This document summarizes the synthesis and characterization of a sulfur-functional layered silicate (SMMT) for use in nanocomposite elastomers. Sodium montmorillonite (MMT) was purified and intercalated with CTAB. It was then functionalized with a sulfur-containing silane coupling agent (Si69) to produce SMMT. SMMT was successfully grafted with squalene as evidenced by FTIR, XRD, and TGA results. The grafted SMMT showed potential for compatibility with elastomers due to the covalent bonding between SMMT and squalene via Si69.
The Imaging Laboratory of the Jagiellonian Center of Innovation offers a broad range of services within the scope of surface analysis based mainly on Raman spectroscopy and electron microscopy.
Συνέντευξη στο Πρώτο Θέμα: Μέσα σε 18 μήνες ξεκίνησαν νέες επενδύσεις 20 δισ. €Notis Mitarachi
Ο Υφυπουργός Ανάπτυξης & Ανταγωνιστικότητας, κ. Νότης Μηταράκης μιλά στο Πρώτο Θέμα και στο B.S. για τη μεγάλη προσπάθεια προσέλκυσης επενδύσεων στην Ελλάδα, ενώ υποστηρίζει ότι οι θυσίες του λαού όλα αυτά τα χρόνια έπιασαν τόπο και ότι η χώρα μπαίνει πλέον στη μετά μνημόνιο εποχή.
The Imaging Laboratory of the Jagiellonian Center of Innovation offers a broad range of services within the scope of surface analysis based mainly on Raman spectroscopy and electron microscopy.
Συνέντευξη στο Πρώτο Θέμα: Μέσα σε 18 μήνες ξεκίνησαν νέες επενδύσεις 20 δισ. €Notis Mitarachi
Ο Υφυπουργός Ανάπτυξης & Ανταγωνιστικότητας, κ. Νότης Μηταράκης μιλά στο Πρώτο Θέμα και στο B.S. για τη μεγάλη προσπάθεια προσέλκυσης επενδύσεων στην Ελλάδα, ενώ υποστηρίζει ότι οι θυσίες του λαού όλα αυτά τα χρόνια έπιασαν τόπο και ότι η χώρα μπαίνει πλέον στη μετά μνημόνιο εποχή.
adsorption of methylene blue onto xanthogenated modified chitosan microbeadsSiti Nadzifah Ghazali
Methylene Blue (MB) is thiazine dyes that widely use to color product in many industry such as textile, printing, leather, cosmetic and paper. Xanthogenated-Modified Chitosan Microbeads (XMCM) is use to observe the new alternative adsorbent in removing MB from water body through adsorption process. The interactions between MB and functional group in XMCM were confirmed by Fourier Transform Infrared (FT-IR) spectra. Several parameters that influence adsorption ability such as the effect of adsorbent dosage of XMCM and the effect of initial pH of MB aqueous solution were studied. This study were done at optimum condition which is at pH 4 of initial pH of MB solution, 0.01 g of initial XMCM dosage, 6 hours stirring time and temperature of (30 ± 2 ℃). The adsorption data fit well Langmuir model more than Freundlich model. Based on Langmuir model, the maximum monolayer adsorption capacity of MB was 21.62 mg g-1 which indicated that XMCM can be a new alternative adsorbent for removing MB.
adsorption of methylene blue onto xanthogenated modified chitosan microbeadsSiti Nadzifah Ghazali
Methylene Blue (MB) is thiazine dyes that widely use to color product in many industry such as textile, printing, leather, cosmetic and paper. Xanthogenated-Modified Chitosan Microbeads (XMCM) is use to observe the new alternative adsorbent in removing MB from water body through adsorption process. The interactions between MB and functional group in XMCM were confirmed by Fourier Transform Infrared (FT-IR) spectra. Several parameters that influence adsorption ability such as the effect of adsorbent dosage of XMCM and the effect of initial pH of MB aqueous solution were studied. This study were done at optimum condition which is at pH 4 of initial pH of MB solution, 0.01 g of initial XMCM dosage, 6 hours stirring time and temperature of (30 ± 2 ℃). The adsorption data fit well Langmuir model more than Freundlich model. Based on Langmuir model, the maximum monolayer adsorption capacity of MB was 21.62 mg g-1 which indicated that XMCM can be a new alternative adsorbent for removing MB.
GC workshop at the National Symposium for Advances in Pharmaceutical Analysis (APAT 2013). St Peter's Institute of Pharmaceutical Sciences, Hanamkonda, Warangal, AP, India.
1. SYNTHESIS AND CHARACTERIZATION OF SULFUR-FUNCTIONAL LAYERED
SILICATE FOR USE IN NANOCOMPOSITE ELASTOMERS
Randy Fang, Shigeng Li, and Dr. Harry Ploehn
Department of Chemical Engineering,
University of South Carolina, Columbia, SC 29208
Introduction
Experiments
Results Elemental Analysis
C% H% N% S%
Moles of
CTAB/g of MMT
Moles of
Si69/g of MMT
CTAB-MMT 19.55 4.29 1.27 0 1.2×10-3
0
SMMT 17.48 3.76 1.06 1.81 1.0×10-3
1.9×10-4
Squalene Grafting Reactions
Conclusions
Acknowledgements
Objective
Prepare clean Na-MMT and functionalize it with sulfur-containing silane coupling agent
(Si69) to produce sulfur-functional MMT (SMMT).
Assess the potential compatibility of SMMT with elastomers by studying the reaction of
SMMT with squalene, a small-molecule model compound resembling natural rubber.
Both industry and academia are interested in elastomer nanocomposites – elastomeric
polymers containing inorganic nanoparticles such as layered silicates.
Small amounts of inorganic layered silicate particles could enhance the properties of
elastomers, such as mechanical strength and toughness, thermal stability, and gas barrier.
Based on our previous studies, clean sodium montmorillonite (Na-MMT) can be fully
exfoliated in water. However, Na-MMT is not naturally compatible with elastomers.
Clean MMT: Na-MMT was dispersed in water to fully exfoliate into
single platelets and remove any impurities by centrifugation.
SMMT: Si69 was added to react with the edge –OH groups of MMT.
SMMT-Squalene: Squalene, an analog of natural rubber, was reacted with SMMT.
XRD patterns of MMT, CTAB-MMT,
and SMMT:
Low angle peak indicates inter-layer
spacing (d-spacing)
CTAB-MMT d-spacing of 1.94 nm
indicates expansion of relative to MMT
(1.2 nm)
SMMT d-spacing of 1.86 nm is almost
the same as that of CTAB-MMT
Results consistent with SMMT
containing interlayer CTAB and edge-
grafted Si69
TGA of pure MMT
TGA of CTAB-MMT TGA of SMMT
FTIR spectra of clean MMT, CTAB,
CTAB-MMT, SMMT, SMMT-
Squalene:
CTAB-MMT and SMMT spectra include
peaks indicating presence of CTAB
SMMT spectrum does not show unique
peaks from Si69 – hidden by CTAB
peaks
Squalene-SMMT spectrum shows
unique peaks indicating squalene
grafting
MMT structure
110°C, 48hr,
N2 atmosphere
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
Si69/toluene
OH
OH
OH
OH
OH
Squalene, 150°C, 24hr,
N2 atmosphere
OH
OH
0.9 nm
0.2 nm
60°C, 24hr
Na+
Na+ CTAB/H2O
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
OH
TGA of Squalene-SMMTTGA of Squalene-CTAB-MMT
University of South Carolina
South Carolina Governor's School for Science and Mathematics
Dr. Harry Ploehn
Shigeng Li
CTAB intercalated and expanded the interlayer of MMT
The edges of MMT were functionalized with Si69 to produce SMMT
Squalene successfully grafted onto SMMT via the covalent bond with Si69
TGA suggests some squalene may intercalate into the SMMT interlayer space, leading to the
increase in d-spacing of squalene-SMMT
TGA data for MMT, CTAB-MMT, SMMT:
MMT: 14.6% loss of water (hydrophilic), 5.7%
dehydroxylation loss
CTAB-MMT: 2% water (hydrophobic), 24% loss from
CTAB, and ~5% dehydroxylation loss. Two peaks:
weakly and strongly adsorbed CTAB
SMMT: 2% water, 27% loss from CTAB and Si69 (no
dehydrox. loss). Organic weight loss may be greater
than in CTAB-MMT due to Si69. Peak shift perhaps due
to presence of Si69.
Nitrogen results: 15-20% decrease in CTAB content after Si69 grafting
Sulfur results: SMMT definitely contains sulfur: about 1:5 ratio of Si69 to CTAB in SMMT
XRD patterns of squalene-CTAB-
MMT and squalene-SMMT:
Squalene-CTAB-MMT control sample
shows d-spacing decrease from 1.94 to
1.8 nm, possibly indicating some CTAB
loss
Squalene-SMMT sample shows d-
spacing increase from 1.86 to 2.1 nm,
due to edge and (possibly) interlayer
squalene grafting
TGA data for squalene-CTAB-MMT and squalene-SMMT:
Squalene-CTAB-MMT: 2% water, 5% dehydrox. loss, and 26.5% loss from CTAB and
squalene. Possibly some squalene intercalation into CTAB-MMT
Squalene-SMMT: 2% water, 45% loss from CTAB, Si69, squalene. Overall weight loss much
larger, presumably due to grafting of squalene onto SMMT.
Fourier-Transform Infrared Spectroscopy (FTIR)
Thermogravimetric Analysis (TGA)
X-Ray Diffraction (XRD)
CTAB-MMT: CTAB was added to expand MMT’s interlayer and make it
more hydrophobic.