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研究了以丙烯酸甲酯、己二胺、对苯二酚为原料,采用发散法合成新型端胺基聚酰胺-胺树枝状大分子时,反应条件——温度、反应时间、催化剂对合成产物的结构的影响。利用该树枝状大分子的活性点分布均匀的特点,通过设计和控制树枝状大分子模板剂来控制纳米粒子材料的形状。 相似文献
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以乙二胺和丙烯酸甲酯为原料,采用扩散法合成了不同端基类型不同代数的聚酰胺-胺(PAMAM)树形高分子,并用红外光谱进行表征;以G5.0-NH2 PAMAM树形高分子为模板,以二甲基亚砜为溶剂,在常温下制备了稳定的PAMAM树形高分子包覆的CdSe@CdS核壳结构量子点,并用紫外-可见吸收光谱和荧光发射光谱进行表征。结果表明,适当厚度CdS的包覆修饰可以有效提高CdSe量子点的发光性能;与单一组分的CdSe量子点相比,CdSe@CdS核壳结构量子点的相对荧光强度最大提高约123 %。 相似文献
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两性聚酰胺-胺树状聚合物的合成及絮凝性能 总被引:4,自引:0,他引:4
用Michael加成反应对G4.0聚酰胺-胺(PAMAM)树状聚合物分子进行了表面修饰改性。分别以丙烯酰氧基乙基三甲基氯化铵(DAC)、丙烯酸钠(SAA)、2-丙烯酰胺-2-甲基丙磺酸(AMPS)为端基改性剂,在N2气氛下50℃甲醇溶液中,反应投料比n(PAMAM)∶n(DAC)∶n(SAA或AMPS)=1∶16∶16时,反应96 h,合成出了两性聚酰胺-胺树状聚合物。絮凝性能实验结果表明,合成产物具有一定的絮凝性能,且与聚丙烯酰胺复配效果更好,最佳絮凝效果条件为:m(G4.0/DAC/AMPS)∶m(PAM)=1∶4;投药量16 mg/L;絮凝沉降时间20 min;pH=8~9。 相似文献
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聚氧乙烯链封端的聚酰胺-胺树状聚合物的性质与应用 总被引:2,自引:0,他引:2
研究了聚氧乙烯链封端的非离子型聚酰胺-胺树状聚合物的热稳定性以及在造纸助留和催化剂载体上的应用。结果表明,该类树状聚合物具有较好的热稳定性,温度低于300℃无明显热分解行为,最大的热分解温度均为400℃。助留性能测试表明,M4.0G与P44复配双元助留体系(摩尔比1∶23.22),造纸助留率为89.2%,比空白造纸助留率分别提高了18.3%。纸样的物理机械特性:撕裂指数、撕裂强度、耐破指数、耐破强度和抗张指数比空白纸样分别提高了8.6%、1.5%、35.5%、29.6%和4.3%。TEM测试表明:以聚氧乙烯大单体(PEO-A)链封端的聚酰胺-胺树状聚合物样品封装的钯金属纳米粒子单分散性较好,粒径分布在0.75~2.4nm。 相似文献
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采用不同比例G3.5酯端基类型的聚酰胺胺(PAMAM)树形高分子氯仿溶液与聚(3-羟基丁酸酯-co-3-羟基戊酸酯)(PHBV)树脂氯仿溶液进行共混并流延成膜,采用差示扫描量热分析、偏光显微镜以及拉伸和直角撕裂等方式对制备的PHBV/PAMAM复合膜进行表征。结果表明,随着PAMAM树形高分子的加入,PHBV/PAMAM复合膜的玻璃化转变温度(Tg)越来越明显,初步表明其韧性增强; G3.5 PAMAM树形高分子的加入,可使PHBV的结晶度由61.70 %先下降至24.02 %,并逐渐下降,最后至结晶消失; PAMAM树形高分子的加入可使PHBV的直角撕裂强度大幅度提高,最高可由8.90 kN/m提高到22.10 kN/m;当PAMAM树形高分子含量为2.0份时,增韧效果最好。 相似文献
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聚氧乙烯链封端的聚酰胺-胺树状聚合物的合成与表征 总被引:1,自引:0,他引:1
采用酰氯法,用丙烯酰氯和不同相对分子质量的聚乙二醇为原料,制备出一系列具有丙烯酰端基的聚氧乙烯大单体(PEO-A)。实验证明,较佳的原料摩尔比n(PEG)∶n(CH2CHCOCl)∶n〔(CH3CH2)3N〕=2∶1∶1。然后以聚氧乙烯大单体为端基改性剂,在氮气保护下50℃四氢呋喃溶液中分别与G1.0~G4.0聚酰胺-胺树状聚合物进行Michael加成反应96h,合成出了聚氧乙烯(PEO)链封端的非离子型聚酰胺-胺树状聚合物,并用傅立叶变换红外光谱(FTIR)、核磁共振波谱(1HNMR,13CNMR)对其组成和结构进行了表征。 相似文献
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聚酰胺-胺树枝状高分子及其研究进展 总被引:4,自引:0,他引:4
介绍聚酰胺胺树枝状高分子的结构和性能,聚酰胺胺的特殊结构决定了其独特的物化性质。同时,对其合成方法、及其经改性后的树枝状高分子在生物医药、表面活性剂、催化剂、污水处理和膜材料等方面的应用研究进展进行了综述。 相似文献
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Dr. Grégory Coué Dr. Iris Hermanns Dr. Ronald E. Unger Prof. C. James Kirkpatrick Prof. Johan F. J. Engbersen 《ChemMedChem》2013,8(11):1787-1794
A poly(amidoamine) with disulfide linkages in the main chain and 4‐hydroxybutyl and ω‐carboxy‐PEG groups (9:1 ratio) as side chains was prepared by Michael addition polymerization of cystamine bisacrylamide with 4‐hydroxybutylamine and ω‐carboxy‐PEG‐amine. To develop therapeutic protein formulations for improved delivery of antigen via the intranasal route, nanoparticles were prepared from this polymer by self‐assembly with p24 or ovalbumin as the model proteins and CpG as the adjuvant. The nanoparticles incorporated the antigens and adjuvant from the feed solution with high efficiency (~90 %) and have sizes of 112 and 169 nm, respectively, with low positive surface charge (~+2 mV). Formulations of the nanoparticles were shown to be nontoxic and stable for at least 10 days at room temperature. Their capacity to pass through epithelial and endothelial cell layers was evaluated in vitro by using a respiratory mucosa‐like barrier model in which monolayers of NCI H441 respiratory epithelial cells and ISO‐HAS‐1 endothelial cells were co‐cultured on both sides of a transwell filter membrane. It was shown that p24 incorporated in the nanoparticles was transported with >140 % greater efficiency through the two contact‐inhibited layers than p24 in its free form, whereas incorporation of ovalbumin in the nanoparticles leads to a 40 % decrease in transport efficiency relative to the free antigen. 相似文献
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Longyin Qiao Wanjing Zhang Libo Xu Fu Han Yawen Zhou Baocai Xu 《Journal of surfactants and detergents》2020,23(2):263-271
A series of Gemini surfactants N,N″-dialkyl-N,N′,N″-tripropionate diethylenetriamine (referred as DTPDT-n, where n is the length of the hydrocarbon chain, n = 10, 12, 14) were synthesized, which have three carboxylic head-groups and two hydrophobic alkane chains. The products were characterized by means of nuclear magnetic resonance and mass spectrometry. The physicochemical properties of DTPDT-n surfactants with different hydrocarbon chain lengths were studied such as isoelectric point, surface activities, emulsifying properties, and foam properties. It is showed that these compounds exhibit pH-dependent protonation-deprotonation behavior. The isoelectric points of DTPDT-n surfactants are between 3.40 and 10.90. The critical micellar concentration (cmc) of all three surfactants are lower than the corresponding monomeric surfactants (single head group, single-chain), especially DTPDT-14, whose cmc can reach 2.29 × 10−5 mol/L. With an increase in the length of the alkyl chain, the solubility of the surfactants decreases and the surface tension of the three surfactants at cmc increases. In consideration of pH, all of three surfactants appear better emulsifying capacity and foaming property under weak alkaline conditions. DTPDT-14 has the best performance of emulsifying capacity among the three surfactants. DTPDT-10 has excellent foaming ability and foam stability. 相似文献
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端羧基超支化聚合物-铝无铬鞣剂的制备及应用 总被引:1,自引:0,他引:1
根据超支化聚合物官能团度大,反应活性高的特点,利用端羧基超支化聚合物(HPAE-C)的末端羧基与Al3+络合,制备一种新型的无铬鞣剂(HPC-Al),通过单因素实验考察了反应条件对成革收缩温度的影响,确定了最佳合成条件:m(HPAE-C)∶m〔Al2(SO4)3〕=2∶1,反应温度30℃,pH=3,反应时间3 h。采用IR、XRD对产品分子结构进行表征,并采用热重分析仪测试了产品的热性能,HPC-Al的热分解温度为243℃。将产品应用于皮革鞣制中,其单独鞣革收缩温度为76.6℃,铬复鞣后收缩温度大于95℃,且物理力学性能明显提高。 相似文献
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采用单因素和正交实验方法,研究了羧甲基淀粉取代度与一氯乙酸用量、反应时间、反应温度、乙醇用量、氢氧化钠用量之间的关系,找出了取得最大取代度的优化反应条件,并对产物和原料淀粉进行了IR谱图的表征. 相似文献