茂金属聚乙烯弹性体和三元乙丙橡胶增韧聚丙烯的比较

用茂金属聚乙烯弹性体（mPE）代替三元乙丙橡胶（EPDM）对聚丙烯（PP）增韧改性并进行了比较。结果表明,mPE共聚物中的辛烯质量分数越高,其中对PP的增韧效果越好;随着共混物中弹性体质量分数的增加,共混物的拉伸强度和弹性模量降低,扯断伸长率增大。PP/mPE与PP/EPDM增韧体系相比,二者的拉伸强度差别不大,但PP/mPE的弹性模量和扯断伸长率稍低;与EPDM相比,mPE对PP具有较好的增韧效果,含有质量分数40% mPE的共混物试样在-30℃下的缺口冲击强度已超过纯PP的20倍,约是相同弹性体质量分数PP/EPDM的近9倍。另外,PP/mPE还具有较低的拉伸永久变形、压缩永久变形和蠕变变形。     

mPE弹性体/PP共混物的流变行为与力学性能

用茂金属聚乙烯弹性体（mPE)代替传统的弹性体,对聚丙烯（PP）进行增韧改性,绘制了不同配比mPE/PP共混物熔体的流变曲线,讨论了共混物的组成,切应力和剪切速率以及温度对熔体流变行为,熔体粘度的影响。测定了共混物熔全的非牛顿指数,熔体质量流动速率及力学性能,为mPE共混改性PP提供了理论依据。结果表明,mPE适用于PP的增韧改性,增韧效果取决于共混物中mPE的用量,当mPE质量分数达到25%-40%时,共混材料既有较高的拉伸强度和韧性,又有较好的加工性能,mPE/PP共混物熔体的假塑性流动随mPE用量的增加向更高切应力或更高剪切速率方向移动。     

动态硫化法制备EPDM/PP/WRP的初步研究

初步研究了EPDM／PP／WRP共混材料的力学性能和微观结构。结果表明，废胶粉用动态硫化法可以改善EPDM／PP／WRP共混物的机械性能。通过胶料扯断断面的扫描电镜照片的分析，可证明改性后的废胶粉与聚丙烯的界面粘着力增强。     

动态硫化增韧聚丙烯／三元乙丙橡胶共混物的研究

研究了动态硫化和简单共混增韧聚丙烯（PP）／三元乙丙橡胶（EPDM）共混物的力学性能、形态结构、流动性能和脆韧转变。结果表明：动态硫化的增韧效率要比简单共混的增韧效率高；随着EPDM用量的增加，共混物的力学性能均随之发生变化，流动性明显降低；简单共混物的橡胶颗粒尺寸随EPDM含量的增加呈增大趋势，而动态硫化可以降低橡胶颗粒的尺寸；动态硫化物的临界基体层厚度大约为0.3μm，简单共混物的临界基体层厚度大约为0．2μm，并且动态硫化和简单共混物均在各自的临界基体层厚度处发生脆韧转变，验证了wu氏增韧理论。     

玻纤增强茂金属聚乙烯弹性体改性聚丙烯的研究

采用短玻纤（SGF）对PP／茂金属聚乙烯弹性体（mPE）共混物进行增强,制得PP／mPE/SGF三元共混复合材料,分别对PP／mPE二元共混物和PP／mPE/SGF三元共混复合材料的力学性能进行了研究。探讨了弹性体用量、SGF的用量和表面处理对共混物和复合材料拉伸性能、低温冲击韧性和蠕变性能的影响。结果表明,PP／mPE/SGF三元共混复合材料同时具有良好的刚性和韧性。     

TBC对EPDM/PP阻燃化的影响

用氧指数(LOI)测定、力学性能测定、热失重分析(TGA)方法研究了TBC对三元乙丙橡胶(EPDM)／聚丙烯(PP)阻燃耐热性和力学性能的影响。结果表明，使用TBC，EPDM／PP的阻燃效果较好，TBC主要发挥气相阻燃作用。5％TBC的加入增加了共混体系的拉仲强度和断裂伸长率；但随着TBC用量的继续增加，拉伸强度和断裂伸长率都有所降低。加入TBC后，共混物的起始失重温度明显降低，但对EPDM／PP的热稳定性没有多大的影响，不影响EPDM／PP的正常使用。     

动态硫化EPDM/PP共混型热塑性弹性体的耐屈挠疲劳性能的研究

对动态硫化EPDM/PP共混型热塑性弹性体耐屈挠疲劳性能的研究表明:选择合适的橡塑共混比、硫化剂用量、补强剂品种及用量、软化剂品种,使EPDM/PP共混物不仅可以获得良好的物理机械性能,而且还可明显提高耐屈挠疲劳性能.     

1999年中国高分子材料老化与应用文摘

EPDM/PP共混物老化性能的研究/赵永仙(青岛化工学院)/塑料工业.1999,27(4),30～31转38.研究了三元乙丙橡胶(EPDM)改性聚丙烯(PP)共混物的性能,探讨了不同含量的EPDM对共混物力学性能、热性能、流变性能的影响,还探讨了不同品种、不同含量的抗氧剂对共混物耐老化性能的影响.经EPDM改性的PP拉伸强度降低、冲击强度和断裂伸长率提高耐热,性、熔点随EPDM含量增加而降低,熔体粘度增大,假塑性增强,添加抗氧剂大大提高了共混物的耐老化能力、主辅抗氧剂并用效果更好.获得了能在高温下长期工作的改性PP共混物.     

三元乙丙橡胶共混改性聚丙烯

分别用茂金属催化聚合所得的三元乙丙橡胶(mEPDM)和传统Ziegler-Natta催化剂聚合所得的三元乙丙橡胶(EPDM)对PP进行共混改性。考察了增韧剂质量分数对共混物冲击强度、拉伸强度和热变形温度等力学性能的影响,以及共混物结构形态和结晶行为。结果表明,与PP／EPDM共混物相比,PP／mEPDM共混物的脆韧转变增韧剂临界质量分数小,扯断伸长率高。PP／mEPDM共混物的脆韧转变区间远小于PP／EPDM共混物。随增韧剂质量分数的增加,PP／mEPDM和PP／EPDM共混物的拉伸强度、弹性模量和维卡软化点均单调下降,但后者的下降幅度更大。电镜分析和结晶行为研究表明,PP与mEPDM的相容性优于PP与EPDM的。     

MOS阻燃动态硫化PP/EPDM性能研究

结合碱式硫酸镁晶须（MOS）的补强和阻燃功能，以微胶囊红磷（MRP）为协效剂，制备了无卤阻燃型PP（聚丙烯）／EPDM（三元乙丙橡胶）／MOS／MRP共混物，并与PP／EPDM／Mg（OH）2／MRP共混物进行比较。氧指数（LOI）及垂直燃烧（UL-94）测试表明MOS的阻燃效果优于Mg（OH）2。力学性能测试表明，MOS对PP／EPDM热塑性雌性体具有一定的增强作用，PP／EPDM／MOS／MRP阻燃体系的力学性能明显优于PP／EPDM／／MRP阻燃体系。而PP／EPDM热塑性弹性体的动态硫化进一步提高了PP／EPDM／MOS／MRP阻燃体系的力学与阻燃性能。     

乙烯酮(双乙烯酮)下游产品废水的治理技术

乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。     

几种乙炔加压设备性能的比较

阐述并比较了几种加压设备在乙炔加压清净过程中的性能和特点。     

三种煤样燃烧热的测定

本文通过三个厂家提供的三种煤样燃烧热的测定,由测定结果综合得出3号煤样燃烧最完全、燃烧热也最大,是三个煤样中最好的一种。     

Semi-empirical equation of state of metals. Equation of state of aluminum

A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO₂) of density 0.08 g/cm³. __________ Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008.     

水泥水化热测定方法综述

水泥水化热是中、低热水泥和核电工程用水泥的一项关键的技术指标。全球范围内测定水泥水化热的方法有溶解法、直接法/半绝热法、等温传导量热法三种。本文总结了中、美、欧相关方法标准,对其测试原理、仪器设备、试验过程等方面进行了比对,并对其在领域的应用做了简单的概括。     

Calorimetric and Computational Study of Enthalpy of Formation of Diperoxide of Cyclohexanone

A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out.     

我国聚碳酸酯工业发展概况

介绍我国聚碳酸酯生产能力和消费需求,对聚碳酸酯在信息工业中的应用作了简短介绍     

小议汽车涂装工艺设计对涂装成本的影响

论述了涂装工艺设计对涂装设备投资、涂装生产成本的影响。     

Effect of degree of deacetylation of chitosan on the kinetics of ultrasonic degradation of chitosan

The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003     

Measurement of the gradient of viscosity with composition of mixtures of non-ideal gases

A perturbation viscometer is a differential capillary viscometer that measures the logarithmic viscosity gradient of the viscosity-composition curve for gas mixtures. Measurements are made at different gas mixture compositions. Integration of the logarithmic viscosity gradients measured over the full composition range gives the mixture viscosity relative to the viscosity of one of the pure components of the gas mixture. This method is attractive because, for measurements of equal precision, integration of the gradients is potentially an order of magnitude more precise than measurement of the viscosities directly. It can also work at high and low temperatures and perhaps high pressures.The perturbation viscometer has been used to make measurements on ideal gas mixtures at ambient and elevated temperatures. The situation is more complicated when the gas mixtures are non-ideal. Extra effects due to density differences, molar volume change on mixing and differential thermal expansion may be measured in addition to the desired viscosity change producing systematic errors in the results. Thus, a more sophisticated apparatus is required. The standard perturbation viscometer has been modified to separate out the extra effects to permit measurement of the true change in viscosity. In addition, the theoretical operation of the modified apparatus has been revised to account for the design changes to permit calculation of the viscosity-composition profiles from the results.The apparatus has been tested using helium-HFC-125 mixtures and two new viscosity-composition profiles are presented for these mixtures at 23 and . Internal consistency tests have been used to confirm that the data produced are of high quality with an estimated uncertainty in the viscosity ratio data at of 0.9% and at of 1.5%.