亚克力共聚PVC新型管材

新型供水管材-亚克力(Acrylic即丙烯酸树脂)共聚PVC管，所用材料是由超微粒子丙烯酸树脂弹性体与PVC接枝共聚而成，在保持原有PVC刚性性能基础上，提高了低温冲击性能及卫生性能，可用于供水管、抗震管及其他饮料、化工流体输送。     

ACR-g-VC共聚抗冲制品专用树脂研究进展

叙述了PVC树脂的增韧机理，归纳了PVC制品的增韧方式，对冲击改性剂ACR的合成过程及结构性能表征方法进行了详述，并研究了ACR—g—VC接枝共聚树脂的制备要点，简要介绍了接枝共聚树脂性能的评价手段。     

接枝共聚法增韧改性聚氯乙烯树脂

综述了悬浮溶胀接枝共聚法、悬浮溶解接枝共聚法和悬浮低压接枝共聚法三种接枝共聚方法增韧改性聚氯乙烯树脂(PVC)的制备工艺,以及接枝共聚增韧改性PVC的结构特征和性能。接枝共聚法与共混法相比,明显改善了增韧改性剂和PVC之间的相容性,显著提高了增韧改性剂对PVC的增韧效果,表明了采用接枝共聚方法已成为增韧改性PVC的一种更有效的途径。     

ACR—g—VC接枝共聚高抗冲树脂研究进展

本文叙述了PVC树脂的增韧机理，归纳了PVC制品的增韧方式，对抗冲改性剂ACR的合成过程及结构性能表征方法进行了详速，并研究了ACR—g—VC接枝共聚树脂的制造要点，最后简要介绍了接枝共聚树脂性能的评价手段。     

高抗冲ACR接枝VC共聚树脂的应用

比较了ACR接枝VC共聚树脂与CPE对PVC干混料加工性能、给水用PVC-U管材性能的影响。结果表明:①与CPE相比,ACR接枝VC共聚树脂可降低PVC干混料的平衡转矩,缩短塑化时间,节约能源消耗;②对于Φ32、Φ110给水用PVC-U管材,添加ACR接枝VC共聚树脂生产的PVC-U管材性能全部符合国家标准,且综合性能全部优于添加CPE生产的PVC-U管材。     

国外合成氯乙烯接枝共聚物技术

本文综述了国外氯乙烯接枝共聚物合成技术,包括以PVC为主链的接枝共聚和以PVC为侧支链的接枝共聚技术。同时介绍了一些商品氯乙烯接枝共聚物及其性能、用途,并简单介绍了一些提高共聚接枝率的方法。     

国外典型特种PVC树脂的性能、用途和制备方法(续1)

通过查阅大量国外的专利和论文,总结了以下4类特种PVC树脂的性能、用途和制备方法:①只以氯乙烯为原料,通过不同的成粒过程或不同的聚合条件制备的特种PVC树脂;②由多种单体共聚而成的PVC共聚树脂;③通过接枝改性制备的PVC接枝树脂;④对PVC树脂的侧基或端基进行化学改性制备的特种PVC树脂。     

国外典型特种PVC树脂的性能、用途和制备方法(续完)

通过查阅大量国外的专利和论文,总结了以下4类特种PVC树脂的性能、用途和制备方法:①只以氯乙烯为原料,通过不同的成粒过程或不同的聚合条件制备的特种PVC树脂;②由多种单体共聚而成的PVC共聚树脂;③通过接枝改性制备的PVC接枝树脂;④对PVC树脂的侧基或端基进行化学改性制备的特种PVC树脂。     

国外典型特种PVC树脂的性能、用途和制备方法(待续)

通过查阅大量国外的专利和论文,总结了以下4类特种PVC树脂的性能、用途和制备方法:①只以氯乙烯为原料,通过不同的成粒过程或不同的聚合条件制备的特种PVC树脂;②由多种单体共聚而成的PVC共聚树脂;③通过接枝改性制备的PVC接枝树脂;④对PVC树脂的侧基或端基进行化学改性制备的特种PVC树脂。     

悬浮ACR接枝共聚树脂与普通PVC共混树脂性能比较

在相同的实验检测条件下,对比分析了悬浮ACR接枝共聚树脂与PVC SG-5、PVC SG-5和抗冲改性剂CPE(或ACM)共混树脂基本物理力学性能、流变性能等的差异。比较结果表明,悬浮ACR接枝共聚树脂更具有优势。     

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.     

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.     

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。     

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.