Light Scattering Study of the Effect of n-Butanol on the Micellar Properties of Undecylammonium Chloride in Aqueous Electrolyte Solutions

Effects of the cosurfactant 1‐butanol and feed composition on nanoparticle properties produced by microemulsion copolymerization of styrene and methyl methacrylate

“…These standards were analyzed directly on the ATR crystal and four spectra were collected per standard. Calibration curves were constructed by plotting the absorbance ratio of two peaks, which could be assigned unambiguously to either the styrene monomer ($ 699 cm 21 for the out of plane bending of the phenyl ring) and for the methacrylate monomer (saturated alkyl ester carbonyl stretch at $ 1729 cm 21 ), versus the mole fraction ratio (f St ) of the two homopolymers employed in each set.…”

“…The multi-angle laser light scattering (MALLS) detector consisted of a 5 mW He-Ne laser that illuminated samples at a wave-length of 632.8 nm. The MALLS detector was carefully calibrated with filtered HPLC grade toluene (BDH, Merck) and then normalized with an isotropic scattering poly (styrene) (PS) standard (M w 30,000 g mol 21 , polydispersity < 1.05, Pressure Chemical Company, Pittsburgh, PA, USA). The MALLS was connected to a refractive index (RI) detector (Agilent 1 1100 series) to determine concentration of the eluting species.…”

“…[36][37][38][39] The (ATR) procedures were performed in the mid-IR region and spectra were recorded in the region 4000-650 cm 21 . A Bruker Equinox TM 55 (Bruker, Ettlingen, Germany) IR spectrometer was employed for all data collections.…”

“…The spectrometer utilized a He-Ne laser operated at 632.8 nm and was equipped with a micro ATR sampling accessory containing a ZnSe crystal. Spectra were recorded by coaddition of 32 scans with a spectral resolution of 4 cm 21 . Bruker Opus TM 5.1 software was employed to collect and process the ATR spectra.…”

“…6,[17][18][19]20,21 However, the inclusion of these short chain alcohols as cosurfactants into microemulsion copolymerization systems can result in seemingly inexplicable changes in molecular weight as a consequence of the variation of the cosurfactant concentration. Although not clearly understood, some explanations for these observations included the macroradical chain transfer to the cosurfactant and film formation around the surface of the micelle that shield polymer radicals.…”