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1.
新型树状大分子核醚-四硅烷的合成   总被引:4,自引:0,他引:4  
以季戊四醇为原料合成了一种新型树状大分子核--醚-四硅烷,可用于树状大分子构筑.通过季戊四醇(1)与溴丙烯的醚化反应得到四烯丙基醚2,然后在Pt催化作用下,2与硅氯仿通过硅氢化反应生成醚-四(三氯硅烷) 3(可直接与多种官能团反应生成树状大分子),3经过LiAlH4还原后得到目标产物醚-四硅烷4.通过IR, 1H NMR, 13C NMR对中间体和目标产物的结构进行了表征,并对产物的结构进行了讨论和确认.  相似文献   

2.
基于官能团非等活性原理,由商品化多组分单体一步法合成了超支化聚合物. 用苯—1,2,4-三羧酸—1,2酐(BTAA)与羟乙基哌嗪(HEPZ)为原料,利用氨基和羟 基反应活性不同,制备了结构非对称超支化聚酰胺—酯.分别用红外、核磁共振确 定了所得聚合物的结构.该聚合物分子骨架中含有交替排列的酰胺键、叔氨和酯键 ,易溶于水.本合成方法原料易得、工艺简单,适合大量制备超支化聚合物.  相似文献   

3.
以2,6-二氯嘌呤为原料,分别采用硫脲分步法、硫脲一步法和硫氢化钾法合成2-氯-6-巯基嘌呤(化合物1),比较不同方法的特点以及对产物收率的影响。结果表明,采用硫氢化钾法合成路线,可以使产物收率达到96. 5%,而且产物纯度好,后处理简单。以化合物1为原料,进一步合成了2-氯-6-苄硫基嘌呤(化合物2)以及三种2-芳胺基-6-巯基嘌呤衍生物(3a~3c),并研究了微波辐射对2-[(4-苄氧基)苯胺基]-6-巯基嘌呤(3c)合成反应的影响,结果表明,微波辐射可以有效提高反应速率,缩短反应时间,产率提高到66. 3%。产物结构经1H NMR表征。  相似文献   

4.
朱家艺  贺军辉 《化学学报》2010,68(10):961-968
通过改变反应物物质的量比、分散相与连续相体积比、反应体系温度和煅烧后处理温度,研究了反应条件对乳液法自组装合成氧化锰纳米粒子结构、形貌和尺寸的影响.结果表明:当高锰酸钾与油酸物质的量比在1∶5~1∶1之间时,形成蜂窝状纳米粒子和空心纳米粒子;当分散相(油酸)与连续相(水)的体积比为4∶200时,形成良好的空心球纳米结构;反应体系温度升高不利于产物的洗涤;不同温度的煅烧后处理不仅影响氧化锰纳米粒子的形貌,而且影响其结晶度和晶型.  相似文献   

5.
通过酰胺化反应在大豆分离蛋白(SPI)表面引入溴原子,合成了大分子引发剂SPI-Br,以CuCl和bpy为催化体系,通过原子转移自由基聚合法(ATRP)合成了大豆分离蛋白-g-聚甲基丙烯酸2-羟乙酯(SPI-g-PHEMA).用FTIR1、3C-NMR、GPC对大分子引发剂、接枝产物和接枝物降解链进行结构表征.结果表明,得到了表面接枝聚甲基丙烯酸2-羟乙酯长链的大豆分离蛋白接枝聚合物,用紫外分光光度计(UV)、荧光分光光度计z、eta电位和透射电镜(TEM)表征了接枝产物的溶液性质和微观形态.  相似文献   

6.
首先通过发散法合成出1.0G~5.0G聚酰胺-胺树枝状大分子PAMAM;然后利用氨基与醛的脱水缩合反应,用水杨醛对大分子进行修饰合成出(聚酰胺-胺)-水杨醛席夫碱树枝状大分子配体PAMAMSA;再通过PAMAMSA与氯钯酸锂在甲醇中反应制得一系列钯配合物PAMAMSA-Pd.用红外光谱、核磁共振谱、热重-差热法对所合成的材料结构组成进行了表征与确证.研究了在纯水介质中PAMAMSA-Pd作为催化剂前躯体对碘代苯及其衍生物与丙烯酸Heck交叉偶联反应的催化性能,并比较了钯配合物和PdCl2的催化活性,结果表明树枝状大分子催化剂显示出良好的催化活性,其中1.0G PAMAMSA-Pd和5.0G PAMAMSA-Pd的活性较高.  相似文献   

7.
以Boc-(4R)-羟基-(2S)-脯氨酸为原料,在NaH作用下与苄位溴代试剂发生醚化反应,合成了几种4-取代-L-脯氨酸类手性催化剂,即在(4R)-羟基-(2S)-脯氨酸的4-位上引入不同的苄氧基以期提高其催化活性和脂溶性,并通过1 H NMR、13 C NMR和HRMS对合成产物的结构进行表征,确定其为目标产物.实验结果还表明,当苯环上连有强的吸电子基团时反应很难进行,而当连有给电子基团时反应相对较容易进行且反应条件较温和.  相似文献   

8.
将二官能度单体(A2)和三官能度单体(BB2¢)反应合成超支化聚合物的方法推广应用于共聚反应.用A2 ——二乙烯基砜(DV),B2 ——4,4′-三亚甲基二哌啶(TMDP)和BB2¢——N-乙基乙二胺(NDA)单体直接反应合成了超支化共聚物.聚合反应时,TMDP和NDA的仲胺基与DV的双键迅速加成,生成一种带有双键和伯胺基的AB2¢型中间体,该中间体进一步聚合得到超支化聚砜胺.用Fourier变换红外光谱(FTIR),色-质联用谱(LC/MSD)等测试手段验证了这一反应机理.产物的支化度随着TMDP与NDA的加料比增大而减小,因而可通过这种共聚合方法来控制超支化聚合物的支化度.当TMDP与NDA的加料比大于或等于4时,产物是半结晶的.  相似文献   

9.
采用开环聚合、发散法以及"点击化学法"合成了线型-树状聚两性电解质.首先通过γ-苄基-L-谷氨酸酯羧酸酐(BLG-NCA)的开环聚合及发散合成法分别合成了叠氮端基聚(γ-苄基-L-谷氨酸酯)(PBLG-N3)及以炔基为内核的带有4个伯氨端基的第2.0代聚酰胺-胺(PAMAM-D2),再将二者通过"点击反应"制备的线型-树状嵌段共聚物PBLG-b-D2作为大分子引发剂,利用其末端氨基引发ε-苄氧羰基-L-赖氨酸羧酸酐(ZLL-NCA)的开环聚合,获得线型-树状嵌段共聚物PBLG-b-D2-(PZLL)4,再经酸解脱除PBLG上的苄基及PZLL上的苄氧羰基,获得目标产物聚(L-谷氨酸)-b-聚[酰胺-胺-聚(L-赖氨酸)](PLGA50-b-D2-(PLL9)4)线型-树状聚两性电解质.通过核磁(1H-NMR)、傅里叶变换红外光谱(FTIR)和凝胶渗透色谱(GPC)表征了聚合物分子结构、分子量及其分布;通过电导滴定法、1H-NMR、zeta电位、激光光散射(LLS)、扫描电子显微镜(SEM)及圆二色谱(CD)等方法研究了PLGA50-b-D2-(PLL9)4对溶液pH值响应性.结果表明随溶液pH由酸性转变为碱性,PLGA50-b-D2-(PLL9)4显示出了多重胶束化行为,同时不对称的线型-树状分子拓扑结构影响了聚集体的形貌,在酸性pH值下形成以PLGA为核的球形胶束,而在碱性pH值下形成以PLL为核的棒状胶束,并分别伴随着PLGA及PLL链段构象从无规线团向螺旋构象的转变.  相似文献   

10.
锰氧化物是一类重要的且具有广泛应用背景的材料, 控制合成不同形貌和组成的锰氧化物纳米结构将有助于拓宽其应用领域. 本文报道了以Mn3O4为前驱体, 通过水热法控制合成MnO2纳米结构的方法. 用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)等手段对产物进行表征. 在硫酸体系中,当反应温度为80 和180 ℃时, 所得产物分别为γ-MnO2海胆结构和β-MnO2单晶纳米棒. 此外, MnOOH纳米线可以在稀酸溶液中合成. 考察了反应温度、溶液酸度、反应时间对产物结构的影响, 并提出了基于γ-MnO2为中间产物的反应机理. 实验结果表明, 水热体系促进了产物的各向异性生长并最终形成不同形貌和结构的锰氧化物.  相似文献   

11.
Hyperbranched poly(amido amine)s containing vinyl and hydroxyl groups were successfully synthesized via Michael addition polymerization of triacrylamide (TT) and 3-amino-1,2-propanediol (APD) with equal molar ratio in feed. 1H, 13C and HSQC NMR techniques were used to clarify the structure of hyperbranched polymers and polymerization mechanism. The Michael addition reaction of hyperbranched poly(1TT-1APD)s with primary amine-terminated poly(ε-benzyloxycarbonyl-l-lysine)s [PLys(Z)] yielded a star-like hyperbranched polymers with poly(1TT-1APD) core and Plys(Z) shell. The Z groups in PLys(Z) were removed under acidolysis, and thus star-like hyperbranched polymers with hydroxyl groups inside and primary amine groups outside were obtained successfully.  相似文献   

12.
A series of water soluble aliphatic hyperbranched poly(amido amine)s(PAMAMs) with the same or similar chemical structure of poly(amido amine) dendrimer was successfully synthesized from commercially available AB and Cn types of monomers by one-pot polymerization via the couple-monomer methodology(CMM). The AB type monomer used in this paper was methyl acrylate, and Cn monomers were multi-amino compounds such as ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetraamine (TETA). tetraethylenepentaamine (TEPA) and pentaethylenehexamine (PEHA). The reaction mechanism was investigated by means of the mass spectra of the reaction intermediates. Adjusting the feed ratio of AB to Cn. hyperbranched polymers with different terminal groups and properties were obtained. FTIR, NMR, DSC. and TGA were used to characterize the polymers. It was found that the polymers‘ properties such as solubility, thermal behaviour and encapsulation capability varied with changing the feed ratio of AB to Cn. Benzoyl and palmitoyl groups were introduced into these macromolecules by acidylation to form amphiphilic hyperbranched polymers which have a high capability to encapsulate water soluble dyes such as Congo red. It is expected that the hyperbranched PAMAMs can play an important role in the industrial applications, such as coatings, cross-linking and phase-transferring agents because of their versatility and availability.  相似文献   

13.
Novel hyperbranched poly(amido amine)s containing tertiary amines on the backbones and acryl or secondary amines as the surface groups were successfully synthesized via the Michael addition polymerizations of a triacrylamide [1,3,5‐triacryloylhexahydro‐1,3,5‐triazine (TT)] and a difunctional amine [n‐butylamine (BA)] NMR techniques were used to clarify the structures of hyperbranched polymers and polymerization mechanism. The reactivity of the secondary amine formed in situ was much lower than that of the primary amines in BA. When the feed molar ratio was 1:1 TT/BA, the secondary amine formed in situ was almost kept out of the reaction before the BA (AA′) and TT (B3) monomers were consumed, and this led to the formation of A′B2 intermediates containing one secondary amine group and two acryl groups. The self‐polymerization of the A′B2 intermediates produced hyperbranched polymers bearing acryl as surface groups. For the polymerization with the feed molar ratio of 1:2 TT/BA, A′2B intermediates containing one acryl group and two secondary amine groups were accumulated until self‐polymerization started; the self‐polymerization of the intermediates formed hyperbranched polymers with secondary amines as their surface groups. Modifications of surface functional groups were studied to form new hyperbranched polymers. The hyperbranched poly(amido amine)s were amorphous. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6226–6242, 2006  相似文献   

14.
陈皞  贾志峰  颜德岳 《高分子学报》2007,(11):1097-1101
由聚丙二醇二缩水甘油醚和甘油通过质子转移聚合(proton transfer polymerization)一步法制备了端羟基的温敏性超支化聚醚.聚合产物的分子量(Mn)在1.76×104~2.43×104之间,玻璃化转变温度(Tg)在-31.5~-26.7℃之间,热分解温度(Td)在367~376℃之间.通过控制聚丙二醇二缩水甘油醚和甘油的投料比,实现了对温敏性超支化聚醚最低临界溶解温度(LCST)的调节,LCST可控制在28.3~39.6℃之间.  相似文献   

15.
A series of novel, fully aromatic high-molecular-weight poly(amide-ester)s was prepared by the direct polycondensation from terephthalic acid (TPA) and 2,6-naphthalene dicarboxlic acid (NDC) with various aromatic diols and diamines in the presence of diphenyl chlorophosphate (DPCP), LiCl, and pyridine. The structures and thermal properties of these synthesized poly(amide-ester)s were examined by FTIR, wide-angle x-ray diffraction (WAXD), differential scanning calorimetry (DSC), thermal polarized optical microscope, thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA). The effects of the kinds of the aromatic diols and diamines (bisphenyl units, naphthalene, and (un)substituted phenylene structures) on the thermal properties of the synthesized poly(amide-ester)s were investigated in this study. Strong interchain interactions were induced by using a 50:50 molar ratio of the amide groups to the ester groups, and, thus, no LC properties but good thermal stabilities were found in all of the synthesized poly(amide-ester)s containing naphthalene, substituted hydroquinone, or bisphenol segments in this study. However, another series of poly(amide-ester)s with a molar ratio of diamine to diol of 20:80 exhibited excellent mesophase stabilities, with various molar ratio of terephthalic acid (TPA) to 2,6-naphthalene dicarboxlic acid (NDC). © 1996 John Wiley & Sons, Inc.  相似文献   

16.
5.5′,6,6′‐Tetrahydroxy‐3,3,3′,3′‐tetramethyl spirobisindane (TTSBI) was polycondensed with 4,4′‐difluorodiphenylsulfone (DFDPS) in DMSO with K2CO3 as catalyst and azeotopic removal of water. The feed ratio of DFDPS/TTSBI was varied from 1.0/1.0 to 2.0/1.0 at concentrations avoiding gelation. At feed ratios around 1.0/1.0 hyperbranched polymers were a minority and cyclic poly(ether sulfone)s were the predominant reaction products. With increasing feed ratio of DFDPS more and more multicyclic polymers were formed, and at a feed ratio of 1.9/1.0 perfect multicycles free of functional groups were the vast majority of the reaction product. Despite variation of the reaction conditions quantitative conversion was not achieved. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5597–5605, 2007  相似文献   

17.
袁攀  胡苏军  应磊  杨伟 《应用化学》2010,27(3):262-266
用Suzuki缩聚反应合成了以三-(2-间溴苯基吡啶)合铱为核,以聚2,5-二辛氧基苯为枝的超支化电磷光绿光聚合物(PPPIrppy)。 聚合物中当铱配合物摩尔分数大于0.5%时,主体的发射被完全淬灭,电致发光(EL)光谱只有位于520 nm处的绿光发射,表明主客体之间发生了有效的能量转移。 基于铱配合物摩尔分数为1%的聚合物的发光器件(器件结构:ITO/PEDOT:PSS/emissive layer/Ba/Al)在电流密度为40×10-3 A/cm2时,最大电流效率达到2.89 cd/A,器件的最大亮度达到1 689 cd/m2,色坐标为(0.34,0.59)。  相似文献   

18.
Hyperbranched polysiloxane polymers with multivinyl functionality were designed and synthesized through a “one‐step and one‐pot” deactivation enhanced atom transfer polymerization (DE‐ATRP) approach from the copolymerization of polydimethylsiloxane (PDMS) macromonomers and divinylbenzene (DVB). Various feed ratios of siloxane‐based monomer and divinyl monomers were investigated. We showed that even at DVB concentrations as high as 80 mol % in the feed, 65% yield of hyperbranched polymer could be obtained without gelation because the DE‐ATRP suppressed the rapid formation of macronetwork structures. The molecular weight, polydispersity, macromolecular structure of hyperbranched poly(DVB‐co‐PDMS) as well as its viscosity in silicone oil were characterized by GPC‐MALLS, 1H NMR and rheometer. By tracking the relationship between the radius of gyration, elution volume and molecular weight from MALLS analysis, solid evidences of the highly branched and condensed structure of the polymers were obtained. Furthermore, the oil thickening experiments demonstrate that this hyperbranched polymer can act as a well‐controlled viscosity‐modifier for Silicone oils, which potentially will have important application in coating, cosmetic and pharmaceutical products. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

19.
Novel star‐like hyperbranched polymers with amphiphilic arms were synthesized via three steps. Hyperbranched poly(amido amine)s containing secondary amine and hydroxyl groups were successfully synthesized via Michael addition polymerization of triacrylamide (TT) and 3‐amino‐1,2‐propanediol (APD) with feed molar ratio of 1:2. 1H, 13C, and HSQC NMR techniques were used to clarify polymerization mechanism and the structures of the resultant hyperbranched polymers. Methoxyl poly(ethylene oxide) acrylate (A‐MPEO) and carboxylic acid‐terminated poly(ε‐caprolactone) (PCL) were sequentially reacted with secondary amine and hydroxyl group, and the core–shell structures with poly(1TT‐2APD) as core and two distinguishing polymer chains, PEO and PCL, as shell were constructed. The star‐like hyperbranched polymers have different sizes in dimethyl sulfonate, chloroform, and deionized water, which were characterized by DLS and 1H NMR. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1388–1401, 2008  相似文献   

20.
以1,2,4-偏苯三羧酸酐(BTAA)和乙醇胺(EMA)为原料,分别采用"二步法"和"一步法"熔融缩聚制备了端羧基超支化聚酯酰胺(HBPEA).第1步利用官能团非等活性原理,在乙醇溶剂中由BTAA中高活性的酸酐基团与EMA中高活性的氨基反应原位生成含1个羟基和2个羧基的AB_2中间体,蒸除乙醇后,再第2步熔融缩聚得到超支化聚酯酰胺,可避免聚合过程中发生凝胶.为便于工业化应用,还采用BTAA与EMA经"一步"熔融缩聚制备了端羧基超支化聚酯酰胺.分别采用核磁共振(NMR)、乌氏黏度计、示差扫描量热仪(DSC)、热失重分析仪(TGA)以及阿贝折射仪等对2种方法所制备的目标产物化学结构和特性黏度等各项性能进行了表征,结果表明:所得聚酯酰胺具有超支化结构,特性黏数为0.12~0.15 d L/g,支化度为0.64~0.65,在350oC之前未发生热失重,玻璃化转变温度为125~126oC,折射率为1.57~1.58,与聚碳酸酯(PC)相近.因此将其作为加工助剂用于PC塑料体系的加工.超支化聚酯酰胺的加入,不仅能改善PC的加工流动性,同时还能改善制品的机械性能和表面光洁度,且不会引起PC色泽的变化.  相似文献   

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