A high reactive pentacoordinate organic silicon complex was at first prepared by reaction of natural silica with ethylene glycol and potassium hydroxide. Then a novel tetracoordinate silicon was synthesized by reactin...A high reactive pentacoordinate organic silicon complex was at first prepared by reaction of natural silica with ethylene glycol and potassium hydroxide. Then a novel tetracoordinate silicon was synthesized by reacting the pentacoordinate silicon with HCl. The product was characterized and analyzed by FTIR, NMR and TG/DTG.展开更多
The styrene-acrylic（St-BA-MAA/SDS-DNS86/H2O）emulsion modified by the ethyl-tetra-coordinated silicon was prepared,using water as the solvent,the laurel sodium sulfate and alkyl ethyl sulfuric acid sodium（SDS-DNS86...The styrene-acrylic（St-BA-MAA/SDS-DNS86/H2O）emulsion modified by the ethyl-tetra-coordinated silicon was prepared,using water as the solvent,the laurel sodium sulfate and alkyl ethyl sulfuric acid sodium（SDS-DNS86） as the emulsifiers potassium per-sulfate（KPS） for the initiator and adding the initiator minute steps for free radical polymerization.The thermal properties analyzed by TG and the glass transition temperature determined by DSC were researched to the styrene-acrylic emulsion and emulsions modified by ethyl-tetra-coordinated silicon.The results indicated that the thermal properties of the modified membrane increas and the glass transition temperature of the modified membrane decreases and adhesion force of the modified membrane enhances.展开更多
The high activ penta-coordinated silicon potassium compound was prepared by the reaction of amorphous silica with the ethylene glycol,catalyzed by the potassium hydroxide,and the ethyl tetra-coordinated silicon compou...The high activ penta-coordinated silicon potassium compound was prepared by the reaction of amorphous silica with the ethylene glycol,catalyzed by the potassium hydroxide,and the ethyl tetra-coordinated silicon compound was synthesized by the reaction of this penta-coordinate silicon potassium compound with allyl chloride.Then the copolymer was prepared by the reactwn of this ethyl tetra-coordinated silicon with the methyl-acrylic acid β-hydroxyl ethyl ester,and its structure and thermal property were characterized by IR,TG,DSC et al.IR indicated the reaction has finished because of no absorption near 1630cm-1.TG indicated the decomposing temperature of copolymer is 300 ℃.DSC indicated the glass transition temperature is 63.1℃.The copolymer was not soluble in any solvent and had no melt-point.All analysis proved the copolymer exists some extent linkage.展开更多
磷酸盐玻璃在光学领域有广泛的应用,然而因为简单的磷酸盐玻璃的化学稳定性和热机械性能较差,已经难以满足日益发展的激光装置的高性能要求。在磷酸盐玻璃中加入少量的硅可以形成六配位的硅网络体并且极大的改善这些性能。因此研究这种...磷酸盐玻璃在光学领域有广泛的应用,然而因为简单的磷酸盐玻璃的化学稳定性和热机械性能较差,已经难以满足日益发展的激光装置的高性能要求。在磷酸盐玻璃中加入少量的硅可以形成六配位的硅网络体并且极大的改善这些性能。因此研究这种磷硅酸盐玻璃的结构细节有重要的意义。但是由于玻璃结构缺乏长程有序,其结构研究比较复杂。现代固体核磁共振(NMR)技术能够从原子尺度对无序状态的物质局域结构进行解析,是一种强大的用来研究玻璃结构的技术手段。本文的目的是探究碱土金属对磷硅酸盐玻璃中六配位硅结构的影响。我们采用传统的熔融-冷却法制备了(2MO-3P2O5)(1−x)·(SiO2)x(M=Ca,Sr,Ba)体系的磷硅酸盐玻璃。并且运用先进的固体核磁共振技术和拉曼光谱对此磷硅酸盐玻璃结构进行了表征。31P和29Si MAS NMR表明其网络结构由磷氧四面体P(2)和P(3)与四配位和六配位的硅氧多面体相互连接构成,随着二氧化硅含量的增加六配位硅的比例呈现减少的趋势。类似地,在拉曼光谱的结构中和六配位硅相连的磷基团的峰也随着硅含量的增加而减弱。基于双量子相干和P-P同核间J耦合作用的重聚INADEQUATE实验证明了不同的磷氧四面体之间的连接情况,P(2)和P(3)两种结构单元在玻璃中是相对分离的,他们大多数都是与自身相连接。和之前报道的有关Na2OP2O5-SiO2体系的玻璃相比较,不同的是,在Na2O-P2O5-SiO2玻璃中一个P(3)结构单元最多有一个Si(6)-O-P(3)键,而对于本文的碱土金属磷硅酸盐玻璃一个P(3)结构单元最多有0.4–0.7个Si(6)-O-P(3)键。说明碱土金属比碱金属对六配位硅的稳定作用更弱一些。这种结构与组成之间的关系对设计玻璃组成和性质能提供重要的依据,尤其在大型的激光装置中对磷酸盐玻璃基质的化学和热稳定性有着很高的要求,详细的结构信息能为通过改变组成来提高善玻璃性能搭建桥梁。展开更多
在查明凹凸棒石矿石矿物组成的基础上,系统采集明光市官山采矿场剖面样品,选择典型矿石样品,利用X射线衍射（XRD）、29Si魔角旋转核磁共振（29 Si MAS-NMR）对不同温度煅烧前后凹凸棒石结构研究,结合热重分析以及程序升温凹凸棒石脱水曲...在查明凹凸棒石矿石矿物组成的基础上,系统采集明光市官山采矿场剖面样品,选择典型矿石样品,利用X射线衍射（XRD）、29Si魔角旋转核磁共振（29 Si MAS-NMR）对不同温度煅烧前后凹凸棒石结构研究,结合热重分析以及程序升温凹凸棒石脱水曲线,认识热处理凹凸棒石结构演化规律,为凹凸棒石黏土加工和应用提供理论依据。结果表明：在240℃左右脱除结构中一半的结晶水,晶体结构发生调整,晶体内部孔道出现折叠;在430℃左右脱除另外二分之一结晶水,同时脱出晶体内部结构水和外表面结构水,晶体结构周期性基本破坏;凹凸棒石在500～700℃温度区间热处理后处于非晶化状态,但是c轴方向的部分有序性仍然存在,硅氧四面链尚没有解体;凹凸棒石脱出结构中一半的结晶水后,经过水化后可以恢复到原来的结构状态,超过350℃热处理凹凸棒石脱出更多的结构水后不能通过水化作用恢复到原来的结构状态。展开更多
文摘A high reactive pentacoordinate organic silicon complex was at first prepared by reaction of natural silica with ethylene glycol and potassium hydroxide. Then a novel tetracoordinate silicon was synthesized by reacting the pentacoordinate silicon with HCl. The product was characterized and analyzed by FTIR, NMR and TG/DTG.
文摘The styrene-acrylic（St-BA-MAA/SDS-DNS86/H2O）emulsion modified by the ethyl-tetra-coordinated silicon was prepared,using water as the solvent,the laurel sodium sulfate and alkyl ethyl sulfuric acid sodium（SDS-DNS86） as the emulsifiers potassium per-sulfate（KPS） for the initiator and adding the initiator minute steps for free radical polymerization.The thermal properties analyzed by TG and the glass transition temperature determined by DSC were researched to the styrene-acrylic emulsion and emulsions modified by ethyl-tetra-coordinated silicon.The results indicated that the thermal properties of the modified membrane increas and the glass transition temperature of the modified membrane decreases and adhesion force of the modified membrane enhances.
文摘The high activ penta-coordinated silicon potassium compound was prepared by the reaction of amorphous silica with the ethylene glycol,catalyzed by the potassium hydroxide,and the ethyl tetra-coordinated silicon compound was synthesized by the reaction of this penta-coordinate silicon potassium compound with allyl chloride.Then the copolymer was prepared by the reactwn of this ethyl tetra-coordinated silicon with the methyl-acrylic acid β-hydroxyl ethyl ester,and its structure and thermal property were characterized by IR,TG,DSC et al.IR indicated the reaction has finished because of no absorption near 1630cm-1.TG indicated the decomposing temperature of copolymer is 300 ℃.DSC indicated the glass transition temperature is 63.1℃.The copolymer was not soluble in any solvent and had no melt-point.All analysis proved the copolymer exists some extent linkage.
文摘磷酸盐玻璃在光学领域有广泛的应用,然而因为简单的磷酸盐玻璃的化学稳定性和热机械性能较差,已经难以满足日益发展的激光装置的高性能要求。在磷酸盐玻璃中加入少量的硅可以形成六配位的硅网络体并且极大的改善这些性能。因此研究这种磷硅酸盐玻璃的结构细节有重要的意义。但是由于玻璃结构缺乏长程有序,其结构研究比较复杂。现代固体核磁共振(NMR)技术能够从原子尺度对无序状态的物质局域结构进行解析,是一种强大的用来研究玻璃结构的技术手段。本文的目的是探究碱土金属对磷硅酸盐玻璃中六配位硅结构的影响。我们采用传统的熔融-冷却法制备了(2MO-3P2O5)(1−x)·(SiO2)x(M=Ca,Sr,Ba)体系的磷硅酸盐玻璃。并且运用先进的固体核磁共振技术和拉曼光谱对此磷硅酸盐玻璃结构进行了表征。31P和29Si MAS NMR表明其网络结构由磷氧四面体P(2)和P(3)与四配位和六配位的硅氧多面体相互连接构成,随着二氧化硅含量的增加六配位硅的比例呈现减少的趋势。类似地,在拉曼光谱的结构中和六配位硅相连的磷基团的峰也随着硅含量的增加而减弱。基于双量子相干和P-P同核间J耦合作用的重聚INADEQUATE实验证明了不同的磷氧四面体之间的连接情况,P(2)和P(3)两种结构单元在玻璃中是相对分离的,他们大多数都是与自身相连接。和之前报道的有关Na2OP2O5-SiO2体系的玻璃相比较,不同的是,在Na2O-P2O5-SiO2玻璃中一个P(3)结构单元最多有一个Si(6)-O-P(3)键,而对于本文的碱土金属磷硅酸盐玻璃一个P(3)结构单元最多有0.4–0.7个Si(6)-O-P(3)键。说明碱土金属比碱金属对六配位硅的稳定作用更弱一些。这种结构与组成之间的关系对设计玻璃组成和性质能提供重要的依据,尤其在大型的激光装置中对磷酸盐玻璃基质的化学和热稳定性有着很高的要求,详细的结构信息能为通过改变组成来提高善玻璃性能搭建桥梁。
文摘在查明凹凸棒石矿石矿物组成的基础上,系统采集明光市官山采矿场剖面样品,选择典型矿石样品,利用X射线衍射（XRD）、29Si魔角旋转核磁共振（29 Si MAS-NMR）对不同温度煅烧前后凹凸棒石结构研究,结合热重分析以及程序升温凹凸棒石脱水曲线,认识热处理凹凸棒石结构演化规律,为凹凸棒石黏土加工和应用提供理论依据。结果表明：在240℃左右脱除结构中一半的结晶水,晶体结构发生调整,晶体内部孔道出现折叠;在430℃左右脱除另外二分之一结晶水,同时脱出晶体内部结构水和外表面结构水,晶体结构周期性基本破坏;凹凸棒石在500～700℃温度区间热处理后处于非晶化状态,但是c轴方向的部分有序性仍然存在,硅氧四面链尚没有解体;凹凸棒石脱出结构中一半的结晶水后,经过水化后可以恢复到原来的结构状态,超过350℃热处理凹凸棒石脱出更多的结构水后不能通过水化作用恢复到原来的结构状态。
