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In this work, a variety of hyperbranched polymers (HBPs), such as hyperbranched polycarbonates, polyesters, polyurethanes and polyacetals, was successfully synthesized from castor oil and soybean oil based monomers via a A2 + B3 polycondensation. First, B3 monomer triols (TriOL), trialdehydes (TriAD), and tricarboxylic acids (TriAC) were obtained by ozonolysis of castor oil and soybean oil with following reductive or oxidative treatment. Their structures were characterized by 1H NMR and ATR-FTIR spectroscopy as well as electrospray ionization-Time of Flight-mass spectrometry. These trifunctional B3 monomers were applied in the preparation of HBPs. The resulting HBPs had number averaged molar mass (Mn) up to 9400 g/mol and weight averaged molar mass (Mw) up to 40,000 g/mol. Through adjusting the initial molar ratio of A2 to B3 monomers, hydroxyl terminated (from TriOL monomers) or carboxylic acid (from TriAC monomers) terminated HBPs could be obtained. All the HBPs were characterized by 1H NMR, size exclusion chromatography, and DSC. These HBPs are potential candidates for the synthesis of cross-linked polymeric materials or in biomedical applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 2104–2114

In the present work, a new and facile strategy for the synthesis of light-responsive polyurethanes (LrPUs) based on serinol with o-nitrobenzyl pendent groups is developed. Stable monodisperse nanoparticles from these LrPUs can be formulated reproducibly in a simple manner, which is shown by dynamic light scattering (DLS) measurements. Upon irradiation with UV light, both polymers and nanoparticles undergo rapid degradation, which is investigated by DLS, scanning electron microscopy, size exclusion chromatography, and UV-vis spectroscopy. The nanoparticles are also employed for the encapsulation of the model drug Nile Red, and by exposure to UV light, a burst release of the payload is detected via fluorescence spectroscopy. This strategy can be easily applied to the straightforward synthesis of various new serinol-based monomers with different stimuli-responsive properties and therefore expand the family of biodegradable polymers.