高分子季铵盐型抗菌材料的制备

通过γ-氯丙基三甲氧基硅烷的偶联,将水溶性聚乙烯亚胺(PEI)接枝在纳米SiO2表面,随后分别用1-溴己烷和碘甲烷对接枝的PEI进行N-烷基化修饰,使PEI中的部分氨基转变成季铵盐,得到水不溶性QPEI/SiO2微粒。通过测定PEI/SiO2上PEI的接枝量,考察了各种反应条件对QPEI/SiO2微粒制备的影响规律。研究结果表明,纳米SiO2表面接枝PEI的适宜条件为:反应溶剂为DMF,反应温度90~100℃,反应时间8 h,氯丙基化SiO2与PEI质量比为4∶1,在此条件下制备的QPEI/SiO2微粒中PEI接枝量为14.8%。QPEI/SiO2微粒经甲基化修饰后,季铵盐含量由0.96%增加到3.37%,其抗菌性能显著增强。     

表面印迹法制备胆红素分子印迹材料及其识别性能

以g-(甲基丙烯酰氧)丙基三甲氧基硅烷(MPS)为媒介,将功能大分子聚乙烯亚胺(PEI)偶合接枝到硅胶微粒表面,形成了接枝微粒PEI/SiO2. 以胆红素为模板分子,乙二醇二缩水甘油醚(EGDE)为交联剂,采用分子表面印迹技术,制备了胆红素分子表面印迹材料MIP-PEI/SiO2,采用静态与动态两种方法研究了MIP-PEI/SiO2对胆红素的结合特性. 结果表明,印迹材料MIP-PEI/SiO2对胆红素分子具有特异的识别选择性与优良的结合亲和性,也具有优良的解吸性能,以EDTA与NaOH混合溶液作为洗脱液,11个床体积内解吸率可达99.39%.     

亚氨乙酸型螯合吸附材料IAA-PEI/SiO2对重金属离子的螯合吸附行为

将聚胺大分子聚乙烯亚胺(PEI)接枝于微米级硅胶微粒表面,制得接枝微粒PEI/SiO2,然后使氯乙酸与PEI大分子中的伯、仲胺基发生亲核取代反应,形成亚氨乙酸(IAA)型螯合吸附材料IAA-PEI/SiO2. 研究了IAA-PEI/SiO2对重金属离子的螯合吸附行为和吸附机理. 结果表明,由于亚氨乙酸基团与重金属离子之间的静电作用与配位螯合作用,IAA-PEI/SiO2对重金属离子可产生强的螯合吸附作用,对Ni2+的吸附容量可达1.4 mmol/g;吸附过程为放热过程;在可抑制重金属离子水解的pH范围内,pH值越高,吸附能力越强;IAA-PEI/SiO2对重金属离子的吸附容量顺序为Ni2+> Pb2+>Cu2+>Cd2+.     

聚乙烯亚胺修饰的氧化石墨烯对Cr(Ⅵ)的吸附性能研究

将聚乙烯亚胺(PEI)接枝到氧化石墨烯(GO)表面,得到聚乙烯亚胺修饰的氧化石墨烯(GO-PEI)材料。通过FTIR、XRD、TGA对GO-PEI的结构及PEI接枝量进行表征,并研究其对水中Cr(Ⅵ)的吸附性能。结果表明,PEI成功接枝到GO表面,其氨基含量为13.72 mmol/g。GO-PEI对Cr(Ⅵ)表现出优良的吸附性能,其吸附过程符合Langmuir等温吸附模型和准二级动力学模型。GO-PEI对Cr(Ⅵ)的去除是吸附与化学还原共同作用的结果。     

接枝型水不溶高分子抗菌材料的制备与抗菌特性

以接枝微粒氯甲基聚苯乙烯/硅胶(CMPSt/SiO2)为原料,用三乙胺(TEA)、三丁胺(TBA)及三苯基膦对其进行季铵(QN)化与季鏻(QP)化反应,制备了2种水不溶抗菌复合材料QN-PSt/SiO2与QP-PSt/SiO2;以大肠杆菌为致病菌体,采用平板活菌计数法研究了其抗菌性能及抗菌基团结构与抗菌性能的关系,采用胞外DNA和RNA测定法探索了其抗菌机理. 结果表明,2种材料具有很强的抗菌能力,QP-PSt/SiO2用量15 g/L时与浓度为109 mL-1的菌悬液接触1 min,杀菌率达100%. 影响复合微粒抗菌率的主要因素是抗菌基团的化学结构及其在材料表面的密度,接枝大分子链CMPSt的季铵(鏻)化程度即材料表面的季铵(鏻)基团密度越高,抗菌性能越强;季鏻盐型QP-PSt/SiO2的抗菌性能高于季铵盐型QN-PSt/SiO2;以三丁胺为季铵化试剂制备的QN-PSt/SiO2(TBA)的抗菌性能优于以三乙胺为季铵化试剂制备的QN-PSt/SiO2(TEA). QN-PSt/SiO2与QP-PSt/SiO2的抗菌作用实质是杀菌.     

季铵化聚乙烯亚胺的缓蚀与杀菌性能研究

制备了季铵化的聚乙烯亚胺(QPEI),采用静态挂片失重法研究了在0.5mol/L硫酸溶液中QPEI对低碳钢的缓蚀性能;以大肠杆菌(E.coli)为致病菌体,采用平板活菌记数法研究了QPEI的抗菌活性,并使用TTC-脱氢酶活性测定法,研究了QPEI的抗菌机理。结果表明,QPEI对低碳钢具有十分优良的缓蚀作用,同时具有很强的抗菌性能,其缓蚀作用抗菌作用基于杀菌过程,而不只是抑菌过程。     

聚(甲基丙烯酸甲酯)/聚乙烯亚胺-Cu~(2+)微粒的制备及其在苯酚湿法催化氧化中的应用

为降解工业废水中的苯酚及其衍生物,通过与聚乙烯亚胺(PEI)中的氨基络合将铜离子固定在聚甲基丙烯酸甲酯-聚乙烯亚胺(PMMA/PEI)微粒上,并以过氧化氢(H_2O_2)为氧化剂,将其应用于苯酚水溶液(1.0 g/L)的催化湿式过氧化氢氧化(CWPO)中。结果发现,该微粒是苯酚氧化降解的有效催化剂,其催化活性取决于多种反应因素。在反应温度为70℃、催化剂质量浓度为160 mg/L、氧化剂质量浓度为15.2 g/L、初始pH为5.0、反应时间为20 h的最佳反应条件下,苯酚的转化率约为96%,化学需氧量(COD)去除效率可达到90%。     

固载化亚胺乙酸-铜配合物催化剂在分子氧氧化有机物过程中的催化性能

利用接枝于微米级硅胶表面的聚乙烯亚胺(PEI)与氯乙酸反应,制备了亚胺乙酸(IAA)型复合螯合微粒IAA-PEI/SiO2,再使之与铜(Ⅱ)盐配位螯合,形成固载化亚胺乙酸-铜配合物Cu(Ⅱ)-IAA-PEI/SiO2。将微粒Cu(Ⅱ)-IAA-PEI/SiO2用作非均相催化剂,用于分子氧氧化乙苯与苯甲醇的氧化反应,研究了催化活性与催化氧化机理。研究结果表明,固载化亚胺乙酸-铜配合物Cu(Ⅱ)-IAA-PEI/SiO2可有效地催化分子氧氧化乙苯的过程,主产物为苯乙酮,在适宜的温度(130℃)与适宜的催化剂用量条件下,苯乙酮的得率为40%。Cu(Ⅱ)-IAA-PEI/SiO2与2,2,6,6-四甲基哌啶氧自由基(TEMPO)所构成的复合催化剂,可高效地催化分子氧氧化苯甲醇的氧化反应,产物为苯甲醛,在温和条件下(常压下的氧气、80℃),苯甲醇的转化率可达75%。     

烷基化聚乙烯亚胺接枝SiO_x抗菌剂用于聚乙烯的性能

以纳米SiOx粉体为载体,通过共价接枝修饰,制备出烷基化聚乙烯亚胺接枝SiOx纳米抗菌剂,将其添加到高聚物中制备出抗菌聚乙烯(PE)塑料。实验结果表明:纳米SiOx粉体已经成功接枝上了有机高分子基团,添加3%这种抗菌剂制备的抗菌PE塑料对大肠杆菌和金黄色葡萄球菌的抗菌率都大于96%,达到了强抗菌效果,并且制备的抗菌PE塑料具有良好的抗菌长效性。     

碳纳米管改性方法对聚酰胺11性能影响研究

采用酸处理和聚乙烯亚胺(PEI)表面修饰两种方法对多壁碳纳米管(MWCNTs)进行改性,将改性碳纳米管与聚酰胺11(PA11)熔融共混,制备了聚酰胺11/酸刻蚀碳纳米管(PA11/a-MWCNTs)和聚酰胺11/聚乙烯亚胺接枝碳纳米管(PA11/PEI-MWCNTs)复合材料,并通过扫描电子显微镜(SEM)、热重分析仪...     

Adsorption behaviour of functional grafting particles based on polyethyleneimine for chromate anions

Polyethyleneimine (PEI) was first grafted on the surfaces of micro-sized silica gel particles in the manner of the coupling graft, forming the grafting particles PEI/SiO₂. Afterward, for the grafted PEI, two polymer reactions, tertiary amination reaction and quaterisation, were allowed to be carried out in turn, and a kind of functional composite particles, QPEI/SiO₂, was obtained. QPEI/SiO₂ particles were used as solid adsorbent in the removal of chromate anions from aqueous solution. The static adsorption experiments (batch method) were performed, the effects of various factors on the adsorption capacity of QPEI/SiO₂ were examined, and the dynamic desorption experiments were also carried out. The experimental results show that QPEI/SiO₂ particles have strong adsorption ability for CrO₄²⁻ ions by right of electrostatic interaction, and the saturated adsorption amount actually reach up to 0.14 g/g. The isothermal adsorption behaviour is fitted to Langmuir model. The adsorption ability of QPEI/SiO₂ particles for CrO₄²⁻ ions is affected greatly by the quaterisation degree of the grafted PEI macromolecules. The QPEI/SiO₂ particles with higher quaterisation degrees have greater adsorption capacities. The adsorption ability of QPEI/SiO₂ particles for CrO₄²⁻ ions is nearly independent of pH values of the medium. QPEI/SiO₂ particles have excellent eluting and regenerating property as a mixed solution of NaOH and NaCl is used as eluent.     

非水介质中表面引发接枝聚合法制备接枝微粒PMAA/SiO2及其对阿魏酸的氢键吸附性能

以偶联剂γ-巯丙基三甲氧基硅烷(MPMS)对微米级硅胶微粒进行表面改性,制得表面键合巯基的改性微粒MPMS-SiO2. 在非水溶剂二甲基甲酰胺(DMF)中使偶氮二异丁腈(AIBN)与MPMS-SiO2表面的巯基(-SH)构成表面引发体系(-SH/AIBN),实现甲基丙烯酸(MAA)在非水介质中的表面引发接枝聚合,制得接枝度为20 g/100 g的接枝微粒PMAA/SiO2,对其进行了表征,考察了主要因素对MAA表面引发接枝聚合的影响规律,研究了PMAA/SiO2对酚酸化合物阿魏酸的氢键吸附作用. 结果表明,-SH/AIBN可顺利引发MAA在非水介质中的接枝聚合,适宜条件为75℃,AIBN用量为单体质量的1.5%. 在PMAA/SiO2与阿魏酸分子之间可产生强氢键作用,包括高强度的多位点常规氢键与p型氢键,导致PMAA/SiO2对阿魏酸有强吸附力,吸附容量达266 mg/g. 质子性溶剂甲醇中的溶剂竞争吸附作用使阿魏酸的吸附容量降低,升高温度吸附容量降低.     

Ordering of Polystyrene Nanoparticles on Substrates Pre-Coated with Different Polyelectrolyte Architectures

Adjusting the inter-particle distances in ordered nanoparticle arrays can create new nano-devices and is of increasing importance to a number of applications such as nanoelectronics and optical devices. The assembly of negatively charged polystyrene (PS) nanoparticles (NPs) on Poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) brushes, quaternized PDMAEMA brushes and Si/PEI/(PSS/PAH)₂, was studied using dip- and spin-coating techniques. By dip-coating, two dimensional (2-D), randomly distributed non-close packed particle arrays were assembled on Si/PEI/(PSS/PAH)₂ and PDMAEMA brushes. The inter-particle repulsion leads to lateral mobility of the particles on these surfaces. The 200 nm diameter PS NPs tended to an inter-particle distance of 350 to 400 nm (center to center). On quaternized PDMAEMA brushes, the strong attractive interaction between the NPs and the brush dominated, leading to clustering of the particles on the brush surface. Particle deposition using spin-coating at low spin rates resulted in hexagonal close-packed multilayer structures on Si/PEI/(PSS/PAH)₂. Close-packed assemblies with more pronounced defects are also observed on PDMAEMA brushes and QPDMAEMA brushes. In contrast, randomly distributed monolayer NP arrays were achieved at higher spin rates on all polyelectrolyte architectures. The area fraction of the particles decreased with increasing spin rate.     

微孔聚丙烯膜表面季铵化及其抗菌性能

为了赋予微孔聚丙烯膜(MPPM)抗菌能力,发展了一种有效的表面季铵化方法。基于紫外光引发丙烯酸的接枝聚合,通过碳二亚胺活化,将聚亚乙基亚胺(PEI)共价固定于MPPM表面,用环氧丙烷对PEI链上的伯胺和仲胺进行叔胺化,最后再和苄氯反应,成功地使MPPM表面季铵化。采用FTIR、XPS、荧光素二钠盐染色和水接触角对膜进行了表征。采用平板活菌计数法考察了季铵化膜对大肠杆菌和金黄色葡萄球菌的抗菌性能。结果显示,季铵化膜对大肠杆菌和金黄色葡萄球菌均具有强的抗菌活性;增加膜表面阳离子密度或延长接触时间,均能有效提高膜的抗菌能力。     

聚维酮碘在硅胶表面的固载化及其杀菌性能

将N-乙烯基吡咯烷酮(NVP)接枝聚合到硅胶表面,制得接枝微粒PVP/SiO2;使接枝微粒PVP/SiO2在乙醇溶液中与碘发生络合反应,形成水不溶的聚维酮碘PVP-I2/SiO2,即实现了聚维酮碘的固载化. 考察了各种因素对络合反应的影响规律,用红外光谱与化学分析法对功能微粒PVP-I2/SiO2的化学结构与组成进行了表征. 以大肠杆菌为致病菌体,采用平板活菌计数法研究了PVP-I2/SiO2的杀菌性能. 研究结果表明,PVP/SiO2与碘的络合反应的适宜温度为60℃,经12 h后达到络合平衡,络合度随溶液中碘浓度的增大而提高,最大约为0.16%(w). 固载化的功能微粒PVP-I2/SiO2具有很强的杀菌能力,在药剂量为5 g/L的条件下,与浓度为109 CFU/mL的菌悬液接触3 min,即可使杀菌率达100%;胞外DNA和RNA测定与TTC-脱氢酶活性测定结果验证了水不溶聚维酮碘PVP-I2/SiO2的杀菌机理.     

Polyethyleneimine‐grafted membranes for simultaneously adsorbing heavy metal ions and rejecting suspended particles in wastewater

Heavy metal ions (HMIs) in wastewater can be removed by polyethyleneimine (PEI) adsorption, however, it is difficult to recycle PEI macromolecules from their mixture with suspended particles in wastewater. A novel HMIs adsorption technique with renewable PEI‐grafted porous membranes was developed. PEI molecules were dispersed with high specific area and structured morphology, which allowed HMIs and suspended particles to be retained separately at different locations of the membrane, with the former adsorbed in matrix and the latter rejected on surface. The membranes with the optimized PEI loading ratio of 30 k wt % behaved excellently with microsphere rejection and Co(II) adsorption reaching 98.5% and 51.0 mg/g, respectively. They successfully decreased Co(II) concentration from 3.0 mg/L to the allowable discharge standard (0.5 mg/L), even with an enhanced flux of 6200 L/m²/h at 0.12 MPa under the cyclic tests. Overall, PEI‐grafted membrane adsorption is highly efficient for removing HMIs and suspended particles simultaneously from wastewater. © 2017 American Institute of Chemical Engineers AIChE J, 63: 4541–4548, 2017     

反应体系组成对纳米SiO_2/PS复合粒子粒径及分布的影响

研究了在纳米SiO2粒子表面的苯乙烯原位聚合反应中,反应体系的组成(单体、引发剂、稳定剂及纳米SiO2粒子用量)对纳米SiO2/PS复合粒子的形态、粒径大小及分布的影响。结果表明,当纳米SiO2粒子与单体质量比为5%,苯乙烯质量分数为25%,引发剂及稳定剂用量分别为单体用量(质量比)的0.15%和1.5%时,制备出的纳米SiO2/PS复合粒子呈球形,表面光滑无明显缺陷,颗粒之间分散性很好,粒径为0.923μm,分散系数为0.108。