大分子表面活性剂PP-g-PEG对聚丙烯薄膜的表面改性

将聚乙二醇接枝聚丙烯(PP-g-PEG)作为大分子表面活性剂用于PP薄膜的表面改性。使用衰减全反射红外光谱、接触角测定仪、电子材料试验机等方法,考察了预处理条件、PEG链段长度及含量对改性薄膜的表面润湿性、表面自由能、表面电阻率等性能的影响。研究表明,随预处理温度的提高,PEG链段向薄膜表面迁移速率加快,聚集程度提高,导致薄膜表面极性和表面自由能迅速增大。经过100℃、6 h的预处理,PEG链段薄膜表面聚集形成的微区基本覆盖薄膜表面。随着薄膜中PEG链段含量增加,薄膜表面聚集的PEG链段增多,表面改性效果增强。当PEG链段含量增加到2%后,薄膜表面PEG相对含量及表面改性效果趋于稳定。PEG链段长度影响其在薄膜中的迁移扩散能力以及在薄膜表面的聚集状态,在相同预处理条件和PEG含量下,薄膜表面PEG聚集程度的高低顺序为:PP/PP-g-PEG-6000薄膜PP/PP-g-PEG-2000薄膜PP/PP-g-PEG-1000薄膜。但是由于在PP/PP-g-PEG-6000薄膜表面形成的PEG微区分布密度低于PP/PP-g-PEG-2000薄膜,因而PEG链段长度为6 000的PP-g-PEG-6000对薄膜的表面改性效果不如PEG链段长度为2 000的PP-g-PEG-2000。     

增塑剂对聚乳酸/热塑性淀粉共混物结构与性能的影响

采用柠檬酸三丁酯(TBC)、聚乙二醇(PEG)增塑聚乳酸(PLA)/热塑性淀粉(TPS)共混体系,调节PLA的流变性能,改善PLA与TPS相容性、熔融共混特性和共混物的微观结构和力学性能.结果表明:TBC的改性效果比PEG更佳;TBC能增加TPS分散均匀性,相分散尺寸明显变小;TBC改性PLA/TPS的拉伸强度和断裂伸长率明显提高.吸水率较小.     

天然气乙二醇脱水系统监测分析与防腐蚀方案

针对天然气浅冷分离过程中乙二醇脱水装置生产运行存在的腐蚀问题，对乙二醇工艺介质、系统沉淀物以及贫、富乙二醇换热器进行了监测与分析。分析结果发现：随着装置运行时间的延长，乙二醇循环液体的酸度和Fe^3＋含量增加，pH值降低；系统产生的黑色沉淀物主要由硫化铁和氧化铁构成；贫、富乙二醇换热器传热效率下降，总传热系数值很低。为此，提出了几种解决方案。     

Ethylene glycols technology

Ethylene glycol (EG) or monoethylene glycol (MEG), the adduct of ethylene oxide (EO) and water, is the simplest glycol. It is the first of a homologous series of three dihydroxy alcohols discussed in this article. Diethylene and triethylene glycols (DEG, TEG) are the other two. These glycols are composed solely of carbon, hydrogen and oxygen. Although they have similar chemical properties, their applications vary mainly with physical properties such as viscosity, hygroscopicity and boiling point. The commercial route to ethylene glycols in use today involves the noncatalyzed thermal hydrolysis of ethylene oxide in water. This process produces chiefly mono-, di- and triethylene glycols and a small amount of tetraethylene and heavier glycols. The yield of monoethylene glycol via hydrolysis is controlled by the water-to-ethylene oxide ratio in the feed to the reactor system. Removal of excess water following the glycols-forming hydrolysis is energy intensive and requires capital investment in evaporators. Such costs limit the amount of excess water which is used. In practice, reactor feed water content is such that the selectivity to monoethylene glycol achieved ranges from 89-91%. The equipment elements in a simplified process flow diagram are discussed along with recommended materials of construction. Among other items discussed are a) a brief review of economic factors; b) health, safety and environmental issues; and c) commercial applications of the three glycols, MEG, DEG and TEG. Finally, recommendations for shipping, handling and storage are discussed.     

新戊二醇改性PET的合成研究

以对苯二甲酸（PTA）、乙二醇（EG）为主要原料,添加第三单体新戊二醇（NPG）合成了一系列不同NPG含量的共聚酯（PENT）,研究了NPG对酯化、缩聚过程的影响,分析了PENT共聚酯的常规性能。结果表明,酯化反应速率和聚合反应速率随NPG含量的增加而下降,共聚酯中的二甘醇（DEG）含量和端羧基（CEG）含量随NPG含...     

乙二醛的工业生产

阐述了以乙醛和乙二醇为原料,工业生产乙二醛的2种工艺的流程、装置;分析了2种工艺的特点;回顾了乙二醇工业生产的历史,介绍了现状。     

在聚乙二醇辛基苯基醚存在下,锌与5—Br—DMPAP显色反应的研究

研究了显色剂５－Ｂｒ－ＤＭＰＡＰ作为不度法测定Ｚｎ的新方法。在ｐＨ＝９．０缓冲溶液及非离子表活生剂聚乙二醇辛基苯基醚存在下,该试剂与Ｚｎ反庆生成稳定的紫红色配合物,其最大吸收波长为５５６ｎｍ,表观摩尔吸光系数为７．７２×１０＾４Ｌ．ｍｏｌ＾－１．ｃｍ＾－１,锌含量为０－１．２３×１０＾－５ｍｏｌ．Ｌ＾－１范围内服从比耳定律,该方法应用于人发,药品中锌的测定,结果令人满意。     

Oxidation of Propylene Glycol Methyl Ether Acetate Using Ozone-Based Advanced Oxidation Processes

The present study investigates the degradation of PGMEA and its TOC removal using O₃, UV/O₃, O₃/H₂O₂, and UV/H₂O₂ processes under various experimental conditions. Ozonation of PGMEA was substantially enhanced in the presence of UV light and H₂O₂. Approximately 33% of TOC enhancement was noted in UV/O₃ process over ozonation process. A linear relationship between PGMEA and H₂O₂ decomposition was observed in O₃/H₂O₂ and UV/H₂O₂ processes. The influence of solution pH on the decomposition of PGMEA was investigated and found that basic medium was the most efficient in all AOPs. After 60 minutes 62.4%, 100%, 90% and 54% of PGMEA decomposition at pH 10.0 was observed in O₃, UV/O₃, O₃/H₂O₂, and UV/H₂O₂ processes, respectively. It is concluded that UV/O₃ process is a promising approach for the oxidation and removal of PGMEA.