%0 Journal Article
%T Demicellization of Polyethylene Oxide in Water Solution under Static Magnetic Field Exposure Studied by FTIR Spectroscopy
%A Emanuele Calabr辰
%A Salvatore Magaz迄
%J Advances in Physical Chemistry
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/485865
%X FTIR spectroscopy was used to investigate the alterations of the vibration bands in the mid-infrared region of Polyethylene oxide in aqueous solution at 25ˋmg/mL concentration under exposure up to 4ˋh to a static magnetic field at 200ˋmT. FTIR spectroscopic analysis of PEO solution in the range 3500每1000ˋcmˋ1 evidenced the stretching vibrations of ether band, C每H symmetric-antisymmetric and bending vibrations of methylene groups, and the C每O每C stretching band. A significant decrease in intensity of symmetric and asymmetric stretching CH2 vibration bands occurred after 2ˋh and 4ˋh of exposure, followed by a significant decrease in intensity of scissoring bending in plane CH2 vibration around 1465ˋcmˋ1. Finally, the C每O每C stretching band around 1080ˋcmˋ1 increased in intensity after 4ˋh of exposure. This result can be attributed to the increase of formation of the intermolecular hydrogen bonding that occurred in PEO aqueous solution after SMF exposure, due to the reorientation of PEO chain after exposure to SMF. In this scenario, the observed decrease in intensity of CH2 vibration bands can be understood as well considering that the reorientation of PEO chain under the applied SMF induces PEO demicellization. 1. Introduction Polymers are substances whose molecules have high molar masses, formed by repeated linking of small molecules called ※monomers§. Some natural polymers are proteins, starches, cellulose, and latex. Synthetic polymers are produced commercially on a large scale and have a wide range of properties and uses, such as plastics. Water-soluble polymers may be used in industrial and consumer products such as polymeric surfactant, pigment dispersants, or detergents, due to their properties of assembly in spherical micelles and vesicles that may be used as drug delivery vehicles. Indeed, several polymers can aggregate in micelles and can be considered good candidates for drug delivery purposes [1每4]. An important property of polymers is crystallization. The long chains of repeating monomers of a polymer form stacks of parallel chains called lamellae, that fold back on itself, as explained by [5, 6]. If crystallization is increased, the polymers tend to be stronger and more rigid, however this can lead to brittleness [7, 8]. Polymers structure have been accurately studied using neutron scattering techniques [9, 10]. In particular, the structure of polyethylene oxide (PEO) micelles is well described by the core-corona model [11每13]. PEO crystallinity was found by [14]. PEO is one of the simplest polymers, composed of chains of repeating 每CH2每
%U http://www.hindawi.com/journals/apc/2013/485865/