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1.
敏感性高分子功能膜的研究进展   总被引:6,自引:0,他引:6  
某些高分子凝胶膜、膜表面或微孔内接枝改性膜、液晶膜具有化学阀的功能,其膜的通透性随外界环境条件变化而改变。详细介绍了PH、温度、电场等外界环境条件变化对此三类膜的敏感性及通透性的影响,以及敏感性功能膜在物质的分析与检测,混合物的分离与纯化过程中的应用前景。  相似文献   

2.
综述了生物可降解高分子材料的发展情况及其在药物释放领域的应用 ,着重介绍了聚乳酸和聚己内酯的研究进展和应用  相似文献   

3.
聚己内酯微粒的生物降解行为   总被引:6,自引:0,他引:6  
由于微包囊药物制剂具有降低药物毒副作用、防止药物失活、减少服药次数以及靶向给药的效果,从而既可提高病灶部位的药物浓度,又可减小对机体其它部位的损伤,因此成为较理想的药物释放体系,以至目前在药物释放体系中,微包囊药物释放体系得到了广泛的应用.生物降解性高分子是理想的药物包裹材料,由于它在药物释放完毕后可以在体内降解、而后被机体代谢或吸收,不需再手术取出,因此,用高分子微包囊药物释放体系治疗癌症等疑难病症正在成为国际上共同的研究热点[1].聚己内酯(PCL)是兼具良好力学性能和药物通透性能的生物降解…  相似文献   

4.
利用Langmuir-Blodgett(LB)膜技术能够使薄膜中聚合物分子链获得高度有序的排列与组装,并使沉积后的膜具备可控的特殊结构以及不同寻常的物理化学性质.高分子LB膜可用于制造非线性光学材料、光电子器件、传感器单元、电极修饰膜,也可作为研究催化反应、电子转移、仿生模拟的理想模型.本文评述了芳杂环类合成高分子(聚酰亚胺、聚噻吩、聚乙烯基咔唑和聚苯胺)与几种天然高分子(木质素、纤维素、壳聚糖和蛋白质)的LB膜最近的研究进展,并详细讨论了高分子LB膜的制备、结构与表征,指出了这两类高分子LB膜的研究重点,并对该两类高分子LB膜潜在的应用进行了展望.  相似文献   

5.
可生物降解的高分子类型,合成和应用   总被引:28,自引:0,他引:28  
综述了生物降解高分子的定义,实现生物降妥的主要方法和生物降解高分子主要类别,以及它们在生物医学领域及环保事业等方面的重要用途和意义。阐明了影响生物降解速度的主要因素,对控制,调节生物降解速度的订研究动态进行了介绍。  相似文献   

6.
全氟磺酸离子交换膜的制备与性能研究   总被引:7,自引:0,他引:7  
采用四氟乙烯、六氟丙烯和全氟磺酰基乙烯基醚共聚合成了全氟磺酸离子交换树脂,通过溶液浇铸法将其制成全氟磺酸离子交换膜(PSALM)。PSALM膜显示出优良的力学性能、电化学性能以及化学稳定性。TGA测试结果表明,PSALM膜的初始热分解温度超过400℃;DSC测试结果显示,膜中存在微观相分离,该膜具有三个热转变温度,分别对应于非晶区、离子簇区和结晶区。  相似文献   

7.
张新民 《合成化学》2000,8(6):519-524
合成了一种新的聚合物聚L-谷氨酸-5-(6′-己二醇肉桂酸酯基),研究了它在空气/水界面的行为,形成LB膜能力,液晶性质及光交联反应。  相似文献   

8.
生物降解性聚己内酯-聚醚嵌段共聚物的合成及表征   总被引:8,自引:2,他引:8  
A new biodegradable Poly (e-caprolactone)-Poly (ethylene glycol) block copolymer (PCL-b-PEG) has been synthesized by co-polycondensation reaction of e-caprolactone (e-CL) and poly (ethylene glycol) (PEG) in the presence of Ti(OBu)4 catalyst. The composition,hy-drophilicity and crystallinity of the copolymer can be controlled by changing the feeding dose of reaction system. The degradation rate of the PCL-b-PEG copolymer is improved by introducing the PEG segment, and the more the PEG content in the copolymers,the faster the degradation rate of the copolymer.  相似文献   

9.
可生物降解高分子的酶法合成和改性   总被引:10,自引:0,他引:10  
介绍了新型功能高分子材料-可生物降解高分子材料的研究概况,并重点评述了这一领域研究的新分支-酶法合成可生物降解高分子材料的新进展。  相似文献   

10.
以吡咯(Py)和聚ε-己内酯(PCL)为原料、氯仿为溶剂,并掺杂一定量的十二烷基硫酸钠制备电纺膜,利用三氯化铁的氧化作用原位生成聚吡咯(PPy).对所得到的PCL/PPy电纺膜用红外光谱进行表征,在扫描电镜和透射电镜下观察纤维形貌,并测定力学性能和体积电阻率.结果表明,所生成的PPy以纳米粒子形式附着在电纺纤维表面,随着Py相对于PCL的质量百分含量由0增加到20%,PCL/PPy电纺膜的纤维直径从(730±341)nm逐渐下降至(325±84)nm;膜的拉伸模量和拉伸强度由不含Py的(25.7±0.8)MPa和(2.48±0.14)MPa分别增加至含有20%Py的(48.4±7.6)MPa和(5.05±0.59)MPa,断裂伸长率由(129±27)%下降至(86.2±9.1)%;体积电阻率降低了2~3个数量级.该PCL/PPy电纺纤维膜以期可作为电活性材料用于功能或生物医用领域.  相似文献   

11.
综述了可生物降解聚合物药物膜的组成、制备方法及其药物释放行为的影响因素,为可生物降解聚合物药物膜的研究开发提供参考。  相似文献   

12.
生物降解聚合物膜的制备及防肌腱粘连作用甘志华景遐斌*(中国科学院长春应用化学研究所高分子物理联合开放研究实验室长春130022)张仲文徐莘香(白求恩医科大学第一临床医院长春)关键词肌腱粘连,生物降解,聚合物膜1996-07-21收稿,1996-09-...  相似文献   

13.
生物降解聚合物的制备及防肌腱粘连作用   总被引:3,自引:0,他引:3  
  相似文献   

14.
高分子在溶液中的复合   总被引:1,自引:0,他引:1  
概括了高分子在溶液中复合的研究状况,一方面综述了研究高分子复合的各种实验方法;另一方面依据复合驱动力的不同,将高分子复合体系总结为对应的几类;以库仑力作用,氢键作用,范德力作用,电子转移作用,特殊离子相互作用稳定的复合体系,并分析别讨论了各类复合体系的影响因素。  相似文献   

15.
8-羟基喹啉铝高分子薄膜的荧光特性   总被引:5,自引:0,他引:5  
In this paper, the solid state. polymer thin films of 8-hydroxylquinoline aluminum (Alq3) were made by spinning coat method. The fluorescence efficiencies and the luminescence spectra of them were measured via the laser systems. Various experimental factors were considered and tested. It was found that the peak wavelength of the luminescence spectra of the Alq3 polymer films shifted and that the purity of the samples affected its fluorescence efficiencies: the fluorescence efficiencies of impure samples were about three-fourth of that of the purified ones; fluorescence efficiencies of Alq3 doped in PMMA polymer was higher than that doped in PC and PEO. Under certain conditions, transparent thin film 10 layers can be achieved. This kind of polymer thin film of Alq3 exhibits well fluorescence response, but also has good stability. Spin coat method can greatly reduce the technical requirements comparing with the vacuum plating method.  相似文献   

16.
To date, significant efforts have been dedicated to improve their ionic conductivity, thermal stability, and mechanical strength of solid polymer electrolytes (SPEs). However, direct monitoring of physical and chemical changes in SPEs is still lacking. Moreover, existing thermosetting SPEs are hardly degradable. Herein, by overcoming the limitation predicted by Flory theory, self-reporting and biodegradable thermosetting hyperbranched poly(β-amino ester)-based SPEs (HPAE-SPEs) are reported. HPAE is successfully synthesized through a well-controlled “A2+B4” Michael addition strategy and then crosslinked it in situ to produce HPAE-SPEs. The multiple tertiary aliphatic amines at the branching sites confer multicolour luminescence to HPAE-SPEs, enabling direct observation of its physical and chemical damage. After use, HPAE-SPEs can be rapidly hydrolysed into non-hazardous β-amino acids and polyols via self-catalysis. Optimized HPAE-SPE exhibits an ionic conductivity of 1.3×10−4 S/cm at 60 °C, a Na+ transference number ( ) of 0.67, a highly stable sodium plating-stripping behaviour and a low overpotential of ≈190 mV. This study establishes a new paradigm for developing SPEs by engineering multifunctional polymers. The self-reporting and biodegradable properties would greatly expand the scope of applications for SPEs.  相似文献   

17.
The thermal induced topography change in a model system consisting of a polymer film on a Si substrate capped by a thin metal layer has been studied by using AFM. Regular lateral patterns over large areas were observed on the surface when the system was heated to a sufficiently high temperature. 2D-FFT analysis to the AFM images indicates that the patterns are isotropic and have well defined periodicities. The periodicities of the characteristic patterns are found to depend strongly on the annealing temperature. The study of the ki-netics of the formation reveals that such a topography forms almost instantaneously once the critical tempera-ture is reached. It is suggested that this wave-like surface morphology is driven by the thermal expansion co-efficient mismatch of the different layers. This method for generating regular wave-like patterns could be used as a general method for patterning various organic materials into micro/nanostructures.  相似文献   

18.
Organic memristors with low power consumption, fast write/erasure speed, and complementary metal-oxide-semiconductor(CMOS) compatibility have attracted tremendous attention to mimic biological synapses to realize neuromorphic computation in recent years. In this paper, organic resistive switching memory(ORSM) based on (Z)-3-(naphthalen-2-yl)-2-(4-nitrophenyl)acrylonitrile(NNA) and polymer poly(N-vinylcarbazole)(PVK) composite film was prepared by spin-coating method. Device performance based on NNA:PVK composite films with different mass fractions of NNA were systematically investigated. The ORSM based on PVK:40%(mass fraction) NNA composite film exhibited non-volatile and bipolar memory properties with a switching ratio(Ion/Ioff) of 24.1, endurance of 68 times and retention time of 104 s, a “SET” voltage(Vset) of -0.55 V and a “RESET” voltage(Vreset) of 2.35 V. The resistive switching was ascribed to the filling and vacant process of the charge traps induced by NNA and the inherent traps in PVK bulk. The holes trapping and de-trapping process occurred when the device was applied with a negative or positive bias, which caused the transforming of the conductive way of charges, that is the resistive behaviors in the macroscopic. This study provides a promising platform for the fabrication of ORSM with high performance.  相似文献   

19.
聚合物熔体膜在基体表面上的润湿和铺展行为受铺展系数和Hamaker常数影响。对于不能在基体表面上铺展的聚合物膜,当处于其玻璃化温度以上时,聚合物熔体膜将破裂,出现非连续区域。随着体系处于聚合物玻璃化温度以上时间的延长,非连续部分尺寸不断增长,增长速率与表面张力、聚合物粘度、聚合物液滴在基体表面的平衡接触角等因素有关,平衡后聚合物以液滴的形式在基体表面稳定存在。将带功能端基聚合物加入不能在基体表面上铺展的聚合物中,通过修饰聚合物与基体界面或改变聚合物熔体膜的表面张力,可以使原来不能在基体表面铺展的聚合物保持稳定。本文综述了聚合物熔体膜的铺展和润湿动力学研究进展,并归纳了使聚合物熔体膜稳定的方法。  相似文献   

20.
聚合物网络分散液晶复合膜的制备与性能研究   总被引:1,自引:0,他引:1  
报道了一种新型树脂基的聚合物网络分散晶复合膜材料。研究了基体材料的组成,液晶种类,液晶含量,聚合温度,紫外光强度及聚合时间等聚合物网络分散液晶复合膜性能的影响。扫描电子显微镜观测,发现这种材料是由两个连相互穿构成了属于聚合物球型。  相似文献   

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