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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Spectral and thermal characterization of halogen-bonded novel crystalline oligo(p-bromoacetophenone formaldehyde)
Narendra Pal Singh Chauhan1, Masoud Mozafari, Rakshit Ameta
1Department of Chemistry, Bhupal Nobles Post Graduate (B.N.P.G.) College , Udaipur 313001, Rajasthan, India.
Abstract:
A novel oligomer p-bromoacetophenone-formaldehyde (OPBAF) was prepared by condensation polymerization in the presence of an acid as catalyst. It was characterized by FT-IR, NMR, pyrolysis GC/MS, XRD, GPC, and TG-DTG. The crystallographic parameters and space group for hexagonal OPBAF were a = b = 2.0810 Å and c = 9.2340 Å and P3̅m1, respectively. The degradation activation energy of the oligomer was studied by the Kissinger method. The kinetic parameters were also obtained. Halogen bonding interactions in the crystalline oligomers are identified between halogen···carbonyl and halogen···halogen. Little correlation was found in the halogen bonding motifs exhibited as a function of bromine present in this oligomer, and a unique bifurcated Br···Br/Br···O═C halogen bonding synthon was identified. This newly developed oligomer may be used as an interesting material for the development of 3D-designed structural products.
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