阳离子聚合光引发剂及其阳离子反应机理

综述了阳离子聚合光引发剂的种类、制备和应用，介绍了它们的光分解和由此引发的光引发阳离子聚合反应机理。     

光引发阳离子聚合及其在环氧树脂固化研究中的进展

从光引发阳离子聚合的特点、常见阳离子型光敏引发剂及其引发聚合机理、光引发环氧树脂阳离子聚合体系及发展前景等几个方面进行了简要概述。     

二苯基碘Weng氟硼酸盐引发AGE阳离子光聚合与光交联的研究

用合成的二苯基碘Ｗｅｎｇ硼酸盐作为光敏引发剂,研究了含乙烯基和环氧基两种不同官能基的烯丙基缩水甘油醚（ＡＧＥ）的阳离子光聚合前后微观结构的变化,讨论了其阳离子光聚合的特征和机理,测定了光聚合经起光交联的凝胶转化率曲线。     

二苯基碘鎓氟硼酸盐引发AGE阳离子光聚合与光交联的研究

用合成的二苯基碘钅翁氟硼酸盐作为光敏引发剂 ,研究了含乙烯基和环氧基两种不同官能基的烯丙基缩水甘油醚 ( AGE)的阳离子光聚合和聚合前后微观结构的变化 ,讨论了其阳离子光聚合的特征和机理 ,测定了光聚合引起光交联的凝胶转化率曲线     

阳离子光引发剂研究进展

阳离子型光引发剂是一类新型的紫外光固化材料的引发剂。本文介绍了阳离子光引发剂的主要种类及各自的特点 ,讨论了其光引发机理 ,并简述了阳离子光引发剂的的发展概况和主要用途。     

光致阳离子聚合引发剂的进展

光致阳离子聚合体系具有聚合速度快、不受氧干扰以及对水不敏感等优点,为了适应光致阳离子聚合体系的发展,可进行光致阳离子聚合的单体和光致阳离子引发剂的研究越来越受到人们的重视,本文就其中的一方面光致阳离子引发剂的种类、制备以及引发机理进行了综述。     

光聚合现状与展望

本文叙述了自由基和阳离子聚合光引发剂体系的最新进展,并且提供了不同引发模式下在所有光引发体系中有关引发效率、波长限制和环境安全问题的解决办法。在过去10年里,通过光聚合制备了复杂或纳米结构的大分子,因此本文也介绍了光聚合在生物材料、表面改性和纳米复合材料领域的新兴应用。     

辐射固化涂料

201004022无臭光固化涂料组合物,套印及其生产：适用于在电子照相印刷上形成套印涂层的光固化涂料组合物含阳离子可聚合含硅的聚合物、阳离子光聚合引发剂和阳离子可聚合化合物。     

二苯基碘(钅翁)氟硼酸盐引发AGE阳离子光聚合与光交联的研究

用合成的二苯基碘(钅翁)氟硼酸盐作为光敏引发剂,研究了含乙烯基和环氧基两种不同官能基的烯丙基缩水甘油醚(AGE)的阳离子光聚合和聚合前后微观结构的变化,讨论了其阳离子光聚合的特征和机理,测定了光聚合引起光交联的凝胶转化率曲线.     

混杂光固化性能更优异

紫外光（UV）固化是一种免溶剂的环保型技术,具有固化速度快（0．1～10S）、能量消耗低、环境污染小、能自动化生产、适用于热敏材料等优点。UV固化按光固化机理分为自由基固化和阳离子固化。自由基固化是在光引发下产生的自由基,引发预聚物和单体上的双键产生聚合反应,具有固化速度快（〈10s）、性能易调节、引发剂种类多等优点,但存在的问题是不易表干、体积收缩大、粘附力差、无后固化作用等。阳离子固化是阳离子引发剂在光照射后产生质子酸或路易斯酸,形成正离子活性中心,引发阳离子开环聚合。     

UV涂料用活性稀释剂研究进展

简单介绍了紫外光固化涂料的固化原理,重点综述了应用于自由基、阳离子固化体系及混杂体系中活性稀释剂的研究进展。指出开发原料来源广泛、毒性低、价格适中,拥有高转化率、高聚合速率等优良性能的稀释剂,是未来UV涂料用稀释剂的发展方向。     

阳离子淀粉的生产与应用

介绍了阳离子淀粉的合成方法,湿法和干法。干法具有工艺简单、节省能源、无污染,是环境友好型的理想方法,可以制备各种不同高、中、低取代度的阳离子淀粉。综述了其在造纸、水处理等方面的应用,阳离子淀粉作为以淀粉为基本原料合成的绿色化学品,市场前景非常广阔。     

脂环族环氧树脂及其在阳离子UV固化中的应用

脂环族环氧树脂除具有传统环氧树脂的特性外,其粘度低、工艺操作性好,耐热性高,固化收缩小,电性能好,耐紫外线及耐候性好等独有特点,使得其在紫外光固化涂料和油墨、电力绝缘材料、复合材料、胶黏剂、电子灌封等各个行业的应用需求逐年增加,是一种应用前景很好的树脂。     

Study of the effect of hyperbranched polyols on cationic UV curable coating properties

Cycloaliphatic epoxide‐based cationic UV curable coatings containing three different hyperbranched polyols (HBPs) were systematically formulated and characterized. Polyether polyols were found to deter epoxide conversion under low UV intensity. For high UV intensity, the cycloaliphatic epoxide conversion increased with polyol content. Coatings with HBPs had better flexibility and solvent resistance than those containing a reference triol. Compared to the triol and polyester HBPs, polyether HBPs imparted lower T_g and hardness but a better flexibilizing effect to the coatings. At higher R values, the coating solvent resistance decreased except for those with one polyether HBP. A two‐peak phenomenon was discovered in the residual thermal reaction heat curve after photoDSC experiments. These two peaks were found to be related to the thermal relaxation behavior of the photocured inhomogeneous film, and the reactivation and reaction of the ‘trapped living cationic species’. The capability of the polyol to lower the high‐temperature‐peak temperature corresponded well with the flexibilizing ability. Copyright © 2006 Society of Chemical Industry     

Composition and long‐term stability of polyglycidol prepared by cationic ring‐opening polymerization

Polyglycidol synthesized by cationic ring‐opening polymerization of glycidol (boron trifluoride initiation in dichloromethane) was purified of low molecular weight contaminants by centrifugal filtration. The high and low molecular weight fractions were characterized by NMR, GPC, osmometry, viscometry, DSC, and FTIR. The ¹³C‐NMR spectrum of this polymer was completely annotated by proposing a new step in the reaction mechanism. The four thermal dimers of glycidol were also isolated and identified as 2,5‐bis(hydroxymethyl)‐1,4‐dioxane and 2,6‐bis(hydroxymethyl)‐1,4‐dioxane, each of which can exist in cis and trans configurations. Polyglycidol was found to be hygroscopic, picking up about 5% by weight of atmospheric moisture. It was also found that, over time (ca. 1–2 years), polyglycidol crosslinks into a rubbery, insoluble mass. It is therefore recommended that this polymer be stored dry and used within a few months of synthesis. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1344–1351, 2004     

阳离子单体的开发与应用

本文介绍了系列阳离子CHA、QSA、DMC的合成方法。研制的CHA有机杂质含量低,颜色浅;QSA醚化反应率高,产品糊液稳定;DMC工艺已建成300t/a规模的生产装置,产品质量指标达到国外同类产品水平。3种阳离子单体在造纸、油田、水处理、洗涤等方面有广泛的应用,具有良好的社会和经济效益。     

Anionic/Cationic Membranes Obtained by a Radiation Grafting Method for Use in Waste Water Treatment

Investigations were carried out on different ionic membranes, which were prepared by radiation-induced graft copolymerization. Cationic (low density polyethylene (LPDE)-g-poly(acrylic acid) (PAAc)) and cationic/anionic (LDPE-g-P(AAc/4-vinyl pyridine (4VP)) membranes) were used to elucidate the possibility of their practical use. The metal uptake via their functional groups was determined by using atomic absorption and X-ray fluorescence. The amount of metal uptake by the prepared membranes increased significantly as the pH of the metal feed solution increased (pH ≤ 5·3) and the chelated metal ions were easily desorbed by treating the membrane with 0·1 M HCl for 2h at room temperature. The maximum uptake for a given metal was higher for the cationic/anionic membranes than for the cationic ones. The selectivity of the cationic/anionic membranes towards different metals was investigated using mixtures of two or three metals in the same feed solution. The membranes showed high selectivity towards Fe(III ) ions. Characterization of the graft copolymers containing metals was determined by thermogravimetric analysis (TGA) and X-ray diffraction (XRD). TGA results showed that the decomposition of the graft copolymer in the presence of chelated metal ion occurred at temperatures above 300°C. The XRD of LDPE-g-P(AAc/4VP) treated with Fe(III ) at various concentrations showed that the crystallinity decreased to a certain limiting value. The complexed copolymers could be recycled several times and showed high selectivity to the Fe(III ) ion in the presence of the other metal ions investigated. This may make such grafted membranes acceptable for practical use in waste water treatment. © 1997 SCI     

含杂原子多乙烯基醚化合物的最新进展

阳离子聚合反应是UV固化技术中的重要体系,其中乙烯基醚类化合物由于聚合速度快、聚合不易受氧气干扰、低毒、无味等优点被广泛应用在涂料、黏合剂、印刷等领域,这些应用的发展推动了新的乙烯基醚类化合物的合成研究。此外,分子中含有金属或无机元素的有机物,往往具有较为特殊的性质,本文就近几年出现的含磷、硅、氮等杂原子的乙烯基醚类化合物进行了总结。     

有机电沉积涂料的新动向

阴极电沉积涂料是 2 0世纪 70年代以来发展起来的一种新的涂装方法 ,具有挥发性有机物 (VOCs)和有害空气污染物(HAPs)含量低、防蚀能力强、漆膜质量好、涂料利用率高、适合涂装结构复杂的构件和设备等特点。介绍了近年来阴极电沉积涂料研发的新动向。它们主要集中在有机双层电涂和高分子 聚电解质 /低聚物电解质复合物多层电涂体系 ,这些新的电涂体系在涂料的稳定性以及涂层的物理化学性质和力学性能方面具有明显的改进。     

微波辅助一步法制备氧化阳离子淀粉的研究

以木薯淀粉为原料,3-氯-2-羟丙基三甲基氯化铵为阳离子醚化剂,自制碱性复合催化剂为醚化催化剂,双氧水为氧化剂,CuSO4为氧化催化剂,采用微波辅助一步法制备氧化阳离子淀粉。通过单因素实验研究醚化剂用量、碱性催化剂用量、氧化剂用量、CuSO4用量、反应温度和反应时间对粘度、取代度和反应效率的影响,并对工艺参数进行优化验证。结果表明,较佳的工艺条件为：淀粉用量200 g,醚化剂用量15 g,碱性催化剂与醚化剂摩尔比1.5,双氧水用量8 g,CuSO4用量0.09 g,反应温度90℃,反应时间18 min。在此条件下所得产品阳离子取代度（DS）为0.0414,醚化反应效率为92.87%,粘度为32.6 mPa·s（固含量12%,55℃）。本工艺制备的淀粉产品具有糊化温度低,糊液粘度低、稳定性高的特点。