Preparation Of Highly Aligned Polycaprolactone Nanofiber Yarns And Its Properties

With the progress of medical technology and textile engineering.Textile materials are widely used in the medical industry.Now the study of medical textile materials are no longer confined to the current status,but gradually combined with the high technology to get the medical textiles with high added value.Compared with traditional textile processing technology,Nano-technology can be used to process fiber of diameter as low as a few nanometers,endowing the material with many new functions,such as: volume effect,surface effect.As biomedical materials,nano fibers,having a small diameter,which can effectively simulate the morphology of fibers in the human extracellular matrix,have broad application prospects in the biomedical field.So far,electrospinning is one of the most directly and effective methods to prepare nanofibers.However,most of the nanofibers are collected in the form of non-woven fabrics,due to their chaotic structure,low mechanical properties and lack of stitching,which can not be applied to the traditional textile field.The oriented electrospun nanofiber yarn,which gradually concerned with its characteristic of one-dimensional linear continuous fiber assembly,can be used for textile processing technology,such as:traditional weaving,weaving,knitting etc,to get three-dimensional nano fiber assembly whose size,shape,size and mechanical properties are highly controllable,meeting the various need of different applications.In this paper,the PCL oriented nanofiber yarn were successfully prepared by using modified electrospinning technique and the researching of different spinning parameters.Then the obtained continuous PCL nanofiber yarns were employed to plain fabric by traditional textile techniques,preparing for the application in the tissue engineering.First of all,from the point of biological medicine,considering the mechanical properties and the apparent morphology,the optimal process parameters were selected as below: spinning concentration of 0.10 g /ml,spinning voltage of 9 k V,solution flow of 1 ml/h,spinning distance of 20 cm,distance between neutral metal disc（NMD）and neutral hollow metal rod（NHMR）of 7 cm,rotation speed of NMD of 250 r/min.Using the optimal process parameters,the high orientation of nano fiber yarn with a diameter about 600 nm,whose fiber morphology and fiber morphology is similar with human tissue cells,which can be widely applied in human nerve,blood vessels etc.,has a good application prospect in biomedical field.Secondly,in order to study the effect of degradation on PCL nanofiber yarn,PCL nanofiber yarn were got degradation in vitro,using PBS phosphate buffer solution and 0.1 mg/L lipase.The results showed that the surface of PCL nanofiber yarn was broken,and the yarn shape was completely destroyed when the degradation time was prolonged,and as the degradation time increased,the yarn weight loss rate increased,the strength and elongation decreased,and the initial modulus increased at first and then decreased.Thirdly,the antibacterial property of PCL nanofiber yarn was made by adding antibacterial agent of C₁₂H₇C₁₃O₂ to the spinning solution.The results showed that there was no significant effect on the average diameter and tensile properties of the nanofiber yarns and nanofibers with different antimicrobial agents content;and PCL nanofiber yarn has a good antibacterial effect after adding a small amount of C₁₂H₇C₁₃O₂,when the content of antibacterial agent to solute was 1%,,the antibacterial rate of bacterium coli and staphylococcus aureus has both reached more than 90%.Finally,in order to explore the potential of woven into different tissue according to the different needs,PCL nanofiber yarns were woven into plain fabric combining with traditional textile technology.The results showed that,the mechanical property of plain fabric nanofiber orientation were significantly greater than the nanofiber membrane,which meet the basic mechanical requirements of tissue engineering.And compared with the nanofiber membrane,fabric structure has larger pore size,higher porosity,which is more benefit to cell attachment,proliferation,then penetratly growth into the interior.The weft of orientation nanofiber yarn increased cell attachment point and overcome the the disadvantages of nanofiber membrane not easy to operate and control,has a broad prospect in tissue engineering and biomedical fields.