Rate-accelerating of Boric Oxide for Atom Transfer Radical Polymerization of Styrene

联系人简介: 邹友思, 男, 教授, 博士生导师, 主要从事活性自由基聚合研究. E-mail [email protected][中文文摘]以2-溴丙酸乙酯为引发剂,溴化亚铜为催化剂,N,N,N′,N″,N″-五甲基二乙基三胺为配体,以氧化硼为加速剂,进行了苯乙烯原子转移自由基聚合的加速研究.发现氧化硼与引发剂比例为4时,加速效果最为明显,且对分子量的控制效果较好.在85℃时,添加该比例的氧化硼,苯乙烯在6 h的聚合转化率达到78.5%.在65,75及85℃条件下,加入氧化硼时体系的聚合反应动力学为一级反应,苯乙烯聚合速率分别为空白体系的1.82,1.54和1.5倍;聚合物的分子量可控,分子量分布窄,体系呈现明显的活性聚合特征.通过核磁共振谱对聚合物的结构进行了表征,证明氧化硼在整个聚合过程中只起加速作用,并不影响聚合机理和聚苯乙烯的结构.氧化硼价廉,有利于实现原子转移聚合的工业化.[英文文摘]The polymerization of styrene was mediated by copper(Ⅰ) bromide/pentramethyltriamine(PMDETA) using ethyl 2-bromopropionate(EBP) as an initiator and boric oxide(BO) as a rate-accelerating additive.BO was found to be effective to accelerate ATRP of styrene,and the conversions were improved to 78.5% during 6 h at 85 ℃.An optimal molar ratio of BO/EBP for the polymerization of styrene was 4∶1.First-order kinetics,increase of Mn with respect to conversion,and the relatively narrow polydispersity demonstrate that the polymerization of styrene in the presence of BO proceeds in a living fashion. The apparent rate constant of polymerization was improved by a factor of 1.82, 1.54 and 1.5 at 65,75 and 85℃ respectively NMR spectra study indicates that no influence occurred on the structure of polysty rene when BO w as added as promo ter. BO is likely to solve the slow polymerization rate of ATRP and promote its industrial application

Preparation, Light-Dimming and Heat-Insulating Properties of Nano-SiO2 Cryogels-ATO Composite Filmed Glass

Nano-silica cryogels and ATO composite dispersion were coated on PET film, and then the coated film was pasted on the glass to prepare filmed glass. The optical and thermal insulation properties of the filmed glass were investigated. The results showed t

Study of Rate-accelerating of Aluminum Hydroxide,Boric Acid,and(2-Methylpropyl)Boronic Acid for Atom Transfer Radical Polymerization of Styrene

通讯作者:[email protected][中文文摘]以2-溴丙酸乙酯(EBP)为引发剂,溴化亚铜(CuBr)为催化剂,N,N,N′,N″,N″-五甲基二乙基三胺(PMDETA)为配体,选择了3种路易斯酸(LA),即氢氧化铝(AH)、硼酸(BA)、异丁基硼酸(MPBA)为加速剂,对苯乙烯(St)原子转移自由基聚合的加速进行了研究.结果表明,在80℃下,氢氧化铝、硼酸、异丁基硼酸对苯乙烯原子转移自由基聚合均具有明显的加速效果,发现当[AH]/[EBP]=5、[BA]/[EBP]=4[、MPBA]/[EBP]=5时,加速效果最为明显,且对分子量的控制效果较好,特别是异丁基硼酸在设计分子量较大范围内仍具有明显的加速,且控制效果好.[英文文摘]The polymerization of styrene was mediated by copper(I) bromide/pentramethyl diethyl-triamine(PMDETA) using ethyl 2-bromopropionate(EBP) as initiator and a catalytic amount of Lewis acid(LA),such as aluminum hydroxide(AH),boric acid(BA),and(2-methylpropyl)boronic acid(MPBA),as a rate-accelerating additive.The polymerization in the presence of LA proceeded in a living fashion indicated by the first-order kinetic plots,with increase of Mn with respect to conversion and the relatively narrow polydispersities and had a apparent rate2enhancement efficiency. It was found that the polymerization was cont rolled well and had significant rate enhancements when the molar ratio of [AH]/[EBP]=5∶1,[BA ]/[EBP]=4∶1 , [MPBA ]/[EBP]=5∶1,respectively. And particularly ,the rate of polymerization of styrene with the optimal ratio of [MPBA ]/[ EBP](5∶1) was remarkably enhanced and a good controllability was maintained in the molecular weight from 10 000 to 100 000

Rate-accelerating of Boric Oxide for Atom Transfer Radical Polymerization of Styrene

The polymerization of styrene was mediated by copper (I) bromide/pentramethyltriamine (PMDETA) using ethyl 2-bromopropionale(EBP) as an initiator and boric oxide(BO) as a rate-accelerating additive. BO was found to be effective to accelerate ATRP of styrene, and the conversions were improved to 78.5% during 6 h at 85 degrees C. An optimal molar ratio of BO/EBP for the Polymerization of styrene was 4:1. First-order kinetics, increase of M,, with respect to conversion, and the relatively narrow polydispersity demonstrate that the polymerization of styrene in the presence of BO proceeds in a living fashion. The apparent rate constant of polymerization was improved by a factor of 1.82, 1.54 and 1.5 at 65, 75 and 85 degrees C respectively. NMR spectra study indicates that no influence occurred on the structure of polystyrene when BO was added as promoter. BO is likely to solve the slow polymerization rate of ATRP and promote its industrial application

南海张裂过程及其对晚中生代以来东南亚构造的启示——IODP建议书735-Full介绍

南海的形成揭示了大陆边缘张裂和盆地形成的复杂模式，尽管已经进行了广泛研究，但是关于基底岩石和深海盆沉积层的精确年代数据还很缺乏，这使得对南海张裂年代的估计存在很大的误差，对张裂机制和历史的各种假设没有得到验证。同时只有对南海的张裂过程有了精确地分析与刻画，才能更好地理解西太平洋边缘海盆地的形成以及它们在印支块体受印度－欧亚板块碰撞而向东南挤出、青藏高原隆升中可能起到的作用。2009年正式提交的国际综合大洋钻探计划（IODP）建议书735－Full建议在南海深海盆内的4个站位上实施钻探。这4个站位分布在南海盆地4个不同的次级构造单元上（南海东北部、西北次海盆、东部次海盆和西南次海盆），这样的站位设计会确保完成本建议书的整体研究目标，即揭示南海的张裂历史和它对晚中生代以来东南亚构造的启示。位于南海盆地最东北部的站位有助于确定该区域地壳的属性和验证古南海是否存在，位于西北次海盆的站位可能会提供南海的最早张裂年代，另外2个分别位于东部次海盆和西南次海盆的站位将重点确定2个次海盆的绝对年龄、基底矿物成分与磁化率以及2个次海盆的相对张裂次序。这些站位的水深大约在2910～4400m，钻探深度预计到海底以下大约700～2200m，总的钻透深度为5959m，其中5359m穿透沉积层，另外600m或400m钻入基底。所有这些站位的位置是由已有的地球物理观测数据所确定，目前计划收集更多的地质与地球物理数据以满足IODP对井位调查数据的要求