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研究了国产Z30S聚丙烯及其改性切片的分子量(MW)和分子量分布(MWD)以及纺丝工艺对纺制细旦丙纶复丝可纺性和卷绕丝结构性质的影响。研究表明,采用Z30S切片即使纺丝温度高达280℃时,卷绕丝仍是α晶型结构,若添加少量降温母粒共纺或经改性后纺丝,卷绕丝可获得准晶型或混晶型结构,有较好的可纺性和后拉伸性;纺丝工艺条件,诸如纺丝温度、冷却条件、泵供量和纺丝速度等对卷绕丝的结构和性质虽起重要的影响,但PP的MW和MWD则起首要的影响。 相似文献
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《合成纤维工业》2017,(1):17-20
采用熔融纺丝法制备耐高温聚醚砜(PES)纤维,对PES切片的热性能、流变性能以及可纺性进行了研究,并对PES初生纤维的力学性能和表面形貌进行了表征。结果表明:PES具有良好的热稳定性能和较宽的加工温度范围,其起始热裂解温度为530.8℃,适宜熔融纺丝;PES熔体是一种典型的剪切变稀型流体,对剪切速率和温度变化较为敏感;纺丝工艺对PES的可纺性影响显著,PES在100℃干燥6 h,螺杆三区温度分别为330,340,345℃,喷丝板温度345℃,喷丝板压力约2.4 MPa,卷绕速度170 m/min的条件下,PES初生纤维的综合性能优异、纤维粗细均匀、表面光滑。 相似文献
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熔融纺丝法制备聚醚砜纤维 总被引:5,自引:0,他引:5
将聚醚砜(PES)树脂进行熔融纺丝,制得PES纤维,对PES树脂的可纺性、PES纤维的拉伸条件、力学性能、热性能、阻燃性能进行了研究。结果表明:PES树脂在熔融温度380℃,卷绕速度300m/min的条件下,可纺性较好;PES纤维适合在较低温度和较低速度下拉伸,在30℃下低速拉伸,PES纤维可拉伸3倍,其强度可达2.30cN/dtex;PES纤维的热稳定较好,其初生纤维的起始分解温度为442.15℃;PES纤维的阻燃性能较好,极限氧指数为26.9%。 相似文献
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本文介绍了在进口FDY纺丝设备上,用国产聚丙烯切片(MI30左右)纺制细旦丙纶拉伸丝的工艺,同时还研究了纺丝速度,拉伸倍数对纤维性能的影响。结果表明,分子量分布窄的聚丙烯切片纺丝性能良好,卷绕速度为3000m/min时制得单丝纤度为1.88dtex的纤维强度可达3.79cN/dtex。 相似文献
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由于聚丙烯缺乏染色席次,熔体着色成为工业化生产聚丙烯纤维普遍采用的办法。本文通过本色(纯PP)及着色聚丙烯高速卷绕丝的对比研究,揭示了聚丙烯着色熔体高速纺时纤维结构形成的基本规律。色母粒的加入改变了熔体冷却固化过程。使纺丝张力大大提高。在较低纺速下,着色卷绕丝结晶度增强主要归因于次晶的快速生长;在较高纺速下,结晶度增加主要归因于α晶的快速生长。同时,颜料颗粒的存在,不仅减弱了无定形区的大分子缠结和分子间力,而且使结晶区的折叠链结构更趋松散并使缚结分子易从晶片中滑脱。因此,相同纺速下制取的聚丙烯卷绕丝总是具有较低的强度、较低的屈服应力和较大的延伸度。 相似文献
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Melt spinning of metallocene catalyzed polypropylenes. II. As‐spun filament structure and properties
The melt spinning of metallocene catalyzed isotactic polypropylene (miPP) resins was investigated. The as‐spun filament properties from six miPP resins were studied with melt flow rates (MFR) between 10 and 100, and a Ziegler–Natta catalyzed isotactic polypropylene (zniPP) resin with a MFR of 35 was studied for a comparison. Generally, as the molecular weight increased the filament density increased, the birefringence decreased, the tensile strength decreased, and the elongation to break increased. As the spinning speed increased, the density, birefringence, tensile strength, and crystalline and noncrystalline orientation functions generally increased. However, the low MFR miPP and the zniPP resin had decreases in the birefringence and tensile strength with an increase of the spinning speed. The miPP resins were found to have breaking tensile strengths up to 50% higher than the zniPP resin at similar spinning speeds. The observed fiber properties were explained based on the nature and orientation of noncrystalline portions of the fibers. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 3237–3247, 2001 相似文献
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The melt spinning of metallocene catalyzed isotactic polypropylene resins was investigated. The details are presented for on‐line studies performed on six miPP resins with melt flow rates (MFRs) between 10 and 100 and a Ziegler–Natta catalyzed isotactic polypropylene resin with a MFR of 35 for comparison. The on‐line studies indicated that, as the molecular weight and polydispersity increased, crystallization occurred closer to the spinneret at higher crystallization temperatures and under lower spin line stresses. Further, as the spinning speed increased, crystallization occurred closer to the spinneret at higher crystallization temperatures because of increased stress in the spin line. These observations were interpreted in terms of an increased rate of crystallization caused by increased molecular orientation in the spin line with increasing molecular weight and increasing spinning speed. This “stress‐enhanced” crystallization was further interpreted in terms of an increased rate of crystal nucleation. It was further concluded that the narrower molecular weight distribution of metallocene resins was the primary factor that produced differences in the structure and properties of fibers spun from these resins compared to those of Ziegler–Natta catalyzed resins of similar weight‐average molecular weight or MFR. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 3223–3236, 2001 相似文献
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Bahareh Kalantari Ruhollah Semnani Rahbar M. R. M. Mojtahedi S. A. Mousavi Shoushtari Ali Khosroshahi 《应用聚合物科学杂志》2007,105(4):2287-2293
In the present work, effect of selective peroxide on reactor grade polypropylene (PP) (known as V30S) during melt spinning process on the physical and thermal properties of as‐spun resultant multifilament yarn was studied. Attempts have also been made to compare this yarn sample with other fiber samples produced from reactor and controlled rheology grades polypropylene. The results show that the multifilament yarn spun from V30S/Peroxide sample shows higher birefringence and tensile strength and also lower modulus, elongation at break, and shrinkage compared with that of spun from pure V30S granule. Density and thermal behavior studies show low variations compared with original sample. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
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远红外细旦丙纶高速纺丝及变形工艺研究 总被引:4,自引:0,他引:4
探讨了远红外细旦丙纶高速纺丝工艺对其可纺性、纤维结构性能的影响 ,研究了远红外 PP-POY的变形工艺。结果表明 ,研制远红外细旦丙纶长丝最佳的纺丝工艺条件为 :纺丝温度 2 5 8℃ ,纺丝速度小于或等于 2 5 0 0 m /min,侧吹风温度 18℃ ,速度 0 .4m/s,集束上油位置距喷丝板 92 0 m m ;最佳的变形工艺条件为 :第一热箱温度 14 5~ 14 8℃ ,第二热箱温度 12 5~ 130℃ ,拉伸比 1.5 6~ 1.5 8,D /Y比1.66~ 1.69,变形速度 42 0~ 45 0 m/m in。 相似文献
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介绍了高流动性荧光母粒在聚丙烯纤维(PP纤维)生产中的应用情况。结果表明,荧光母粒在PP纤维生产中具有流动改性和增白增艳双功能作用。荧光母粒与PP共混纺丝显示出优良的可纺性,所生产的荧光丙纶外观光亮、鲜艳、柔和,有效地提高了PP的装饰性能。 相似文献