1,3-双(二甲基羟基硅基)-2,2,4,4-四甲基环二硅氮烷的合成

通过1,3-双（二甲基氯硅基）-2,2,4,4-四甲基环二硅氮烷的水解反应合成了1,3-双（二甲基羟基硅基）-2,2,4,4-四甲基环二硅氮烷。初步探讨了反应的条件。产物收率达到92％。并经红外光谱和X射线衍射表征产物结构。     

1,4-双(4-氟苯甲酰基)苯的合成与纯化

芳香族卤代物是制备高分子材料聚芳醚酮所需单体之一。通过付-克酰化反应合成了一种芳香族卤代物1,4-双(4-氟苯甲酰基)苯,并探讨影响反应产率的因素。通过熔点测定、红外光谱(IR)和核磁共振谱(HNMR)等方法,确证了这种化合物的结构和纯度。     

微波合成1,4-二(吡唑基-1-亚甲基)苯

以二甲基亚砜为溶剂,1,4-对二氯苄和吡唑为反应物,微波辐射合成了1,4-二(吡唑基-1-亚甲基)苯。通过实验研究确定最佳合成条件为:微波输出功率为400W、间歇辐射时间为4min、n(吡唑)∶n(对二氯苄)=2.2∶1。最佳条件下产率可达79.6%。经元素分析及IR、1 H NMR表征,确认了合成产物结构。     

4,4'-双(二甲基-锂氧硅基)苯醚引发八甲基环四硅氧烷聚合

用4,4'-双(二甲基-羟基硅基)苯醚与正丁基锂反应制备4,4'-双(二甲基-锂氧硅基)苯醚(LiPE)。以LiPE为引发剂,N,N-二甲基甲酰胺为促进剂,使八甲基环四硅氧烷(D4)开环聚合制备了聚二甲基硅氧烷。实验表明,当LiPE质量分数为D4用量的0.20%～0.35%,反应温度为(155±5)℃,反应时间为3h时,可制得特性黏数大于90mL/g的聚二甲基硅氧烷。     

1,4-双(2-苯并咪唑基)苯的合成和荧光性质改进

以多聚磷酸与磷酸的混合酸为催化剂,由对苯二甲酸与邻苯二胺缩合,合成了1,4-双(2-苯并咪唑基)苯,收率为87.7%.通过各种试验,得到的优化反应条件为:催化剂中多聚磷酸与磷酸的体积比为1∶4,反应物料配比为n(对苯二甲酸):n (邻苯二胺)=1∶2.2,反应温度为200 ℃, 反应时间为6 h.产物经元素分析、IR谱、1HNMR谱表征,同时发现固体产物发射很强的紫色荧光,荧光寿命为0.52 ns.通过将稀土金属离子Er3+与1,4-双(2-苯并咪唑基)苯配位,大大改进其原有的荧光性质,Er(Ⅲ)配合物发射蓝色荧光,荧光强度增大到原化合物的3倍,荧光寿命也增加到0.99 ns.     

双(2-苯并咪唑基)苯系列化合物的合成

用邻苯二胺分别和邻、间、对苯二甲酸为原料,在氮气保护条件下,采用磷酸作催化剂,合成了一系列的双(2-苯并咪唑基)苯系列化合物1,2-双(2-苯并咪唑基)苯(OBMB)、1,3-双(2-苯并咪唑基)苯(BBM)和1,4-双(2-苯并咪唑基)苯(PBIB),主要讨论了催化剂、反应温度、物料比对产率的影响。     

二甲基苯基硅氧基封端聚(二甲基-甲基苯基)硅氧烷共聚物的热分解性能及动力学研究

以1,1,3,3-四甲基二苯基二硅氧烷为封端剂,八甲基环四硅氧烷与甲基苯基环硅氧烷混合物为共聚单体,在阴离子催化剂作用下合成了二甲基苯基硅氧基封端的聚(二甲基-甲基苯基)硅氧烷共聚物.采用非等温TG技术,在惰性气氛和5.0、10.0、15.0和40.0 K·min-1线性升温速率条件下,考察了共聚物非等温热降解机理及反应动力学,采用Friedman-Reich-Levi、Flynn-Wall-Ozawa和Kissinger等方法对非等温动力学数据进行分析,所得平均表观活化能分别为113.64、115.69和145.80 kJ·mol-1.采用等转化率法确定出共聚物热分解反应符合Avrami-Erofeev方程,反应机理为随机成核和随后生长.采用Crane和Doyle方法研究了不同升温速率对反应级数、活化能和指前因子的影响,结果表明降解反应为一级反应,反应活化能介于152.46～183.13 kJ·mol-1之间,指前因子介于4.25×109～4.02× 109 s-1.同时采用等温TG技术得到失重5％和10％条件下的寿命方程,对共聚物的寿命进行了预测.     

2,2’-双(4-氰氧苯)基丙烷的制备

主要研究了通过溴化氰途径合成 2 ,2’ 双 ( 4 氰氧苯 )基丙烷 ,指出了优化化工艺条件 ,产品质量分数达 99%以上 ,产率达 85 %以上。     

碳-碳偶合反应合成1,4-双[β-(p-邻苯二甲酸酐)乙炔基]苯

以1,4-二乙炔基苯和4-溴邻苯二甲酸酐为原料,通过碳-碳偶合反应生成1,4-双[β-(p-邻苯二甲酸酐)乙炔基]苯,经40% HCl溶液水解成1,4-双[β-(p-邻苯二甲酸)乙炔基]苯,再经与乙酸酐回流得到目标产物.探讨原料物质的量比、芳卤试剂、溶剂、反应温度、催化剂、共催化剂等因素对目标产物产率的影响,并用元素分析、DSC、IR和1HNMR等手段对产物的组成和结构进行表征.     

双(三甲基硅基)二亚胺的合成研究

以双(三甲基硅基)氨基锂为起始原料,分别与氯化亚砜、三溴化磷反应,合成了双(三甲基硅基)硫二亚胺和双(三甲基)硅胺基-三甲基硅亚氨基磷,然后通过两者间的硫原子迁移反应,合成了标题化合物.通过梯度温度下的减压冷凝,实现了目标化合物的分离和纯化,并采用核磁共振、紫外-可见吸收光谱进行了结构表征,根据最大吸收波长计算得其跃迁能为2.53 ×10-19J.     

对苯二甲基二甲醚的制备

以对二氯苄为原料,与甲醇钠反应合成了对苯二甲基二甲醚,对其工业化生产工艺进行了优化。     

Gas Permeation Properties of Copolyimides from 1,4-Bis(3,4-dicarboxyphenoxy)benzene Dianhydride and 2,2-Bis(3,4- dicarboxyphenyl)hexafluoroisopropane Dianhydride

A series of aromatic copolyimides was prepared from 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride (HQDPA) and 2,2-bis(3,4-dicarboxy-phenyl)hexafluoroisopropane dianhydride (6FDA) with 3,3′-dimethyl-4,4′-methyl-ene dianiline (DMMDA) by a chemical imidization. The gas permeability coefficients of the copolyimides to H₂, CO₂, O₂, N₂ and CH₄ were measured under 7atm. pressure. The fractional free volume of 6FDA–DMMDA is larger than that of HQDPA–DMMDA, while the chain segmental mobility of 6FDA–DMMDA is lower than that of HQDPA–DMMDA. The gas permeability of 6FDA–DMMDA is much higher than that of HQDPA–DMMDA but the perm-selectivity of 6FDA–DMMDA for H₂, CO₂, O₂, N₂ over CH₄ is lower than that of HQDPA–DMMDA. The experimental values of the gas permeability coefficients of the copolyimides are in satisfactory agreement with the values estimated from the gas permeability coefficients of the constituent homopolyimides and their weight fractions. © of SCI.     

Synthesis and Characterization of Polyamides Derived From Cyano-Containing 1,4-Bis(4-aminophenoxy)benzene Monomers

Summary A series of potentially electroactive aromatic-aliphatic polyamides based upon 3,6-bis(2-cyano-4-aminophenoxy)phthalonitrile (1) was synthesized in N,N-dimethylacetamide to yield polymers with intrinsic viscosities of 0.66-1.04 dL/g. One polyamide was synthesized using 1,4-bis(2-cyano-4-aminophenoxy)benzene (2) to compare to 1. There appears to be an odd-even effect of methylene spacer length upon the mechanical properties and glass transition temperature, with an even number of methylene groups yielding the larger values. Thermogravimetric analysis in air and nitrogen showed that these polymers had similar 5% weight losses in both atmospheres, which indicated that oxygen is not involved in the initial degradation of these polymers.     

Synthesis and Characterization of Polyimides Derived From Cyano-Containing 1,4-Bis(4-aminophenoxy)benzene Monomers

Summary A series of three new cyano-containing diamines based upon 1,4-bis(4-aminophenoxy)benzene was synthesized and polymerized with six different dianhydrides to yield 18 different polyimides. Due to the high dipole moment of the cyano group, it was believed that these polymers would display differing degrees of electroactivity depending upon the degree and position of cyano substitution. The type of dianhydride bridging group and length are also factors that affect the electroactivity of polyimides. Polyimides based upon 1,4-bis(4-aminophenoxy)benzene were used as reference materials by which the respective cyano-containing analogs were compared. As the degree of cyano group substitution increased, the glass transition temperature increased. As cyano substitution increased, the polymer chain flexibility decreased due to hindered rotation about the phenyl-ether-phenyl linkages in the diamine portion of the polymer. The tensile moduli ranged from 2.97 to 4.57 GPa and ultimate tensile strengths from 79 to 156 MPa, which are typical values of aromatic polyimides.     

Synthesis and photodegradation of poly[1,4-bis(dimethylsilyl)naphthalene]

Summary Poly[1,4-bis(dimethylsilyl)naphthalene](I), a copolymer with alternating 1,4-naphthalene and disilyl units, has been prepared by the Wurtz coupling of 1,4-bis(dimethylchlorosilyl) naphthalene (II) or 1,4-bis(dimethylfluorosilyl)naphthalene (III) with sodium metal dispersion in toluene. The molecular weight distribution of I prepared from III is significantly higher than when I is prepared from II. I has been characterized by ¹H, ¹³C and ²⁹Si NMR, IR, UV, GPC, TGA and elemental analysis. Photolysis of I in benzene/methanol solution results in rapid degradation of I.     

超声波辐射合成双苯并咪唑

以磷酸和多聚磷酸为催化剂,邻苯二胺和草酸为原料,在超声波辐射下合成双苯并咪唑,并利用正交法探索最佳反应条件。通过实验探索得最佳反应条件为：配料比（邻苯二胺与草酸物质的量比）1：3.0,反应时间6 h,反应温度40℃,多聚磷酸和磷酸（1：1）为催化剂,收率为15.67%。     

1,2-双(3-甲氧羰基-2-硫脲基)苯的催化合成

研究了１１种催化剂对１,２ 双（３ 甲氧羰基 ２ 硫脲基）苯的合成性能的影响,筛选得出催化剂（对氨基二甲苯胺∶Ｎ,Ｎ 二甲基苯胺∶Ｎ,Ｎ 二甲基十八胺＝１∶６∶３,质量比）,在所给定的反应条件下（催化剂用量为反应物总质量的２％,时间６０ｍｉｎ,温度２５～３５℃）,可使产物收率（相对邻苯二胺）达８８％以上,纯度达９８％以上。     

超声辐射下2-苯基吲哚的合成

以邻硝基甲苯为原料合成了2-苯基吲哚。在乙醇钠催化下邻硝基甲苯与草酸二乙酯缩合，经水解、双氧水氧化、盐酸酸化得到邻硝基苯乙酸，收率为62％。邻硝基苯乙酸与PCl3在苯中回流2h，得邻硝基苯乙酰氯；在超声辐射下AlCl3催化邻硝基苯乙酰氯与苯反应10min得到2-（2-硝基苯基）-1-苯基乙酮，收率76％。在乙醇中，超声辐射下Pd／C催化次磷酸钠还原2-（2-硝基苯基）-1-苯基乙酮10min得到2-苯基吲哚。收率95％。总收率45％。