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1.
Disulfide‐functionalized hyperbranched poly(amido amine)s (HPAMAMs) were synthesized by Michael addition polymerization of N,N'‐cystaminebisacrylamide and 1‐(2‐aminoethyl)piperazine. The novel HPAMAMs displayed bright fluorescence, and the emissions bands cover nearly the whole visible wavelength range. When polymer solutions were excited at 330–385, 460–490, and 510–550 nm, blue, green, and red solutions were observed, respectively. The HPAMAMs are biodegradable and they can be easily cleaved by 2‐mercaptoethanol or glutathione, leading to a decrease in the fluorescence intensity. Studies of applications of the biocompatible and biodegradable HPAMAMs in fluorescence imaging technology and biological science are in progress.

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2.
以4-全氟壬烯氧基苯磺酰氯和2-甲氨基乙醇为主要原料,经酰胺化、酯化和中和反应制备了硫酸2-(N-甲基-4-全氟壬烯氧基苯磺酰胺基)乙酯钠(I),用红外光谱和19F NMR,1H NMR对中间体和产物分子结构进行了表征,借助正交试验法优化了反应条件。酰胺化反应较佳工艺条件:n(4-全氟壬烯氧基苯磺酰氯): n(2-甲氨基乙醇)=1.0 : 2.0,以三乙胺为缚酸剂,在THF溶剂中,室温下搅拌反应3.0 h,收率93.4 %;酯化反应较佳工艺条件:n( N-羟乙基-N-甲基-4-全氟壬烯氧基苯磺酰胺): n(氯磺酸)=1.0 : 2.0,在THF溶剂中,室温下反应0.5 h,收率97.1 %。硫酸2-(N-甲基-4-全氟壬烯氧基苯磺酰胺基)乙酯钠表面活性剂的临界胶束浓度 8.0×10-4mol/L,γcmc 23.1 mN/m (25℃)。  相似文献   

3.
Hyperbranched epoxide‐amine adducts were synthesized by a one‐pot microwave (MW) assisted reaction. 4‐(2,3‐epoxypropyl‐1‐oxy)benzonitrile was hydrogenated using Pd/C under microwave conditions, forming the AB2 monomer 1‐aminomethyl‐4‐(2,3‐epoxypropyl‐1‐oxy)benzene. Depending on the reaction temperature this monomer immediately reacts to give hyperbranched epoxide‐amine adducts. Mass spectrometric investigations proved the formation of a homologous series of oligomers containing up to six repeating units. Due to the complexing properties of the poly(amino alcohol) moieties in the presence of Cu2+ ions, large aggregates were formed.

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4.
贾志峰  陈皞  颜德岳 《化学学报》2005,63(20):1861-1865
由甲基丙烯酸羟丙酯通过自缩合乙烯基氧阴离子聚合(self-condensing vinyl oxyanionic polymerization)制备了端羟基的超支化聚甲基丙烯酸酯. 以氢化钾(KH)和冠醚的复合物为引发剂时, 可以得到高分子量的聚合物. 用1H NMR和13C NMR谱图证实了聚合物的超支化结构. 由于在聚合过程中存在质子转移反应, 引发剂与单体的摩尔比会影响所得聚合物的结构. 超支化聚合物的玻璃化转变温度在58.1~81.4 ℃之间, 且随着引发剂与单体的比例的减小而降低. 当引发剂与单体等摩尔比时, 所得聚合物的支化度为0.49.  相似文献   

5.
一种磺酸聚醚型表面活性剂的制备及动态表面张力   总被引:1,自引:0,他引:1  
通过3-氯-2-羟基丙磺酸钠(NaCHPS)和1-氯-3-丁氧基-2-丙醇(CBP)之间溶液共缩聚,合成了一种新型磺酸聚醚表面活性剂—环氧丙磺酸缩水甘油丁基醚共聚物。采用红外、核磁等测试技术对其结构进行了表征。测定了不同质量浓度、不同结构的磺酸聚醚水溶液的动态表面张力(DST),并用Rosen经验方程对DST进行了分析。结果表明,磺酸聚醚的数均分子量为900~1 600,其溶液浓度越高,DST达到介平衡越快,则DST分析曲线越低;当质量浓度从56.4 mg/L增大到3 611 mg/L时,R_(1/2)值从11.04 mN/(m·min)增大到7 662.5 mN/(m·min);磺酸聚醚的动态表面活性随着磺酸聚醚中CBP含量的增加而增强。  相似文献   

6.
7.
Novel hyperbranched poly(amido amine)s containing tertiary amines in the backbones and acryl as terminal groups were synthesized via the Michael addition polymerizations of trifunctional amines with twofold molar diacrylamide. The hyperbranched structures of these poly(amido amine)s were verified by 13C NMR (INVGATE). The polymerization mechanisms were clarified by following the polymerization process with NMR method, and the results show that the reactivity of secondary amine formed in situ is much lower than that of the secondary amine in 1‐(2‐aminoethyl) piperazine (AEPZ) ring and the primary amine. The secondary amine formed in situ was almost kept out of the reaction before the primary and secondary amines in AEPZ were consumed, leading to the formation of the AB2 intermediate, and the further reaction of the AB2 yielded the hyperbranched polymers. The molecular weights and properties of poly(amindo amine)s obtained were characterized by GPC, DSC, and TGA, respectively. Based on the reaction of active acryl groups in the polymers obtained with glucosamine, hyperbranched polymers containing sugar were formed. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5127–5137, 2005  相似文献   

8.
含氟表面活性剂溶液的动态表面张力研究   总被引:1,自引:0,他引:1  
本文研究了阳离子氟表面活性剂CF3CF2CF2O(CF(CF3)CF2O)2CF(CF3)CONH(CH2)3N+(C2H5)2CH3I-(简写FC-4 )的动态表面性质,利用Krüss K12和MBP动态表面张力仪分别测定了该体系的平衡表面张力和动态表面张力。由平衡表面张力测定结果得到了临界胶束浓度和表面吸附量。利用渐进的Ward and Tordai方程对动态数据进行了分析。结果表明:在吸附的最初阶段符合扩散控制模型,而在吸附的后期,证明了吸附势垒的存在,表明在吸附后期属于混合动力学模型。计算得出25 ℃时,该体系势垒约在25到35 kJ/mol. 由于氟表面活性剂分子间作用力小,表面压是导致吸附势垒的主要原因。  相似文献   

9.
10.
以N-丙烯酰-1,2-乙二胺盐酸盐(ADE)合成为基础,通过ADE的Michael加成反应制备阳离子超支化聚合物聚N-丙烯酰-1,2-乙二胺盐酸盐(HADE),并对其结构进行了表征。研究表明,50℃下,HADE破乳剂(质量浓度为200 mg/L)对含煤油质量分数5%的水包油(O/W)煤油乳液的除油率可高达95.6%,显示了产品在乳液破乳除油方面良好的发展前景。  相似文献   

11.
系列阳离子双子表面活性剂的合成及其表面活性的研究   总被引:10,自引:0,他引:10  
孙玉海  董宏伟  冯玉军  陈志 《化学学报》2006,64(18):1925-1928
合成了一系列新型的阳离子双子表面活性剂二溴化-N,N'-二(二甲基烷基)乙二铵(12-2-m', m'=4, 8, 12, 16), 初步研究了其水溶液的表面活性和电导率性质. 结果表明, 此类表面活性剂的表面活性与所含疏水尾基的碳数密切相关.  相似文献   

12.
The synthesis of a new azobenzene(azo)-containing main-chain crystalline polymer with reactive secondary amino groups in its backbone and photodeformation behaviors of its supramolecular hydrogen-bonded fibers are described. This main-chain azo polymer(namely Azo-MP6) was prepared via first the synthesis of a diacrylate-type azo monomer and its subsequent Michael addition copolymerization with trans-1,4-cyclohexanediamine under a mild reaction condition. Azo-MP6 was found to have a linear main-chain chemical structure instead of a branched one, as verified by comparing its ~1H-NMR spectrum with that of the azo polymer prepared via the polymer analogous reaction of AzoMP6 with acetic anhydride. The thermal stability, phase transition behavior, and photoresponsivity of Azo-MP6 were characterized with TGA,DSC, POM, XRD, and UV-Vis spectroscopy. The experimental results revealed that it had good thermal stability, low glass transition temperature,broad crystalline phase temperature range, and highly reversible photoresponsivity. Physically crosslinked supramolecular hydrogen-bonded fibers with good mechanical properties and a high alignment order of azo mesogens were readily fabricated from Azo-MP6 by using the simple melt spinning method, and they could show "reversible" photoinduced bending under the same UV light irradiation and good anti-fatigue properties.  相似文献   

13.
以季戊四醇为"核分子"超支化聚酯-酰胺的合成及表征   总被引:4,自引:0,他引:4  
以二异丙醇胺(DIPA)与六氢苯酐(HHPA)为原料合成了一种端基带有一个羧基、两个羟基的AB2型单体。用季戊四醇(PETL)作为“核分子”,按一定的摩尔配比与AB2型单体反应,分别得到两种不同的超支化聚酯-酰胺(1GHP、2G—HP)。并采用红外光谱(IR)、凝胶渗透色谱法(GPC)、粘度法等方法对其结构进行了表征。结果表明:1GHP、2G—HP的多分散性指数分别为1.47和2.17,呈现很窄的分子量分布。两种分子的粘度与浓度的关系服从Einstein粘度方程,具有紧凑的球形分子结构。  相似文献   

14.
李杰  柴云  张普玉 《化学研究》2010,21(4):58-61
采用阴离子开环聚合法合成了两亲性嵌段共聚物PLA-PEG-PLA.用FT-IR,1H NMR和GPC等手段对嵌段共聚物的结构组成进行了表征.两亲性嵌段共聚物在离子液体1-丁基-3-甲基咪唑六氟磷酸盐中能自组装成胶束,用透射电子显微镜观察了聚合物在离子液体中形成胶束的纳米结构.当疏水链长固定时,胶束的自组装形状主要依赖于亲水链的长度.两亲性共聚物在离子液体中可自组装成可控制结构的纳米胶束,这种纳米结构胶束在很多领域具有广泛的应用前景.  相似文献   

15.
Poly(methyl acrylate)-b-poly(N-vinyl pyrrolidone/maleic anhydride/styrene) (PMA-b-P (NVP/MAH/St)) quaternary amphiphilic block copolymer prepared by reversible addition-fragmentation chain transfer (RAFT) was used to improve the anti-hydrolysis and dispersion properties of aluminum nitride (AIN) powders that were modified by copolymers. Its structure was characterized by Fourier transform infrared spectroscopy (FT-IR) and Hydrogen nuclear magnetic spectroscopy (1H-NMR). The results demonstrate that the molecular weight distribution of the quaternary amphiphilic block copolymers is 1.35–1.60, which is characteristic of controlled molecular weight and narrow molecular weight distribution. Through charge transfer complexes, NVP/MAH/St produces a regular alternating arrangement structure. After being treated with micro-crosslinking, AlN powder modified by copolymer PMA-b-P(NVP/MAH/St) exhibits outstanding resistance to hydrolysis and can be stabilized in hot water at 50 °C for more than 14 h, and the agglomeration of powder particles was improved remarkably.  相似文献   

16.
Various water‐soluble hyperbranched poly(ester amine)s were synthesized by the direct polyaddition of diamines to diacrylates in the absence of a catalyst. Each diamine contained a secondary amino group and a primary amino group such as 1‐(2‐aminoethyl)piperazine, N‐methyl‐1,3‐propanediamine, or N‐ethylethylenediamine. When the ratio of diacrylate to diamine was 1/1, no gelation was observed throughout the polymerization. When the ratio of diacrylate to diamine was 3/2, no crosslinking occurred in the diluted solution, whereas an insoluble network formed in the concentrated solution. Fourier transform infrared and mass spectrometry were used to investigate the reaction procedure. The secondary amino group of diamine reacted faster with the vinyl group of diacrylate; this resulted in the formation of the intermediate with an acrylate group and two active hydrogen atoms attached to a nitrogen atom. Further self‐polyaddition of the intermediate, a kind of AB2‐type monomer, gave the hyperbranched poly(ester amine). © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2340–2349, 2002  相似文献   

17.
孔立智  乔华明  蒋必彪 《化学学报》2011,69(15):1817-1823
合成了超支化聚苯乙烯-线型聚苯乙烯-超支化聚甲基丙烯酸甲酯三嵌段聚合物(HPS-b-LPS-b-HPMMA). 首先分别合成了带有炔基和溴的三硫代碳酸酯(ATC和BTC), 然后通过苯乙烯(St)的可逆加成-断裂链转移(RAFT)聚合, 制得端炔基和端基溴的线型聚苯乙烯大分子RAFT试剂, 然后将大分子RAFT试剂的溴末端转化为叠氮末端. 接着在大分子RAFT试剂存在情况下, 通过自缩合原子转移自由基共聚合(SCATRCP)分别制得端炔基超支化聚苯乙烯-线型聚苯乙烯(HPS-b-LPS)和端叠氮基超支化聚甲基丙烯酸甲酯-线型聚苯乙烯(HPMMA-b-LPS)两嵌段聚合物. 最后将两种两嵌段聚合物通过点击(click)反应偶合, 得到不对称的超支化-线型-超支化三嵌段聚合物HPS-b-LPS-b-HPMMA. 核磁共振氢谱(1H NMR)、凝胶渗透色谱(GPC)结果表明, 所得产物分子量可控, 得到了预期结构的聚合物.  相似文献   

18.
采用溶液聚合的方法合成聚马来酸酐,考察不同聚合条件对聚马来酸酐产率的影响。将所合成的聚马来酸酐与十八醇、十六醇和十四醇进行酯化反应合成了三种两亲性的大分子表面改性荆聚马来酸酐十八醇酯(PMAO)、聚马来酸酐十六醇酯(PMAH)和聚马来酸酐十四醇酯(PMAT)。对这三种聚马来酸酐高级醇酯/聚乙烯共混体系的表面亲水性进行了研究,采用全反射红外光谱对聚马来酸酐高级醇酯共混体系薄膜进行表征,发现聚马来酸酐高级醇酯可以在聚乙烯薄膜表面富集,接触角测量表明聚马来酸酐高级醇酯的加入可以有效降低聚乙烯薄膜的水接触角。  相似文献   

19.
A novel, pH-responsive supramolecular graft copolymeric micelle, composed of dextran and poly (oleic acid), has been synthesized through reversible addition fragmentation chain transfer polymerization with controlled Mn and narrow polydispersity. The structural properties of the copolymer have been studied using FTIR and 1H NMR spectral analyses. Critical micelle concentration (CMC) has been determined fluorometrically and conductometrically. The copolymer shows pH responsive micellar stability, which has been confirmed using DLS study. Dextran-g-OA copolymer demonstrates spherical morphology at CMC, while rod-like assembly has been evidenced beyond CMC that is probably because of the structural alteration of copolymeric chains at higher copolymer concentration. Dextran-g-OA is noncytotoxic toward MG-63 cells. As the self-assemble nature of copolymer micelle promotes the oral administration of hydrophobic drugs, nifedipine (NFD, a hydrophobic drug) has been used as model drug that has been encapsulated substantially into the core of the micelle. The copolymer releases the loaded NFD at a much slower rate in simulated gastric fluid (pH 1.2) and relatively faster in simulated intestinal fluid (pH 7.4) with a cumulative release of ~95% within 24 h, suggesting an ideal candidate as nifedipine carrier. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 2354–2363  相似文献   

20.
The equilibrium and dynamic surface tension (DST) of the novel cationic surfactant, 3-(p-nonylphenoxy)-2-hydroxylpropyl trimethyl ammonium bromide, abbreviated as RTAB, were studied. The effect of sodium halide such as NaCl, NaBr and NaI on the DST behavior of the RTAB solution below its CMC was studied in detail. Due to the preferential adsorption, the effect of hydration and salting out, the ability to reduce the DST values at the same concentration was in the order of NaI〉NaBr〉NaCl. Attributed to its high surface activity, the equilibrium time of the DST of the surfactant solution was insensitive to the ionic strength.  相似文献   

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