Synthesis of highly reactive polyisobutylene by catalytic chain transfer in hexanes at elevated temperatures; determination of the kinetic parameters

2017 ◽  
Vol 8 (18) ◽  
pp. 2852-2859 ◽  
Author(s):  
Tota Rajasekhar ◽  
Jack Emert ◽  
Rudolf Faust
Keyword(s):  
Kinetic Parameters ◽  
Rate Constants ◽  
Chain Transfer ◽  
Elevated Temperatures ◽  
Polymerization Rate ◽  
Carbenium Ions ◽  
Catalytic Chain Transfer ◽  
Highly Reactive Polyisobutylene ◽  
Increasing Temperature

The rate constants of activation/deactivation for dormant oxonium/active carbenium ions have been measured and related to the increasing polymerization rate with increasing temperature.

Kinetics and Modelling of Bulk and Solution Diallyl Terephthalate Polymerization

2006 ◽  
Vol 4 (1) ◽  
Author(s):  
Iztok Hace
Keyword(s):  
Kinetic Model ◽  
Kinetic Parameters ◽  
Rate Constants ◽  
Chain Transfer ◽  
Average Molecular Weight ◽  
Propagation Rate ◽  
Reaction Conditions ◽  
Diffusion Limitations ◽  
Kinetics Of ◽  
Dicyclohexyl Peroxydicarbonate

Free radical polymerization kinetics of diallyl terephthalate (DAT) in solution was investigated with two different peroxide initiators: dicyclohexyl peroxydicarbonate (CHPC) and benzoyl peroxide (BPO) in temperature range from 50°C to 110°C, where ortho-xylene was used as a solvent. Conversion points were measured using Fourier Transform Infrared (FTIR) measurements. Previously developed kinetic model for bulk DAT polymerization, was extended to solution DAT polymerization. The ratio of solvent chain - transfer rate constants to propagation rate constants of the polymerization system were found between 1.25 10-4 to 1.68 10-4 for various reaction conditions. They were obtained using the calculated initial polymerization rates and the number average molecular weight measurements made by GPC. The effect of different solvent fractions and initiator concentrations on the diffusion limitations were investigated. Only two kinetic parameters, kpd0 and ktd0 were obtained by fitting the kinetic model onto measured conversions for various reaction conditions at 0.2, 0.5 and 0.8 solvent fractions. Thus obtained kpd0 and ktd0 kinetic parameters were extrapolated to zero solvent fractions and from obtained values of kinetic parameters the conversion points for bulk DAT polymerization were calculated and compared to measured conversion points.

scholarly journals Synthesis and Determination of Polymerization Rate Constants of Glucose-Based Monomers

2011 ◽  
Vol 14 (5) ◽  
pp. 499-513 ◽  
Author(s):  
Shivaji K. Sharma ◽  
Grégory Durand ◽  
Bernard Pucci
Keyword(s):  
Rate Constants ◽  
Polymerization Rate

Determination of Kinetic Parameters using Linearly Increasing Temperature

1989 ◽  
Vol 54 (2) ◽  
pp. 446-450 ◽  
Author(s):  
J. W. RHIM ◽  
R. V. NUNES ◽  
V. A. JONES ◽  
K. R. SWARTZEL
Keyword(s):  
Kinetic Parameters ◽  
Increasing Temperature

scholarly journals Recent advances in catalytic chain transfer polymerization of isobutylene: a review

RSC Advances ◽  
2020 ◽  
Vol 10 (31) ◽  
pp. 18180-18191 ◽  
Author(s):  
Tota Rajasekhar ◽  
Gurmeet Singh ◽  
Gurpreet Singh Kapur ◽  
S. S. V. Ramakumar
Keyword(s):  
Chain Transfer ◽  
Lubricant Additives ◽  
Recent Advances ◽  
Catalytic Chain Transfer ◽  
Highly Reactive Polyisobutylene ◽  
Chain Transfer Polymerization

This review presents the development of highly reactive polyisobutylene (HRPIB), a major commercial intermediate toward fuel and lubricant additives.

Determination of the rate constants for chain transfer with the monomer and hydrogen in Ziegler-Natta polymerization

1976 ◽  
Vol 5 (4) ◽  
pp. 429-434 ◽  
Author(s):  
V. I. Zakharov ◽  
N. B. Chumaevskii ◽  
Z. K. Bulatova ◽  
G. D. Bukatov ◽  
Yu. I. Yermakov
Keyword(s):  
Rate Constants ◽  
Chain Transfer

scholarly journals Multi-channel IR sensor system for determination of oil degradation

2014 ◽  
Vol 3 (1) ◽  
pp. 121-132 ◽  
Author(s):  
T. Bley ◽  
E. Pignanelli ◽  
A. Schütze
Keyword(s):  
Elevated Temperatures ◽  
Oxidative Degradation ◽  
Sensor System ◽  
Oil Degradation ◽  
Motor Oil ◽  
Reference Channel ◽  
Measurement Results ◽  
Synthetic Motor ◽  
Increasing Temperature

Abstract. A miniaturized infrared (IR) multi-channel sensor system was realized to determine chemical oil degradation, e.g., oxidation, increasing water content. Different artificially aged oil samples (synthetic motor oil, mineral hydraulic oil and ester-based hydraulic fluid) were prepared by oxidative degradation at elevated temperatures or addition of water, and characteristic degradation features in the IR spectrum were detected using FTIR spectroscopy. In addition, the absorption behavior of water contaminated synthetic motor oil was analyzed with increasing temperature. To determine the influence of different degradation effects on the measurement results the sensor system was characterized with the various oil samples. The system uses a reference channel to suppress the effect of decreasing transmission over the entire spectrum caused, e.g., by increasing soot content in the oil or contamination of the optical path.

MEASUREMENT OF STEROID BINDING PROTEINS

1970 ◽  
Vol 65 (1_Suppl) ◽  
pp. S104-S121 ◽  
Author(s):  
E. E. Baulieu ◽  
J. P. Raynaud ◽  
E. Milgrom
Keyword(s):  
Kinetic Parameters ◽  
Binding Proteins ◽  
Binding Specificity ◽  
Binding Parameters ◽  
Target Organs ◽  
Biological Mixtures ◽  
Steroid Binding Proteins ◽  
Steroid Binding ◽  
Steroid Binding Protein

ABSTRACT A brief review of the characteristics of steroid binding proteins found in the plasma and in some target organs is presented, followed by some general remarks on binding »specificity« and binding parameters. Useful techniques for measuring binding parameters at equilibrium are reported, both those which keep the equilibrium intact and those which implicate its disruption. A concept is developed according to which the determination of a specific steroid binding protein is based on the »differential dissociation« of the several steroid binding complexes present in most biological mixtures. Methods which allow determination of the kinetic parameters of the binding systems are also presented. Various representations of the binding and therefore different modes of graphic representation and calculation are discussed, including the recent »proportion graph« method.

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