经编人造血管编织设备的研究现状

对人造血管的研究涉及4个方面的问题,即人造血管的材料、结构设计、基础结构件的制造和后处理方法,其中,基础结构件的制造及相应编织设备的开发是生产人造血管的关键。文章对目前使用的几种人造血管基础结构件制备方法及相应设备进行了分析、比较,根据临床应用中的效果,经编人造血管在实际临床中应用得较为广泛。对国内两家生产经编人造血管厂家的产品进行了介绍,分析了各自的结构特点,并展示了编织的人造血管实物。     

辛普勒克斯经编织物的编织工艺探讨

介绍了新型辛普勒克斯经编机的特点，对其工艺作了探讨。     

经编菱形网格织物的性能研究

介绍几种经编菱形网格织物的组织结构和性能特点,测试这几种织物的面密度、厚度,以及单向拉伸断裂强力和顶破强力等力学性能,并进行数据分析。结果表明:不同经编组织结构对织物的物理和力学性能影响很大,面密度随牵拉密度的增加而增大,横向断裂强力和纵向断裂伸长率随牵拉密度的增加而增大,顶破强力与网格边长大小成反比关系。     

经编长效蚊帐织物的顶破性能研究

为研究经编长效蚊帐在使用过程中的顶破性能,采用不同组织与材料编织经编网眼织物,对这些织物进行顶破性能测试分析。对比各试样顶破强力与顶破伸长的差异,观察织物破裂时结构的瞬间变化情况,以及研究在试验中织物受力与形变的关系,并建立了一套经编织物顶破性能的观察系统。结果表明:涤纶和聚乙烯经编网眼织物的力学性能有明显不同;相同材料的网眼织物,纱线线密度越大、织物克质量越大,抗顶破性能越好;六角网眼结构比四角网眼结构抗顶破性能好,但四角网眼结构能在织物破裂后更好地阻碍织物的脱散。     

经编结构血管外支架的编织及其性能研究

为了得到一种脱散性较小、弹性较好的新型结构血管外支架,在小口径高速圆筒经编机上织制了经编结构血管外支架,并对支架的轴向拉伸性能及径向压缩性能进行了测试,同时分析了支架口径的变化对其性能的影响。     

纺织基人造血管管壁水渗透性和孔径分布研究

探讨纺织基人造血管管壁水力学性能表征指标的关系.采用依据国际测试标准设计制造的纺织基人造血管水渗透性测试装置,测试了各种结构的织物和各种类型的人造血管的水渗透性、孔隙率、平均孔径和孔径大小的分布,并对样品的水渗透性、孔隙率和平均孔径的关系进行了比较分析研究.试验研究表明:虽然人造血管织物的孔隙率在很大程度上影响其水渗透性,但是当织物结构不同时,即使孔隙率相近,水渗透性呈现很大的分散性.而对于一般结构人造血管织物来说,其平均孔径与水渗透性有良好的线性相关关系.     

经编网格织物的性能研究

经编网格织物在产业用领域的应用空间越来越大,随着产业用网需求的增加,经编网格织物的物理性能和机械性能受到越来越多的关注。本文介绍了10种常用经编网格织物的组织结构和性能特点,其中组织结构包括两梳和三梳组织,满穿和空穿组织,以及普通组织、缺垫组织和衬纬组织。分别对这10种织物进行克质量和厚度等物理性能的测量以及单向拉伸断裂、双向拉伸断裂和顶破性能等机械性能的测试,并做数据分析,得出不同组织结构形成的经编网格织物的性能特点。     

三维管状编织复合材料的弯曲性能研究

以1 200 tex的E型玻璃纤维为原料,采用3DB-J100-8型模块化组合三维编织平台制备三维四向、三维五向管状编织物;以E51环氧树脂、H023聚醚胺组成树脂基体,与上述编织物复合制成三维管状编织复合材料;利用Instron 3385H型万能材料试验机测试并观察材料的弯曲性能,研究编织结构、编织角等结构参数对三维管状编织复合材料弯曲性能的影响规律。结果表明:三维管状编织复合材料破坏特性均表现为明显的脆性破坏;三维五向管状编织复合材料的抗弯性能明显好于三维四向管状编织复合材料;三维管状编织复合材料的弯曲性能均随编织角的增大而增加。     

纱线类型对腔内隔绝术用人造血管疲劳性能的影响

针对临床上腔内隔绝术用人造血管(SG)出现的疲劳破损导致其在体内的寿命难以达到预期要求的问题,利用一种新型体外测试装置预测腔内隔绝术用人造血管的疲劳性能。采用加速疲劳实验,脉动压力为64kPa,脉动频率为10Hz,除了循环脉动流之外,此装置还提供SG移植环境——模拟血液环境。重点研究了纱线类型对腔内隔绝术用人造血管疲劳性能的影响,结果表明经纱为单丝的SG比经纱为复丝的SG更易疲劳。     

紧密纺纯棉经编产品的编织工艺探讨

介绍了紧密纺的纺纱机理和紧密纺棉纱的特点,通过对经绒平组织的试织,探讨了在机号为28针/25.4mm的HKS2型经编机上开发经斜平和变化网眼组织紧密纺纯棉产品的编织工艺.紧密纺棉纱强力虽然较高,但捻度较大,易纠缠断纱,因此在整经时最好采用分层分纱的方法;编织过程中,在保证正常编织的条件下,送经张力和牵拉张力应尽可能减小;机速不宜太高,文中选择的机速为1 200r/min;要严格控制车间的温湿度,温度在(24±2)℃、湿度在(70±5)%左右时为宜.     

仿棉涤纶长丝经编织物的沸水收缩率及其影响因素

本文对涤纶长丝仿棉经编织物的织缩率和沸水收缩率进行了实验研究与分析,通过图表分析与不等水平正交实验分析的方法,探讨了涤纶长丝仿棉织物缩率的相关规律及影响织物织造沸水缩率总缩率的主要因素。实验结果证明：不同的织物组织设计对于涤纶长丝仿棉经编织物的收缩率有一定规律性的影响,机上纵密是影响织物收缩率的最主要因素。     

热粘结复合纤维人造血管支架的制备及其性能

为制备力学性能优异、无细胞毒性和耐穿刺性的小口径人造血管,采用静电纺丝技术结合浸泡脱管法制备了聚己内酯/聚氨酯(PCL/PU)小口径人造血管支架.借助扫描电子显微镜和万能力学拉伸机等对人造血管的形貌结构和力学性能进行测试,同时研究了人造血管支架的孔隙率、细胞毒性和耐穿刺性.结果表明:通过改变接收转辊尺寸,溶去内层聚乙烯...     

玻璃纤维多轴向经编复合材料的制备及拉伸性能研究

以环氧树脂为基体,分别以玻璃纤维多轴向经编针织物和玻璃纤维机织物作为增强材料,通过手糊法制备复合材料,并通过试验对比研究两种复合材料的拉伸性能。结果表明,经编复合材料沿各个轴向的拉伸强度比复合前多轴向经编针织物及机织复合材料的强度均有明显提高,增幅均在50%以上,说明多轴向经编复合材料具有更优异的力学性能。这为进一步扩大玻璃纤维多轴向经编复合材料的应用领域提供了有力证据。     

An analysis of the bending rigidity of warp-knitted fabrics: a comparison of experimental results to a mechanical model

This study focuses on the bending rigidity of warp-knitted fabrics as a function of knit structure (underlaps length), density (wale and course spacing) and yarn bending properties. Seven standard warp-knitted fabrics are produced with three different densities (Tricot, Locknit, three and four needles Satin, Reveres Locknit, three and four needles Sharkskin). The bending rigidity of the fabrics is measured using a Kawabata evaluation system and an automatic cyclic bending tester. Results show that the bending rigidity increases for the fabrics with a higher density and underlaps length of the front and back guide bars. In addition, a new mechanical model for the bending behaviour of warp-knitted fabrics using an energy method is presented. In this model, the knitted loop structure is assumed to consist of a series of straight and skew yarns simulating legs and underlaps while considering a rigid region lying in the direction of bending. Experimental results show that there is a reasonable agreement between the calculated and measured values for both wale and course directions.     

Warp and weft directional tensile properties of multistitched biaxial woven E-glass/polyester composites

The objective of this research work was to understand the warp and weft directional tensile properties of the two-dimensional multistitched multilayer E-glass/polyester woven composites. The warp and weft directional specific tensile strength and modulus of unstitched structure were higher than those of multistitched structures as stitching caused minor warp and weft yarn filament breakages. Contrarily, the specific tensile strains of unstitched structure were slightly lower than those of all multistitched structures. The stitching yarn type, the number of stitching directions, and the stitching density generally influenced the warp and weft directional tensile properties of multistitched E-glass/polyester woven composites. The failure of warp and weft directional multistitched woven E-glass/polyester composite structures was matrix breakages, and partial and complete yarn breakages in their surfaces. They had a local delamination in their cross-sections and the delamination did not propagate to the large areas due to multidirectional stitching. Also, the failure was confined at a narrow area and resulted in the catastrophic fiber breakages. The warp and weft directional specific damaged areas of multistitched structures, in particular four-directional stitching, were significantly lower than those of the unstitched structures. This indicated that the multistitching made the structures better damage-tolerance materials.     

双轴向经编涂覆织物剥离性能研究

研究了织物组织结构和成型工艺对双轴向经编双面涂覆织物剥离性能的影响。结果表明,双轴向经编涂覆织物由于经纬纱取向及捆绑纱的排列不同,使涂覆织物各个面各个方向的层间黏合强度相差较大;通过流延覆膜工艺生产的双轴向经编涂覆织物在高频热合加工后层间黏合强度有较大幅度的增加。     

Comparison of fabric properties knitted by pin spacer compact and conventional compact yarns

This study examined the influence of pin spacer apparatus attachment on compact yarn quality parameters and physical properties of knitted fabrics manufactured using those 100% cotton compact yarns. Two groups of compact yarns were spun on regular compact yarn spinning frame with and without addition of pin spacer apparatus which is placed at the end of the drawing unit of regular compact yarn spinning frame. Totally eight yarns were spun at four different yarn number levels (Ne 24/1, Ne 30/1, Ne 36/1 and Ne 40/1) and two different spinning conditions (with and without pin spacer apparatus). Spun yarn types were then knitted on the industrial sized plain knitting machine. Knitted fabrics were used in the greige and dyed form to evaluate their bursting strength (kPa), dimensional change, abrasion related mass loss (%), pilling resistance, air permeability (mm/s) and colour difference. Test results were then statistically evaluated and influence of pin spacer attachment on yarn quality parameters and fabric properties was determined. In the frame of this experimental work, attachment of pin spacer apparatus improved compact yarn characteristics especially at yarn evenness, imperfection and hairiness values. In case of knitted fabric properties, it was found that pin spacer apparatus attached compact yarn utilization significantly improved air permeability properties of knitted fabrics.     

涤纶基材碱减量处理对建筑膜材力学性能的影响

建筑膜材是发展相当迅速的一类复合材料。为提高膜材的剥离强度,采用碱减量的方法对涤纶基材进行处理,研究了碱减量处理工艺对其膜材机械性能的影响。实验发现,通过对涤纶基材进行碱减量处理,可有效地提高其建筑膜材的剥离强度,但对拉伸断裂强度有一定的影响。     

机织针织复合织物与多层双轴向纬编织物拉伸性能对比

选用玻璃纤维作经纱、纬纱和高强涤纶作针织纱分别编织机织针织复合(CWK)织物和多层双轴向纬编(MBWK)织物,测试两种织物的横向、纵向的拉伸性能,分析比较拉伸负荷和位移特征曲线。研究表明：在拉伸过程中,CWK织物MBWK织物均先由其中的经纱或纬纱,在较低的伸长下,承担较高的负荷,直至经纱或纬纱断裂,然后由针织结构,在较高的伸长下,承担较低的负荷,直至针织结构破坏;经纱和纬纱以交织形式衬入针织结构中,使得CWK织物的轴向的拉伸强度稍低于MBWK织物,但起到一定的“预牵伸”作用,可使针织纱对经纱和纬纱捆绑效果更好。