膜

摘要\n对膜法从水溶液中萃取溶解甲烷进行了参数研究。对基于橡胶聚合物(如聚二甲基硅氧烷( PDMS )和聚乙醚-b-酰胺( PEBA ) )的非多孔膜和疏水微孔膜(如聚四氟乙烯( PTFE ) )进行了评价。通过模型建立和参数分析，评价了进料侧液相浓差极化对水溶液中溶解甲烷萃取的影响。研究表明，当液体边界层中浓差极化可忽略不计时，微孔PTFE膜在甲烷通量(比非微孔膜高3 ~ 5个数量级)和湿渗透流中甲烷浓度( ~ 97mol . %与PTFE膜相比)方面均优于非微孔膜。但在正常水动力条件下，进料侧浓差极化的影响不可忽略，甲烷抽提通量受到明显折中( PTFE和PDMS膜的通量降低90 %，PEBA膜的通量降低50 %，渗透压力为10 k Pa )。研究发现，增大渗透压力会以降低通量为代价，减缓浓差极化。适当控制进料液的水动力条件，以增强膜表面附近的传质，似乎是脱气应用的一条实际途径。

摘要( # br )聚二甲基硅氧烷( PDMS )是微流体、传感器技术等诸多领域中常用的材料。尽管PDMS的用途非常广泛，但仍然需要更简单、重复性更低的PDMS薄膜制备方法。在本工作中我们提出了一种晶圆制备技术，该技术允许多个PDMS铸件在衬底上进行，无需再处理。将聚苯乙烯薄膜旋涂在作为PDMS防粘层的晶片上。在PDMS制备前后对涂层进行了表征，整个加工过程保持不变。进一步，在涂复的圆片上制备的PDMS薄膜与较厚的PDMS基底结合，形成膜器件。该装置被演示为光学压力传感器。

Abstract\n\t\t\t\t\n\t\t\t\t\tThe syntheses of siloxane-grafted poly(amide-imide) and polyamide were carried out by a macromonomer method, in order to develop a highly permeable and durable membrane material for pervaporation. A novel compound, 3,5-bis(4-aminophenoxy)benzyloxypropyl-terminated polydimethylsiloxane (\n\t\t\t\t\t\tBAPB-\n\t\t\t\t\t\tPDMS), was synthesized as a macromonomer.

Fabrication and Characteristics of Thermopneumatic-Actuated Polydimethylsiloxane Microvalvemicrovalve;thermopneumatic-actuation;PDMS;ITO heater;membrane;A normally open thermopneumaticc-actuated microvalve has been fabricated and their properties are investigated. The advantages of the proposed microvalve are of the low cost fabrication process and the transparent optical property using polydimethylsiloxane (PDMS) and indium tin oxide (ITO) glass. The fabricated microvalves with in-channel configuration are easily integrated with other microfluidic devices on the same substrate.

Pervaporative Recovery of Bio-butanol through Dense- and Composite-type PDMS Membranesbio-Butanol;polydimethylsiolxane;pervaporation;composite;membrane;recovery;Bio-butanol recovery by pervaporation was performed with dense and composite polydimethylsiloxane (PDMS) membranes. The pervaporative behavior of the membranes was investigated as a function of operation temperature $(20{\\sim}40^{\\circ}C)$ and membrane thickness $(100{\\sim}1{\\mu}m)$ using a series of aqueous BtOH model solutions $(1{\\sim}5wt%)$.

Preparation and Permeation Characteristics of PDMS-b-PMMA Copolymer MembranePDMS-b-PMMA;membrane;permeability;selectivity;ATRP;In this research, polydimethylsiloxane-polymethylmethacrylate (PDMS-PMMA) block copolymer was synthesized from polydimethylsiloxane (PDMS) and methylmethacrylate (MMA) monomer using atom transfer radical polymerization (ATRP). The synthesis characterization of the PDMS-b-PMMA copolymer membrane was carried out by a FT-IR, $^1H$-NMR, GPC and DSC.

Permeation Behavior of Olefin/Nitrogen Gases through Siloxane based Polymeric MembranesPolydimethylsiloxane;Olefin;Nitrogen;Off-gas;Membrane;For the olefin recovery from polyolefin off-gas, the permeation behaviors of olefins and nitrogen were investigated through three kinds of PDMS membranes - cross-linked PDMS membranes, a polysiloxaneimide membrane, and oligo-PDMS modified PDMS membranes.

Blend membranes of synthesized polyurethane based on toluene diisocyanate (TDI), polydimethylsiloxane (PDMS) and polytetramethylene glycol (PTMG) with polyamide12-b-PTMG were prepared by solution casting technique. The synthesized polyurethane-polydimethylsiloxane and PU-PDMS/polyamide12-b-PTMG blend membranes were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM).

摘要\n膜分离的主要挑战之一是塑化效应降低选择性。为了更好地理解这一现象，了解混合物各组分的吸附行为是必要的。为此，成功设计了吸附式热虹吸仪( STA )，并进行了气体吸附测试。与实际其他方法相比，STA方法的主要优点之一是利用热虹吸管记录压力衰减情况，保证顶空浓度均匀。平衡条件在取样过程中不受干扰，允许在吸附实验结束时保留准确数据。为了验证新体系的有效性，通过STA等实验技术获得了纯CO2和CH4以及CO2 / CH4 ( 50 / 50 )混合物在聚二甲基硅氧烷( PDMS )中的吸附、扩散和渗透系数，与文献数据吻合较好。

聚合物膜在气体分离过程中遇到的一个最关键的问题是气体渗透性和选择性之间的权衡效应。本工作旨在开发一种简单而有效的涂层技术，对常用的聚砜( PSF )中空纤维膜进行表面改性，以解决CO2 / CH4和O2 / N2分离的权衡效应。本研究通过在聚醚嵌段酰胺( Pebax )制备的选择性涂层中加入氧化石墨烯( GO )纳米片，制备了多层包复PSF中空纤维。为了防止Pebax涂层溶液渗入膜基片，在基片和Pebax层之间形成了聚二甲基硅氧烷( PDMS )的沟槽层。然后考察GO负载量( 0.0 ~ 1.0wt % )对Pebax层性能和膜性能的影响。XPS数据清楚地显示了膜选择性层中GO的存在，GO掺入量越高检测到的碳的sp2杂化状态越大。在膜层形貌方面，增加GO用量只影响膜表面粗糙度，而不改变整个膜层厚度。结果表明，在Pebax膜层中添加0.8wt % GO可以得到性能最好的多层膜，与未添加GO的膜相比，CO2 / CH4和O2 / N2气对选择性分别提高了56.1 %和20.9 %。这种改进是由于选择性层中曲折路径增加，相对于较小的气体分子( CO2和O2 )，对较大的气体分子( CH4和N2 )产生了更高的阻力。