Study On The Preparation And Properties Of Zein/Poly (ε-caprolactone) Composite Ultrafine Fibrous Membranes Via Electrospinning

In this thesis, zein/Poly (ε-caprolactone) composite ultrafine fibrous membranes wereprepared via electrospinning，and zein-Poly (ε-caprolactone) core-shell composite ultrafinefibrous membranes were prepared via co-axial electrospinning. The morphology and structure ofthe composite ultrafine fibrous membranes were investigated. The results showed that thediameter of the fibers firstly decreased then increased, and the crystallinity of the fibrousmembranes became better with increasing of PCL content in the fibrous membranes. But the twokinds of content was at phase separation condition,and never reacted with each other. themechanical properties of zein/PCL composite ultrafine fibrous membranes get better and betteras the content of PCL increased. Through vitro cell culture experiment, the biologicalproperties of the five kinds of ultrafine fibrous scaffolds was investigated. The results showedthat the L929mouse fibroblasts proliferated well on both of the two fibrous membranes.when the two content ratio was30/70in blend fiber membrane,and inner and outer layerflow rate were0.01ml/min and0.008ml/m in coaxial composite fiber, the amount andrelative ratio of the two kinds of fiber membrane was at the same.Through horizontalcoMParison, the average fiber diameter was of less slightly soft and tough in blend electrospunzein/PCL composite, fibrous membrane, and the tensile stress of coaxial electrostatic spinningzein-PCL core-shell structure composite scaffolds was greater, and has better cell coMPatibility.In order to orientate the zein/PCL composite superfine fiber membrane scaffold to bonetissue engineering applications, hydroxyapatite nanoparticles which has osteogenic activity wasadded to the two kinds of fiber preparation above, then the composite fiber membrane of threecomponents blend wasprepared.In nHA/zein/PCL composite superfine fiber film, As the hydroxyapatite content increased,the fiber diameter reduced gradually, the fiber surface becomes uneven, which was moreconducive to cell adhesion, and as a result of particle reinforced effect, mechanical properties ofnHA/zein/PCL composite superfine fiber film Improved firstly and then then droped. When the content of nHA was30%, the composite fiber membrane has the highest content of nHA withgood mechanical properties, culturing MG63human osteosarcoma cell shows that, both adhesionand appreciation effect improved after adding nHA to the composite fiber.In nHA/zein-PCL core-shell composite ultrafine fibrous membranes, nHA particles wereuniformly doped in zein, as nHA content in shell substance increased,the diameter of the fibersincreased first and then decreased, fiber surface roughness increased, the crystallizationperformance of PCL becomes worse, when nHA crystallization becomes better. CoMPared to thenHA/zein-PCL-0coaxial composite superfine fiber, nHA/zein-PCL-30composite superfine fiberhas best mechanical properties. The initial Young’s modulus was286MPa when fracture stress26.7MPa,,fracture strain83%. Though cultured MG63cell on it showed that, addingnanometer hydroxyapatite can significantly improve nHA/zein-PCL core-shell structure ofcomposite fiber cell adhesion and value-added performance, ALP activity also increased. Cellsgrowth was in good condition.For the zein/PCL composite fiber and zein-PCL coaxial core-shell structure of compositefiber, both of which has the same quality and the same quality ratio(30/70), when the blendingcontent of nHA was30%, the fiber morphology, mechanical properties and biocoMPatibility wascoMParatively studyed, the filament of nHA/zein/PCL composite fiber was more, promiscuity,its diameter error was large, and the coaxial core-shell structure of nHA/zein-PCL fiber surfacewas neat, smooth. The nHA/zein/PCL composite fiber membrane tensile stress was of30.1MPa, tensile strain was only48%, the young’s modulus was270MPa, relatively hard and brittle,and tensile failure strain of nHA/zein-PCL core-shell structure composite fiber was83%, butthe fracture stress was lower, relatively soft and tough. In this case, core-shell structure nHA/zein-PCL composite fiber scaffolds prepared via coaxial electrospinning for cell culture resultswas better.