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两亲嵌段共聚物可以在水溶液中自组装形成亲水性链段为外壳、疏水性链段为内核的胶束,这种胶束能够用作药物载体而引起人们极大的关注。本文综述了两亲嵌段共聚物胶束用作医用材料的研究进展,主要内容包括医用两亲嵌段共聚物的种类,胶束化,以及用作诊断试剂载体、药物缓释载体、靶向载体等。两亲嵌段共聚物胶束用作磁共振造影剂载体有利于肿瘤的诊断,用作药物缓释载体可以有效增溶难溶性抗肿瘤药物,延长药物在体内的血液循环时间。此外,通过对胶束表面进行修饰或者施加外场,还可以实现靶向功能。因此,两亲嵌段共聚物胶束在医用材料领域有着广阔的发展前景。 相似文献
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The novel benzoxazine monomer containing phosphorus has been synthesized based on multifunctional amine route from bis(4-aminophenyl)phenylphosphate,p-cresol and formaldehyde.Subsequently,the benzoxazine monomer was thermo-cured into polybenzoxazine containing phosphorus.The chemical structures were identified by nuclear magnetic resonance(NMR),Fourier transform infrared spectroscopy(FT-IR).The curing reaction was monitored by differential scanning calorimetry(DSC) and FT-IR.The thermal and flame-retardant properties of obtained polybenzoxazine were evaluated by dynamic mechanical thermal analysis(DMA),thermal gravimetric analysis(TGA) and oxygen index meter, respectively.The results show that the novel polybenzoxazine has high limiting oxygen index(38.1) and glass transition temperature(232℃). 相似文献
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针对丙烯酸酯大单体在合成过程中常带有颜色,以及由其制备的液态光学透明胶的UV固化膜易黄变的问题,本文报道了一条新的大单体合成路线:首先以端羟基聚丁二烯(HTPB)、萘钾、丙烯酰氯(AC)为原料,通过一锅法合成了一种无色透明的聚丁二烯丙烯酸酯大单体(PBAM);然后将PBAM与丙烯酸酯活性稀释单体、光引发剂混合,制备了液态光学透明胶;最后通过UV固化制备了一系列无色透明的薄膜。利用GPC、1H-NMR、FTIR等手段对PBAM进行了表征;进一步研究了液态光学透明胶UV固化膜的光学性能、耐黄变性能、耐低温性能等。结果表明:基于新路线合成的PBAM呈现无色透明,液态光学透明胶的UV固化膜展现出优良的光学性能和耐黄变性能,固化膜透光率高达98%;经紫外线加速老化264h后,色差(ΔE)≤1.5;此外,该固化膜还具有优良的耐低温性能,玻璃化转变温度为-30℃。 相似文献
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壳聚糖作为药物缓释载体的研究进展 总被引:2,自引:0,他引:2
壳聚糖作为药物缓释载体在减少给药次数,降低药物毒副作用,提高药物疗效等方面具有重要作用。本文综述了壳聚糖作为药物缓释载体的研究进展,主要包括壳聚糖纳米粒子、微球、片、膜和凝胶等的制备和缓释特性,并对其发展趋势进行了展望。 相似文献
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本文采用原子转移自由基聚合方法合成了聚丙烯酸叔丁酯-聚丙烯腈嵌段共聚物(PtBA-b-PAN), 酸解得到聚丙烯酸-聚丙烯腈两亲嵌段共聚物(PAA-b-PAN). 随后, PAA-b-PAN嵌段共聚物在水溶液中自组装形成以PAA为壳, PAN为核的胶束. 用此胶束为模板, 加入FeCl3溶液后得到了壳层负载Fe3+的聚合物纳米粒子, 经230 ℃空气中预氧化, 600 ℃氮气氛煅烧, 得到了核壳结构的, 具有磁性的碳纳米粒子. 用1H NMR, IR, GPC, TGA, TEM, XRD, AGM等技术对嵌段共聚物及纳米粒子进行了表征, 结果表明纳米粒子的壳层含γ-Fe2O3, Fe2.5C混合物, 核含碳, 直径为35 ± 5 nm, 饱和磁化强度为2.16 emu/g. 在分离、吸波和传感器等方面具有潜在的应用前景. 相似文献
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Synthesis of hydroxyl-terminated polybutadiene possessing high content of 1,4-units via anionic polymerization 总被引:2,自引:0,他引:2
<正>The hydroxyl-terminated polybutadiene(HTPB) possessing high content of 1,4-units was synthesized by anionic polymerization of butadiene,using alkyllithium containing silicon-protected hydroxyl group as initiator and cyclohexane as solvent.The polymers were characterized by GPC,IR and ~1H-NMR.The mechanical properties of cured films were also evaluated.The results show that the content of 1,4-units for HTPBs made by anionic polymerization reaches up to 90%.The molecular weight distribution is very narrow(≤1.05).The functionality of hydroxyl groups approaches 2.Compared with free radical HTPB,the elongation at break of anionic HTPB films increased by 70%,while the tensile strength remained nearly unchanged.This new HTPB can be very useful in solid propellant. 相似文献