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Update on thermo-electrohydrodynamic model for electrospinning process
Published in A. K. Haghi, Lionello Pogliani, Francisco Torrens, Devrim Balköse, Omari V. Mukbaniani, Andrew G. Mercader, Applied Chemistry and Chemical Engineering, 2017
Shima. Maghsoodlou, S. Poreskandar
In polymers, intramolecular bonds are due to primary valence bonds (covalent) while the intermolecular attractions usually are due to secondary bonding forces. The intermolecular forces are opposed by thermal agitation, which induces vibration, rotation, and translation of a molecular system. Atomic vibrations exist at all temperature levels. The stability of the molecular system depends on the vibration energy of the chemical bonds. In polymers, thermal degradation occurs when the energy of vibration exceeds the primary bonding between atoms, while the transitional phenomena associated with the crystalline melting point, the glass transition temperature, and the polymer deformations are related to rotation and vibration of molecular chains (Fig. 12.2).11, 12
Introduction
Published in Armen S. Casparian, Gergely Sirokman, Ann O. Omollo, Rapid Review of Chemistry for the Life Sciences and Engineering, 2021
Armen S. Casparian, Gergely Sirokman, Ann O. Omollo
Chemical bonds between two or more atoms in a molecule are referred to as intramolecular forces. They are generally categorized as ionic, covalent, or metallic. These are the bonds that are broken and reformed during a chemical reaction. Significantly lower in strength are intermolecular forces. Intermolecular forces are generally attractive forces that exist between and among molecules of all shapes, sizes, and masses. They exist in the gaseous, liquid, and solid phases, as well as in the solution phase, where water is acting as the solvent to hydrate the solute.
Molecular engineering activity for chemistry teacher education: An interactive simulation on cellulose dissolution in ionic liquids
Published in Yuli Rahmawati, Peter Charles Taylor, Empowering Science and Mathematics for Global Competitiveness, 2019
A. Mudzakir, Hernani, T. Widhiyanti, L. Lokollo
Intermolecular force is the force of attraction between molecules, and intra-molecular force is the force between atoms in a molecule. Intramolecular forces affect the chemical properties of a substance, while intermolecular forces affect the physical properties of a substance. In general, intermolecular forces are weaker than intramolecular forces. The types of intermolecular forces are Van der Waals forces, ion-dipole forces, and hydrogen bonds (Jesperson & Brady, 2012; Chang & Overby, 2011).
Molecular recognition of isovanillin crosslinked carrageenan biocomposite for drug delivery application
Published in Chemical Engineering Communications, 2021
Fatmawati Adam, Mohd Aiman Hamdan, Siti Hana Abu Bakar, Mashitah Mohd Yusoff, Rajan Jose
Intermolecular hydrogen bond (Inter-H) refers to a H-bond occurs between separate molecules in a substance, whereas intramolecular hydrogen bond (Intra-H) refers to a H-bond within one single molecule (Knowles et al. 2007; Kondo 1997; Kroon et al. 1994). From the FTIR spectra, the influence of the network formation in the crosslinked carrageenan film can be determined by integrating the peak area at specific wavelength range (Hamdan et al. 2018; Mohd Amin 2016). Wavelength range from 3550 to 3200 cm−1 represents the intermolecular bonding of OH, whereas 3200–2700 cm−1 represents its intramolecular bonding (Lingegowda et al. 2012; Sigma-Aldrich 2018). The incorporation of up to 2 wt.% isovanillin increased the inter-H bonding by 80% from 57.74 cm−1 to 104.08 cm−1. Meanwhile, crosslinking of 3 wt.% isovanillin in carrageenan increased the intra-H bond by 53.48% from 27.85 cm−1 to 42.47 cm−1. The addition of 4 wt.% and 5 wt.% isovanillin corresponds to inter-H bonding of 39.77 and 53.67 cm−1, respectively.