Compatibility And Electrospinning Properties Of PVPh/PEO Blends

This work is mainly about the compatibility and the performance of electrospinningof PVPh/PEO polymer blends. It contains three aspects：First，the solubility parameterwas used to predict the compatibility which was characterized by the glass transitiontemperature (Tg) of the blends from the differential scanning calorimetry (DSC) and thestructure information from Fourier transform infrared spectroscopy (FT-IR); Second,polymer blends solution was prepared through solution blending and the rheologicalproperties of the solution were studied. In addition, the films of the blends were cast in aPVDF mold and the mechanical properties and thermal stability of the films weremeasured. Last, polymer blends nano-fibers were prepared by electrospinningtechnique,and the collection setup and processing parameters were varied to change thearrangement and morphology of the nano-fibers.The results of this study showed that the PEO was compatible with PVPh, and asingle Tgwas observed in the blends with different contents of PEO. The compatibility ofblends was improved by the strong interaction of hydrogen bonding between PEO andPVPh, as shown in the FI-IR spectra. The molecular chains entangled increased whenPEO added, the flow resistance of the blends solution increased too. The rheologicalproperties showed that the polymer blends solution belonged to non-Newtonian fluid.The interaction between the ether group on PEO chains and the hydroxyl group onPVPh chains improved the thermal stability of the blend. The transmission rate of theblend films could reach70%in the range of visible light. Meanwhile, the flexible PEOcomponent improved the flexility and impact performance of the PVPh thin films..The results of electrospinning indicated that PEO increased the entanglement ofPVPh molecular chains which would improve the spinnability of the blend solutions. Inthe process of electrospinning, the roller was adopted to collect the well-alignednanofibers and the greater the roller speed was, the smaller the fibre diameter was and themore uniform the fibre diameter distribution. For a given electro-spinning solution, therewere suitable technique parameter ranges. The diameter of the fibers increased with the increasing of the solution’s viscosity, but decreased with the increasing of voltage.Meanwhile, the high voltage could reduce the yield of the fiber. The acceptance distanceinfluenced electric field intensity, thus affecting the diameter of fiber, and therefore asuitable contact distance would be benefit to obtaining fiber possessed uniform diameterdistribution.