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1.
本文利用动态内应力仪对各种纺速和纤度的涤纶POY进行拉伸试验。研究不同纺速、纤度及拉伸条件下POY的动态内应力变化规律,并对制取样品的结晶度、声速、双折射、热收缩率和色差等进行测定。试验表明:(1)纺速为3000~3300m/min的POY动态内应力最低;(2)纤维的色差值随动态内应力波动值增大而增加;(3)纤维的热收缩率取决于超分子结构参数——结晶度与取向度。它随大分子取向度的增加而增大,随结晶度的增大而下降。用二元回归的数理统计方法得到热收缩率和纤维的结晶度以及表征大分子取向的声速、双折射间的定量关系:Y=67.5999+0.3225X_1-3.2430X_2 R=0.9985(纺速1100m/min~5500m/min)式中:Y——纤维的热收缩率;X_1——纤维的双折射;X_2——纤维的结晶度;R——全相关系数。Y=21.4447+1.8558X_1-10.3050X_2 R=0.9993(纤度45dtex/24f~167dtex/30f)Y=10.2246+2.2030X_1-26.2679X_2 R=0.9916(拉伸倍数1.4~2.2)X_1——纤维的声速值。  相似文献   

2.
Using brighten white and modified PET chips, fine denier hollow fibres (dpf=0.5~1.5) were prepared on a Fuji Filter MSTC-400 and VC-443A drawn machine, whose structure and properties were tested by X-ray diffraction mater, SOM-II sonic velocity meter and Instron-1122 Tensile tester, electron and light microscopy etc,. The results show: fine denier hollow taken-up yarns prepared at low spinning velocity have radial orientation, higher strength and elongation at rupture because radial stress is higher than normal stress. Fine denier hollow drawn yarns with hollow degree up to 18~35% and high tenacity, together with high crystalline degree and small crystal and amorphous domains, can be empolyed as products.  相似文献   

3.
In this paper the influences of the drawing temperature on physical structures and properties of PET filaments have been studied. The results show that the temperatures of the first-stage drawing will have significant effects on birefringence development of filaments during the second stage drawing, as well as the oriented amorphous filaments change to crystanine-oriented filaments after heat treatment. Increasing temperature of the second-stage drawing can be greatly increasing the crystallinity and decreasing the dry heat shrinkage of the filaments.  相似文献   

4.
在湿纺成形过程中,拉伸工艺的选择直接影响纤维结构特征的变化。观察芳香含氯聚砜酰胺纤维结构性能对拉伸倍率和温度的依赖性。实验结果表明,随拉伸倍率的增加,大分子链的取向和结晶呈线性增加。在拉伸过程中结构发生了变化,纤维的强度和分解温度亦相应地提高。拉伸温度对结构性能的影响却有不同的规律。随拉伸温度的升高,取向的变化呈双峰现象,这与在四个温度区域下的纤维超分子结构的变化和链段松弛程度有关。纤维的强度、分解温度与拉伸温度的变化规律与取向的变化趋势相一致。结晶随拉伸温度的升高而增加。  相似文献   

5.
常压阳离子染料易染共聚酯纤维微观结构与性能   总被引:2,自引:0,他引:2  
采用红外光谱分析和X射线衍射法,表征常压阳离子染料易染共聚酯(ECDP)纤维的微观结构,并通过测试ECDP纤维和聚酯(PET)纤维的拉伸性能、吸湿性能和导电性能,探讨了微观结构对纤维性能的影响.结果表明:ECDP纤维中第三组分间苯二甲酸5磺酸钠的加入使结晶度减小,因此,断裂强度和初始模量比PET纤维小,而断裂伸长率有所增加,回潮率较大,体积比电阻较小.  相似文献   

6.
本文采用了广角X光衍射、差示扫描量热法、扫描电子显微镜技术,对热熔粘合聚丙烯熔喷非织造布的结构和形态进行研究。讨论了粘合温度对非织造布的几何尺寸和机械性能的影响。结果表明,球晶是熔喷聚丙烯纤维的主要结构形式。在不同的热粘合条件下,球晶的结晶变体中可以出现α晶,或是拟六方酝晶,以及两者的混合形式。粘合温度对纤维的结晶度和晶粒尺寸,及非织造布的热收缩和厚度具有较大的影响。热粘合温度在软化点出现非织造布强度峰值。  相似文献   

7.
Many properties of polyester filaments such as heat shrinkage, tenacity, elongation at break and etc. are greatly influenced by drawing, so post-drawing is important in downstream processing. As more and more profile fibers and multi-variance fibers used in textile industry, the properties of above two kinds of differential polyester filaments after drawing in different heat conditions were studied. Finally following conclusions were obtained: Firstly, the tenacity and elongation at break decreases with the rise of Tp. Secondly, the tenacity rises but the elongation at break decreases with the increase of Tb. Then, when the Tb is low, both the shrinkage in boiling water and hi hot air decreases with the rise of Tp, while, when the Tb is high, both the shrinkage rises with the rise of Tp. The last, both the shrinkage decreases with the rise of Tb.  相似文献   

8.
测定了聚酯复丝内各根纤维和一根纤维的线密度、强度以及断裂伸长 ,并利用Weibull分布模型分析了复丝内各根纤维和一根纤维的强度分布 .得出 :复丝内各根纤维间和一根纤维的断裂强度不匀基本相同 ,都小于断裂伸长不匀 .聚酯复丝中单纤维的强度较好地符合Weibull分布 ,同时存在斜率变化现象 .  相似文献   

9.
聚酯复丝中纤维的强伸度及其分布   总被引:1,自引:0,他引:1  
测定了聚酯复丝内各根纤维和一根纤维的线密度、强度和断裂伸长,并用Weibull分布模型分析了复丝内各根纤维和一根纤维的强度分布。结果表明:复丝内各根纤维间和一根纤维的断裂强度不均基本相同,都小于断裂伸长不均。聚酯纤维的强度较好地符合Weibull分布,且也发现存在变化现象。  相似文献   

10.
The common PP chips have been used to prepare high shrinkage PP fibers with shrinkage in boiling water higher than 50%. Meanwhile, the process conditions on fiber structure and properties have been discussed in detail. With the increase of drawing temperature, the shrinkage in boiling water of the fiber increases at first, and then decreases in the temperature range from 70℃to lOO℃. The better drawing temperature is from 75℃ to 85℃ according to the melt index of the PP material. The shrinkage in boiling water of PP fiber increases with the increase of pump delivery. The orientation factor and crystallinity increase with the increase of drawing temperature. With an increase in drawing temperature, unit-cell numbers and monomer unit numbers in every crystal nucleus tend to increase, but unit volume crystal nucleus tend to reduce.  相似文献   

11.
通过宏观和微观两方面研究聚乙烯冻胶丝条在萃取超拉伸过程中的分子结构变化发现:超拉伸过程诱发和促进了大分子伸直链结构的形成。借助测定纤维热性能口赖曼(Raman)光谱图等来探索和描述纤维在萃取超拉伸过程中的结构及性能的变化,由此提出聚乙烯冻胶纤维萃取超拉伸四阶段变化模型。  相似文献   

12.
Modified polyester fibers were obtained using 2% and 6% of kaolin blends through melt spinning.The influences of two thermal treatments maintaining the original tension(180 ℃×2 min and 200 ℃×1 min)on the structure and properties of fiber were compared.The changes of grain size and crystallinity of fiber were investigated by X-ray diffraction(XRD).The changes of thermal properties of fibers were analyzed using dynamic mechanical analyzer(DMA).The results show that the crystalline structure of kaolin modified polyester fiber doesn't change with the thermal treatment.With the kaolin content increasing,the grain size of fiber changed.The higher the thermal treatment temperature is,the higher the crystallinity of fiber is.There are two glass-transition temperatures for kaolin modified:the lower one is the glass-transition temperature of polyester fiber matrix,and the higher one is derived from the heterogeneous blend of polyester matrix and nano kaolin.The higher the kaolin content is,the higher the glass-transition temperature is.Thermal treatment could increase the compatibility of polyester matrix and nano kaolin.There was only one glass-transition temperature for the thermal treatment fiber,and the heat resistance of fiber was improved.Thermogravimetric analysis-differential scanning calorimetry(TGA-DSC)results of kaolin modified polyethylene terephthalate(PET)matrix indicate that the decomposition temperature of PET fibers,kaolin modified PET fibers,and thermal treated fibers were little different within 40%-60% of weight loss rate range.  相似文献   

13.
针对目前混纤丝异收缩性能表征中存在的问题及异收缩混纤丝的发展趋势,对一步法POY(预取向丝)/FDY(全拉伸丝)涤纶异收缩混纤丝在不同处理条件下的热收缩性能进行系统测试分析.结果表明:一步法POY/FDY涤纶混纤丝经30min沸水处理后测得的收缩率S1可作为其中POY组分收缩率;一步法POY/FDY涤纶混纤丝经80℃、30min定长水定形后的干热收缩率S2可作为其中FDY组分收缩率;两者差值ΔS=S1-S2即为混纤丝的异收缩率.以此提出了一种简便而有效地表征一步法POY/FDY涤纶混纤丝异收缩性能的方法.  相似文献   

14.
本文对在1985-1987年间舟山近岸采集的鳓鱼雌雄个体性状作了比较分析。结果表明:除了吻长、叉长/体长等指标在雌雄间有显著差异外,其它指标均无显著差异。到了繁殖早期,雄鱼的体厚、成熟系数都显著地大于雌鱼,而肝指数却显著地小于雌鱼。本文还进一步用逐步判别的方法给出了鉴别雌雄的判别函数:y_1=-634.8805+137.4845x_1+907.1598x_2+745.8363x_3y_2=-623.6298+123.6892x_1+894.3340x_2+766.0166x_3式中x_1为吻长/头长,x_2为叉长/体长,x_3为体厚/体高,用46个样品回代进行判别,得错判率为10.9%  相似文献   

15.
研究了热牵伸和热定型处理对静电纺丝左旋聚乳酸平行纳米纤维膜力学性能和微观结构的影响。拉伸试验表明,在100 ℃热空气条件下,沿纤维排列方向上牵伸300%、热定型10 min的纤维膜力学性能最佳,其抗拉强度和模量分别达到103 MPa和1.83 GPa。扫描及透射电子显微镜观察显示,经热牵伸后,纤维的直径随牵伸率的增加而减小,其致密及平行程度相应提高,纤维内部转变为垂直于纤维轴且平行排列的片晶结构。差示扫描量热分析结果表明,纤维膜的结晶度随牵伸率的增加而增大,随热定型时间先增加后减小。广角X射线衍射和小角X射线散射分析可知,纤维膜经热处理后的结晶为α型,其微晶尺寸及晶面间距均随牵伸率的增加而减小,随热定型时间先增加后减小,而纤维内部的针状微缺陷随着牵伸率的增加而变得更加狭长有序,使得纤维膜的力学性能得以提高。  相似文献   

16.
本文建立 Mitrinovic—Djokovic 型的不等式的一种推广,特别情形正是[1]中的命题。  相似文献   

17.
聚丙烯腈预氧化纤维(以下简称PANOF)是碳纤维生产过程中的中间产品,其性能的好坏与最终产品碳纤维的优劣密切相关。本文采用热机械分折(TMA)、热失重分折(TGA)、溶胀差示扫描量热分折(SDSC)、X光电子能谱分折(XPS)等实验方法研究了铜盐对PANOF的增强作用。发现Cu~+与PANOF中未环化的氰基有着强烈的相互作用。经铜盐处理后所制得的PANOF,其强度可增加30%。研究结果表明,PANOF得以增强的原因是由于发生了以Cu~+为中心离子,PANOF作为配位体的络合作用。络合配位键的生成使未环化的氰基得以交联,交联网络的形成使PANOF的强度明显提高。  相似文献   

18.
Polyacrylonitrile preoxided fibre PANOF is an intermediate in carbon fibre preparation. Thequality of PANOF is closely related to the property and structure of carbon fibre. In this paper, thermal mechanical analysis(TMA), thermogravimetric analysis(TGA), swell-ing differential scanning calorimetry(SDSC)and X-ray photoelectron spectroscopy(XPS)wereused to study the increase in tenacity of PANOF from the precursor treated with cuprous salt It has been discovered that the cuprous salt reacts strongly with the uncyclized CN of PANOF,resulting in an increase in the tenacity of PANOF by 30%. The results shwo that the cause of thistenacity improvement is the formation of coordinated complex. Cu~+is the central ion, and PANOFthe ligand. It is due to the coordinate bond that the network structure is formed from uncyclizedCN of PANOF. Therefore the tenacity of PANOF is remarkably increased.  相似文献   

19.
人发和牦牛毛的性能测试分析   总被引:1,自引:0,他引:1  
本文对人发和牦牛毛的细度、强伸度、弹性模量、断裂功等物理机械性能进行了较为系统的测定,同时采用扫描电镜、红外光谱等近代测试方法对人发纤维性能与微观结构间的关系作了初步探讨。人发与牦牛毛相比,人发纤维粗而均匀、表面鳞片细密、具有更高的强度与模量及高的胱氨酸含量等特性,这是使人发的硬挺度、坚韧性和弹性等性能优于牦牛毛的主要原因,也是人发黑炭衬优于牦牛毛黑炭衬的原因。  相似文献   

20.
PA6/PET bicomponent fiber at different spinning speeds were produced. Influences of cross blowing, spinning speed, PA6 and PET component ratio, drawing condition etc. on the mechanical properties, heat shrinkage, orientation and crystallization of the fiber were investigated. Also the rules among these influencing parameters were obtained. The splitting property of the fiber and its influence on the textile processing are discussed, which offers a base for the production of PA6/ PET bicomponent fiber using splitting technology.  相似文献   

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