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1.
目前,柔性链聚合物所制成的高强度高模量纤维的典型代表为超高相对分子质量聚乙烯(UHMW—PE)纤维、超高相对分子质量聚乙烯醇(UHMW—PVA)纤维。目前,制得PVA纤维的最高模量为115GPa,但迄今为止商用PVA纤维的最高强度仅为2.5GPa左右。PVA可以形成分子内和分子间氢键,使其熔点高达245℃,高于PE纤维。PVA要达到100GPa的高模量,仅需20倍的超拉伸,而PE纤维则需要200-300倍的超拉伸。作为理想的石棉、玻璃纤维取代品以及在国防军工中的防弹材料的应用,高强高模的PVA纤维的技术发展很快,其经济效益与社会效益正在被不断的发掘之中。目前,国内外开发高强高模PVA纤维主要从以下三方面进行:制备UHMW—PVA;制备高立构规整度的PVA;利用新型纺丝工艺技术制备高性能的PVA纤维。  相似文献   

2.
以常规聚合度聚合的乙烯醇(PVA,聚合度1 700~2 600)为原料,以二甲基亚砜(DMSO)为溶剂,乙醇为凝固剂,甲醇为萃取剂,采用干湿法纺丝制备高强度的PVA纤维,最高强度可以达到19.4 cN/dtex。使用扫描电子显微镜对PVA纤维样品进行观测,纤维样品的形貌结构十分均匀,这对提高PVA纤维的断裂强度十分有利...  相似文献   

3.
以壳聚糖(CS)为基材,使用静电纺丝的方法制备了搭载壳寡糖(CHOS)的CS/聚乙烯醇(PVA)/CHOS纳米纤维膜,并对纳米纤维膜的微观形貌、结构、抑菌性、亲水性以及溶解性能进行了研究。研究发现:CS/PVA/CHOS纳米纤维膜具备均匀密致的微观形貌;FT-IR测试表明,CHOS以物理混合的形式分散在CS/PVA/CHOS纳米纤维膜中;XRD测试表明,CHOS的加入改变了纳米纤维膜的结晶性,促进了各组分之间的相容性;水接触角测试表明纳米纤维膜具备良好的亲水性,在m(CS):m(PVA):m(CHOS)=20:80:10时,CS/PVA/CHOS纳米纤维膜的接触角相比于m(CS):m(PVA)=20:80的CS/PVA纳米纤维膜由59.8°下降到37.5°;抑菌性能和溶解性能测试表明,m(CS):m(PVA):m(CHOS)=20:80:10时的CS/PVA/CHOS纳米纤维膜相比于未搭载CHOS的CS/PVA纳米纤维膜,抑菌性提升了38.9%,溶解率提升了38.6%。  相似文献   

4.
通过简单的溶剂热法将球形BiOBr固定在电纺聚乙烯醇(PVA)/SiO2有机-无机杂化纳米纤维上,制备了柔性PVA/SiO2@BiOBr纳米纤维。电纺PVA/SiO2纳米纤维由Si—O—C—O—Si键桥链接而成,具有良好的机械强度、耐溶剂性和耐热性,且其表面含有未交联羟基,可为BiOBr晶体的生长提供成核位点,无需额外...  相似文献   

5.
功能户外防护材料中热能管理是一个重要的方面。对于功能织物开发而言,大都采用涂层后整理技术,但是其功能性和透气性的平衡是关键。本文以静电纺丝技术制备了聚乙二醇/氧化锑锡(PVA/ATO)纳米复合纤维膜,采用扫描电镜(SEM)、傅里叶红外光谱(FTIR)、X射线衍射(XRD)、热重(TG)对纳米复合纤维进行了表征,并对PVA/ATO/黏胶热轧复合材料的保温性能及透气性进行了测试。结果表明:PVA中ATO具有良好的分散性,部分ATO纳米颗粒镶嵌在纤维表面。PVA/ATO/黏胶热轧复合材料的保温率相对于基材黏胶热轧布提高了28.9%,达到37.1%,相应传热系数为12.62W/m2·℃,克罗值0.32。ATO纳米颗粒的加入可以直接改善PVA纳米纤维膜的堆积结构,使得PVA/ATO/黏胶热轧复合材料的透气性相对于PVA/黏胶热轧复合材料有明显提高,但趋势随纳米纤维层厚度的增加而降低。PVA/ATO纳米复合膜可以复合到多种基材上,从而为基于纳米纤维功能材料开发保温透气功能提供了思路。  相似文献   

6.
聚乙烯醇/水滑石共混纤维的制备及其性能研究   总被引:1,自引:0,他引:1  
采用凝胶纺丝法制备聚乙烯醇/水滑石(PVA/HT)共混纤维。通过扫描电镜(SEM)观察水滑石在PVA/HT共混纤维中的分散状况和共混纤维的表面形态。从傅里叶变换红外光谱(FT-IR)可以看出HT和PVA之间存在明显的氢键作用;热重分析(TG)测试表明水滑石的加入可以有效提高PVA的热性能;加入适量的HT可以提高PVA纤维的断裂强度;随着HT含量的增加,PVA/HT共混纤维的最大拉伸倍数下降且表面易产生缺陷。  相似文献   

7.
回顾了聚乙烯醇(PVA)纤维的发展,简述了PVA纤维及其衍生物的主要性能及生产应用。阐述目前亟待解决的PVA纤维产业化的难题,分析了PVA纤维市场潜力和应用方向,并对PVA纤维的发展做了展望。  相似文献   

8.
负载活性药物的水凝胶敷料能够通过药物的控制释放,防止细菌感染、消除炎症,从而有效促进伤口愈合,其性能与水凝胶的组成、制备方法以及药物负载过程有关。将3-氨基苯硼酸接枝的海藻酸钠(Alg-PBA)与聚乙烯醇(PVA)交联制备了水凝胶,研究了水凝胶的形成机理,考察了各组分质量比及PVA分子量对水凝胶形貌结构和流变行为的影响,并通过超临界溶液浸渍法将盐酸多西环素负载到水凝胶中。结果表明:Alg-PBA与PVA质量比为2:1、PVA分子量为77kDa时,可制备机械性能良好的水凝胶,载药水凝胶在体外药物释放中表现出了明显的活性氧(ROS)响应性,为新型水凝胶伤口敷料的制备提供了参考。  相似文献   

9.
采用交替沉积自组装的方法制备聚乙烯醇(PVA)/纳米纤维素(NCC)-纳米TiO2/PVA复合膜,用傅里叶变换红外光谱(FT-IR)和扫描电子显微镜(SEM)表征,结果表明PVA/NCC-纳米TiO2/PVA复合膜形貌规整,NCC负载纳米TiO2粒子只是物理共混,没有化学键合.性能分析结果表明PVA/NCC-纳米TiO2/PVA复合膜在紫外光区有较强吸收,较高的拉伸强度109.5 MPa,且比PVA膜热稳定性好,热分解温度提高约20℃.  相似文献   

10.
采用落锤试验仪对含有加入不同长度PVA纤维的钢纤维混凝土进行落锤冲击试验,得到了掺有不同长度的PVA纤维条件下混凝土试件的拟合力—时间、位移—时间曲线。通过对曲线的分析对比,得出PVA纤维的掺入大大提高了混凝土的抗冲击性能。其中,试验选取的6mm、9mm、12mm、15mm不同长度的PVA纤维中,12mm长度的PVA纤维对钢纤维混凝土的强度和刚度等力学性能提升最大,并且在不同冲击能量下均表现出优于其它长度的特性。  相似文献   

11.
In this paper, Fe-octacarboxyl acid phthalocyanine (Fe-OCAP)/polyurethane (PU) blends were prepared by solution blending. The mechanical and dynamic mechanical properties of the samples were evaluated by tensile tests and dynamic mechanical analysis. The results showed that incorporation of Fe-OCAP significantly improved the tensile strength, elongation at break, and thermal deformation property of PU matrix. The interaction between Fe-OCAP and PU was investigated by infrared analysis. The result indicated that strong hydrogen bond was formed between Fe-OCAP and hard segments of PU and increased with increasing Fe-OCAP content. Quantitive evaluations of the interaction between Fe-OCAP and PU were conducted by analyzing the physical cross-linking density in samples. The results indicated that the physical cross-linking density of the samples was increased with increasing Fe-OCAP content.  相似文献   

12.
采用含水的复合改性剂增塑聚乙烯醇(PVA),制备熔纺PVA纤维原丝。经冷拉伸3倍后,分别在160、220℃下进行热拉伸。研究了拉伸对纤维结构和表面、截面形貌的影响。结果表明:拉伸使纤维分子取向,结晶度升高;熔纺PVA纤维截面为圆形,拉伸后在纤维表面产生沿轴向的微孔,增加了纤维表面的粗糙度。  相似文献   

13.
为探索增强纤维对混凝土性能影响的规律,选用聚乙烯醇(PVA)纤维、超高相对分子质量聚乙烯(UHMWPE)纤维、玄武岩纤维和玻璃纤维增强混凝土制备超高性能混凝土(UHPC)。通过性能测试,选出UHPC改性最佳纤维——PVA纤维和UHMWPE纤维。采用Design-Expert专业实验数据分析软件,对PVA和UHMWPE混杂纤维设计进行理论模拟,针对目标纤维进行掺量优化设计,得出当12 mm长度的PVA纤维的体积分数为0.3%、6 mm长度的UHMWPE纤维的体积分数为0.9%时,目标UHPC的抗折强度、抗压强度与流动度达到最优化设计目标。  相似文献   

14.
To enhance the thermal stability of poly(vinyl alcohol) (PVA) fiber, the fiber was prepared from the gel spinning of high molecular weight (HMW) PVA by using dimethyl sulfoxide/water (8/2, v/v) as a solvent, accompanied with the cross‐link by boric acid (B‐PVA). In addition, the structure and properties of the B‐PVA fiber were compared with those of the HMW PVA fiber obtained by using the same spinning system without cross‐linking (NB‐PVA). Through a series of experiments, it turned out that cross‐linking actualized by an optimum amount of boric acid (0.3 wt % based on PVA) and zone drawing caused significant changes in the properties of HMW PVA gel fiber. That is, cross‐linking increased thermal degradation temperatures at each degradation step and amounts of final residues, resulting in improving thermal properties of the PVA fiber. On the contrary, it was found that in the case of the B‐PVA fiber, some broadening of the original PVA unit cell occurred, which was identified by the peak shift to lower angle in X‐ray diffractogram. The tensile strength and Young's modulus of B‐PVA fiber with draw ratio of 15 are 23.1 and 308.3 g/d, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

15.
以载体法制备出聚四氟乙烯纤维(PTFE)/聚乙烯醇(PVA)初生丝,然后对初生丝进行不同时间的烧结,以除去PVA制得PTFE纤维,对PTFE纤维进行不同程度的拉伸,检测不同烧结时间和拉伸倍数对纤维力学性能的影响。  相似文献   

16.
Electrospun fibers of poly(vinyl alcohol) (PVA) and PVA/poly(4‐styrenesulfonic acid) (PSSA) were obtained. By varying PVA to PSSA weight ratios, various fiber sizes and shapes were observed. The fiber diameters ranged from 176 to 766 nm, and the largest fibers were obtained from 15 wt % aqueous PVA solution. The effect of solution viscosity on fiber morphology was discussed. The presence of PSSA in electrospun fibers was confirmed by Fourier Transform Infrared spectroscopy. The PVA fibers were thermally stable up to 250°C, and the PVA/PSSA fibers were stable up to approximately 150°C. The water stability of the fibers was improved by heat‐treatment at 120°C. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

17.
为了改善酚醛泡沫的性能,选用聚乙烯醇(PVA)纤维作为酚醛泡沫的增强材料,研究了不同PVA纤维含量和长度对酚醛泡沫的泡孔结构、压缩性能、弯曲性能的影响。结果表明,PVA纤维可以有效改善酚醛泡沫的力学性能和泡孔结构,随着PVA纤维含量的增加,酚醛泡沫的力学性能呈现先增大后减小的趋势。当PVA纤维的用量为酚醛树脂质量的3%时,酚醛泡沫的力学性能达到了最大值,泡孔结构达到了小且均匀的状态。PVA纤维的长度对酚醛泡沫的泡孔结构也有一定的影响,当PVA纤维长度为6 mm时,酚醛泡沫具有最好的泡孔结构,但PVA纤维长度增加时,酚醛泡沫的压缩性能、弯曲性能减小。  相似文献   

18.
高性能聚乙烯醇纤维的研究进展   总被引:3,自引:0,他引:3  
综述了高性能聚乙烯醇(PVA)纤维的研究进展;介绍了超高相对分子质量和高立构规整度的PVA 制备方法;详述了凝胶纺丝制备高性能PVA纤维的工艺及其影响因素:纤维结构、拉伸工艺、溶剂、凝固剂种类、凝固浴温度等。展望了高性能PVA纤维的发展动向和应用前景;指出高聚合度、高间规度PVA纤维是其研究方向。  相似文献   

19.
简述了制备高强高模聚乙烯醇(PVA)纤维的原理,阐述了高强高模PVA纤维结构和性能的影响因素。指出合理选择PVA的相对分子质量、支化度、立构规整性、醇解度和纺丝方法,优化控制凝固浴温度、萃取条件、萃取干燥控制条件、高倍拉伸和热处理等,可得到性能优良的高强高模PVA纤维。  相似文献   

20.
PVA/TOCN composite fiber with a weight ratio of 100:1 was prepared from a mixture of aqueous poly(vinyl alcohol) (PVA) solution and 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO)-oxidized cellulose nanofibril (TOCN) dispersion using spinning, drawing, and drying processes. The as-spun PVA/TOCN composite fiber was further drawn, up to a draw ratio of 20 by heating at up to 230 °C. The maximum tensile modulus of the PVA/TOCN composite drawn fiber reached 57 GPa, remarkably higher than that of commercial PVA drawn fibers. Moreover, the PVA/TOCN composite drawn fiber had storage modulus higher than that of the PVA drawn fiber at each temperature in the range from 28 to 239 °C. Structural analyses showed that amorphous PVA regions in the composite drawn fiber were more oriented than those in neat PVA fiber after the addition of the small amount of TOCN used. These results indicate that TOCN elements were individually dispersed in the PVA matrix without aggregation and formed hydrogen bonds with amorphous PVA molecules in the composite drawn fiber.  相似文献   

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