热塑性磷酸酯淀粉的制备与性能研究

以磷酸酯淀粉为基体、甘油和水为增塑剂,使用转矩流变仪制备了磷酸酯热塑性淀粉(TPS)。研究了甘油用量对于材料的塑化性能、流变性能、结晶行为以及力学性能的影响。结果表明:随着甘油含量的增加,热塑性磷酸酯淀粉的平衡扭矩减小,熔体质量流动速率增大,流动性提高,拉伸强度与断裂伸长率先增大后减小,而且结晶度下降,塑化程度提高;当淀粉/甘油/水的质量比为60/30/8时,材料具有较好的力学性能。     

宽温域下氟醚橡胶的加速老化行为和机理研究

基于氟醚橡胶使用环境的特殊性,从物理和化学角度,在宽温域（-40～225℃）条件下对某国产氟醚橡胶在4050航空润滑油中老化后的质量、力学性能、化学结构、元素组成及热稳定性等有关参数进行了研究,分析了老化温度和老化时间对氟醚橡胶性能的影响规律。结果表明：在相对较宽温域-25～200℃内氟醚橡胶的耐介质老化性能优异,其物化性能在长期老化过程中保持稳定;当老化温度达200℃以上时,溶胀和氧化反应增强,随着老化时间的增加,材料逐渐由软而韧变为硬而脆;特别是在高温225℃下,脱氟化氢反应导致大量C—F键断裂,F元素含量显著减少,同时氧化反应增强并生成CO键,导致O元素含量增多;低温老化过程中氟醚橡胶的质量、化学结构及元素含量基本不变,但-40℃时的玻璃化转变行为会导致力学性能的下降。     

改性聚酯的湿热老化性能研究

通过力学性能测试、差示扫描量热分析(DSC)和热失重分析等测试手段研究了聚酯(PET)改性料的湿热老化性能,结果表明:复合助剂的加入能显著提升体系的力学性能保持率,进而提升其湿热老化性能,提升的幅度随复合助剂中抗水解助剂含量的增加而显著增加;DSC分析表明复合助剂的引入起到促结晶的作用。PET改性料的湿热老化与结晶度的关系研究结果表明:湿热老化能提高PET改性料体系的结晶度,从而使得其力学韧性丧失,导致材料宏观的脆韧转变。     

四溴双酚A双(2,3-二溴丙基)醚阻燃V-2聚丙烯材料光稳定化研究

采用氙灯老化仪对四溴双酚A双(2,3-二溴丙基)醚阻燃V-2聚丙烯材料进行光老化,通过测色仪测试样品色差变化,评估材料的紫外老化性能。系统研究了不同钛白粉、抗氧剂、光稳定剂对材料紫外老化性能的影响。优选最佳配方与国外同类材料进行耐候性能及力学性能变化对比。     

蓖麻油聚氨酯防水涂料的制备与性能研究

采用可再生的蓖麻油先分别与三羟甲基丙烷(TMP)、甘油反应,再与TDI反应,生成端基为-NCO的蓖麻油基聚氨酯预聚体.对其-NCO含量进行测试,并采用FT-IR对材料进行定性分析.并对固化后的涂膜附着力、力学性能、耐磨性和耐水性能进行了测试.结果表明:采用甘油醇解蓖麻油合成的聚氨酯性能较好,其最佳反应时间为3～4 h,反应后-NCO含量为4.90%～5.32%,体系在-10～40℃能固化成膜,且成膜物有较好的防水性能和力学性能.     

应力-热氧作用下三元乙丙橡胶的老化行为

通过ATR-FTIR、超景深显微镜及力学性能、硬度、交联度测试分析,实时追踪了在应力-热氧老化场中三元乙丙橡胶(EPDM)的失效规律和微观结构演变过程。结果表明:EPDM的力学性能随老化时间增加而下降,试样表面逐渐变得粗糙,并出现明显裂纹,失去弹性;老化温度越高,性能劣化越快。在应力-热氧作用下,EPDM分子链被逐渐破坏,发生了降解、交联及氧化等反应,导致材料性能逐渐劣化。老化温度越高,分子链破坏程度越大,性能下降越显著。     

添加型光降解聚乙烯塑料性能研究

运用实验室氙弧灯光源暴露试验法对添加型光降解聚乙烯(PE)塑料袋进行老化试验,考察了不同光降解母料含量的PE塑料袋的拉伸性能和热氧稳定性。力学性能测试结果表明,随着光降解母料添加量的增加,样品的拉伸强度和断裂伸长率降低。其中当光降解母料添加量为60%时,样品老化后的断裂伸长率保留率横向达到2.04%,纵向达到5.45%,此时样品同时具有良好的使用性能和降解性能。热氧化性能测试结果表明,随着光降解母料添加量增加,样品老化后热氧化反应初始失重温度降低,老化前后的热氧化稳定性差别增大。     

EVA/Mg(OH)_2高填充复合体系热老化性能研究

将乙烯-乙酸乙烯共聚物(EVA)/Mg(OH)_2高填充复合材料进行常规热老化,用扫描电镜观察试样老化前后的断面形貌,并对老化后试样的介电性能和力学性能进行测试。结果表明:表面处理剂、增容剂强化了EVA与填料之间的作用,阻燃增效剂具有软化界面、抑制热胀冷缩中界面裂纹形成的作用,三者合理配合,能调控界面,有效抑制复合体系在热老化过程中的界面劣化,提高其耐热老化性能;力学性能测试结果能够全面概括材料整体性能的变化趋势,但对于某个单一成分引起的变化需用其他方法进行研究。     

聚乳酸/热塑性淀粉3D打印材料性能研究

采用甘油、水为增塑剂,马来酸酐为反应增容剂,使用同向平行双螺杆挤出机制备得到热塑性淀粉（TPS）,然后采用熔融共混制备得到PLA/TPS 3D打印材料,通过红外光谱、热重分析、差示扫描量热分析和力学性能测试对材料的热性能和力学性能进行了研究。实验结果发现,TPS提高了PLA的热稳定性且起到一定增塑、增韧作用,有利于3D打印成型。     

交联POE紫外老化行为研究

本文研究了不同交联剂含量下交联POE胶膜的紫外老化性能。结果显示,随着DCP含量的增加,残留的DCP逐渐增加,会加速交联POE的老化。在老化过程中会出现再交联现象,会导致透过率回升,当DCP含量为0.6phr时,透过率回升了34%,但对力学性能的影响较小,拉升强度下降了70%,撕裂强度下降了33%,没有因再交联过程而回升,老化后胶膜的表面出现裂纹,变得粗糙。在老化过程中发生了断链,生成了大量的酮基、酯基、羟基,这些基团导致了胶膜各性能的下降。     

底座连接口特征参数对显示器后壳注塑质量的影响分析

在Moldflow分析软件的基础上,对显示器后壳进行仿真研究,以翘曲变形量为质量指标,结合控制变量法进行单因素变动实验,保持注射工艺参数不变,研究显示器后壳底座连接口对制品翘曲变形的影响.对数据进行图表分析,结果表明显示器后壳尺寸定位68.58 cm(27英寸)时,底座连接口选用圆形,连接口位置距离底边26 mm,尺寸...     

The role of the symmetry and the flexibility of the anion on the characteristics of the nanostructures and the viscosities of ionic liquids☆

The transport properties of ionic liquids (ILs) are crucial properties in view of their applications in electrochem-ical devices. One of the most important advantages of ILs is that their chemical–physical properties and conse-quently their bulk performances can be well tuned by optimizing the chemical structures of their ions. This will require elucidating the structural features of the ions that fundamentally determine the characteristics of the nanostructures and the viscosities of ILs. Here we showed for the first time that the“rigidity”, the order, and the compactness of the three-dimensional ionic networks generated by the anions and the cation head groups determine the formation and the sizes of the nanostructures in the apolar domains of ILs. We also found that the properties of ionic networks are governed by the conformational flexibility and the symmetry of the anion and/or the cation head group. The thermal stability of the nanostructures of ILs was shown to be con-trolled by the sensitivity of the conformational equilibrium of the anion to the change of temperature. We showed that the viscosity of ILs is strongly related to the symmetry and the flexibility of the constitute ions rather than to the size of the nanostructures of ILs. Therefore, the characteristics of the nanostructures and the viscosities of ILs, especially the thermal stability of the nanostructures, can be fine-tuned by tailoring the symmetry and the conformational flexibility of the anion.     

浅谈设备的性能与操作对胎面压出质量的影响

简要介绍了胎面压出的工作原理及工艺过程，对设备的配置及操作对胎面压出质量的影响进行了分析，并对压出过程中常见的质量缺陷、造成的原因以及解决措施提出了自己的见解。     

Investigation of the effects of fatty acids on the compressive strength of the concrete and the grindability of the cement

In cement industry, a great energy consumption has been observed during grinding of clinker. To reduce this consumption, some waste products have been used as grinding aids.In this investigation, the effects of sunflower oil (SO), oleic acid (OA), stearic acid (SA), myristic acid (MA) and lauric acid (LA) on the fineness and strength of the cement have been examined. These aids were added into clinker in certain ratios based on the cement clinker weight and the grinding has been done for a definite time at the same condition.All of the fatty acids used increased the fineness as compared with the cement without the grinding additives. SO and OA decreased the strength significantly, LA decreased it to a lesser extent and SA increased it definitely according to the common cement. But MA did not alter the strength of the cement as much as SA. In addition, the covering of the balls influences the grinding of cement clinker unfavourably.     

煤粉流动性对GSP气化炉气力输送的影响研究

针对GSP气化装置煤粉气力输送在试车阶段出现的煤粉锁斗下料不畅、发料罐输送性能不佳等问题,从原料煤性质和工业装置的改进方面出发,通过煤粉的流动性参数的测量与研究,分析出现上述工程问题可能的内在原因,并提出工业装置改进方法,为保证GSP煤粉气力输送工业装置的正常运行提供解决办法。     

关于建立火炸药安全数据库的探讨

由反映火炸药及其制品的危险性能和用于对它们的生产、储运系统进行安全评价数学模型出发,探讨了如何建立一个全面、实用的火炸药安全评估数据库。通过对此数据库内容、数据表示方法、数据搜索方法以及建立步骤的讨论,明确了该数据库的使用对象和主要功能。     

The effect of the length of the oxyethylene chain on the conductivity of the polyurethaneurea electrolyte

Polyurethaneureas (PUU), which were synthesized from 4,4′-diphenylmethane diisocyanate (MDI), poly(ethylene glycol) (PEG), and 3,5-diaminobanzoic acid (DABA), were used as polyelectrolytes in this study. Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR) were used to monitor the effect of the various kinds of PEG on the changes in morphology of PUU electrolytes corresponding to the concentration of lithium perchlorate (LiClO₄) dopants. The results of DSC and FT-IR indicate the Li⁺ ions coordinate with the soft and hard segments. Additionally, the crystallinity of the PEG soft segment and the ordered hydrogen-bonded urea carbonyl groups decreased with increasing salt concentration. Impedance spectroscopy (IS) measurements show that the PUU electrolyte with the high phase separation degree has the high ionic conductivity. The hard-segment T_g and the soft-segment T_m influence the conductivity behavior of polyelectrolytes with increasing measurement temperature.     

Effect of the drafting force on the strength of the bottom of the spinneret

In spinning basalt fibres, the drafting force is in the same range as in spinning of glass fibres. The effect of the drafting force can not be considered in the calculation for the strength and rigidity of the bottom of the spinneret. __________ Translated from Khimicheskie Volokna, No. 5, pp. 47–50, September–October, 2007.