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通过调控接收板温度,实现了热塑性聚氨酯材料的熔体静电直写制备。通过模拟发现,当纺丝距离为5 mm时,接收板温度升高后,纺丝区间内温度呈线性提高,有利于减缓射流的冷却速度。通过实验探究了不同接收板温度对熔体静电直写制备热塑性聚氨酯材料纤维直径、形貌、沉积精度以及三维网格形貌的影响。实验表明,当接收板温度为80℃时,平均纤维直径与40℃时相比,降低了27.7%;当接收板温度100℃时,纤维沉积误差与60℃时相比,降低了46.8%;当接收板温度为80~100℃时,能够制备稳定的三维纤维结构;当接收板温度为120℃时,射流无法凝固为纤维。 相似文献
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将丝素蛋白(SF)和乳酸-羟基乙酸共聚物(PLGA)溶解在六氟异丙醇中配制成溶液,采用静电纺丝技术制备了SF/PLGA纳米纤维支架,使用扫描电子显微镜(SEM)对纤维支架进行表征,研究了聚合物溶液浓度、纺丝电压、接收距离以及体积流率对纳米纤维形态的影响,从而得到纺丝的最适宜工艺参数。考察了纤维支架表面对HUVECs细胞的相容性。结果表明:HUVECs可以在SF/PLGA纤维支架表面很好的黏附和增殖,支架具有良好的细胞相容性,在组织工程领域有良好的应用前景。 相似文献
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为研制出低成本高效过滤微滤膜,对熔体静电纺丝制备的聚丙烯(PP)纤维过滤膜进行了探究,通过改变电压、风速及温度等参数对单、双电极熔体静电纺丝进行试验,得出熔体静电纺丝双电极电纺膜性能优于单电极电纺膜的结论。采用熔体静电纺丝双电极装置制备出平均纤维直径2μm的过滤膜,验证了采用熔体静电纺丝制备高通量过滤膜的可行性,通过对比得出熔体电纺过滤膜的纯水通量是市售孔径0.45μm PP过滤膜的5倍之多,且对大于其纤维直径的微粒的截留率高达95%以上,力学性能好,可用作预过滤膜对污水进行预处理。 相似文献
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Melt electrospinning onto cylinders: effects of rotational velocity and collector diameter on morphology of tubular structures 下载免费PDF全文
Tomasz Jungst M Lourdes Muerza‐Cascante Toby D Brown Marco Standfest Dietmar W Hutmacher Jürgen Groll Paul D Dalton 《Polymer International》2015,64(9):1086-1095
Melt electrospinning writing is a direct‐writing additive manufacturing process that involves depositing a continuous, viscous and electrohydrodynamically stabilised molten jet onto a collector. Here, molten threads of medical‐grade polycaprolactone (PCL) are directed towards stationary/rotating cylindrical collectors (0–6600 rpm), including very slow revolutions well below the critical translation speed (approximately 600 mm min?1) of the molten jet. In this slow‐rotation region, the speed of the jet is faster than the movement of the collector and buckled/coiled fibres are produced due to compressive viscoelastic forces. The results are porous PCL tubes with wall morphologies often associated with viscoelastic liquids impinging onto a surface. The curvature of the collector affects how the fibre is deposited, with preferential fibre deposition along the axis of the cylinder. When the collector rotation speed is increased to greater than the speed of the jet, then straight fibres are produced. Such tubular structures have applications in tissue engineering. © 2015 Society of Chemical Industry 相似文献
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作为一种新型的微纳制造技术,熔体直写电纺被广泛用于组织工程支架的可控制备,有序的纤维沉积是该领域应用的前提条件。对于支架成型精度的探究,本文使用生物可降解材料聚己内酯(PCL),采用自行设计的熔体电纺三维可控成型设备进行实验,考察了纤维间距对二维并行纤维沉积形貌及成型精度的影响,以及纺丝电压和网格大小对三维网格结构形貌及精度影响。结果表明,随着并行纤维设定距离的增大,纤维的沉积误差减小,并最终趋于平稳。对于三维网格结构,随电压的增加,最大沉积层数量先增大后减小,当纺丝电压为6kV时达到最大沉积层数15层。成型精度误差先减小后增大,当纺丝电压为7kV时,精度最高误差小于5%。随设定网格边长的增大,沉积层数不断增大。成型精度逐渐提高,当网格边长大于等于1.5mm时,沉积误差趋于稳定,并维持在5%左右。 相似文献
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目前聚合物熔体电纺技术制备的纤维大多以杂乱无序的无纺布形式存在,限制了电纺技术在组织工程支架以及机器人等需要有序结构领域的应用。本文将熔体电纺技术与三维运动平台相结合,采用自主设计的熔体电纺可控成型实验装置,对聚己内酯(PCL)进行熔体直写静电纺丝,获得了有序纤维。研究了喷头移动速度、接收距离和纺丝电压对熔体直写电纺纤维沉积形貌的影响。结果表明,纤维直径随着喷头移速、接收距离和纺丝电压的增大而减小,其中接收距离的改变对直径的影响最为显著;接收距离的增大虽然有利于纤维的细化,但是距离过大会使纤维沉积的有序性变差;当射流下落速度与喷头移动速度相匹配时,射流才能实现有序沉积;增大接收距离和纺丝电压会引起射流鞭动,需要相应地增大喷头移动速度才能实现有序沉积。 相似文献
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Melt electrospinning writing (MEW), a computer-aided fiber deposition process based on an electrohydrodynamic working principle, enables the rational design and fabrication of fibrous scaffolds with micrometer thin fibers. So far, MEW has mainly been applied for poly(ε-caprolactone). Here we manufactured scaffolds of poly(2-ethyl-2-oxazoline), a hydrophilic polymer with high melting temperature, by MEW for the first time. We systematically varied and investigated the crucial instrument parameters: heating temperature (200–220 °C), feeding pressure (1.0–3.0 bar), accelerating voltage (3.0–7.0 kV) and collector distance (3.0–7.0 mm) in dependence of differently sized spinnerets (23 G, 25 G, 27 G, 30 G). As criteria for homogeneous deposition, we studied the resulting fiber diameters which could be adjusted from 8 μm to 138 μm and the corresponding variances. Furthermore this letter clarifies the need of a dynamic balance between involved mass flows in order to reduce pulsing failures of the jet and thereby structural defects of the deposited structures. 相似文献
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探讨了熔体直纺单板细旦涤纶POY 350 dtex/384 f生产工艺以及纺丝组件、冷却条件及集束上油、缓冷区、拉伸工艺等条件对产品质量的影响。结果表明,通过环吹风压的调整和优化工艺可以生产出优质产品。 相似文献
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静电纺丝是目前唯一能够直接、连续制备聚合物纳米纤维的方法,为了深入了解熔体静电纺丝纤维下落过程中的变化情况,探索用耗散粒子动力学介观模拟方法创建了静电纺丝模拟体系,模拟出聚合物黏度对不同阶段纤维下落速度的影响,发现纤维下落速度增加到一个最大值时,又逐渐变小;还模拟了聚合物不同链长时纺丝纤维的下落形貌,发现随着链长增加,纤维下落速度逐渐减慢;最后研究了弹簧系数对下落过程中聚合物均方末端距的影响,均方末端距增加到一个最大值时,又逐渐变小。从介观模拟的角度对熔体静电纺丝纤维下落过程进行了模拟探索,对这一物理现象中的科学问题得到了更深层次的理解。 相似文献
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探究了聚己二酸对苯二甲酸丁二醇酯(PBAT)熔体静电纺性能,并研究了熔体微分静电纺工艺参数与PBAT纤维性能之间的关系。结果表明,随着纺丝温度的升高,纤维直径减小,纤维直径分布呈先减小后增大的趋势;随着纺丝电压的升高,纤维直径减小且分布均匀,纤维膜力学性能逐渐提高;当纺丝距离为9 cm,纺丝温度为260 ℃,纺丝电压为45 kV时,制备的纤维细度及均匀度最佳,其直径为4.31 μm,直径分布标准差为0.76,纤维膜拉伸强度为9.9 MPa、断裂伸长率为111.2 %。 相似文献
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对熔体直纺细旦FDY 44 dtex/48 f的生产工艺进行了介绍。探讨纺丝组件、冷却条件及集束上油、缓冷区、拉伸工艺等条件对产品质量的影响。结果表明,通过侧吹风室的改造和优化工艺可以生产出优质产品。 相似文献
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Melt electrospinning technique has shown great advantages in numerous areas where polymer dissolving, solvent accumulation, or toxicity is a concern in solution electrospinning. However, conventional capillary spinnerets in electrospinning are less productive. In this article, two needleless umbellate nozzles were used based on melt differential method, and the smallest interjet distance of 1.1 mm was observed. Experimental results indicated that the main factors affecting the interjet distance were the electric field strength and melts viscosity. The produced fiber diameter was related to interjet distance directly. Finite element modeling (FEM) showed that umbellate structure determines the intensity of maximum electric field around the rim of nozzles and the resultant interjet distance. This new method enabled the mass production of ultra‐fine fibers using needleless melt electrospinning method when relatively low voltage (less than 65 kV) was loaded on the receive plate. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40515. 相似文献