Selectivity of Poly(styrene-divinylbenzene) Columns

Some additional data about properties and applicability of a styrene-divinylbenzene polymer catalyst containing acidic and redox functional groups are reported. It is shown that the catalysts of this type can be prepared reproducibly and exhibit catalytic properties comparable to the properties of noble metal catalysts.

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Small angle X-ray scattering study of porosity variation in a styrene-divinylbenzene copolymer

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19811675 ◽

1981 ◽

Vol 46 (7) ◽

pp. 1675-1681 ◽

Cited By ~ 13

Author(s):

Josef Baldrian ◽

Božena N. Kolarz ◽

Henrik Galina

Keyword(s):

Small Angle ◽

Structural Parameters ◽

Two Phase ◽

X Ray ◽

Porosity Variation ◽

Swelling Agent ◽

X Ray Scattering ◽

Styrene Divinylbenzene ◽

Ray Scattering

Porosity variations induced by swelling agent exchange were studied in a styrene-divinylbenzene copolymer. Standard methods were used in the characterization of copolymer porosity in the dry state and the results were compared with related structural parameters derived from small angle X-ray scattering (SAXS) measurements as developed for the characterization of two-phase systems. The SAXS method was also used for porosity determination in swollen samples. The differences in the porosity of dry samples were found to be an effect of the drying process, while in the swollen state the sample swells and deswells isotropically.

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Reesterification of ethyl acetate by propanol catalysed by glycidyl methacrylate copolymers containing sulphonic acid groups

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19811941 ◽

1981 ◽

Vol 46 (8) ◽

pp. 1941-1946 ◽

Cited By ~ 2

Author(s):

Karel Setínek

Keyword(s):

Liquid Phase ◽

Ethyl Acetate ◽

Kinetic Study ◽

Gas Phase ◽

Nonlinear Regression ◽

Kinetic Data ◽

Glycidyl Methacrylate ◽

Kinetic Equations ◽

Methacrylate Copolymers ◽

Styrene Divinylbenzene

A series of differently crosslinked macroporous 2,3-epoxypropyl methacrylate-ethylenedimethacrylate copolymers with chemically bonded propylsulphonic acid groups were used as catalysts for the kinetic study of reesterification of ethyl acetate by n-propanol in the liquid phase at 52 °C and in the gas phase at 90 °C. Analysis of kinetic data by the method of nonlinear regression for a series of equations of the Langmuir-Hinshelwood type showed that kinetic equations which describe best the course of the reaction are the same as for the earlier studied sulphonated macroporous styrene-divinylbenzene copolymers. Compared types of catalysts differ, however, in the dependence of their activity on the degree of crosslinking of the copolymer used.

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Polymer oxidation catalyst containing acidic functional groups

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19811237 ◽

1981 ◽

Vol 46 (5) ◽

pp. 1237-1247

Author(s):

Zdeněk Prokop ◽

Karel Setínek

Keyword(s):

Functional Groups ◽

Elevated Temperatures ◽

Redox Properties ◽

Oxidation Catalyst ◽

Carbon Clusters ◽

Oxidation Activity ◽

Redox Sites ◽

Styrene Divinylbenzene ◽

Proportional Decrease ◽

Polymer Oxidation

The catalyst containing redox sites in addition to acid functional groups was prepared by sulphonation of a macroporous chloromethylated styrene-divinylbenzene copolymer with concentrated sulphuric acid at elevated temperatures. Its activity was tested for the oxidation of 2-propanol by molecular oxygen at 120 °C and was found to be comparable to that of the iridium on carbon catalyst.Neutralisation of acid functional groups by alkali metal led to proportional decrease in the oxidation activity. The results of EPR spectroscopic study of these catalysts show that the redox properties of the polymer are caused by carbon clusters which are capable of electron exchange.

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The effect of partial exchange of sulphonated macroporous styrene-divinylbenzene copolymers for different ions on their catalytic activity

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19812354 ◽

1981 ◽

Vol 46 (10) ◽

pp. 2354-2363 ◽

Cited By ~ 4

Author(s):

Svatomír Kmošták ◽

Karel Setínek

Keyword(s):

Catalytic Activity ◽

Transition Metal ◽

Metal Ions ◽

Gas Phase ◽

Transition Metal Ions ◽

Exchange Capacity ◽

Total Exchange Capacity ◽

Styrene Divinylbenzene ◽

Na Ions ◽

Type Of Transition

The catalytic activity of sulphonated macroporous styrene-divinylbenzene copolymers, the exchange capacity of which was neutralized from 30, 50 and 80% by Fe(III) ions and from 30% by Na ions and that of Wofatit Y-37 ion exchanger neutralized from 10% of its total exchange capacity by several transition metal ions and by sodium has been studied in isomerisation of cyclohexene and dehydration of 1-propanol in the gas phase at 130 °C. It was demonstrated that in both reactions transition metal ions exhibit additional effect to the expected neutralization of the polymer acid groups. In the case of cyclohexene isomerization, this effect depends on the degree of crosslinking of polymer mass of the catalyst. Such dependence has not been, however, observed in dehydration of 1-propanol. The type of transition metal ions did not exhibit any significant effect on the catalytic activity of the polymer catalysts studied.

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Polymer structure and catalytic activity of ion exchangers

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19811577 ◽

1981 ◽

Vol 46 (7) ◽

pp. 1577-1587 ◽

Cited By ~ 8

Author(s):

Karel Jeřábek

Keyword(s):

Catalytic Activity ◽

Ethyl Acetate ◽

Active Sites ◽

Crosslinking Agent ◽

Reaction Medium ◽

Polymer Structure ◽

Local Concentration ◽

Ion Exchangers ◽

Styrene Divinylbenzene ◽

Kinetics Of

Catalytic activity of ion exchangers prepared by partial sulphonation of styrene-divinylbenzene copolymers in reesterifications of ethyl acetate by methanol and propanol, hydrolysis of ethyl acetate and in synthesis of bisphenol A has been compared with data on polymer structure of these catalysts and with distribution of the crosslinking agent, divinylbenzene, calculated from literature data on kinetics of copolymerisation of styrene with divinylbenzene. It was found that the polymer structure of ion exchangers influences catalytic activity predominantly by changing the local concentration of acid active sites. The results obtained indicated that the effect of transport phenomena on the rate of catalytic reactions does not depend on the degree of swelling of the ion exchangers in reaction medium but it is mainly dependent on the relative affinity of reaction components to the acid groups or to the polymer skeleton.

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