Differences in catalytic activity of poly(vinylamine) introduced on surface of mesoporous SBA-15 by grafting from and grafting onto methods in Knoevenagel condensation

2015
journal article
article
13
dc.abstract.enVarious amounts of poly(vinylamine) (PVAm) were deposited on the surface of SBA-15 mesoporous silicas, prefunctionalized with suitable organosilanes, by two different grafting techniques: "grafting from" and "grafting onto". In the grafting from route, the radical copolymerization between the vinyl-modified SBA-15 and N-vinylformamide, followed by acid hydrolysis and neutralization, was performed. The grafting onto pathway consisted of the reaction of preprepared PVAm chains with epoxide functionalities present on the silica surface. Diffuse reflectance Fourier transform spectroscopy confirmed the formation of covalent and hydrogen bonds between PVAm and the prefunctionalized SBA-15 surface. Low-temperature $N_{2}$ adsorption and X-ray photoelectron spectroscopy allowed the observation of differences in the distribution of formed PVAm in the pore system of SBA-15. A higher efficiency of polymer deposition and its higher dispersion were achieved using the grafting from method. Furthermore, X-ray diffraction and transmission electron microscopy confirmed the stability of the hexagonal SBA-15 structure during all modification steps. The number of accessible $NH_{2}$ surface species, considered as active sites, appeared to be a crucial parameter influencing the catalytic activity of the synthesized hybrid materials in the Knoevenagel condensation of benzaldehyde and ethyl cyanoacetate.pl
dc.affiliationWydział Chemii : Zakład Technologii Chemicznejpl
dc.affiliationWydział Biologii i Nauk o Ziemi : Instytut Nauk Geologicznychpl
dc.contributor.authorWach, Anna - 126105 pl
dc.contributor.authorDrozdek, Marek - 127763 pl
dc.contributor.authorDudek, Barbara - 127798 pl
dc.contributor.authorŁątka, Piotr - 183982 pl
dc.contributor.authorBiazik, Martapl
dc.contributor.authorMichalik, Marek - 130514 pl
dc.contributor.authorKuśtrowski, Piotr - 129800 pl
dc.date.accessioned2015-12-02T10:38:43Z
dc.date.available2015-12-02T10:38:43Z
dc.date.issued2015pl
dc.description.admin[AB] Biazik, Marta 50000141pl
dc.description.number34pl
dc.description.physical19954-19966pl
dc.description.volume119pl
dc.identifier.doi10.1021/acs.jpcc.5b05868pl
dc.identifier.eissn1932-7455pl
dc.identifier.issn1932-7447pl
dc.identifier.urihttp://ruj.uj.edu.pl/xmlui/handle/item/17395
dc.languageengpl
dc.language.containerengpl
dc.rights.licencebez licencji
dc.subtypeArticlepl
dc.titleDifferences in catalytic activity of poly(vinylamine) introduced on surface of mesoporous SBA-15 by grafting from and grafting onto methods in Knoevenagel condensationpl
dc.title.journalThe Journal of Physical Chemistry. Cpl
dc.typeJournalArticlepl
dspace.entity.typePublication
dc.abstract.enpl
Various amounts of poly(vinylamine) (PVAm) were deposited on the surface of SBA-15 mesoporous silicas, prefunctionalized with suitable organosilanes, by two different grafting techniques: "grafting from" and "grafting onto". In the grafting from route, the radical copolymerization between the vinyl-modified SBA-15 and N-vinylformamide, followed by acid hydrolysis and neutralization, was performed. The grafting onto pathway consisted of the reaction of preprepared PVAm chains with epoxide functionalities present on the silica surface. Diffuse reflectance Fourier transform spectroscopy confirmed the formation of covalent and hydrogen bonds between PVAm and the prefunctionalized SBA-15 surface. Low-temperature $N_{2}$ adsorption and X-ray photoelectron spectroscopy allowed the observation of differences in the distribution of formed PVAm in the pore system of SBA-15. A higher efficiency of polymer deposition and its higher dispersion were achieved using the grafting from method. Furthermore, X-ray diffraction and transmission electron microscopy confirmed the stability of the hexagonal SBA-15 structure during all modification steps. The number of accessible $NH_{2}$ surface species, considered as active sites, appeared to be a crucial parameter influencing the catalytic activity of the synthesized hybrid materials in the Knoevenagel condensation of benzaldehyde and ethyl cyanoacetate.
dc.affiliationpl
Wydział Chemii : Zakład Technologii Chemicznej
dc.affiliationpl
Wydział Biologii i Nauk o Ziemi : Instytut Nauk Geologicznych
dc.contributor.authorpl
Wach, Anna - 126105
dc.contributor.authorpl
Drozdek, Marek - 127763
dc.contributor.authorpl
Dudek, Barbara - 127798
dc.contributor.authorpl
Łątka, Piotr - 183982
dc.contributor.authorpl
Biazik, Marta
dc.contributor.authorpl
Michalik, Marek - 130514
dc.contributor.authorpl
Kuśtrowski, Piotr - 129800
dc.date.accessioned
2015-12-02T10:38:43Z
dc.date.available
2015-12-02T10:38:43Z
dc.date.issuedpl
2015
dc.description.adminpl
[AB] Biazik, Marta 50000141
dc.description.numberpl
34
dc.description.physicalpl
19954-19966
dc.description.volumepl
119
dc.identifier.doipl
10.1021/acs.jpcc.5b05868
dc.identifier.eissnpl
1932-7455
dc.identifier.issnpl
1932-7447
dc.identifier.uri
http://ruj.uj.edu.pl/xmlui/handle/item/17395
dc.languagepl
eng
dc.language.containerpl
eng
dc.rights.licence
bez licencji
dc.subtypepl
Article
dc.titlepl
Differences in catalytic activity of poly(vinylamine) introduced on surface of mesoporous SBA-15 by grafting from and grafting onto methods in Knoevenagel condensation
dc.title.journalpl
The Journal of Physical Chemistry. C
dc.typepl
JournalArticle
dspace.entity.type
Publication

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