Characterization of a Polyanhydride Series by Ftir

1993 ◽  
Vol 331 ◽  
Author(s):  
Mark R. Kreitz ◽  
Kathleen J. Pekarek ◽  
Edith Mathiowitz

AbstractUsing Fourier-transform infrared (FTIR) spectroscopy we have characterized a polyanhydride copolymer series composed of various ratios of the diacids 1,3-bis(p -carboxyphenoxy)propane (CPP) and sebacic acid (SA). Typical peaks corresponding to the aliphatic-aliphatic (SA-SA), aromatic-aliphatic (CPP-SA), and aromatic-aromatic (CPP-CPP) diads were found in the 1820- 1710 cm−1 wavenumber range. Further peaks corresponding to the SA-SA diads were identified in the fingerprint region at 1382, 1360, 1307, and 1286 cm−1. These peak characterizations facilitate identification of bond distribution in the CPP-SA copolymer as well as other polyanhydride copolymers, and correlate well with previously presented information obtained with nuclear magnetic resonance (NMR) spectroscopy and X-ray powder diffraction.

2015 ◽  
Vol 12 (2) ◽  
pp. 13
Author(s):  
Muhamad Faridz Osman ◽  
Karimah Kassim

The coordination complexes of Co(II) and Zn(II) with Schiff bases derived from o-phenylenediamine and substituted 2-hydroxybenzaldehyde were prepared All compounds were characterized by Fourier transform infrared (FTIR) spectroscopy and Nuclear magnetic resonance (NMR) spectroscopy elemental analyzers. They were analyzed using impedance spectroscopy in the frequency range of 100Hz-1 MHz. LI and L2 showed higher conductivity compared to their metal complexes, which had values of 1.3 7 x 10-7 and 6.13 x 10-8 S/cm respectively. 


Clay Minerals ◽  
1986 ◽  
Vol 21 (5) ◽  
pp. 879-897 ◽  
Author(s):  
M. A. Wilson ◽  
S. A. McCarthy ◽  
P. M. Fredericks

AbstractThe structure of synthetic aluminosilicates prepared at pH 6 has been investigated by 29Si and 27Al high-resolution solid-state nuclear magnetic resonance (NMR) spectroscopy. Fourier transform infrared (FTIR) spectroscopy and electron microscopy have also been used to characterize the products. The amount of Si and Al in protoimogolite, disordered allophane and other structures has been measured. There is a fair correlation between the intensity of the 349 cm−1 band in the FTIR spectra and the proportion by weight of protoimogolite Si measured by NMR. It is shown that disordered allophanes have similar structures to those proposed by van Reeuwijk and de Villiers (Soil Sci. Soc. Am. Proc. 32 (1968) 238–240), i.e. octahedral Al surrounding a tetrahedral core. Moreover, it is clear that at high Al:Si ratios (⩾1:1), protoimogolite can compete with disordered allophane precursors for aluminum. The driving forces for formation of protoimogolite rather than allophane appear to be long range Al-Al repulsive forces through oxygen.


1993 ◽  
Vol 71 (11) ◽  
pp. 1821-1827 ◽  
Author(s):  
Tristram Chivers ◽  
Daniel D. Doxsee ◽  
Robert W. Hilts ◽  
Masood Parvez

The reaction of 1,5-Ph4P2N4S2Ph2 with [PtCl2CPEt3)]2 in chloroform at 60 °C produces the 1:1 adduct trans-PtCl2(PEt3)(Ph4P2N4S2Ph2) in which the platinum is attached to a nitrogen atom on the basis of 31P nmr spectroscopy. By contrast, the corresponding reactions of 1,5-Ph4P2N4Se2R2 (R = Me, Et, Ph) produce the 2:1 adducts [PtCl2(PEt3)]2(Ph4P2N4Se2R2) (7a, R = Me; 7b, R = Et; 7c, R = Ph) which have been characterized by 1H, 31P and 77Se nmr spectroscopy and, in the case of 7b, by X-ray crystallography. Crystals of 7b are monoclinic, space group C2/c, with a = 27.803(7) Å, b = 12.378(7) Å, c = 15.752(8) Å, β = 115.49(2)°, V = 4893(3) Å3, and Z = 4. The least-squares refinement with anisotropic thermal parameters for all non-hydrogen atoms converged at R = 0.037 and Rw = 0.022. The platinum centres in 7b are attached to distal nitrogen atoms of the disordered P2N4Se2 ring. The reaction of the six-membered ring Ph4P2N3SPh with [PtCl2(PEt3)]2 in dichloromethane at 23 °C occurs in a regiospecific manner to give the 1:1 adduct PtCl2(PEt3)(Ph4P2N3SPh) in which, on the basis of 31P nmr spectroscopy, the platinum is coordinated to a nitrogen atom between phosphorus and sulfur.


2007 ◽  
Vol 21 (3) ◽  
pp. 1548-1561 ◽  
Author(s):  
S. R. Kelemen ◽  
M. Afeworki ◽  
M. L. Gorbaty ◽  
M. Sansone ◽  
P. J. Kwiatek ◽  
...  

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