2013
Synthesis of Organosilicate Gels by Non-Hydrolytic Reactions of Silicon Acetate
PINKAS, Jiří, Martin KEJÍK, Zdeněk MORAVEC a Craig BARNESZákladní údaje
Originální název
Synthesis of Organosilicate Gels by Non-Hydrolytic Reactions of Silicon Acetate
Autoři
PINKAS, Jiří (203 Česká republika, garant, domácí), Martin KEJÍK (203 Česká republika, domácí), Zdeněk MORAVEC (203 Česká republika, domácí) a Craig BARNES (840 Spojené státy)
Vydání
XVII International Sol-Gel Conference, Madrid, Spain, 2013
Další údaje
Jazyk
angličtina
Typ výsledku
Konferenční abstrakt
Obor
10402 Inorganic and nuclear chemistry
Stát vydavatele
Španělsko
Utajení
není předmětem státního či obchodního tajemství
Kód RIV
RIV/00216224:14740/13:00069404
Organizační jednotka
Středoevropský technologický institut
Klíčová slova anglicky
Organosilicates; Non-Hydrolytic; Sol-Gel; Silicon Acetate
Změněno: 11. 10. 2013 16:55, prof. RNDr. Jiří Pinkas, Ph.D.
Anotace
V originále
A non-hydrolytic sol-gel synthesis of new mesoporous organosilicate materials containing phenolic and bisphenolic structural motifs was developed. Xerogels are formed in polycondensation reactions of multifunctional phenols, such as hydroquinone, 4,4-dihydroxybiphenyl, bisphenol A, and phloroglucinol with silicon acetate in polar ether solvent. Acetic acid was identified as an elimination reaction byproduct. Xerogels were obtained upon drying in vacuo and the produced materials contain residual acetoxy and phenolic hydroxyl groups allowing for later grafting and surface modification. An impact of employed spacer molecule and reaction conditions on the degree of condensation and xerogel porosity was studied. Condensation degree was established by gravimetric techniques and appears to be independent of reaction temperature but strongly depends on the nature of the spacer molecule. Hydroquinone provided gels with the highest value of 91%. Surface area of xerogels depends both on reaction temperature and the phenol ligand. A higher reaction temperature leads to a larger surface area; phloroglucinol providing gel with up to 790 m2/g of surface. Additionally a study of grafting organic groups on the gel surface by the reactions with alcohols and phenols and anchoring of aluminum species by treating the gels with compounds such as AlR3 and AlX3 was performed. All the prepared xerogels and modified materials were characterized by elemental analyses, solid-state 13C, 27Al, and 29Si NMR, IR spectroscopy, surface area analysis, thermal analysis TG/DSC, and XRD.
Návaznosti
| ED1.1.00/02.0068, projekt VaV |
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| LH11028, projekt VaV |
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