Molecular weight dependence of the second virial coefficient for flexible polymer chains in two dimensions

1989 ◽  
Vol 22 (5) ◽  
pp. 2491-2496 ◽  
Author(s):  
D. Poupinet ◽  
R. Vilanove ◽  
F. Rondelez
Keyword(s):  
Molecular Weight ◽  
Virial Coefficient ◽  
Second Virial Coefficient ◽  
Two Dimensions ◽  
Polymer Chains ◽  
Flexible Polymer ◽  
Molecular Weight Dependence

scholarly journals On the Molecular Weight Dependence of the Second Virial Coefficient of Polystyrene in Toluene

1985 ◽  
Vol 17 (4) ◽  
pp. 657-660 ◽  
Author(s):  
Lina Zhang ◽  
Dajian Qiu ◽  
Renyuan Qian
Keyword(s):  
Molecular Weight ◽  
Virial Coefficient ◽  
Second Virial Coefficient ◽  
Molecular Weight Dependence

Molecular weight dependence of the second virial coefficient for linear flexible polymers in good solvents

1985 ◽  
Vol 18 (8) ◽  
pp. 1637-1638 ◽  
Author(s):  
Hiroshi Fujita ◽  
Takashi Norisuye
Keyword(s):  
Molecular Weight ◽  
Virial Coefficient ◽  
Second Virial Coefficient ◽  
Flexible Polymers ◽  
Molecular Weight Dependence

On the theory of the second virial coefficient for polymer chains

1992 ◽  
Vol 25 (7) ◽  
pp. 1912-1916 ◽  
Author(s):  
Hiromi Yamakawa
Keyword(s):  
Virial Coefficient ◽  
Second Virial Coefficient ◽  
Polymer Chains

Partitioning of charged and neutral dextran-dye derivatives in biphasic cellulose nanocrystal suspensions

2008 ◽  
Vol 86 (6) ◽  
pp. 503-511 ◽  
Author(s):  
Stephanie Beck-Candanedo ◽  
David Viet ◽  
Derek G Gray
Keyword(s):  
Molecular Weight ◽  
Partition Coefficient ◽  
Cellulose Nanocrystals ◽  
Partition Coefficients ◽  
Virial Coefficient ◽  
Total Concentration ◽  
Second Virial Coefficient ◽  
Fluorescein Isothiocyanate ◽  
Blue Dextran ◽  
Molecular Weights

The partitioning behaviour of dye-labeled dextrans of high molecular weight in aqueous suspensions of native cellulose nanocrystals was studied. Cellulose concentrations lie in the isotropic–nematic coexistence region. Blue dextrans of various molecular weights and degrees of substitution of dye molecules (anionic Cibacron blue 3G-A) were investigated. Increasing the total concentration of blue dextran and degree of dye substitution led to increasing partition coefficients. Increasing dextran molecular weight resulted in higher partition coefficients, in agreement with theory. Partition coefficients were larger than predicted theoretically using a second virial coefficient approximation. Electrostatic and entropic contributions to the partition coefficient of blue dextran are discussed. Dextrans labeled with neutral fluorescein isothiocyanate did not partition preferentially in this system.Key words: partition coefficient, cellulose nanocrystals, dextrans, degree of substitution, polyelectrolyte.

scholarly journals Molecular Weight, Osmotic Second Virial Coefficient, and Extinction Coefficient of Colloidal CdSe Nanocrystals

2002 ◽  
Vol 106 (21) ◽  
pp. 5500-5505 ◽  
Author(s):  
A. Striolo ◽  
J. Ward ◽  
J. M. Prausnitz ◽  
W. J. Parak ◽  
D. Zanchet ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Extinction Coefficient ◽  
Virial Coefficient ◽  
Second Virial Coefficient ◽  
Cdse Nanocrystals

Collapse of Isolated Chains in a Network

1994 ◽  
Vol 376 ◽  
Author(s):  
R. M. Briber ◽  
X. Liu ◽  
B.J. Bauer
Keyword(s):  
Crosslink Density ◽  
Virial Coefficient ◽  
Linear Chain ◽  
Second Virial Coefficient ◽  
Polymer Chains ◽  
Network Density ◽  
Radius Of Gyration ◽  
Single Chain ◽  
Polystyrene Matrix ◽  
Wide Range

ABSTRACTIn this study we use small angle neutron scattering to investigate the conformation of linear deuterated polystyrene chains trapped in a crosslinked protonated polystyrene matrix. The second virial coefficient was obtained as a function of crosslink density for a wide range of crosslink density. It is shown that the second virial coefficient decreases with increasing crosslink density. By extrapolating the scattering to zero concentration of the linear chain at all values of q, the single chain scattering was obtained and radius of gyration was measured the function of network density. It was found that when the network density is low (NI < Nc where NI and Nc are the number of monomer units in the linear chain and the monomer units between crosslinks, respectively) the radius of gyration does not change. As the network density increases (NI > Nc ) radius of gyration decreases. In this region the inverse of the radius of gyration varies linearly with the inverse of Nc. When the crosslink density is very high (NI » Nc ), segregation of linear polymer chains occurs. These results are in agreement with prediction and computer simulation results of polymer chain conformation in a field of random obstacles where the crosslink junctions act as the effective obstacles.

Size, Form and Flexibility of the Rubber Molecule

1962 ◽  
Vol 35 (4) ◽  
pp. 908-917 ◽  
Author(s):  
G. V. Schulz ◽  
A. Mula
Keyword(s):  
Molecular Weight ◽  
Electron Microscope ◽  
Light Scattering ◽  
Virial Coefficient ◽  
Second Virial Coefficient ◽  
Quantitative Measure ◽  
Degree Of Polymerization ◽  
Bromine Content ◽  
Angle Scattering ◽  
Gaussian Density

Abstract Natural rubber can be brominated in dilute cyclohexane solution, whereby the molecular weight, corresponding to the bromine content, increases. For brominated rubber, increasing bromine content makes cyclohexane an increasingly poorer solvent, which is shown by a contraction of the molecule coils and a decrease in the second virial coefficient. Quantitative results were obtained through viscosity and light scattering measurements. Cyclohexane solutions of brominated rubber containing about 43% bromine have a θ point at room temperature. Here the second virial coefficient is zero and the coil has an ideal Gaussian density distribution. In this state the coil diameter is about 1.6 times bigger than for completely free rotation. A comparison of these data with X-ray low angle scattering could yield a quantitative measure of possible molecular branching. Brominated rubber with about one bromine per isoprene residue is a good starting material for the preparation of electron-microscope samples which can be used for the determination of the molecular weight distribution in rubber. The value of the weight average degree of polymerization determined by an electron microscope is in agreement with that determined through (1) light scattering and (2) ultracentrifuge and diffusion measurements. The molecular inhomogeneity of our sample is of the order of 0.5.

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