改性丙纶组成与纺丝温度和形态结构关系研究

采用聚丙烯(PP)与不同量的常压阳离子染料可染共聚酯(ECDP)、与同量但组成不同的ECDP混合均匀,应用单螺杆熔融纺丝机进行共混熔融纺丝、拉伸、热定型,制备改性丙纶,研究ECDP含量与组成对改性丙纶纺丝温度和形态结构的影响规律。结果表明:①PP/ECDP共混体系的纺丝成形加工温度随ECDP含量的增加而下降,当ECDP含量达到10%,成形加工温度为190℃。②共混体系的成形加工温度随着ECDP中间苯二甲酸磺酸钠双羟乙酯(SIPE)的增加而降低。当SIPE含量达到5%时,最佳纺丝温度为190℃。③共混体系的可纺性随ECDP中α,ω-二-(4-羟基丁基)聚二甲基硅氧烷(PDMS)含量的增加而提高。而PDMS相对分子质量在本实验范围内对纺丝温度与可纺性的影响不大。④在改性丙纶中,ECDP分散相存在于PP基体中,SIPE含量增加,分散相微粒直径增大;而PDMS的加入则改善了PP与ECDP的相容性,使共混纤维中分散相粒径明显变小。     

DSC法对阳离子染料可染共聚酯热性能的研究

利用差示扫描量热法(DSC)对阳离子染料可染共聚酯即高温高压型(CDP)及常压沸染型(ECDP)的熔融和结晶过程进行了研究。结果表明:无定形CDP的玻璃化转变温度(T_g)、冷结晶温度(T_(ch))高于PET,但其熔点(T_m)低于PET,无定形ECDP的T_g与T_m低于PET和CDP,且随第四单体聚乙二醇(PEG)的含量及相对分子质量((?)_n)的增加而降低,其结晶速率随PEG的(?)_n及含量的增加而增加。对于等温结晶的共聚酯,1,3-间苯二甲酸双羟乙酯-5-磺酸钠(SIPE)的引入及PEG含量的增加,共聚酯的熔融焓(△H_m)及T_m下降;当PEG含量相同时,随PEG (?)_n增加,ECDP的△H_m及T_m均增加。     

常压阳离子可染PET的性能研究

通过PTA-EG-SIPE-PEG四元共缩聚反应制备了常压阳离子可染共聚酯并纺制了纤维。初步探索了不同共聚组分及含量对共聚酯的组成、热性能和流变性能等的影响。探讨了改善共聚酯热性能的途径。结果表明:T-g、T_c随SIPE的加入而升高,T_m则下降。PEG的加入使T_g、T_c下降。但CDP、ECDP的T_m均低于PET。CDP、ECDP的热失重温度均低于PET,且随SIPE、PEG加入量的增加而降低。加入热稳定剂能使CDP,ECDP热稳定性有较大的提高。CDP流动性差于PET,且随SIPE增加而更差。其粘流活化能的顺序为E_η(CDP)>E_η(ECDP)>E_η(PET)。SIPE,PEG的加入使缩聚反应体系的出料率增加。     

共聚酯共混改性丙纶染色动力学研究

以阳离子蓝X-GRRL为染料,根据100℃时,常压阳离子染料可染共聚酯共混改性丙纶在不同时间的上染量,采用无限染浴模型计算染料分子在改性丙纶中的扩散系数,据此求出染色过程的扩散活化能。其结果如下:100℃时阳离子蓝X-GRRL染料在改性丙纶中的扩散系数为1．8×10 -11cm2／s,是丙纶的扩散系数的10 000倍以上;扩散活化能为89．13 kJ／mol。     

醚型阳离子染料可染共聚酯流变性能的研究

研究了醚型阳离子染料可染改性共聚酯(ECDP)的流变性能,与阳离子染料可染共聚酯(CDP)及聚对苯二甲酸乙二醇酯(PET)进行了比较。结果表明:ECDP属于切力变稀流体。在相同温度和剪切速率的条件下,与PET相比,CDP熔体的表观粘度(ηa)增加,ECDP的ηa下降;随着第四单体聚乙二醇含量的增加,ECDP的ηa、粘流活化能及结构粘度指数均下降,而非牛顿指数增加,流动性增强,可纺性得到改善。     

PLA/P34HB共混纤维的制备与性能

采用熔融纺丝法制备了聚乳酸（PLA）/聚（3-羟基丁酸酯-co-4-羟基丁酸酯）（P34HB）共混纤维,分析了P34HB含量对PLA/P34HB共混纤维热学性能、结晶性能和力学性能的影响,并研究了拉伸倍数对P34HB含量为30%(w)的共混纤维性能的影响。结果表明：当拉伸倍数为3倍时,随着P34HB含量的增加,PLA/P34HB共混纤维的结晶度逐渐降低,断裂强度和初始模量逐渐下降,而断裂伸长率逐渐增大;随着拉伸倍数的增大,P34HB含量为30%(w)的PLA/P34HB共混纤维的结晶度、断裂强度和初始模量逐渐提高,断裂伸长率逐渐降低,当拉伸8倍时,共混纤维的断裂强度达到425 MPa,断裂伸长率为15.5%,初始模量为7 005 MPa。     

ECDP/PTT共混物相容性及流变性能研究

研究了易染阳离子染料可染聚酯(ECDP)/聚对苯二甲酸丙二醇酯(PTT)共混物的相容性及其流变性能。结果表明:ECDP/PTT共混物在无定形区相容性良好,在晶区晶相分离;ECDP/PTT共混物在剪切速率为102~105s-1时属于切力变稀流体;纺丝温度245℃时,ECDP/PTT共混物具有良好的可纺性,ECDP/PTT质量比为60/40时,所得纤维断裂强度最低。     

染色改性共聚酯的可纺性及其纤维结构性能研究

在聚对苯二甲酸乙二醇酯(PET)分子链上分别引入聚醚、间苯二甲酸乙二醇酯-5-磺酸钠(SIPE)、脂肪酯类,得到染色改性共聚酯(简称共聚酯);将共聚酯进行纺丝、拉伸,制得共聚酯纤维,讨论了共聚酯的可纺性;利用差示扫描量热分析仪、X射线衍射(XRD)仪等研究了共聚酯纤维的结构与性能。结果表明:通过纺丝工艺调整,共聚酯均具有良好的可纺性能;与PET的XRD光谱相比,共聚酯3个主晶面■的衍射峰位置基本没有改变;相比PET纤维,共聚酯纤维的取向度和结晶度以及断裂强度和伸长率有不同程度的下降,而沸水收缩率上升;单体SIPE和柔性链的加入明显改善了共聚酯纤维的染色性能,其上染率和染色深度(K/S值)显著提高,其中醚型和酯型常压阳离子染料可染共聚酯的上染率均大于97%,K/S值均大于28。     

PET共聚酯的热性能及其纤维的力学性能

直接酯化法合成了一系列聚对苯二甲酸乙二酯(PET)-间苯二甲酸双羟乙酯磺酸钠(SIPE)-聚乙二醇(PEG)共聚酯,以差示扫描量热分析法(DSC)研究了这些共聚酯及纯PET的熔融和结晶过程,并利用万能材料测试仪研究了纤维的力学性能。试验结果表明:加入SIPE和PEG后,共聚酯熔点(Tm)、玻璃化转变温度(T)g降低;随着PEG相对分子质量的增大,PET共聚酯的Tg、冷结晶温度(Tc)c、Tm、结晶温度降低(T)c,纤维的断裂强度和初始模量下降,断裂伸长率增加。     

舒适性聚酯纤维研究Ⅲ.共混改性聚酯纤维染色性能

共混改性聚酯纤维由于加入了含有磺酸基团的间苯二甲酸双羟乙酯-5-磺酸钠(SIPE)成分的添加剂,具有较好的阳离子染料可染性能,且阳离子染料的上染率在较大程度上取决于改性添加剂含量的高低。但对分散染料的上染率而言,添加量的影响并不显著。不论何种染料,纤维横截面的变化对于上染率的影响均不明显。碱处理后共混改性聚酯纤维对阳离子染料的吸收量有较大的增加,只不过达到一定程度后,上染率转而趋向下降。但对分散染料而言,其上染率基本上随减量率的增加呈现单一的下降趋势。     

阳离子易染共聚酯的热性能研究

在半连续大装置上合成了含第三单体间笨二甲酸乙二脂-5-磺酸钠(SIPE),第四单体聚乙二醇(PEG)的阳离子易染共聚酯(ECDP);采用热失重分析、差示扫描量热法对ECDP的热性能进行了研究,并对ECDP切片干燥和熔融过程的特性粘数降进行了测试.结果表明:随行PEG含量的增加,ECDP的热分解温度下降,玻璃化转变温度相...     

云母填充改性聚丙烯的研究

对云母填充改性聚丙烯（PP）的研究结果表明，随填充量增加，改性PP的模量明显提高，硬度提高，成型收缩率下降，但强度略有下降，熔体粘度增大，20％（重量）填充量时的综合性能最佳。云母在PP的毕吕起异相成核作用。     

Physical modification of polypropylene. III. Novel morphology of polypropylene and poly(ethylene-co-vinyl alcohol) with epoxy blend fibers

In this study, the novel morphology of polypropylene (PP) and poly(ethylene-co-vinyl alcohol) (EVOH) blend fibers is described. More precisely, the blend fibers of PP–EVOH containing a small amount of EVOH (1, 3, 5, 7, and 9% by weight), with and without epoxy (1 wt %), have been melt-spun at a constant spinning velocity (500 m/min). For the as-spun fiber, both the initial modulus and the tenacity increased with the increase in the EVOH content. The blend fibers with three draw ratios (2, 3, and 4) drawn at room temperature. The scanning electron microscopic study showed that a draw ratio of 2 reveals little about the morphological changes, whereas a draw ratio of 4 showed a streak structure perpendicular to the fiber axis for PP–EVOH (91/9 wt %) blend fibers. In addition, epoxy (1 wt %) containing PP–EVOH (91/9 wt %) blend fiber showed latitudinal streaks. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 1049–1057, 1999     

Physical properties of poly(vinyl alcohol) fibers prepared from wet spinning/multi-step drawing

The preparation of poly(vinyl alcohol) (PVA) fibers by multi-step drawing was examined. The high draw ratio was attained when the drawing just before melting point was repeated. The influences of the draw ratio on mechanical and thermal properties of the fibers were studied. We utilized the wide angle x-ray diffraction (WAXD) as a medium to observe the erystallinity and the orientation of PVA fibers to study their effects on the physical properties of the fibers. With various coagulation bath concentration, both the tenacity and Young's modulus of fibers would increase as the draw ratios increased, the elongation would decrease at the same time. The tenacity was able to reach 41.0 cN/tex with the Young's modulus being 856.2 cN/tex; also, as the draw ratios increased, both crystallinity and orientation would increase. The crystallinity was about 67.2 % and the orientation was about 86.4%.     

蓄热调温聚丙烯腈纤维的制备及性能研究

将石蜡相变微胶囊(MEPCM)添加到聚丙烯腈(PAN)的硫氰酸钠纺丝液中,通过湿法纺丝制备了蓄热调温PAN纤维,考察了MEPCM质量分数对纺丝液可纺性和纤维力学性能、热学性能及染色性能的影响。结果表明:随着MEPCM质量分数的增加,纺丝液表观黏度下降,PAN纤维的蓄热调温能力增大,纤度增大,密度减小,断裂强度和断裂伸长率下降,热分解温度略有降低;对阳离子红5GN的恒温染色速率常数增大,平衡上染量减小,半染时间缩短。     

Structure and tensile properties of Nanoclay–Polypropylene fibers produced by melt spinning

Nanocomposite fibers of polypropylene and montmorillonite‐based organoclay were produced by a melt‐spinning process, and their structures and mechanical properties were studied. The addition of nanoclay in polypropylene increased the rate of crystallization and altered the microstructures of the fibers. Increases in the crystal size and a reduction in the molecular orientation were observed in the nanoclay–polypropylene composite fibers. The tensile properties of nanoclay composite fibers were also studied, and decreases in the fiber modulus and tenacity and increases in the strain at break were observed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Effect of spinning speed on the structure and physical properties of filament yarns produced from used PET bottles

In the previous work (S. Kiantash, MS Thesis, Amirkabir University of Technology, Textile Engineering Department, Tehran, Iran, 2002), the possibility of producing filament yarns from used PET bottles was investigated and the production was successfully carried out. To improve physical properties and to have a detailed understanding of the molecular structure, spinning variables such as the take‐up speed (one of the most influencing factors) should be varied and studied. In the present work, continuous filament yarns from virgin PET chips and used PET bottles were produced at the two take‐up speeds of 2500 and 3000 m/min. Optical birefringence, crystallinity (obtained from three methods including density, calorimetry, and FTIR), tenacity, breaking elongation, initial modulus, and shrinkage of yarns were measured and compared. Optical birefringence and crystallinity (obtained from all three methods) of used samples show higher values compared with those of virgin samples produced at both take‐up speeds. Consequently, the tenacity of used samples is higher and breaking elongation is lower. Generally, samples having bigger crystallinity present higher initial modulus and smaller shrinkage. However, results of initial modulus and shrinkage do not correspond to this assumption. As it was predicted, increasing the take‐up speed resulted in an increase in the optical birefringence, crystallinity, tenacity, and initial modulus and a reduction in the breaking elongation of both virgin and used samples. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3972–3975, 2007     

Mechanical Properties of i-PP/AI Composites

Mechanical properties such as tensile, flexural, and impact behavior of Al powder-filled polypropylene composites were studied in the composite composition range 0–10 vol% Al. Tensile strength, modulus, and breaking elongation decreased with increase in filler content due to the formation of weak structure. Analysis of tensile strength data demonstrated the introduction of stress concentration into the structure. Flexural strength and modulus increased with filler content due to increase in rigidity. Izod impact strength at first increased up to a critical Al concentration, beyond which the value decreased.