微孔聚丙烯膜表面胺基化修饰

发展了一种氨基接枝密度和分布可控的微孔聚丙烯膜(MPPM)表面修饰方法。首先通过紫外光接枝聚合法,在MPPM上接枝聚丙烯酸甲酯(PMA);然后通过丙烯酸甲酯和乙二胺的酰胺化缩合和Michael加成交替反应,将氨基可控地引入到MPPM表面。采用FTIR、XPS和ESEM对氨基化膜表面的化学组成及物理形态进行了表征;考察了氨基化膜的表面亲水性及渗透性能。结果表明,氨基化膜表面亲水性显著改善,吸水量可达(1 311.29±97.56)μg/cm2,为未修饰MPPM的145倍;制得的氨基化膜具有良好的水通量和金属离子渗透性能。     

聚丙烯微孔膜表面AgCl修饰层的构建及其抗菌性

通过多巴胺氧化聚合修饰及交替浸渍技术在聚丙烯微孔膜(MPPM)表面构建了Ag Cl修饰层。采用FTIR、XPS对构建过程膜表面的化学变化进行了分析;采用SEM-EDX对膜表面形态及Ag Cl分布进行了考察;通过表面水接触角及水通量的测定分析了膜的亲水性;采用平板活菌计数法评价了膜对大肠杆菌及金黄色葡萄球菌的抗菌能力。结果表明,制得的修饰膜具有强的抗菌能力和良好的表面亲水性,其对大肠杆菌和金黄色葡萄球菌的抗菌率分别达99.2%和100%。     

PVA表面交联制备亲水性PP微孔膜及其性能研究

利用聚乙烯醇(PVA)的亲水性和交联性,实现了聚丙烯(PP)微孔膜的亲水化改性。实验考察了PVA浓度,交联时间等因素对改性PP膜性能的影响。采用ATR-FTIR、SEM、接触角和纯水通量等表征和测试方法对改性前后PP膜的性能给予了评价。结果表明,由于PVA的强亲水性,使得改性后的PP膜的亲水性能明显提高,接触角由110°(未改性PP膜)降低至55°,初始纯水通量最高可达425 kg/(m2h)。由于PVA的交联性质使得其稳定地固定于PP膜表面,使PP膜具有更持久的亲水性,PP-cl-PVA膜经反复清洗后依然可保持高亲水性。经改性后,PP膜的通量恢复率提高了14%,说明PP-cl-PVA膜的抗污性能得到显著提高。     

聚丙烯微孔膜的研究进展

介绍了由熔融纺丝-冷却拉伸法和热致相分离法制备聚丙烯微孔膜的原理和过程。对当前膜研究领域的热点即膜的亲水化改性研究进行了重点评述,包括暂时性改性和永久性改性。阐述了各种改性方法的特点,着重讨论了亲水化改性对膜性能如膜的微孔孔径、孔隙率、透水量等的影响,强调膜表面亲水性的提高可改善膜的耐生物污染性。指出聚丙烯微孔膜的应用领域和发展前景。     

荷电微孔滤膜及其吸附性能的研究

本文研究了以天然多糖为荷电剂,用浸涂法制备的荷电微孔滤膜的吸附性能,探讨了制膜工艺及操作条件,如溶液组分,温度及ｐＨ值等吸附性能的影响,为荷电微孔滤膜的使用提供依据。     

聚丙烯微孔膜的亲水改性研究进展

聚丙烯微孔膜的强疏水性导致在膜分离过程中驱动力高和易污染,需要亲水化改性.亲水改性方法主要有共混法、表面吸附法、表面接枝法等。目前主要是对聚丙烯微孔膜表面进行改性,但表面改性容易对膜的微孔造成影响。共混法是最有效和应用前景的方法,是以后聚丙烯微孔膜亲水改性的研究重点。     

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。     

聚丙烯微孔膜高能电子束辐照改性及其性能研究

采用高能电子束辐照的方法在聚丙烯微孔膜的表面接枝丙烯酸锂,研究不同的辐照剂量对聚丙烯微孔膜表面接枝丙烯酸锂的接枝率的影响,并对辐照接枝后的聚丙烯微孔膜的结构和性能进行了研究。红外光谱测试结果表明:通过高能电子束辐照,聚丙烯微孔膜的表面能够成功地接枝上丙烯酸锂;表面水接触角测试结果表明,经辐照接枝丙烯酸锂后,聚丙烯微孔膜的表面水接触角减小,表面极性增加,表面亲水性得到提高;SEM观察结果表明,辐照后聚丙烯微孔膜的孔径减小;DSC测试结果表明:辐照后聚丙烯微孔膜的结晶峰温度向高温方向移动,结晶能力得到提高,结晶更加完善。     

微孔聚丙烯膜表面壳聚糖季铵盐的共价修饰及其抗菌性能

为了赋予微孔聚丙烯膜（MPPM）抗菌能力,增强其抗污染性能,本文通过丙烯酸的光引发接枝聚合、壳聚糖与聚丙烯酸的酰胺化反应、壳聚糖胺基与2,3-环氧丙基三甲基氯化铵的开环加成,成功地在MPPM膜表面通过共价修饰技术构建了壳聚糖季铵盐修饰层。构建过程通过FTIR、XPS和荧光素二钠盐染色分析得到了证实。静态水接触角和吸水量实验结果表明,制得的修饰膜具有优异的表面润湿性和吸水性,吸水量可达11.23mg/cm²,为未修饰MPPM的1123倍。以大肠杆菌和金黄色葡萄球菌为代表,采用平板活菌计数法考察了修饰膜的抗菌性能和抗菌稳定性。研究结果表明,修饰膜具有良好的抗菌活性,对大肠杆菌的抗菌率可达98%,对金黄色葡萄球菌的抗菌率可达100%,且抗菌效果稳定,在水处理领域具有潜在的应用前景。     

聚丙烯膜表面磷脂自组装/交联改性及其表面性能

发展了一种基于分子自组装/交联的聚丙烯微孔膜(PPMM)表面改性方法,以含不饱和长烷基链的两亲性天然卵磷脂为改性剂,首先通过分子自组装在PPMM表面形成类磷脂组装层,再采用紫外线原位聚合交联方法在PPMM表面构建稳定的类磷脂仿生修饰层,进而赋予PPMM表面优异的亲水性和生物相容性。分别采用FTIR/ATR和XPS分析确证了改性前后膜表面基团及化学成分的变化。通过水接触角测定、荧光标记蛋白质吸附和酶联免疫吸附(ELISA)实验,考察了类磷脂仿生修饰前后膜表面亲水性和抗蛋白质吸附性能,发现类磷脂仿生修饰后PPMM表面水接触角由130°下降至30°,抗蛋白质吸附性能也得到明显改善;自组装/交联改性PPMM经多次水洗后仍能保持良好的亲水性和抗蛋白质吸附性能,表明膜表面所形成的类磷脂仿生修饰层具有良好的稳定性。     

聚丙烯微孔膜研究进展

聚丙烯（PP）是一种价格低廉的塑料，是目前最主要的制备高分子微孔膜的材料之一。笔者综述了近年来PP微孔膜制备方法的研究进展，重点介绍了熔纺拉伸法（MSCS）、热致相分离法（TIPS）、共混拉伸法、熔融烧结法等PP微孔膜的常用制备方法，并对相关的影响因素进行了讨论。     

聚丙烯微孔膜的表面矿化修饰及其亲水性能

为了改善聚丙烯微孔膜(MPPM)的表面亲水性,通过组合多巴胺氧化聚合和交替浸渍矿化修饰技术,在MPPM表面构建了均匀的CaCO₃矿物层,实现了利用CaCO₃矿物对膜表面进行亲水化修饰的目的。采用FTIR、XPS、ESEM、EDX和水接触角对矿化膜表面进行了相应的表征。考察了溶液浓度、浸渍循环次数及聚多巴胺涂覆率等对CaCO₃矿化率的影响。结果证实,CaCO₃矿物均匀地负载在MPPM表面,膜的亲水性因CaCO₃固有的润湿性而明显改善。纯水通量测试结果表明,矿化膜具有强的水渗透能力,纯水通量大(高达6450 L·m^-2·h^-1),渗透阻力小,施加0.01 MPa的外压,水即可透过膜。油水乳液分离研究发现,矿化膜能有效地分离一定范围的油水乳液,水通量大(> 1800 L·m^-2·h^-1),且膜容易用水清洗,展现出理想的油水乳液分离应用前景。     

Preparation and adsorption performances of novel negatively charged hybrid materials

A series of novel negatively charged hybrid materials were prepared via sol–gel process and a subsequent epoxide ring‐opening reaction. The coupling reaction was conducted between 3‐glycidoxypropyltrimethoxysilane (GPTMS) and tetraethoxysilane (TEOS), which was confirmed by FTIR spectra. TGA, and DrTGA analyses showed that their thermal stabilities were higher and the optimal molar ratio of GPTMS and TEOS was equal to 1 : 1. The ion‐exchange capacities (IECs) exhibited that they were related to the amount of anionic groups in the hybrid materials, indicating that the negatively charged properties of the hybrid materials could be artificially controlled via the adjustment of silica in these charged hybrid materials. The adsorption properties for Pb²⁺ and Cu²⁺ ions revealed that these hybrid materials were able to absorb heavy metal ions, suggesting that they have potential applications in the separation and recovery of environmentally hazardous substances. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Vacuum membrane distillation simulation of desalination using polypropylene hydrophobic microporous membrane

Numerical simulation is an effective method to get the optimal operating parameters in the chemical engineering process. In this work, the transport mechanism of vacuum membrane distillation (VMD) process was simulated and predicted by mathematical model, which was established based on the convective heat transfer coefficient, and 0.5M aqueous NaCl solution was concentrated with isotactic polypropylene (iPP) hydrophobic microporous membrane prepared via thermally induced phase separation (TIPS) in the VMD process. The as‐presented mathematical model simulated the effects of different operating parameters on the VMD performances for aqueous NaCl solution, such as feed temperature, feed flow rate, absolute pressure of membrane permeate side, temperature coefficient, membrane thickness, and porosity. A comparison between experimental data and simulated data was also considered to verify the proposed mathematical model. Additionally, the salt rejection of aqueous NaCl solution production water in VMD was higher than 99.9%. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41632.     

荷电微孔滤膜对水中达旦黄吸附性能的研究

论述了荷电微孔滤膜对水中负电颜料达旦黄的吸附性能。实验证明,水的pH值在2．0－9．0之间,膜对达旦黄的吸附性能不受pH值的影响,但当pH值大于9．0时,其吸附性能减弱。文中氯化钠不影响膜的吸附性能。一般条件下,孔径为0．2μm的荷电微孔滤膜对达旦黄的吸附容量为10mg/cm^3。这表明荷电微孔滤膜在工业废水处理中对负电颜料的分离有着广阔的应用前景。     

Study of structure and properties of polypropylene microporous membrane by hot stretching

The polypropylene (PP) microporous membrane is prepared by only hot stretching of annealed PP film under different stretching rate and temperature. The structure and properties are compared with those by cold and hot stretching. The results show that apparent connecting bridges are observed on the surface of final microporous membrane only by hot stretching. With increasing stretching rate and decreasing stretching temperature, the pore size decreases and the air permeability becomes worse. The membrane only by hot stretching under 50 mm/min shows better lamellae separation, whereas under 10 mm/min the membrane gives lowest Gurley value. Compared with cold and hot stretching under the same stretching rate and whole stretching ratio, the membrane stretched only by hot stretching shows longer connecting bridges length, higher porosity and lower Gurley value. During only hot stretching, first the tie chains in the amorphous region are stretched. Then the combination of crystalline main lamellae and crystalline part formed during annealing is stretched and converted to connecting bridges. Through the control of stretching temperature and rate, PP microporous membrane with better permeability property can be obtained by only hot stretching, where room-temperature stretching is not needed. The obtained membrane can be used in Li-ion battery field as a separator, where the air permeability is an important technical parameter to characterize the Li-ion penetration ability through the separator.