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1.
采用熔融缩聚的方法合成了胍基聚合物(PHGC,PHBG)抗菌剂,应用DSC及热失重研究了抗菌剂的热稳定性,对PA6/PHGC共混体系进行了流变性能分析,纺制了PA6/PHGC纤维,研究了共混纤维的抗菌性能及抗菌剂加入对其他性能及结构的影响。  相似文献   

2.
IntroductionPoly(m-phenyleneisophthalamide)(PMIA)fibers arei mportant materials with excellent ther mal and oxidativestability,flame resistance,and dielectric properties.Thedecomposition temperature of PMIA is400430℃andeven under this temperature it releases little har mful gases.Unlike flame-retardant treated materials,PMIAfibers areinherently flame resistance and it will not di minish duringthe life of the fiber.The fiber s low tenacity and highelongation give it textile-like character…  相似文献   

3.
聚胍修饰抗菌型海水提铀材料   总被引:2,自引:0,他引:2  
通过聚六亚甲基盐酸胍(PHGC)和偕胺肟基(AO)在戊二醛条件下的交联作用,制备出一种具有高效抗菌性的新型海水提铀材料(PAM-AO-PHGC).使用傅里叶转换红外光谱(FT-IR)和扫描电子显微镜(SEM)表征材料表面的官能团和形貌.通过吸附实验研究了不同吸附条件下(pH、盐离子浓度和吸附时间)的铀吸附性能. PAM-AO-PHGC在模拟海水中的平衡吸附容量达到231.0 mg·g~(-1),吸附过程符合准二阶动力学方程.材料在海水pH(8.0)和高盐离子浓度(0.5 mol/L NaCl)的条件下,均表现出优异的铀吸附性能.此外, PAM-AO-PHGC可有效抑制大肠杆菌、金黄色葡萄球菌和海洋中广泛存在的两种弧菌的生长,聚胍的引入有望解决海水提铀材料在使用过程中的生物污损问题.  相似文献   

4.
The rheological properties of two cellulose samples,e.g.Cotton 1 and Wood 2 were investigated,including the dependence of non-Newtonian Index,structure viscosity and zero shear viscosity on concentration and temperature of the solutions.Non-Newtonian Index n decreases with concentration and increases with temperature,structute viscosity increases with concentration and decreases with temperature.Zero shear viscosity decreases in an index manner with temperature and viscose flow activation energy is higher than that of viscose solution.The reactive property of Cotton 1 is better than that of  相似文献   

5.
UHMW-PAN is an important polymer material used to make high strength and high modules fiber as well as hollow fiber membrane with high mechanical strength to resist the backwash process.In this paper, the effect of temperature on non-Newtonian flow index, structural viscosity index,maximum relaxation time and zero shear viscosity of the UHMW-PAN solution has been studied.The relationship between parameters and spinnability has been discussed. On the basis of above works, the suitable temperature of spinning solution by gel-spinning has been found.  相似文献   

6.
The effects of MgO and TiO2 on the viscosity, activation energy for viscous flow, and break-point temperature of titanium-bearing slag were studied. The correlation between viscosity and slag structure was analyzed by Fourier transform infrared (FTIR) spectroscopy. Subsequently, main phases in the slag and their content changes were investigated by X-ray diffraction and Factsage 6.4 software package. The results show that the viscosity decreases when the MgO content increases from 10.00wt% to 14.00wt%. Moreover, the break-point temperature increases, and the activation energy for viscous flow initially increases and subsequently decreases. In addition, with increasing TiO2 content from 5.00wt% to 9.00wt%, the viscosity decreases, and the break-point temperature and activation energy for viscous flow initially decrease and subsequently increase. FTIR analyses reveal that the polymerization degree of complex viscous units in titanium-bearing slag decreases with increasing MgO and TiO2 contents. The mechanism of viscosity variation was elucidated. The basic phase in experimental slags is melilite. Besides, as the MgO content increases, the amount of magnesia–alumina spinel in the slag increases. Similarly, the sum of pyroxene and perovskite phases in the slag increases with increasing TiO2 content.  相似文献   

7.
采用Haake旋转流变仪对尼龙1212-b-聚四氢呋喃(PA1212-b-PTMG)系列嵌段共聚物熔体的动态流变行为进行研究,结果表明:嵌段共聚物样品熔体线性黏弹区缩短,复合黏度对频率响应有Cross方程拟合性,熔体均表现出非牛顿流体的特征,PA1212-b-PTMG熔体动态黏度对温度的敏感性比均聚尼龙1212低,耐热性能下降.  相似文献   

8.
Experimental studies on the rheological properties of a CaO–SiO2–Al2O3–MgO–TiO2–(TiC) blast furnace (BF) slag system were conducted using a high-temperature rheometer to reveal the non-Newtonian behavior of heterogeneous titanium-bearing molten slag. By measuring the relationships among the viscosity, the shear stress and the shear rate of molten slags with different TiC contents at different temperatures, the rheological constitutive equations were established along with the rheological parameters; in addition, the non-Newtonian fluid types of the molten slags were determined. The results indicated that, with increasing TiC content, the viscosity of the molten slag tended to increase. If the TiC content was less than 2wt%, the molten slag exhibited the Newtonian fluid behavior when the temperature was higher than the critical viscosity temperature of the molten slag. In contrast, the molten slag exhibited the non-Newtonian pseudoplastic fluid characteristic and the shear thinning behavior when the temperature was less than the critical viscosity temperature. However, if the TiC content exceeded 4wt%, the molten slag produced the yield stress and exhibited the Bingham and plastic pseudoplastic fluid behaviors when the temperature was higher and lower than the critical viscosity temperature, respectively. When the TiC content increased further, the yield stress of the molten slag increased and the shear thinning phenomenon became more obvious.  相似文献   

9.
采用恒速型毛细管流变仪研究分子量双峰分布聚乙烯PE-SP2520的高速挤出性能.结果表明:因分子量分布的特殊性,PE-SP2520的结晶度和熔峰温度均低于对比样品LLDPE-7047.高速挤出时PE-SP2520剪切黏度较高,非牛顿流动性较弱,入口压力降和熔体强度较高.与对比样品比较,PE-SP2520挤出稳定性好:挤出压力稳定,流动曲线连续,挤出畸变主要为鲨鱼皮畸变.流动稳定性提高的重要原因在于分子量双峰分布使分子链缠结能力下降,熔体/管壁边界应力集中效应弱.  相似文献   

10.
研究了改进型蜡基粘结剂体系和Fe-2Ni粉混合制备的喂料的流变性能.结果表明,喂料是一种假塑性流体,其非牛顿指数n较大,150℃时n为0.52,恒剪切速率粘流活化能△Eη=53.8Kj·mol  相似文献   

11.
实验测定了不同浓度下高分子聚丙烯酰胺溶液在岩芯和流变仪中的流变性,证实了其在多孔介质中流动时存 在“弹性”,且在中等剪切速率范围内(0.1~100.0 s−1)符合非牛顿幂律渗流模式。基于实验取得的认识,利用黏弹性本 构方程表征聚合物溶液有效黏度,建立了黏弹性聚合物驱油藏的不稳定渗流数学模型,利用有限差分方法求得数值 解,研制了相应的无因次试井图版,并对实测试井资料进行了拟合解释,探讨了弹性对聚合物驱油藏试井曲线形态的 影响。研究表明,弹性虽然会造成近井地层压力大幅上升,但几乎不改变试井曲线形态。因而,在黏弹性聚合物驱油 藏试井分析中,可以忽略弹性的影响,应用非牛顿幂律试井模型求取解释参数。  相似文献   

12.
为了进一步加强对稠油蒸汽泡沫驱油过程中流体力学性能的认识,在油藏压力7.60 MPa下,利用高温高压流变仪测得了不同条件下稠油蒸汽泡沫共混体系的流变曲线.实验结果表明:稠油蒸汽泡沫驱油体系均为假塑性流体,其流变方程能很好地关联幂律模型;随蒸汽相饱和度和泡沫剂浓度升高,体系表观黏度增大;随蒸汽干度和温度升高,体系表观黏度降低;在低剪切速率时,表观黏度和温度关系满足Arrhenius方程,随着剪切速率增大,表观黏度和温度关系逐渐偏离Arrhenius方程;黏流活化能的绝对值随剪切速率增大而降低,在低剪切速率时,表观黏度对于温度变化更敏感.  相似文献   

13.
本文研究了不同氯化钠(NaCl)浓度,不同温度下的海藻酸钠(SA)及其与多壁碳纳米管(MWCNTs)复合溶液的流变行为。利用 Ostwald’s 和 Arrhenius 方程计算得出溶液的非牛顿指数和粘流活化能。结果表明,纺丝溶液属于非牛顿流体,溶液的零剪切粘度随着NaCl浓度的增加逐渐增加,非牛顿指数却逐渐降低。MWCNTs 的加入使得SA溶液的粘流活化能降低,说明 MWCNTs 的加入增加了溶液的流动性。  相似文献   

14.
目前绝大多数的油包水型乳状液粘度预测模型都把乳状液视为牛顿流体,而原油包水型乳状液特别是稠油包水型乳状液在中、高含水率时却经常表现出很强的非牛顿性。根据油包水乳状液表现出非牛顿性的机理,考虑了乳状液的非牛顿性与含水率的关系,提出了改进的PR模型,用于预测油包水型乳状液的表观粘度。此方法只需知道纯油的粘温关系、一组高含水率下的剪切率与表观粘度的关系及一个低含水率下的表观粘度值,即可预测各种温度、含水率和剪切率下油包水型乳状液的表观粘度(相对粘度)。对比结果表明,改进的PR模型的预测结果更符合实测结果。  相似文献   

15.
采用DV-Ⅱ+Pro型旋转黏度计分别测试了液体氟碳、氟醚及氟硅橡胶的流变性能。结果表明,在30~45 ℃的范围内,分子量对端羧基液体氟碳橡胶的黏度影响较大;3种液体含氟橡胶在较宽的剪切范围内均为牛顿流体,黏度均随温度的升高而降低,在低温范围内,端羧基液体氟碳橡胶的黏度远远大于液体氟醚橡胶,当温度达到60 ℃以上时,二者的黏度值相差不大,均在20 Pa·sg附近,液体氟硅橡胶的黏度很低,稳定值在5 Pa·s;黏流活化能从大到小依次为端羧基液体氟碳橡胶,液体氟醚橡胶,液体氟硅橡胶。  相似文献   

16.
Ultra-high molecular weight polyacrylonitrile (UHMW-PAN ) was prepared by aqueous suspension polymerization, and the effect of molecular weight on its rheological behaviors hi dimethylsulf oxide (DMSO) and the spinning stability were investigated. It shows that, compared with common polyacrylonitrile ( C-PAN), UHMW-PAN/DMSO solution has smaller non-Newtonian index, larger structural viscosity index, much longer maximum relaxation time, and no first-Newtonian region appears in the flow curves under the same experimental conditions. The explanations for these phenomena are given in the view of chain-entanglements. The optimal technology of preparing UHMW-PAN fibers and hollow fiber membranes could be obtained based on the rheological study.  相似文献   

17.
用聚醚N210,N220和二苯基甲烷二异氰酸酯(MDI)合成了两个系列的聚氨酯预聚体。用旋转粘度计研究了预聚体的流动行为。结果表明:其流动曲线符合Ostwad-DerWaele幂律模型;粘度—温度关系符合Arhenius方程;流动活化能随剪切速率的增加而下降。探讨了预聚体的非牛顿行为、流动活化能和分子结构的关系  相似文献   

18.
采用薄膜叠压法制备玻纤布增强高黏度聚丙烯热塑复合材料,研究了高黏度聚丙烯熔体浸渍玻璃纤维布过程。通过旋转流变测试分析,可知高黏度聚丙烯树脂熔体在浸渍过程中表现为非牛顿流体特性。以达西定律为理论基础,结合材料物性参数和工艺参数,推导了非牛顿流体浸渍玻璃纤维布的浸渍模型。在不同的浸渍压力与存留时间条件下对模型进行实验验证,理论值与实验值基本吻合。利用建立的浸渍模型分析了浸渍工艺对复合材料浸渍过程的影响,结果表明通过升高温度和提高压力等途径可减小浸渍时间。  相似文献   

19.
本文对四种工业用模具钢CrWMn、GGr15、Cr12MoV和3Cr2W8V的超塑性流变曲线、应变速率敏感性指数m值和超塑性流变激活能Q_(SP)值进行了测定,并考察了温度的影响。在此基础上讨论了m值、Q_(SP)值和断裂延伸率之间的关系以及超塑流变的速率控制机理。  相似文献   

20.
高铝钢连铸过程中,为了避免或减轻钢液中Al与保护渣中SiO2发生反应,设计了低SiO2、高Al2O3含量的高铝钢连铸保护渣,通过添加适量的酸性氧化物B2O3协调熔渣酸碱性,利用实验分析了B2O3含量对高铝钢保护渣熔融特性、黏度特性及渣膜传热特性的影响。结果表明,B2O3含量在4%~10%时,随着B2O3含量增加,保护渣熔化温度、黏度、黏流活化能均降低,渣膜热流密度增加;保护渣的等温转变曲线(TTT曲线)向孕育时间增加的方向移动,晶体生长速率降低;实验条件下,增加B2O3含量可抑制保护渣中CaF2的析出。  相似文献   

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