Phospholipids chiral at phosphorus. Characterization of the subgel phase of thiophosphatidylcholines by use of x-ray diffraction, phosphorus-31 nuclear magnetic resonance, and Fourier transform infrared spectroscopy

Biochemistry ◽  
1988 ◽  
Vol 27 (13) ◽  
pp. 4625-4631 ◽  
Author(s):  
Harry E. Sarvis ◽  
William Loffredo ◽  
Richard A. Dluhy ◽  
Lars Hernqvist ◽  
Daniel A. Wisner ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Magnetic Resonance ◽  
Fourier Transform Infrared Spectroscopy ◽  
Fourier Transform Infrared ◽  
X Ray Diffraction ◽  
X Ray ◽  
Subgel Phase

Synthesis and Characterization of Novel Organomodified Nanoclays for Application in Dental Materials

2019 ◽  
Vol >15 (5) ◽  
pp. 512-524 ◽  
Author(s):  
Alexandros K. Nikolaidis ◽  
Elisabeth A. Koulaouzidou ◽  
Dimitris S. Achilias
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Thermogravimetric Analysis ◽  
Fourier Transform Infrared Spectroscopy ◽  
Quaternary Ammonium ◽  
Fourier Transform Infrared ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray

Background: Nanoclays incorporated in dental resins have been previously investigated. However, limited reports are associated with nanoclays that exhibit high functionality. Objective: The aim of this study was the targeted synthesis and characterization of organomodified nanoclays with methacrylic groups suitable for incorporation in dental nanocomposite resins. Methods: Quaternary ammonium methacrylates were synthesized and characterized by means of proton nuclear magnetic resonance and Fourier-transform infrared spectroscopy. Consequently, they were inserted into the interlayer space of nanoclay through a cation exchange reaction, while silane was also used for simultaneous surface modification. The produced organomodified nanoclays were characterized by means of X-ray diffraction, Fourier-transform infrared spectroscopy and thermogravimetric analysis. Results: Fourier-transform infrared spectra confirmed the successful synthesis of the quaternary ammonium methacrylates. X-ray diffraction analysis showed that organoclays exhibited higher d001- values (up to 1.78 nm) compared to raw nanoclay (1.37 nm), indicating an accomplished intercalation in each case. X-ray diffraction spectra mainly disclosed the presence of methacrylic functional groups in all nanoclays. Thermogravimetric analysis curves verified the different thermal stability of organoclays due to the diversity of their organic modifiers. Conclusion: The experimental results showed that nanoclay was successfully modified with ammonium methacrylates and silane. Τhe combination of X-ray diffraction and thermogravimetric analysis data revealed a high degree of intercalation and methacrylated organic loading as well. These phenomena may favor a good dispersion and high polymerization degree of nanoclays with dental resin monomers, rendering them potentially useful materials for the development of advanced dental nanocomposites resins.

Preparation and characterization of poly(tetramethyl-p-phenylenediamine)/clay hybrids via intercalative polymerization

2003 ◽  
Vol 18 (2) ◽  
pp. 482-486 ◽  
Author(s):  
Guangming Chen ◽  
Nobuo Iyi ◽  
Taketoshi Fujita
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Thermal Behavior ◽  
Fourier Transform Infrared Spectroscopy ◽  
Interlayer Space ◽  
X Ray Diffraction ◽  
X Ray ◽  
Noncovalent Bonding ◽  
Intercalative Polymerization

New noncovalent bonding polymer/clay hybrids were prepared, including the polymer poly(tetramethyl-p-phenylenediamine) (poly-TMPD). Polymerization occurred in the interlayer space of clay mineral successively after intercalation of monomers. Two types of clay minerals with different surface properties—a hydrophilic lithium fluorotaeniolite (TN) and four kinds of organophilic fluorotaeniolites (org-TNs)—were used as the hosts. Powder x-ray diffraction results showed an increase of 0.7–1.0 nm in the basal spacings, indicating the formation of poly–TMPD in the interlayer space of the hosts. Intercalative polymerization was also supported by Fourier transform infrared spectroscopy. The orientation of the poly-TMPD and thermal behavior were also discussed.

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