy$ in a solution of viscosity $\eta$, and a tethered ...
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Partition function for polymer chain
Supposing that I have linear chain with polymer of $N$ identical particles (interacting harmonically with adjacent particle) with position of first and last particle fixed, how do I find the partition ...
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Is a folded protein's conformation subject to thermal fluctuations?
In biology class we learn that proteins are folded, and that the shape the protein takes affects its bioactivity. Typically we don't go much further into protein shape from that, at least not at the ...
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Hindered rotation model for flexible polymers: deriving the Flory characteristic ratio
In the hindered rotation model we assumes constant bond angles $\theta$ and lengths $\ell$, with torsion angles between adjacent monomers being hindered by a potential $U(\phi_i)$. In Rubinstein's ...
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Difference in viscosity-concentration and reduced viscosity-concentration graphs
I prepared 3 different polymer solutions with varying concentration of 100, 50 and 25 ppm in order to measure their viscosity . When I plot concentration vs viscosity graph in the excel, I have a ...
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Why polymeric solids are said to be intermediate between crystalline solids and amorphous solids?
Crystalline solids have ordered arrangement and amorphous solids do not. Polymeric solids are simply formed by the joining of some monomeric units. It has nothing to do with ordered or not ordered ...
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Effective length factor of a polymer in solution
If one wants to calculate the force needed to buckle a polymer in solution with Euler buckling, what would the effective length factor be? The polymer is free to move and rotate in solution as it sees ...
