Summary: This work considers the homogeneous aqueous phase polymerization of n-vinyl formamide(NVF). Thus, the effect of temperature, initiator and monomer concentration in the kinetics and molar mass distribution (MMD) of the polyNVF produced was experimentally assessed. SEC-MALS analysis was misleading because anomalous elution was found due to interaction of the polyNVF chains with the column. This was solved by analyzing the polyNVF by asymmetric-flow field flow fractionation chromatography coupled with multi-angle light scattering and differential refractive index, AF4/MALS/RI. The second part of this work considered the synthesis of nanoparticles based on polyNVF. Two routes were explored. In the first one the inverse microemulsion photopolymerization of NVF was attempted and polyNVF dispersions in isopar M with solids content of 18 wt% and particle sizes in the range 50-70 nm with average molar masses of several millions were obtained. In the second route PolyNVF produced in homogeneous aqueous phase was hydrolyzed to yield polyvinyl amine, PVAm. The resulting water soluble polymers were used to produce polymethyl methacrylate, PMMA, nanoparticles by surfactant free emulsion polymerization initiated by tert-butyl hydroperoxide TBHP. Stable pH responsive PMMA cationic nanoparticles with amino functionalities in the surface were easily produced.
The molar mass and the radius of gyration of three poly N-vinyl formamide (polyNVF) synthesized in aqueous solution polymerization were characterized using two different fractionation techniques: size exclusion chromatography (SEC) and asymmetric-flow field-flow fractionation (AF4) coupled with a multiangle light scattering (MALS) and a refractive index (RI) detector. For the sake of comparison, the polymers were also characterized by MALS using the Zimm plot approach (no fractionation). The dn dc 21 of the poly (N-vinyl formamide) was measured (0.1564 mL g 21 ) and it was found to be insensitive to the molar mass (in the range 150-450 kDa) and also to the eluents used (DDI water or mixed eluent DDI water/acetonitrile (80 : 20) at pH 5 5.5). Interestingly, the concentrations of the samples injected in the SEC and AF4 should be different because concentrations in the range of 20-40 mg mL 21 used for the AF4 caused overloading and anomalous elution in the SEC and hence misleading molar masses. At adequate concentrations in each fractionation equipment, the molar masses were in reasonable good agreement although AF4/MALS provided larger values than the other two techniques likely because samples were not filtered before injection. V C 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42434.
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