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1.
以N,N-二羟乙基-3-胺基丙酸甲酯单体和季戊四醇(核)为原料,采用“准一步法”合成了具有端羟基的超支化聚胺酯(HPAE)。采用凝胶色谱、红外光谱、核磁共振和热重分析等对其进行了结构表征及性能探究。再以HPAE封装稀土粒子钕(Nd),制备出Nd复合纳米粒子,透射电镜(TEM)分析结果表明:随着HPAE代数增大,Nd纳米颗粒粒径越均匀,分散度越好。  相似文献   

2.
设计并通过原子转移自由基聚合方法 (ATRP)合成了核壳型多羟基多臂星状超支化聚合物刷 .以 2 溴异丁基酰溴封端的超支化聚 (3 乙基 3 羟甲基氧杂环丁烷 ) (HP Br)作为大分子引发剂 ,采用Cu(I)Br和N ,N ,N′ ,N′ ,N″ 五甲基二乙基三胺 (PMDETA)催化体系 ,在丁酮与丙醇的混和溶液中 ,通过甲基丙烯酸羟乙酯(HEMA)的ATRP溶液聚合 ,得到了一系列含有大量羟基的多臂星状超支化聚合物刷 (HP g PHEMA) ,并考察了其羟基的活性 ,发现羟基还可以与苯甲酰氯发生反应 .产物的结构和热性能用1 H NMR、FTIR、GPC、TGA、DSC等进行了表征和测试 .  相似文献   

3.
利用二乙醇胺和丙烯酸甲酯合成的N,N-二羟乙基-3-胺基丙酸甲酯作为AB2型单体,以纳米SiO_2为核,通过其表面羟基与单体的反应,制得SiO_2接枝超支化聚酯的纳米粒子(SiO_2-HBP);再利用超支化端羟基与α-己内酯进行开环反应,合成了含柔性长链的二氧化硅-长链超支化聚酯杂化物(SiO_2-HBP-L);然后将杂化物与丁苯橡胶共混,制备了SiO_2-HBP-L/SBR纳米复合材料.FTIR、XPS和TGA测试证实改性后纳米SiO_2表面接枝了含长链超支化聚酯.SEM测试结果表明,相对于未改性的纳米SiO_2,SiO_2-HBP-L在乙醇和橡胶基体中分散性较好,且改性后纳米SiO_2与复合材料的相容性明显提高.硫化性能测试表明,SiO_2-HBP-L能大大缩短胶料的正硫化时间,增大总交联密度;同时SiO_2-HBP-L/SBR纳米复合材料的力学性能和耐磨性能有较大的提高,很好地实现了补强.  相似文献   

4.
近年来,颜德岳等基于A2型单体二丙烯酸酯及BB2′型单体二胺化合物合成了多种端胺基超支化聚(酯-胺),并对反应机理及聚合物结构进行了系统研究[1,2],结果表明,由于B与B′活性差异,反应首先生成AB2′型和B4′型中间体,进一步聚合得到可溶性产物.我们基于A3型单体三丙烯酸酯与B2型单体二胺化合物合成了端丙烯酸酯基超支化聚(酯-胺)[3,4].在这些体系中,由于官能团反应活性高,难以控制反应程度.另外,由于超支化聚合物不能直接用作结构材料,其在涂料、粘合剂等领域的应用多基于末端官能团的固化反应[5].但通常由于官能团在分子表面密集分布,部…  相似文献   

5.
设计并通过原子转移自由基聚合方法 (ATRP)合成了核壳型具有梯度极性的多羟基多臂星状聚合物刷 .端羟基超支化聚 (3 乙基 3 羟甲基氧杂环丁烷 )与 2 溴 异丁基酰溴反应制得大分子引发剂 (HP Br) ,以Cu(I)Br和N ,N ,N′ ,N′ ,N″ 五甲基二乙基三胺 (PMDETA)为催化体系 ,进行甲基丙烯酸甲酯 (MMA)的ATRP反应 ,得到以甲基丙烯酸甲酯为臂的多臂星状超支化聚合物 (HP g PMMA) .又以HP g PMMA为引发剂 ,进行甲基丙烯酸羟乙酯 (HEMA)的ATRP聚合 ,得到核壳型具有梯度极性的多羟基多臂星状超支化聚合物 (HP g PMMA b PHEMA) ,继续将其羟基官能团溴代化 (与 2 溴 异丁基酰溴反应 ) ,引发HEMA的ATRP溶液聚合 ,得到了多臂星状超支化聚合物刷 .产物的结构用1 H NMR、FTIR、GPC等进行了表征和测试 .  相似文献   

6.
超支化聚(酯-酰胺)的合成与流变改性研究   总被引:10,自引:0,他引:10  
近十几年来 ,超支化聚合物因具有独特的结构和特殊的性能而受到普遍关注[1] .超支化聚合物具有低的熔体粘度 ,与线性聚合物共混可显著改善其加工流变性 ,具有商业应用潜力 .关于超支化聚合物在流变改性方面的应用已有文献报道[2~ 6] ,但目前文献中的大多数单体合成较繁琐且收率不高 ,这已成为制约超支化聚合物应用的瓶颈 ,如何以简便的途径合成超支化聚合物已成为当前研究的重点 .本文设计一条新的合成路线 ,即以 1 ,2 ,4 苯三酸酐、乙醇胺及乙酸酐为原料 ,以高的收率得到了单体N ( 2 乙酰氧基乙基 ) N ( 2′ ,4′ 二羧基苯甲酰基 )胺 (…  相似文献   

7.
N-三羟甲基甲基氨基乙磺酸(TES)的胺基与异佛尔酮二异氰酸酯(IPDI)环上活性较高的NCO在低温15℃下发生选择性反应,生成AB3型单体.随后提高反应温度(70~90℃),使AB3型单体原位聚合,一锅法合成出含磺酸基超支化聚氨酯.随着聚合温度的提高,超支化聚氨酯的支化度、分子量及分子量分布系数变大.90℃时,聚合产物的Mn为22410,支化度达到0.87.以此含磺酸基超支化聚氨酯为基础制得的聚合物电解质膜具有良好的耐热性、机械强度,其锂盐室温(约25℃)的离子电导率为3.1×10-5S/cm,100℃达到1.4×10-3 S/cm.  相似文献   

8.
通过硅氢加成反应, 以ABx型功能化β-环糊精大单体为原料, 采用一步法合成出新型超支化聚(β-环糊精)高分子. ABx大单体由单取代对甲苯磺酰化β-CD依次与烯丙基胺、1,1,3,3-四甲基二硅氧烷(含氢双封头)及丙烯酰氯反应得到. 采用1H NMR, 13C NMR, 29Si NMR和飞行时间质谱对ABx大单体及其聚合物的结构进行了表征. 利用凝胶渗透色谱/多角度激光光散射(SEC/MALLS)联用仪得到了超支化聚(β-环糊精)的分子量、分子量分布及本体黏度.  相似文献   

9.
AB_3型超支化聚(酰胺-酯)的合成及缩聚动力学研究   总被引:6,自引:0,他引:6  
采用丁二酸酐、三羟甲基氨基甲烷为主要原料 ,在冰水浴条件下 ,合成AB3型单体 ,然后进行熔融缩聚制得超支化聚 (酰胺 酯 ) ,没有出现凝胶现象 .采用Fourier变换红外谱仪 (FTIR)、粘度测试、端基分析等方法对其结构、特性粘数进行了表征 .同时对AB3型超支化聚 (酰胺 酯 )的缩聚反应动力学进行了研究 ,得出了130℃、14 0℃和 15 0℃时的缩聚反应速率常数 ,并进一步得出了缩聚反应活化能 .实验结果证明缩聚过程为自催化过程 ,且为三级反应  相似文献   

10.
以四重氢键结合的超支化聚合物及其涂层材料   总被引:3,自引:1,他引:2  
合成了以Upy(2-ureido-4[1H]-pyrimidone)封端的超支化聚合物并研究其涂层材料性能.首先在哌嗪与三羟甲基丙烷三丙烯酸酯摩尔比2.25∶1条件下,合成了端仲胺基超支化聚(酯-胺)(HPEA),进而在仲胺基/异氰酸酯基官能团比1∶0.3、1∶0.4和1∶0.5下,通过HPEA与单异氰酸酯基甲基异胞嘧啶反应,合成了一系列带有Upy基元的改性超支化聚合物.由于Upy基元间形成了自识别四重氢键,改性聚合物比HPEA具有更高的玻璃化转变温度和热分解温度,并且改性聚合物涂层具有优良的力学性能,这表明分子间强氢键相互作用可有效改善超支化聚合物的性能.  相似文献   

11.
超支化聚(胺酯)的合成及其光固化性能研究   总被引:27,自引:1,他引:27  
采用甲基丙烯酸酐直接改性和先以丁二酸酐或邻苯二甲酸酐酯化再以甲基丙烯酸缩水甘油酯改性所得到的甲基丙烯酸酯化超支化聚 (胺 酯 )齐聚物在光引发剂存在时紫外光辐照下发生快速聚合反应 ;反应速率和双键转化率随超支化分子的结构不同而变化 ;高度交联的涂膜具有较好的热学性能  相似文献   

12.
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   

13.
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   

14.
The monomer 2,6,12-triaminotriptycene was synthesized and the structure was confirmed by IR and 1H NMR spectra. Hyperbranched polyimides modified with different terminal groups were obtained from precursors, anhydride- and aminoterminated hyperbranched poly(amic acid)s from polymerization of A2 + B3 system. From gel permeation chromatograrn (GPC) characterization, representative products had high molecular weight. All polymers had good solubility in CHCl3, DMF and tetrahydrofuran (THF), and performed no detective Tgs in the range of 50-300 ℃ and high Tds above 455 ℃ when 5% weight loss.  相似文献   

15.
端丙烯酸酯基超支化聚(酯-胺)的结构分析及光固化   总被引:2,自引:1,他引:1  
近年来 ,具有树枝状结构的超支化聚合物因其独特的物理化学性质而得到广泛关注[1,2 ] .超支化聚合物主要采用 3种途径合成 ,( 1 )ABn(n >2 )型及潜ABn 型单体的聚合 ;( 2 )由A2 与Bn 型单体直接聚合 ;( 3)先由特定的单体对原位形成ABn型中间体后再聚合 .其中后两种方法可直接采用商业化原料 ,因此更具有实用价值 .目前 ,基于途径 ( 2 )已合成出超支化聚酰胺[3 ] 、聚醚[4] 、聚酰亚胺[5] 和共轭聚合物[6] 等 ,但该途径容易生成凝胶化产物 ,通过控制反应物浓度、在凝胶点之前停止反应等 ,可得到溶解型超支化产物 .由于超支化聚合物具有低…  相似文献   

16.
In this research, we developed a novel and facile strategy to prepare aliphatic tertiary amine chromophore hyperbranched poly(amino ether ester)s with pH and thermo responsiveness via phosphazene base (t-BuP2) catalyzed oxa-Michael addition polymerization of triethanolamine with ethylene glycol diacrylate at room temperature. UV–vis and fluorescence analyses results showed that the tertiary amine at branching point for hyperbranched poly(amino ether ester)s is very important to retain strong blue fluorescence of tertiary amine chromophore. Moreover, the hyperbranched poly(amino ether ester)s exhibit an aggregation caused quenching (ACQ) fluorescence, solvent induced red-shifted emission, molecular weight, and temperature dependent emission characters. More interestingly, the hyperbranched poly(amino ether ester)s show extreme acid induced quenching fluorescence phenomenon, and also display good water solubility, specific recognition of Fe3+ ion, low cytotoxicity, and bright cell imaging, which could serve as a microenvironment-responding fluorescent probe for application in chemical sensing, cell imaging, drug delivery, or disease diagnostics. This research provides a versatile method for the preparation of stimuli-responsive aliphatic tertiary amine chromophore polymers, and supplies ideas for researchers to explore other unconventional fluorescent polymers for application.  相似文献   

17.
A novel hyperbranched poly(phenylene oxide) (HPPO) with phenolic terminal groups was prepared from 4-bromo-4',4"-dihydroxytriphenylmethane as AB2 monomer in dimethylsulfoxide (DMSO) via a modified Ullmann reaction. The molecular weight and polydispersity (PD) of the resulting polymers increased with increasing reaction time. In the presence of core molecules (bisphenol A and 1,3,5-trihydroxybenzene), which have the similar molecular backbones to the reactive monomer, the molecular weight could be controlled by varying the core-to-monomer ratio. Incorporation of a very small amount of core molecules could lead to a higher molecular weight as compared with that without the addition of core molecules. However, when the core content reached certain extent, the molecular weight would decrease with the further increase in the core content. A new similar behavior of control over the PD was also obtained. The resulting polymers were characterized by ^1H-NMR, ^13C-NMR, FT-IR, and GPC.  相似文献   

18.
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   

19.
SYNTHESIS OF AN EPOXY-TERMINATED HYPERBRANCHED AROMATIC POLYESTER   总被引:1,自引:0,他引:1  
An epoxy-terminated hyperbranched aromatic polyester (P3) was synthesized from a hyperbranched aromaticpolyester containing carboxylic acid end groups (P1), which was derived from the condensation polymerization of the AB_2monomer, 5-acetoxyisophthalic acid. Polymer P1 was converted into the polymeric acid chloride by reaction with thionylchloride. The acid chloride was reacted with ethanol and glycidol to form a poly(ethyl ester) (P2) and an epoxy terminatedmaterial (P3), respectively. The reaction conditions in each step of these processes had to be controlled very carefully toavoid unwanted cross-linking reactions. The characterization of products and intermediates, including molecular weightdistributions and thermal properties, are reported.  相似文献   

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