Study Of The Modification Of The Electrospun Nanofibrous Membrane Of Hyperbranched Polyurethane

Hyperbranched polyurethane, with desirable solubility, low viscosity, abundant end-groups, has been used as adhesives, coatings, elastomers, foam material, biomedical materials, etc. However, the rigid groups in hyperbranched polyurethane lead to the poor flexibility of its materials. Polycaprolactonediol (PCL) with flexibile segments is one of desirable candidates for modifying hyperbranced polyurethane materials to improve their flexibility.The electrospun nanofibers with controllable porous structure and high specific surface area are applied as various functional materials. Combined with the end group-rich hyperbranced polyurethane, it is possible for nanofibrous materials to achieve a desirable functionalization.Calixarene, as the third generation supramolecular host compound, exhibited some advantages like easy modification of its upper and lower edges, hydrophobic cavity capable of capturing ions or neutral molecules, etc. Therefore, Calixarene has a wide range of applications in the chemical or biological fields. Currently, the most applications of calixarene as sensor were confined onto the silicon surface. The introduction of calixarene into polymer-based materials will benefit its functionalization on material level.Two parts of research work were included in this thesis.First, PCL was incorporated into hyperbranched polyurethanes to improve their flexibility. The PCL-modified hyperbranched polyurethanes were electrospun into nanofibrous membrane, and the effects of PCL on the mechanical properties of materials were investigated.Second, calixarene was coupled to the chain end of hyperbranched polyurethanes via click chemistry. The modified polymers were electrospun into nanofibrous membrane. The selective recognization of pestcides by this material was achieved.