HDPE/LLDPE/CaCO3共混物注射成型收缩率的研究

研究了高密度聚乙烯（HDPE）／线性低密度聚乙烯（LLDPE）共混物及其碳酸钙（CaCO3）填充体系的注射成型收缩率，分别用示差扫描量热仪（DSC）和AR2000高级流变仪分析测定了共混物的结晶度和熔体黏度，并探讨了不同配比下共混物结晶度和熔体黏度与成型收缩率的关系。结果表明，在加工条件不变的情况下，HDPE／LLDPE共混物成型收缩率受结晶度和熔体黏度的显著影响。随LLDPE用量的增加，收缩率的变化明显分为三个阶段，先迅速增大，然后变化减缓，最后又逐渐减小。加入少量铝酸酯活化的CaCO3可以显著降低共混物的成型收缩率。     

聚砜／聚苯硫醚共混物的动态黏弹行为及力学性能研究

研究了聚砜/聚苯硫醚（PSF／PPS）共混物的动态流变特征、共混物动态热力学行为及力学性能，并分析了相容性与力学性能的关系。结果表明，PPS的加入显著改善了共混物的流动性，共混物的黏度随PPS含量和温度的上升而下降，对剪切速率的变化不敏感；共混体系呈一定界面相互作用的两相体系，其相容性依赖于组成比例。当PSF/PPS为3／7（质量比，下同）时共混体系相容性最好，相应地表现出最好的综合力学性能，尤其是冲击强度比PPS提高了64％。     

黏度对环氧树脂基复合微发泡材料结构的影响研究

采用不同黏度的环氧树脂基共混材料,通过模压成型方法制备出系列环氧树脂基复合发泡材料.对发泡材料的泡孔结构进行了观察测量,研究了环氧树脂基共混物黏度对其发泡质量和行为的影响,结果表明:环氧树脂基共混物预处理黏度是影响环氧树脂基复合发泡材料质量的重要因素,共混物预处理黏度是控制环氧树脂固化和泡孔形核长大过程协调性的重要因素,实验范围内,当共混物预处理黏度在12.9 Pa·s时,制备出泡孔平均直径为48μ m、泡孔密度为2.25×107个/cm3、泡孔尺寸均匀的微孔环氧树脂基复合材料.     

PA6相对黏度对PA6/POE-g-MAH共混物缺口冲击性能的影响

研究了尼龙(PA)6相时黏度对PA6/马来酸酐接枝乙烯-辛烯共聚物(POE-g-MAH)共混物缺口冲击性能的影响.结果表明,PA6的相对黏度对PA6/POE-g-MAH共混物的缺口冲击断裂韧性有明显影响;低黏度PA6/POE-g-MAH共混物冲击断裂过程中的裂纹扩展功明显高于中、高黏度PA6/POE-g-MAH共混物;...     

超临界二氧化碳在聚合物共混中的应用

概述了超临界二氧化碳(SC-CO2)在聚合物熔体中的溶解度,SC-CO2对熔体黏度和共混物两相间黏度比以及界面张力的影响,介绍了SC-CO2对聚合物共混物微观形态的影响。     

HDPE/HDPE-g-MAH/PA11共混物流变行为的研究

以马来酸酐接枝高密度聚乙烯(HDPE-g-MAH)为增容剂,通过熔融共混法制备了HDPE/HDPE-g-MAH/聚酰胺11(PA11)共混物,讨论了增容剂HDPE-g-MAH对共混物流变行为的影响。结果表明:HDPE-g-MAH的加入使共混物熔体对剪切速率的敏感性增强,同时使共混物黏度对温度变化的敏感程度减弱;随着HDPE-g-MAH含量的增加,共混物表观黏度先增加后减小,其含量为2%时共混物黏度最大。     

ABS/PC共混物的转矩及毛细管流变行为

采用转矩流变仪和毛细管流变仪研究了丙烯腈-丁二烯-苯乙烯(ABS)/聚碳酸酯(PC)共混体系的流变行为,研究共混物组成对熔体流变行为的影响.结果表明:转矩流变仪中,平衡温度随着转速提高而增大,平衡转矩会在某一转速下达到峰值.两种测试方法得到的流变数据基本一致,共混物熔体呈现剪切变稀的假塑性流体特性.随着PC含量的增加,共混物的表现黏度逐渐增大,共混物熔体的非牛顿指数表现为负偏差,黏流活化能则表现出正负偏差,说明ABS与PC间具有一定的相容性.     

胶原蛋白与壳聚糖相容性研究

将胶原蛋白与两种去乙酰度（95％,85％）的壳聚糖分别配成不同质量比的HAc共混溶液,在28℃下测定了共混液的黏度,利用Δb法则比较共混液中两种物质的相容性。结果表明在28℃的HAc溶液中,任何质量比的胶原蛋白和壳聚糖均相容,并且两者相容性不受壳聚糖去乙酰度的影响。     

共混时间对UHMWPE/LDPE共混物的流变性能及力学性能影响研究

通过熔融共混技术制备得到超高摩尔质量聚乙烯(UHMWPE)/低密度聚乙烯(LDPE)共混物,研究了共混时间对共混物的微观形态、流变特性和力学性能的影响。结果表明,随着共混时间的增加,UHMWPE和LDPE相容性得到明显改善,同时共混物的断裂伸长率显著增加,但UHMWPE/LDPE(50/50)共混物的表观黏度逐渐升高,流动性能下降。     

双峰/单峰高密度聚乙烯共混物的动态流变行为

使用旋转流变仪研究了一种双峰高密度聚乙烯(HDPE)和单峰HDPE共混物在熔融状态下的动态流变行为,探讨了共混物的动态流变行为随不同组分含量、温度以及角频率的变化规律,并分析了共混物的相容性。结果表明:随着角频率的增加,双峰HDPE、单峰HDPE及其共混物熔体的复数黏度均呈现下降趋势,表现出假塑性流体的剪切变稀行为。共混物的零剪切黏度随单峰HDPE质量分数的升高出现了正偏差。所有样品的时温叠加主曲线在低频区未出现特殊的黏弹松弛行为,Cole-Cole曲线变化趋势一致,未出现相分离特征,说明双峰HDPE与单峰HDPE之间具有较好的相容性。     

大庆乙烯装置新区急冷油系统减粘技术的应用

通过对大庆乙烯装置新区急冷油系统在减粘技术方面的研究，控制了急冷油在195～230℃高温段的粘度，为急冷油系统的粘度控制提供新的思维和方法。     

渣油降粘技术

就目前在渣油燃料的运输、储存和加工中所面临的问题一如何降低粘度,综述了5种方法：升温降粘法、稀释降粘法、乳化降粘法、聚合物降粘法和降粘新方法。升温降粘法和稀释降粘法属于物理降粘,乳化降粘法、聚合物降粘法和降粘新方法属于化学降粘。介绍了相关文献,指出开发渣油降粘技术的另一课题：如何解决室温输送。提出渣油降粘开发的新思路：综合使用各种降粘技术,参考稠油降粘的一些工艺,并综合渣油自身的特点开发复合降粘技术。     

混炼胶门尼粘度的预测

使用微机控制系统,采集混炼过程的功率、填充系数等参数,建立数学模型,实现了对混炼胶粘度的预测。其预测结果与实测值比较平均差为１．３６个门尼值,预测值和实测值之间的平均相对误差为２．３６％,此外经过检验,证实笔者所建的预测模型是较稳定的,因此具有实用价值。     

减粘塔减粘技术在乙烯装置上的应用

分析了传统的急冷油减粘方法的不足之处,阐述了减粘塔减粘的原理,并结合减粘塔的工艺特殊性,列举了具体的设计改进、工艺调整以及安全运行防堵措施。介绍了中国石化扬子石油化工股份有限公司烯烃厂1#、2#乙烯装置减粘塔运行情况与效果,并针对遗留问题,提出了改造方案。     

VISCOSITY OF GLYCEROL AND ITS AQUEOUS SOLUTIONS MEASURED BY A TANK-TUBE VISCOMETER

In this paper we demonstrate several series of experiments for the measurement of viscosity of neat glycerol and its aqueous solutions using a tank-tube viscometer. Measuring viscosity of highly viscous liquids with the tank-tube viscometer is easier than other types of viscometers. This inexpensive viscometer continuously generates numerous reproducible viscosity data of highly viscous neat glycerol and its aqueous solutions under given experimental conditions such as a desired temperature and a desired concentration of water in aqueous glycerol solutions.

Fabricating the tank-tube viscometer is inexpensive, since this viscometer does not need sophisticated accessories such as a high-pressure liquid pump, a sensitive pressure sensor, and an accurate flow meter. The tank-tube viscometer consists of a large-diameter reservoir and a long, small-diameter, vertical tube.

The viscosity equation was developed under the following assumptions. Both the quasi steady state approach and the negligible friction loss due to a sudden contraction between the reservoir tank and the tube are valid. The kinetic energy of the emerging stream from the bottom end of the vertical tube of the tank-tube viscometer also is assumed to be negligible. Very viscous glycerol and its aqueous solutions were used to test the viscometer by comparing viscosity values from the viscometer with those from literatures.

The main objective of this study is to demonstrate effects of water as well as temperature on viscosity of aqueous glycerol solutions, applying experimental data of accumulated amounts of aqueous glycerol solutions at various drain durations to the newly-developed viscosity equation for the fabricated tank-tube viscometer.     

甲醇柴油微乳液制备及稳定性的实验研究

复配油酸,二乙醇胺,span80,op-4四种表面活性剂,将其加入到加甲醇柴油混合体系中,制备甲醇柴油微乳液,并采用正交试验方法与粘度指数法,考察了制备温度,搅拌时间,搅拌速度,助表面活性剂用量,甲醇含量5种因素对甲醇柴油微乳液稳定性的影响程度。实验结果表明,当m(油酸)/m(二乙醇胺)/m(span80)/m(OP-4)=10∶2∶3∶2时,可增溶甲醇量最大,正交试验结果表明:样品粘度指数最小,50℃恒温前后的粘度变化最小,为稳定性最佳的甲醇柴油微乳液配方,显著性检验结果表明影响因素作用程度依次为:甲醇含量制备温度搅拌时间助剂用量搅拌速度。在试验温度为30℃,搅拌时间为12 min,搅拌速度为300 r/min时,添加甲醇质量分数为5%的实验条件下制备甲醇柴油微乳液。     

天然橡胶环保改性剂ORA-100的应用

在橡胶产品的生产过程中,特别是轮胎生产过程中,须大量使用天然橡胶。这个过程中遇到的一个棘手问题就是在天然橡胶的停放过程中,生胶的门尼黏度会显著地升高,从而影响天然橡胶的加工性能,增加生产能耗。同时天然橡胶在塑炼,混炼、硫化等生产过程中会产生浓重的气味,这种气味不利于生产企业的环保要求,也不利于这些企业与周边居民的和睦关系。天然橡胶环保改性剂ORA-100以其特殊的性能,能够很好地解决这些问题,起到稳定天然橡胶的门尼黏度,改善生产操作环境(降低天然橡胶的臭味)、实现节能环保的作用。通过对这个材料的性能研究,介绍了它的一些独特的功能、作用机理和应用。     

利用国产粘度杯和混合图确定粘度

介绍了用国产粘度杯和混合液粘度确定图测定油漆、油墨、胶液混合液粘度的原理和方法，从而控制其生产过程中的粘度。     

Measurement of the temperature dependent viscosity of biodiesel fuels

Micro heat exchangers may be used for winterisation of biodiesel at temperatures below 273 K. For a proper design of our micro heat exchangers the viscosity of biodiesel must be known around a temperature of 273 K. Therefore, different samples of biodiesel were examined in the range of 258-303 K and empirical equations for the temperature dependent viscosities computed. Above temperatures of 273 K an exponential equation based on the usual Arrhenius form describes all measurements well. Below 273 K the viscosity sharply rises within 2 K and then further increases. The reason is the precipitation of crystalline saturated methyl esters.     

Comparisons of Biodiesel Produced from Unrefined Oils of Different Peanut Cultivars

Biodiesels were prepared according to standard procedures from unrefined oils of eight commercially available peanut cultivars and compared for differences in physical properties important to fuel performance. Dynamic viscosity, kinematic viscosity and density were measured from 100 to 15 °C, and differences (p < 0.05) in these physical properties occurred more frequently at lower temperatures when comparing the different cultivars. Unlike data for the oil feedstocks, no meaningful correlations among biodiesel fatty acid profiles and either fuel viscosity or density were observed. Low temperature crystallization of the peanut biodiesels was measured via differential scanning calorimetry. Increased concentrations of long chain saturated fatty acid methyl esters (FAME) were associated with an increased propensity for low temperature crystallization, and the single FAME category most associated with low temperature crystallization was C:24. Tempering at 10 °C followed by analysis of the soluble fractions (winterization), improved crystallization properties and confirmed the importance that long chain saturated FAMEs play in the final functionality of peanut biodiesel. Peanut data is also compared to data for canola and soy biodiesels, as these feedstocks are more common worldwide for biodiesel production. Overall, this work suggests that minimizing the concentration of long chain saturated FAMEs within peanut biodiesel, either through processing and/or breeding efforts would improve the low temperature performance of peanut biodiesel.