Quantitative Determination of the Combined Styrene in the Butadiene-Styrene Copolymers

1972 ◽  
pp. 255-262
Author(s):  
E. Cianetti ◽  
G. F. Pecci
Keyword(s):  
Quantitative Determination ◽  
Styrene Copolymers ◽  
Butadiene Styrene

Electroanalytical determination of styrene in acrylonitrile-butadiene-styrene copolymers

1997 ◽  
Vol 9 (11) ◽  
pp. 877-879
Author(s):  
M. Dulce Geraldo ◽  
M. Irene Montenegro
Keyword(s):  
Acrylonitrile Butadiene Styrene ◽  
Styrene Copolymers ◽  
Butadiene Styrene

FURTHER DEVELOPMENTS IN THE VISTEX METHOD FOR THE DETERMINATION OF THE INTRINSIC VISCOSITY OF HIGH POLYMERS

1949 ◽  
Vol 27b (7) ◽  
pp. 666-681 ◽  
Author(s):  
D. A. Henderson ◽  
N. R. Legge
Keyword(s):  
Molecular Weight ◽  
Intrinsic Viscosity ◽  
Average Molecular Weight ◽  
Solvent Mixture ◽  
Gel Point ◽  
Styrene Copolymers ◽  
A Value ◽  
Pure Solvent ◽  
Butadiene Styrene

The intrinsic "vistex" viscosities of several series of butadiene–styrene copolymers of varying conversion and average molecular weight, dissolved directly from the latex in the vistex solvent mixture (toluene–isopropanol, 80/20 by volume), have been investigated and compared with the intrinsic viscosities of the corresponding coagulated, dried polymers dissolved in toluene. The intrinsic viscosity in toluene, [η]T, is related to the intrinsic vistex viscosity, [η]V, in toluene–isopropanol by the equation:—[Formula: see text]Hence, viscosity average molecular weight may be calculated from vistex measurements.A further development of the method has shown that, once the latex is dissolved in the vistex solvent, the solution may be diluted, within certain denned limits, by the addition of pure solvent (toluene) to obtain the several levels of concentration of polymer required for the determination of intrinsic viscosity. It is then possible, by extrapolation to zero concentration of polymer, to obtain a value for the intrinsic viscosity that is equal to the conventional intrinsic viscosity of the polymer in pure solvent after coagulation and drying under very mild conditions. The viscosity characteristics of butadiene–styrene copolymers of varying conversion appear to be represented, at conversions below the gel point, by the equation,[Formula: see text]where β′ and n are constants of the order of 0.25 and 1 for solutions in toluene and 0.1 and 2.5 respectively for vistex solutions. Distinct changes in β and/or n have been found at conversions in the region of and beyond the gel point.

Spectrophotometric Determination of the Styrene Content of Butadiene-Styrene Copolymers

1946 ◽  
Vol 19 (4) ◽  
pp. 1077-1084 ◽  
Author(s):  
E. J. Meehan
Keyword(s):  
Molecular Weight ◽  
Spectrophotometric Determination ◽  
Extinction Coefficient ◽  
Ultraviolet Spectrophotometry ◽  
Relative Precision ◽  
Specific Extinction Coefficient ◽  
Styrene Copolymers ◽  
Styrene Content ◽  
Butadiene Styrene

Abstract The ultraviolet absorption of polystyrene, with maximum absorption at 262 mµ, is due to the presence of phenyl residues in the polymer. The specific extinction coefficient is constant, i.e., independent of the molecular weight of the polymer. This shows that the extinction of the phenyl residues is additive. On the basis of this fact, it is shown that the styrene content of a butadiene-styrene copolymer (such as GR-S rubber) can be determined by ultraviolet spectrophotometry. The relative precision of the determination is about 1 per cent, the probable relative accuracy is about 3 per cent.

Comparison of Ultraviolet Absorption and Chlorine Analysis Methods for Composition of Butadiene-p-Chlorostyrene Copolymers

1947 ◽  
Vol 20 (1) ◽  
pp. 313-314 ◽  
Author(s):  
E. J. Meehan ◽  
T. D. Parks ◽  
H. A. Laitinen
Keyword(s):  
Extinction Coefficient ◽  
Spectrophotometric Method ◽  
Wave Length ◽  
Chloride Ion ◽  
Amperometric Titration ◽  
Specific Extinction Coefficient ◽  
Styrene Copolymers ◽  
Composition Determination ◽  
Butadiene Styrene

Abstract The percentage of chlorine in a copolymer containing chlorostyrene can be determined by amperometric titration of the chloride ion present after sodium fusion of the polymer. Since the percentage of chlorine is proportional to the percentage of chlorostyrene, the composition of a butadiene—chlorostyrene copolymer may be determined directly. This absolute method of composition determination affords a means of checking the ultraviolet spectrophotometric method which has been proposed for the determination of the composition of butadiene—styrene copolymers. In the application of the spectrophotometric method it is assumed that the specific extinction coefficient of the copolymer varies linearly with the percentage of styrene between the values of the same wave length for polybutadiene and polystyrene. The spectrophotometric measurements are made at 260.0 mµ or at 269.5 mµ for copolymers of butadiene with styrene or with p-chlorostyrene, respectively.

Colorimetric Determination of Phenyl-2-Naphthylamine in Rubber

1956 ◽  
Vol 29 (2) ◽  
pp. 647-650 ◽  
Author(s):  
P. Menšík ◽  
D. Broulík
Keyword(s):  
Colorimetric Method ◽  
Coupling Reaction ◽  
Colorimetric Determination ◽  
Styrene Copolymers ◽  
Butadiene Styrene

Abstract A colorimetric method was worked out for the determination of the amount of phenyl-2-naphthylamine in butadiene-styrene copolymers based on the coupling reaction of phenyl-2-naphthylamine with diazotized p-nitroaniline. The method was found practically applicable. It is accurate, and the procedure is simple.

Quantitative determination of longitudinal and transverse cross-relaxation rates

1999 ◽  
Vol 96 (9/10) ◽  
pp. 1608-1615
Author(s):  
T. E. Malliavin ◽  
H. Desvaux ◽  
M. A. Delsuc
Keyword(s):  
Quantitative Determination ◽  
Cross Relaxation ◽  
Relaxation Rates
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