实施电石法PVC生产过程中的循环经济

介绍了电石法聚氯乙烯生产过程中水、尾气和电石渣的循环利用及超低含量氯化汞触媒的使用情况。提出了要以“减量化、再利用、资源化”为原则,实现低消耗、低排放、高效率的循环经济。     

PVC-U型材弹性模量测试偏差分析

在对PVC-U型材弹性模量试验中发现，同一样品的规则样条与不规则样条的弯曲弹性模量相差较大。不规则样条的负荷-挠度曲线上会出现拐点，如果不对曲线进行处理直接计算得到的弯曲弹性模量偏小。在不规则样条的负荷-挠度取拐点后直线段切线与横坐标的交点作零点修正后所测得的弯曲弹性模量比较接近真实值。通过实验可以验证处理后的方法测得的弹性模量与均匀规则样条的弯曲弹性模量相近。     

Modelling of copper etching in aerated chloride solutions

The effect of dissolved oxygen on the rate of chemical etching of copper by acidic cuprous chloride solution was investigated numerically for the case of a rotating disc electrode (RDE). Copper dissolution in aerated acidic cupric chloride solutions of composition 3.5M CuCl2 + 0.5M HCl + 0.5M KCl and 3.5M CuCl2+0.5M HCl was investigated with consideration of the instantaneous homogeneous reaction 4CuCl32-+4H++O2rlhar4CuCl 3-+2H2O which takes place within the mass transport boundary layer. It was assumed that CuCl32- and O2 react instantaneously, resulting in the formation of a reaction plane which separated the mass transport boundary layer into two regions: a region adjacent to the electrode where oxygen was depleted, and a region adjacent to the bulk where CuCl32- was absent. A one-dimensional mathematical model was developed to predict the position of the reaction plane. The model accounted for diffusion, migration and fluid flow generated by an RDE and included nine species and five heterogeneous electrochemical reactions. The homogeneous redox reaction served to regenerate the chemical etchant solution and thus enhance the etch rate. With increasing oxygen concentration and rotation rate the reaction plane was found to move closer toward the electrode and thus the etch rate of copper increased. Addition of KCl increased the Cl- content in solution so as to shift the reaction plane toward the bulk.     

PE-LLD／EVA／Mg（OH）2／复合阻燃剂高效无卤阻燃体系的研究

采用线形低密度聚乙烯/乙烯-醋酸乙烯共聚物作为复合材料主体,表面处理过的氢氧化镁(Mg(OH)2)为主阻燃剂,以微胶囊化红磷和自制硅类阻燃剂为核心的复合阻燃剂为阻燃增效剂,重点探讨了Mg(OH)2和复合阻燃剂的阻燃效果。结果表明,Mg(OH)2与复合阻燃剂并用具有良好的协同效应,当Mg(OH)2用量40份,复合阻燃剂5～7份时,可获得较高的氧指数,垂直燃烧试验通过FV0级,且材料抗静电能力提高,力学性能、加工性能较好。     

Galvanostatic and microscopic studies of nodulation during copper electrolysis

The galvanostatic technique on a laboratory scale has been shown to be a useful tool in detecting the presence of nodules on the cathode during copper electrodeposition by using the value of the starting electrolytic potential and by the presence of a cathodic polarization peak on the potential–time curve. Studying the morphology of the deposit with a scanning electron microscope at various magnifications confirmed the galvanostatic results. It is postulated that inappropriate concentrations and/or ratios of the additives (thiourea, gelatin and chloride ions) are associated with a certain current density that generates intergranular microcracks due to adsorption of the additives and leads to the formation of nodules at the macroscale.     

金属皂类热稳定剂对RPVC流变性能的影响

采用Brabender转矩流变仪，分析并探讨了硬酯酸钡（BaSt2）、硬酯酸铅（PbSt2）、硬酯酸钙（CaSt2）、硬酯酸锌（ZnSt2）4种硬酯酸金属皂类热稳定剂以及复配BaSt2／PbSt2热稳定剂对硬质聚氯乙烯（RPVC）流变性能的影响。结果表明，BaSt2，CaSt2能够促进RPVC的塑化，而PbSt2和ZnSt2却推迟RPVC的塑化；在复配BaSt2／PbSt2稳定剂体系中，随着BaSt2比例的增大，塑化时间缩短，但BaSt2与PbSt2按分子数1：1比率时，RPVC熔体粘度增幅较大。     

镁铝水滑石及其复合体系对PVC热稳定性能的调控

采用比色法、热失重法等研究了不同镁铝摩尔比的水滑石(LDHs)对PVC糊热稳定性能的影响。结果表明,在镁铝比分别为2、3、4的样品中,镁铝比为2的LDHs对PVC的热稳定效果最佳;将其与传统的铅盐、有机锡稳定剂复配,均具有良好的协同效应,可以实现对PVC糊热稳定性能的控制。其中,PVC/Mg-AlLDHs/Sn以100∶1.5∶1.5(质量份数,下同)比例复合后的体系,不仅热稳定性能优于传统的的铅盐体系,而且具有较低的糊黏度及较好加工流变性能。     

一种单面涂铝PVC塑料吊顶材料燃烧性能的实验研究

采用锥形量热仪对市场上常见的一种内装修单面涂铝PVC吊顶材料的燃烧性能进行了实验研究。实验结果表明，在不同的辐射功率和不同暴露面下，该材料表现出不同的燃烧性能。当涂铝面(正面)暴露燃烧时，其质量损失速率(即燃烧速率)比未涂铝面(背面)小，正面的引燃时间比背面引燃时间长，这些特性对减小燃烧时的火焰蔓延速度有利；而正面暴露燃烧时的发烟量和一氧化碳的产率则比背面暴露燃烧时大，这一特性将增大材料燃烧时的烟气危害性。     

绿色水处理剂氢氧化镁应用的研究进展

氢氧化镁(氧化镁)被称为绿色安全的废水处理剂,本文评述了氢氧化镁在环境保护方面的研究与应用进展,包括工业废水中铅、铬、镍等重金属离子的去除和酸性废水的中和处理,并列举了氢氧化镁对一些实际废水的良好处理效果,包括其对一些特殊废水如含硼废水和放射性废水的处理效果,最后展望了其在生产和应用方面的发展前景。     

硼酸与硫酸镁对硼收率影响的分析

介绍了在硼酸生产工艺中影响硼收率的主要因素。以生产系统中硼酸浓度和硫酸镁两个方面探讨了对硼收率影响的原因，并把分析结果应用于生产实践中，调整了部分工艺参数。证明：调整酸化浓度，控制母液中硼酸含量，硼的收率比以往确有提高，是一种不增加设备，不增加投资的行之有效的方法。