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微孔发泡聚碳酸酯片材的制备与性能研究 总被引:3,自引:0,他引:3
在聚碳酸酯(PC)的玻璃化温度(tg)和熔融温度(tm)之间,采用模压法制备出用挤出、注射和常规发泡难以加工成型的薄型微孔发泡PC片材。模压法有制备周期短、工艺简单、操作容易、价格低廉等优点。通过热性能及力学性能测试.表明用模压法制备的微孔发泡PC片材性能优异。 相似文献
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分析了高密度聚乙烯(HDPE)管材专用树脂DGDB 2480H及典型双峰PE 100级管材专用树脂的性能。两者的力学性能相当;DGDB 2480H具有较低的剪切黏度,有利于管材的加工成型,熔体强度为1.05 MPa,与国产及进口管材专用树脂相当,比普通HDPE大,有利于大口径管材的挤出。 相似文献
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介绍了聚全氟乙丙烯(FEP)树脂的加工特性、主要方法和注意事项;叙述了FEP的挤出成型制作管材、电线包覆层、薄膜、片材、单丝和泡沫的原理、方法、工艺和设备. 相似文献
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在对管材专用料高密度聚乙烯(HDPE)4803T的性能测试和结构表征的基础上,研究了管材加工温度和挤出速度对加工参数的影响情况,并对管材的性能进行了测试.结果表明,HDPE4803T属典型的双峰分布聚乙烯树脂,其性能满足PE80级管材料的指标要求.材料的熔体强度对加工温度变化的敏感性较弱.挤出温度和挤出速度对管材的性能影响很小,采用该管材专用料,可以在较宽的挤出温度和挤出速度范围内制备出性能优良的管材. 相似文献
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表8 PCTFE的品级、特征和用途┌────┬─────────┬──────────┬───────────────────┐│制造公司│商品名及品级 │特征 │用途 │└────┼─────────┼──────────┼───────────────────┤ │l │ 粉末(10~60目) │模压成型,片材 │ │…木才二。、cT,E │ 粒状粉末 │模压、挤塑、注塑、传递模塑成型,片材、│ │一M一300 │ 粒料 │棒、管材 │ │ M一300H │粒状粉末(高分子量) │模压、挤塑、注塑、传递模塑成型,棒、 │ │ M一300P │粒料(… 相似文献
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复合拉伸力场挤出HDPE片材的力学性能 总被引:1,自引:1,他引:0
利用收敛-发散口模挤出制备了高密度聚乙烯(HDPE)片材,研究了挤出温度对片材力学性能的影响.结果表明:在复合拉伸力场作用下,熔态挤出(140℃)片材的纵、横向屈服拉伸强度分别为28.3,27.0MPa,固态挤出(112℃)片材的纵、横向屈服拉伸强度分别为181.4,51.3 MPa,纵、横向屈服拉伸强度分别增加了540%和90%.与固态挤出相比,熔态挤出片材纵、横向断裂伸长率分别增加了760%和124%.扫描电子显微镜显示,熔态挤出HDPE片材由球晶结构构成;固态挤出片材由大量垂直于挤出方向规整排列的片晶组成,并有少量的串晶生成,片晶厚度增加,这种结构有利于改善制品的双向力学性能. 相似文献
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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。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
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.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
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. 相似文献
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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%. 相似文献
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醋酸纤维素取代基分布与性质的关系 总被引:9,自引:0,他引:9
分析了以吡啶为溶剂的醋酸纤维素的13C-NMR核磁共振谱,得出了三种不同位置羟基的取代度。结合X—射线和DSC分析,初步说明具有相同取代度但未经水解和经过水解的醋酸纤维素(CA) 性质上的差异是由于三个羟基上的取代度分布不同及消晶程度差异所致。 相似文献