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1.
甲基丙烯酸丁酯/苯乙烯共聚物纤维的制备和性能   总被引:2,自引:0,他引:2  
以过氧化苯甲酰(BPO)为引发荆,采用水相悬浮聚合法合成了甲基丙烯酸丁酯(BMA)/苯乙烯(St)共聚物,将共聚物溶于N,N-二甲基乙酰胺(DMAc)中配制成纺丝溶液,将其用湿法纺丝成形后制备出具有吸附弱极性液态有机物(油品)功能的甲基丙烯酸丁酯/苯乙烯共聚物纤维.用傅里叶红外光谱仪(FTIR)和1H核磁共振波谱仪(NMR)研究了共聚物的化学结构,用热重分析仪(TG)、动态热机械分析仪(DMA).单丝强力仪等对纤维的相关性能进行了分析.结果表明,BMA/St70/30共聚物纤维的性能良好,对煤油.石油醚和庚烷等油品的饱和吸附率分别达到3.7g/g纤维、5.3 g/g纤维和4.1 g/g纤维.  相似文献   

2.
Biodegradable radiopaque iodinated polyurethanes (I-PUs) based on poly(ε-caprolactone) diol (PCL) as soft segment have been synthesized using 4,4′-isopropylidene-(2,6-diiodophenol) (IBPA) as chain extender. In order to elucidate the effect of iodinated chain extender on degradation properties of I-PUs, a control polyurethane with bisphenol A as chain extender was also synthesized. The enzymatic degradation study of these I-PUs was carried out using phosphate-buffered solution (pH 7.4) at 37 °C. The mass loss, surface morphology, iodine content, radiopacity, hydrophilicity and thermal properties of the samples during degradation were characterized with scanning electron microscopy (SEM), energy-dispersive X-ray detector (EDX), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and static contact angle. Results of enzymatic degradation during 3 months indicated that the incorporation of iodinated chain extender greatly hindered the in vitro degradation of I-PUs compared with the control PU-C sample. The reason for the retarded degradation was attributed to the bulky iodine atoms on IBPA chain extender with steric hindrance, which decreased the surface hydrophilicity of I-PUs and slowed water/lipase diffusion rate. Moreover, the radiopacity of I-PUs does not sharply attenuate after long-time degradation, which is useful for interventional biomedical applications.  相似文献   

3.
以丙烯腈(AN)和甲基丙烯酸甲酯(MMA)为单体,在钛酸丁酯水解生成的TiO2粒子表面乳液聚合制备复合聚合物P(AN-MMA)/TiO2,并以此聚合物制备了多孔复合聚合物膜。采用核磁共振(NMR)、红外光谱(FT-IR)、差热分析(DSC)、扫描电镜(SEM)等对聚合物膜进行了表征,并测试了所得聚合物电解质的交流阻抗谱。结果表明,AN和MMA通过打开各自的C=C双键形成共聚物,TiO2在基体中分散均匀。当TiO2添加量为10.8%时,复合聚合物电解质的室温离子电导率达到1.12×10-3S/cm。  相似文献   

4.
Preparation of crosslinked copolymer beads based on glycidyl methacrylate (GMA), 2-hydroxyethyl methacrylate (HEMA), and divinyl benzene for the use of heavy metal adsorption has been investigated. In our study, a series of porous copolymer beads were synthesized by suspension polymerization in the presence of porogens, 1-dodecanol, toluene, and heptane at different dilutions. The effect of the porogens on the surface appearance and the porous structure of copolymer beads was studied by scanning electron microscopy and BET method. Diethylene triamine chelating copolymers were obtained through a reaction between amine groups of diethylene triamine and epoxide pendant groups of GMA. Adsorption isotherm and quantitative analysis for adsorption capacity involving copper, chromium, manganese, cadmium, iron, and zinc ions were investigated using atomic absorption spectrophotometer. The adsorption was a function of types of metal ions, adsorption time, and solution properties including pH and metal concentration. Adsorption equilibrium was achieved in approximately 50 min with a maximum adsorption capacity at pH 5.0. The Langmuir isotherm was found to be well fitted on the adsorption behavior. The maximum metal adsorption capacities in single ion solution in mole basis were in the order Cu(II) > Cr(VI) > Mn(II) > Zn(II) > Cd (II) > Fe(II). It was found that introducing porogen in the polymerization mixture produced the copolymer beads with better adsorption capacity. The maximum Cu(II) adsorption capacity of chelating poly(GMA-co-HEMA) beads were 1.35 mmol/g (85.79 mg/g) measured from the beads prepared in the presence of 1-heptane with 50% dilution. Consecutive adsorption–desorption experiments showed that crosslinked poly(GMA-co-HEMA) micro-beads can be reused almost without any change in the adsorption capacity.  相似文献   

5.
New radiopaque nanocomposites were prepared based on iodinated polyurethane–urea (PUU) and graphene oxide (GO). The iodinated PUU was synthesized using 4,4′-methylenediphenyl diisocyanate (MDI), polyethylene glycol (PEG, Mn?=?1000), and 4-(4-iodophenyl)-1,2,4-triazolidine-3,5-dione (IUr) as a novel chain extender and radiopacifying agent. The synthesized urazole, PUU, and the related nanocomposites are characterized by fourier transform infrared spectrum, nuclear magnetic resonance, X-ray diffraction, field-emission scanning electron microscopy, elemental analysis (CHNO), thermogravimetric analysis, and dynamic mechanical thermal analysis (DMTA). The X-ray visibility of the radiopaque PUU and nanocomposites was investigated using X-radiography. To evaluate the biocompatibility of the samples, the indirect MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay was carried out on the non-cancerous mouse fibroblast cell line NIH3T3 D4 according to the ISO10993-5 standard. The DMTA results proved introduction of the GO layers into the iodinated PUU matrix, and has improved mechanical properties of the nanocomposites compared to the pure polymer. The X-ray images showed significant radiopacity of the pure polymer and the nanocomposites.  相似文献   

6.
The synthesis of a new hybrid composite based on PbS nanoparticles and poly(methyl methacrylate-2-acrylamido-2-methylpropane sulfonic acid) [P(MMA-AMPSA)] copolymer is reported. The chemical synthesis consists in two steps: (i) a surfactant-free emulsion copolymerization between methyl methacrylate and 2-acrylamido-2-methylpropane sulfonic acid and (ii) the generation of PbS particles in the presence of the P(MMA-AMPSA) latex, from the reaction between lead nitrate and thiourea. The composite was studied by scanning electron microscopy (SEM), X-ray diffraction, FTIR spectroscopy, thermogravimetric analysis and differential scanning calorimetry. The microstructure observed using SEM proves that the PbS nanoparticles are well dispersed in the copolymer matrix. The X-ray diffraction measurements demonstrate that the PbS nanoparticles have a cubic rock salt structure. It was also found that the inorganic semiconductor nanoparticles improve the thermal stability of the copolymer matrix.  相似文献   

7.
在超声辐射作用下,以α-溴代丙酸乙酯为引发剂,溴化亚铜/2,2-联吡啶为催化体系,通过原子转移自由基聚合(A-TRP)制备了分子链末端含有一个α-溴原子的聚甲基丙烯酸甲酯(PMMA-Br)。以此为大分子引发剂引发苯乙烯单体进行ATRP反应,制得聚甲基丙烯酸甲酯嵌段聚苯乙烯(PMMA-b-PS)共聚物。通过硼氢化钠还原聚合物体系中的溴化亚铜,从而得到纳米铜/PMMA-b-PS复合粒子。红外光谱(FT-IR)和核磁共振(1H-NMR)表征嵌段共聚物的结构;凝胶渗透色谱(GPC)测定了共聚物的相对分子量和多分散系数;X射线光电子能谱(XPS)证明纳米铜和PMMA-b-PS嵌段共聚物中PMMA之间存在一定的相互作用;通过高分辨透射电子显微镜(HTEM)观察到纳米铜具有诱导聚合物组装的现象。  相似文献   

8.
PP/PA1010共混物的形态结构及力学性能的研究   总被引:8,自引:0,他引:8  
利用红外光谱、扫描电子显微镜和力学测试等方法, 甲基丙烯酸环氧丙酯熔融接枝聚丙烯PP-g-GMA对不同组成的PP/PA1010共混物形态结构和力学性能的影响。  相似文献   

9.
以块体SiO2大孔材料为基质,甲基丙烯酸缩水甘油酯(GMA)和甲基丙烯酸羟乙酯(HEMA)为功能单体,通过原位聚合和溶剂蒸发制备P(GMA-co-HEMA)/SiO2大孔复合材料,用SEM、EDS、BET、FTIR和TGDTA对样品进行表征,并将其用于固定褶皱假丝酵母脂肪酶(CRL)。结果表明:SiO2大孔材料很强的毛细管作用使共聚物均匀地涂敷在其孔壁上,形成P(GMA-co-HEMA)/SiO2复合纳米薄膜。共聚物的负载量和亲疏水性可分别通过改变单体浓度和体积比进行调控,当单体体积浓度为10%、GMA和HEMA的体积比为9∶1时大孔复合材料固定化脂肪酶比酶活达到最高,为3 886.9U/g,与底物反应重复操作8批次后剩余酶活率为68.7%。  相似文献   

10.
利用表面原子转移自由基聚合(SI-ATRP)法,在硅基体表面接枝了以甲基丙烯酸甲酯(MMA)和甲基丙烯酸十二氟庚酯(DFHM)为单体的嵌段聚合物刷(Si-g-PMMA-b-PDFHM)。通过衰减全反射傅里叶变换红外光谱和X射线光电子能谱分析了聚合物刷的化学结构,采用气相色谱研究了2种聚合路线的反应动力学。进而通过扫描电子显微镜、原子力显微镜和接触角测量仪表征了聚合物刷的表面形貌及润湿性。结果表明,硅片表面引发SI-ATRP的反应动力学为典型的可控聚合反应,A、B方法的反应速率常数分别为0.04916/h和0.03731/h,转化率分别为55%和45%,聚合物刷的厚度分别为4.2μm和4.8μm。硅片表面生长聚合物刷后,粗糙度增加,疏水性能明显提高。  相似文献   

11.
Crosslinked macroporous hydrogels based on 2-hydroxyethyl methacrylate (HEMA)—[2-(methacryloyloxy)ethyl]trimethylammonium chloride (MOETACl) copolymer, HEMA-MOETACl—methacrylic acid (MA) terpolymer, and on a polyelectrolyte complex of HEMA—MA copolymer with poly(MOETACl) were prepared. All the hydrogels were prepared in the presence of fractionated sodium chloride particles. The hydrogels were characterized by the number of pores and the total volume of all pores in unit volume, the average volume and the average diameter of single pore. Morphology of the hydrogels was investigated by confocal and scanning electron microscopy. The hydrogels based on polyelectrolyte complexes were also characterized by chemical composition. Homogeneous (non-porous) hydrogels with the same composition as macroporous hydrogels were prepared and characterized by their biocompatibility.  相似文献   

12.
通过自由基共聚反应合成了以甲基丙烯酸缩水甘油酯(GMA)、甲基丙烯酸羟丙酯(HPMA)、丙烯酸异辛酯(EHA)及苯乙烯(St)为单体的共聚物P(GMA-HPMA-EHA-St)(PGHES),用含异氰酸根的不饱和单体丙烯酸羟乙酯(HEA)-异佛尔酮二异氰酸酯(IPDI)对PGHES进行接枝改性得到得到含聚氨酯(PU)结...  相似文献   

13.
以过氧化苯甲酰(BPO)为引发剂,采用悬浮聚合法制备了含有质量比为10%甲基丙烯酸β羟乙酯,0%~30%丙烯腈的甲基丙烯酸正丁酯/甲基丙烯酸β羟乙酯/丙烯腈P(BMA/HEMA/AN)三元共聚物。同时采用冻胶纺丝技术制备了对低分子有机液体具有吸附功能的纤维。通过红外光谱(FT-IR)、扫描电镜(SEM)等研究了共聚物的...  相似文献   

14.
Four series of macroporous hydrogels based on crosslinked copolymers of 2-hydroxyethyl methacrylate (HEMA)-sodium methacrylate (MANa), copolymer HEMA-[2-(methacryloyloxy)ethyl]trimethylammonium chloride (MOETACl), terpolymer HEMA-MANa-MOETACl and on a polyelectrolyte complex were used as carriers for immobilization of proteins, chicken egg white albumin and avidin. The adsorption capacity of the hydrogels for the two proteins, kinetics and pH dependence of albumin adsorption and desorption were studied. The morphology of the hydrogels with and without immobilized albumin was studied by low-vacuum scanning electron microscopy.  相似文献   

15.
申向  赵义平  陈莉  冯霞  张强 《功能材料》2011,42(1):74-76
制备了聚偏氟乙烯(PVDF)接枝N-异丙基丙烯酰胺(NIPAAm)共聚物(PVDF-g-PNIPAAm),进而采用干-湿法纺丝工艺,首次纺制出温敏PVDF-g-PNIPAAm中空纤维膜.通过红外光谱(FT-IR)、X射线衍射(XRD)、差示扫描量热仪(DSC)、扫描电镜(SEM)等对中空纤维膜的结构和形态进行了表征与研...  相似文献   

16.
以过硫酸钾为引发剂,水为分散介质,丙烯酸钠和甲基丙烯酸缩水甘油酯(GM A)共聚得共聚物P(AAN a-GM A),然后利用乙二胺(EDA)使氧杂环开环发生交联反应,制得高吸水性树脂。其结构经1H-NM R和IR表征。用茶袋法研究了乙二胺用量对树脂吸水能力的影响。结果表明,当n(EDA)/n(GM A)=0.35时,得到的树脂的吸水能力最大,达到527倍。  相似文献   

17.
2-hydroxyethyl methacrylate (HEMA) and 2,3-dihydroxypropyl methacrylate (DHPMA) were used to synthesize novel nanocomposites containing 0.5% by weight of copper hydroxylated nanoballs. Glass transition temperatures of the copolymers and their respective nanocomposites were determined by using differential scanning calorimetry (DSC). Thermogravimetric analysis (TGA) was employed to measure the degradation temperatures of the samples and to determine if the degradation is a single step process or multiple step process. The dielectric permittivity (epsilon') and loss factor (epsilon") were measured via Dielectric Analysis (DEA) in the frequency range 0.1 Hz to 100 kHz and between the temperature -150 to 190 degrees C. gamma, beta, and alphabeta conductivity relaxations were revealed using the electric modulus formalism. The activation energies for the relaxations were calculated. Argand plots of M" versus M' were used to study the viscoelastic effects of both copolymer and the composites. Herein we show that it is possible to tune solubility and relaxation properties which are important to the design of new biomaterials.  相似文献   

18.
The compositions of the copolymers of phenyl methacrylate and methyl methacrylate synthesized by free radical polymerization have been determined by nuclear magnetic resonance spectroscopy. X-ray diffraction analysis was employed for structural investigations. The results are discussed in terms of degree of amorphousness, interchain separation and mean crystallite size.  相似文献   

19.
采用甲基丙烯酸乙基咔唑酯(CEM)和N-乙烯基咔唑(NVC)的共聚合反应,合成了具有光导性能的甲基丙烯酸乙基咔唑酯/N-乙烯基咔唑(CEM/NVC)共聚物。讨论了影响共聚组成的因素,并用红外和紫外光谱对产物的结构进行了表征,通过元素分析方法分析了共聚物中各组分的百分含量,采用差示扫描量热(DSC)分析了共聚物的玻璃化温度(Tg),对掺有C60的CEM/NVC共聚物及聚乙烯咔唑(PVK)的光导性能进行了研究。结果表明,CEM含量增加对共聚物的Tg值降低明显;CEM含量越高,共聚物的Tg越低;共聚物比PVK的成膜性有明显提高;同时其对光导率影响不大。  相似文献   

20.
The hollow Au nanospheres were successfully prepared by the template method. The poly(styrene-co-2-aminoethyl methacrylate hydrochloride) (P(St-co-AEMH)) nanoparticles synthesized by the emulsion polymerization were used as the templates. After coating by Au colloidal nanoparticles and the formation of Au shells, the interior templates were etched out by sulfuric acid, leading to the formation of Au hollow nanospheres. The structure and morphology of the nanoparticles and hollow nanospheres were carefully investigated by the fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray analysis (EDX), wide-angle X-ray diffractometer (WAXD), and thermal gravimetric analysis (TGA) techniques.  相似文献   

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