The purpose of this work was to fabricate mechanically tough and flexible nanofiber web using polyurethane (PU) incorporating thin multi-walled carbon nanotubes (T-MWNTs) via solution blow spinning(SBS) method and investigate morphological, mechanical properties of PU/T-MWNTs nanowebs.
There are many ways to fabricate composite materials. Among others, polymer nanofibers have been widely used in a method of making a composite materials because of high specific surface area, surface adsorption, flexibility, and selective permeability. SBS is one of the technique for fabricating the sub-micron fibers by utilizing air, nitrogen or argon pressure. Unlike the electrospinning, almost all materials can be spun due to conductivity is not required in the base material. Further advantages of this process are a simple process, low initial cost, high efficiency and safety.
PU is one of the most versatile materials and used for various applications. It is selected as an interesting matrix polymer for several reasons, including the possibility of significantly improving resistance against mechanical deformation.
To improve the properties of the composite material, a method of adding a nano-filler in the polymer is used often. It is effective to improve composite properties into a small quantity of nano-filler because of the large surface area. In this study, we used the T-MWNTs as reinforcing agent.
First, we found the PU nanofiber condition with PU concentrations in case of using SBS. Second, we observed the properties at several solvent mixture ratio of DMF/THF, when THF ratio of solvent is higher, nanofibers diameter and tensile strength increased also. We successfully fabricated PU/T-MWNTs nanofiber webs at 10 wt% of PU concentration, 5:5 (w/w) ratio of DMF:THF and 0.5 to 5.0 wt% of T-MWNTs. Among them, PU/T-MWNTs nanofiber webs exhibited the most excellent mechanical properties with addition of 3.0 wt% of T-MWNTs. The prepared nanowebs showed the improved tensile strength (102 %), elongation (166 %), strain energy (167 %) and thermal property compared to pure PU nanowebs.
As these results, we successfully fabricated and characterized proerties of PU/T-MWNTs nanofiber webs using SBS method. Also, we should be expected that this material would be applied to apply to the tissue engineering scaffold, wound dressing or water treatment membrane etc.