强碱性离子交换纤维的结构与性能

聚丙烯基强碱性离子交换纤维是由聚丙烯(polypropylene,简称PP)纤维与苯乙烯-二乙烯苯经60Coγ射线共辐照接枝后再经氯甲基化和胺化反应后制得的.为了研究自制的离子交换纤维的物理化学结构特点、活性功能基、微观形貌等特征.本文运用IR、DSC、SEM等现代测试表征技术结合元素分析、滴定曲线、交换容量、吸附动力学性能、机械强度和化学稳定性的测定等方法对离子交换纤维进行了较系统的分析.结果表明:自制的离子交换纤维具有强碱性离子交换纤维的结构特征和一定的化学稳定性.     

聚丙烯基强碱性阴离子交换纤维的结构表征及性能研究

采用共辐射引发接枝共聚法在聚丙烯纤维上接枝苯乙烯-二乙烯苯,通过氯甲基化反应和胺化反应制备强碱性阴离子交换纤维.利用分析仪器对制备产品的结构进行表征,并对其溶胀性、机械强度、吸附交换性能等物理和化学性能进行了测定.结果表明,制备的强碱性阴离子交换纤维具有较高的交换容量、快的吸附速度、较好的机械性能和稳定的化学性能,是一种性能优良的离子交换材料.     

原硅酸钠改性的聚偏氟乙烯接枝苯乙烯磺化膜接枝率的影响因素

以过氧化苯甲酰(BPO)作引发剂,通过溶液接枝聚合法把苯乙烯接枝到原硅酸钠改性的聚偏氟乙烯(PVDF)膜上,磺化后得到聚偏氟乙烯接枝苯乙烯磺酸(PVDF-g-PSSA)电解质膜。讨论了原硅酸钠的用量、接枝反应时间、反应温度、BPO浓度、苯乙烯单体浓度等对PVDF-g-PSSA膜接枝率的影响。结果表明,原硅酸钠用量为10%(质量分数,下同)、BPO浓度为0.016mol/L反应液、苯乙烯与四氢呋喃的比例为4∶1、在75℃水浴中,氮气保护下反应10h,可得到接枝率为16.1%、电导率为1.6×10-2S/cm的PVDF-g-PSSA电解质膜。     

后交联纤维的制备及吸附性能研究

用对二氯甲基苯作为后交联剂,与聚丙烯接枝苯乙烯-二乙烯苯纤维进行后交联反应,制备出具有高比表面积的后交联纤维.对影响反应的各种因素:反应温度、时间、催化剂和配料比进行了研究,得出最优化的制备条件.并且在静态条件下,研究了水溶液中后交联纤维吸附吡啶的热力学特性,测定了不同温度下的吸附等温线.结果表明,后交联纤维吸附吡啶符合Freundlich模型,表现为放热的物理吸附过程,而且是自发进行的.     

磺化热压PPS非织毡的性能研究

利用磺化反应及热压处理改善聚苯硫醚(PPS)非织毡的亲水性和离子交换能力,讨论了时间、温度、热压压力等不同反应条件对PPS亲水性及离子交换能力的影响.实验结果表明,在磺化反应温度为80℃,反应时间为1.5h的磺化反应条件及热压压力为9 MPa条件下,不仅PPS非织毡的亲水性和离子交换能力得到了显著的改善,同时还保留了较好的力学性能和耐腐蚀性.     

有机气凝胶的磺化研究

选用纳米结构有机气凝胶为基体,通过磺化制备强酸型有机气凝胶吸附分离材料.阐明有机气凝胶的制备工艺(磺化温度、磺化时间、磺化剂浓度及固液比)对产品性能的影响.制得纳米网络状强酸型吸附分离材料,其交换容量可达6～7mmol/g,具有较好的应用前景.     

褐煤腐植酸磺化工艺研究

以褐煤腐植酸、Na2SO3、NaOH为原料对褐煤腐植酸进行磺化改性;采用电导法对其磺化度进行测定;通过考察固液比、反应时间、反应温度对磺化腐植酸磺化度的影响获得最佳工艺参数：磺化剂与腐植酸钠溶液的液固比2：20、磺化温度50℃、磺化时间90min;产品磺化度为17．7％;红外光谱表明,磺化腐植酸中磺酸基团明显增多,确实发生了磺化反应。     

无皂乳液聚合法制备PS/TiO2核-壳复合微球

采用无皂乳液聚合法制备聚苯乙烯(PS)微球,将所制备的PS微球经磺化吸水后,利用钛酸丁酯作前驱体在乙醇中反应,使TiO2包覆在磺化苯乙烯微球表面,得到有机-无机PS/TiO2复合微球。在所得的杂化微球表面接枝上可聚官能团,利用无皂乳液聚合将聚甲基丙烯酸甲酯聚合到微球表面,得到核-壳-壳杂化微球。用FT-IR、SEM和TGA等方法对所制得的复合微球进行表征。结果表明PS、PS/TiO2及PS/TiO2/PMMA微球表面光滑,球形度好,单分散性良好;通过改变TBOT的加入量可以控制TiO2对PS微球的包覆厚度。     

PPS基强酸离子交换纤维的制备及对Cr(Ⅲ)的吸附性能

通过聚苯硫醚(PPS)纤维的烷基化交联与磺化反应制得一种强酸离子交换纤维新材料。以此为基础,利用元素分析、红外光谱、原子吸收及化学滴定等手段对其物理化学结构与性能进行分析和表征,考察不同因素对交联与磺化反应的影响及纤维对水溶液中Cr(Ⅲ)的吸附、解吸与再生性能。研究表明,适度交联可有效提高离子交换纤维的化学稳定性,由此制得的PPS基强酸纤维交换容量可达2.634 mmol/g;纤维对水溶液中Cr(Ⅲ)的吸附容量高达59.43 mg/g,经6次吸附洗脱循环后吸附性能亦无明显变化,可望在工业含铬废水处理等工艺中获实际应用。     

一种强阳离子交换填料的制备及其在奶粉中二聚氰胺检测中的应用

采用悬浮聚合法合成了以苯乙烯-二乙烯苯共聚物为基质的固相萃取交换填料,并对该填料进行功能化修饰,得到对碱性化合物具有较高选择性的强阳离子交换型填料。结合高效液相色谱法,将其应用于奶粉中二聚氰胺的检测,得到的回收率分别为95.21%、96.29%和94.91%,相对标准偏差分别为5.12%、4.28%和4.69%,符合分析要求,具有广泛的应用前景。     

Ibuprofen ion-exchange fiber complex: improved dissolution and gastric tolerance based on ion exchange

The purpose of the present study is to develop a novel method to improve the dissolution of water-insoluble drug ibuprofen and the gastric tolerance of this non-steroidal anti-inflammatory drug which has potentially serious gastrointestinal side effects. This method is based on ion exchange of ion-exchange fibers. Water-insoluble drug ibuprofen was dispersed in deionized water, and then the ion-exchange fibers in OH^– type was immersed in it. Ibuprofen and the active groups of the ion-exchange fibers combined into ion pairs based on the acid–base reaction. This drug carrier did not release drugs in deionized water, but in water solution containing other ions it would release the drugs into the solution by ion exchange. Confirmed by the X-ray diffraction and the scanning electron microscopy, the ibuprofen combined onto the ion-exchange fibers was in a highly molecular level dispersed state. The improved dissolution of ibuprofen ion-exchange fiber complexes is likely to originate from this ibuprofen’s highly dispersed state. Due to this, ibuprofen’s highly dispersed state, ibuprofen ion-exchange fiber complexes significantly decreases the gastrointestinal side effects of ibuprofen by avoiding the solid ibuprofen’s educing. The present study showed that ibuprofen ion-exchange fiber complexes have the two-fold advantages. One is to improve the dissolution of ibuprofen. The other is to decrease the ibuprofen’s gastrointestinal toxicity.     

离子交换纤维对红霉素吸附特性的研究

采用自制的弱酸离子交换纤维对红霉素的吸附和洗脱性能进行了研究,考察了温度、酸度及吸附时间等因素对吸附性能的影响.实验结果表明,pH值为7.0时吸附性能最好.离子交换纤维对红霉素的吸附以液膜扩散为主.静态饱和吸附量为1.79×10~5u/g干纤维,等温吸附过程服从Langmuir和Freundlich等温吸附方程.pH值为7.0,流速为5.0ml/min时对红霉素的动态吸附容量为4.54×10~5u/g干纤维.选用0.1mol/L CH_3COONH_4溶液进行洗脱,当洗脱液流速为5.0ml/min,用量为80ml时洗脱率为92.5%.离子交换纤维的吸附量和洗脱率与大孔树脂类似,吸附速率远大于大孔树脂,能再生重复使用,是一种优秀的红霉素吸附材料.     

Interfacial microstructure and mechanical properties of carbon fiber composites by fiber surface modification with poly(amidoamine)/polyhedral oligomeric silsesquioxane

Polyhedral oligomeric silsesquioxane (POSS) was grafted onto carbon fiber surface using poly(amidoamine) (PAMAM) as a novel coupling agent at mild reaction conditions. Firstly, the reinforcement was designed with propagation of PAMAM on the fiber surface by in situ polymerization to improve the surface activities of carbon fiber. Secondly, the POSS further grafted on the fiber could significantly enhance fiber surface energy and wettability, which would greatly increase the interfacial strength of fiber-matrix. The microstructure and mechanical properties of carbon fiber and the resulting composites were investigated. The results indicated that PAMAM and POSS, which could significantly increase the surface roughness and wettability of carbon fiber, were successfully grafted on the fiber surface. Compared with the desized fiber composites, the interlaminar shear strength and the interfacial shear strength of the modified carbon fiber composites increased by 48% and 89%, respectively.     

离子交换纤维对绿原酸吸附特性的研究

研究了绿原酸在自制的强碱性阴离子交换纤维上的静态吸附行为，结果表明：该离子交换纤维对绿原酸的静态饱和吸附容量为252．2mg／g；等温吸附曲线服从Langmuir等温吸附式和Freundlich经验式；表观活化能Eα=15．498kJ／mol；表观速率常数随温度的升高而增大。用一定体积比的稀HCl-甲醇复合溶剂可将纤维上的绿原酸洗脱。     

Controlling of the interfacial shear strength between thermoplastic resin and carbon fiber by adsorbing polymer particles on carbon fiber using electrophoresis

In order to control the interfacial adhesion between carbon fibers and thermoplastic resins, poly(methyl methacrylate) (PMMA) particles have been adsorbed on the carbon fiber surfaces using an electrophoresis process. The amount of PMMA particles adsorbed on the modified carbon fibers was varied using the electrophoresis technique performed in polymer colloids for a short time. Additionally, the interfacial shear strength between the modified carbon fiber and the resin was controlled by a modification of the present process. An improved interaction and a strengthened surface adhesion between the carbon fiber coated with particles and the PMMA resin were observed.     

氨基膦酸螯合纤维的制备及性能研究

氨基膦酸螯合纤维是以聚丙烯接枝苯乙烯氯甲基化纤维为原料,经过胺化反应和膦酸化反应后制得的。研究了胺化温度和胺化时间对纤维增重率的影响,运用正交实验优化了氨基膦酸纤维制备工艺。结果表明,氨基膦酸纤维对Cu2+的最大饱和螯合吸附容量为77.6mg/g,在相同质量浓度的Cu2+和Ni 2+的混合溶液中能把两种离子完全分开。运用元素分析(EA)、IR、SEM和TG等测试手段对自制纤维的性能进行了系统研究。     

Preparation of an ion-exchange chromatographic support by a "grafting from" strategy based on atom transfer radical polymerization

A new "grafting from" strategy based on surface-initiated atom transfer radical polymerization (ATRP) was first used for the preparation of a polymer-based ion-exchange support for HPLC. The most important property of the proposed method is to be applicable for the synthesis of any type of ion exchanger in both the strong and the weak forms. Monodisperse, porous poly(glycidyl methacrylate-co-ethylene dimethacrylate), poly(GMA-co-EDM) particles 5.8 mum in size were synthesized by "modified seeded polymerization". Poly(dihydroxypropyl methacrylate-co-ethylene dimethacrylate), poly(DHPM-co-EDM) particles were then obtained by the acidic hydrolysis of poly(GMA-co-EDM) particles. The ATRP initiator, 3-(2-bromoisobutyramido)propyl(triethoxy)silane was covalently attached onto poly(DHPM-co-EDM) particles via the reaction between triethoxysilane and diol groups. In the next stage, the selected monomer carrying strong cation exchanger groups, 3-sulfopropyl methacrylate (SPM), was polymerized on the initiator-immobilized particles via surface-initiated ATRP. The degree of polymerization of SPM (i.e., length of polyionic ligand) on the particles was precisely controlled by adjusting ATRP conditions. Poly(SPM)-grafted poly(DHPM-co-EDM) particles obtained with different ATRP formulations were tried as chromatographic packing in the separation of proteins by ion-exchange chromatography. The proteins were successfully separated with higher column yields with respect to the previously proposed materials. The plate heights between 100 and 150 mum were achieved with the column packed with the particles carrying the shortest poly(SPM) chains. The plate height showed no significant increase with increasing flow rate in the range of 0.5-16 cm/min.     

In vitro cytotoxicity of E-glass fiber weave preimpregnated with novel biopolymer

The aim of this study was to investigate cytotoxicity of composition of E-glass fibers and novel biopolymer of poly(hydroxyproline). Growth and proliferation of the human gingival fibroblast cells on the surface of the materials was evaluated. The number of cells grown and proliferated on cell culture plastic was used as a control. Bi-directional fiber weaves were preimpregnated with poly(hydroxyproline). Cytotoxicities of the preimpregnated and nonimpregnated materials were evaluated bythe release of lactate dehydrogenase from the cells during the culture period of 24 h. The values of the lactate dehydrogenase activity of the materials' extracts showed non-toxicity for poly(hydroxyproline) preimpregnated E-glass fiber weaves. The growth of fibroblasts on the surface of the materials appeared normal after 11 days culture period; they looked healthy and normal in size and shape. The results of this study suggest that based on its' non-cytotoxicity the composition of E-glass fibers and poly(hydroxyproline) can further be evaluated as a material that is suitable for biomedical use.     

In vivo assessment of novel furosemide gastro-mucoadhesive delivery system based on a kind of anion ion-exchange fiber

A novel gastro-mucoadhesive delivery system based on a kind of anion ion-exchange fiber has been developed. Furosemide (FM), which is site-specifically absorbed from the upper gastrointestinal (GI) tract, was used as model drug. A novel-modified dissolution system, which can also be called "flow through diffusion cell," was used to study the drug release from the drug fibers. The GI transit studies of the FM fiber complexes in rats and gamma imaging studies in volunteers were carried out to evaluate the gastro-mucoadhesive behavior of the fiber. The pharmacokinetic profile and parameters of the FM suspension and FM fiber in fasted and fed rats were measured, respectively. Studies on rats and volunteers provided evidence for the validity of the hypothesis that the drug fiber provided better gastro-mucoadhesive properties in vivo.     

Cellulose fiber/poly(ethylene-co-methacrylic acid) composites with ionic interphase

Cellulose fiber/thermoplastic composites with ionic interphase were prepared from modified cellulose fibers and poly(ethylene-co-methacrylic acid) (PE-co-MA). The cellulose fiber was treated by using coupling agent or sodium hydroxide followed by introduction of ionic quaternary ammonium groups on the fiber surface, which was then compounded with the polymer having anionic groups. The effect of the ionic interface on the composite physical and thermal dynamic properties was investigated. An obvious improvement in mechanical strength of the ionic-interface composites was observed due to acid–base interactions. The improved adhesion could be ascribed to the interaction between cationic grafted groups at the cellulose fiber surface and the anionic groups in the PE-co-MA.