低温等离子体对聚合物多孔膜的亲水化改性

综述了低温等离子体在聚合物多孔膜表面亲水化改性领域的研究与应用进展。在简要介绍等离子体技术的原理、方法的基础上,讨论了Ar、He、O2、N2、CO2、H2O、NH2和SO2等非反应性和反应性气体的等离子体表面处理,烷基醇、烷基胺、烯丙基醇和烯丙基胺等饱和及不饱和单体的等离子体沉积聚合,以及烯类单体的等离子体引发的接枝聚合等等离子体方法,对膜表面和膜孔壁的化学组成和形态结构、膜亲水性的获得及其时效性、膜水通量和蛋白质抗污染性等方面的影响。     

等离子体聚合和处理在聚合物改性中的应用

本文综述了等离子聚合和处理在聚合物改性中的应用，介绍并述评了其发展概况。并对高分子等离子体化学在分离膜、保护膜、电子材料、光学材料等领域中的最新应用进行了介绍。     

用低温等离子体处理方法改性高分子材料表面

综述了利用等离子体改性高分子材料表面的最新进展,其应用与机理。     

聚丙烯微孔膜的等离子体接枝聚合改性

利用拉伸时的晶型转变致孔特性,从β晶相聚丙烯经单向或双向拉伸制得了新型聚丙烯微孔膜、用等离子体接枝聚合技术接上了亲水性聚合物如聚丙烯酸、聚丙烯腈等。研究了等离子体处理时间、单体性质对得到的亲水膜的亲水性、离子/溶质渗透性的影响。发现接枝聚丙烯酸的双向拉伸膜对Na~+、Mg~(++),尿素有较大的渗透性,并具有优良的形状稳定性。     

商品聚氯乙烯膜的等离子体表面处理改性的研究

利用辉光放电技术,将C_2H_2/CO_2/H_2的等离子体聚合物沉积处理聚氯乙烯商品膜表面进行改性。用红外光声光谱和扫描电子显微镜分析观察了等离子体改性的聚氯乙烯膜的结构和表面形态。测量了改性膜的水接触角,计算了它们的表面自由能,界面自由能以及表面功,从而研究了改性膜的亲水性。同时,利用热重分析仪(TGA)研究了改性膜的热稳定性。     

XPS研究低温等离子体聚苯乙烯表面改性

用氮气、二氧化碳和空气等离子体技术处理聚苯乙烯表面 ,并用X光电子能谱 (XPS)测定了聚合物表面的元素组成 ,相对含量和表面功能团的类型 .结果表明 ,经过不同条件处理后的聚合物表面引入了含氮和含氧基团 ,这对改善材料的沾润性和粘着性将起着明显作用 ;另外 ,不同处理条件对PS表面的氮、氧含量有很大影响     

等离子体改性聚合物表面动力学的动态接触角法研究

不同聚合物经CF~4/CH~4等离子体处理后,在浸水过程中表面动力学衰减常数对温度通过Arrhenius关系作图,对于所研究的聚合物都有一个明显的转折点。转折点处的温度称作表面构型转变温度(T~s),大约为15℃,与表面邻近水的Drost-Hansen温度一致。T~s以上及以下的活化能数值较小,说明表面构型变化的本质可看作是由于基团的翻转运动,而不需要整个大分子或链段的迁移运动。在浸水过程中,接触角滞后Δθ在表面构型转变温度T~s附近有转变,并有极小值,此后随着温度的升高出现极大值,继续升高温度接触角滞后Δθ又反而下降。     

低温等离子体制备与改性纳米催化材料的研究进展

低温等离子体属于非热平衡等离子体,它具有较高的电子温度和较低的气体温度,是一种纳米催化剂制备与改性的新方法。 低温等离子体因其高效、环境友好、材料易实现功能化等特点在制备和改性纳米催化材料方面引起了广泛关注,在纳米催化材料的非常规制备、掺杂、缺陷和空位制造中展现了突出的优势,因而被广泛用于各类催化剂的制备与改性中。 本文主要综述了低温等离子体在氧还原(ORR)、氧析出(OER)、析氢(HER)和燃料氧化反应(FOR)催化剂制备与改性方面的研究进展,从不同角度阐述了上述各类催化剂性能改善的原因,并对低温等离子体在纳米催化剂制备与改性方面存在的成本相对较高、反应器放大、材料可控制备等挑战进行了总结,最后对等离子体制备与改性纳米催化剂的发展趋势进行了预测。     

低温等离子体对超高分子聚乙烯纤维表面改性研究

介绍了低温等离子放电技术的概念、原理、实施方法及其在超高分子量聚乙烯（UHMWPE）纤维表面改性方面的应用。综述了国内外低温等离子体对UHMWPE纤维表面改性的最新研究成果,阐述了气体等离子体种类、处理功率和处理时间等因素对UHMWPE纤维表面改性效果的影响机理,以及低温等离子设备对UHMWPE纤维表面改性连续化的初步...     

医用聚氯乙烯膜的等离子体表面改性

用两种不同气氛的辉光放电等离子体工艺对医用软质聚氯乙烯（ＰＶＣ）膜进行了表面改性研究。结果表明，聚合性气氛的等离子体改性效果明显优于非聚合性气氛。平整致密的聚合膜对ＰＶＣ增塑剂——邻苯二甲酸二辛酯的迁移和扩散起了阻挡作用，也使膜表面亲水性和表面张力极性成份增大，液固相界面张力减小，生物相容性得以改善。     

Novel AC and DC Non-Thermal Plasma Sources for Cold Surface Treatment of Polymer Films and Fabrics at Atmospheric Pressure

Novel types of non-thermal plasma sources at atmospheric pressure based on multi-pin DC (direct current) diffusive glow discharge and AC (alternative current) streamer barrier corona have been elaborated and tested successfully for cold surface treatment of polymer films [polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET),] and polyester fabric. Results on physical properties ofdischarges mentioned and output energy characteristics of new plasma sources as well as data on after-treatment changes in wettability of films and fabrics are presented. The main goal of this study was to find out the experimental conditions for gas discharge and surface processing to achieve a remarkable wettability change for a short treatment time.     

Aqueous Diphenyl Degradation Induced by Plasma with Glow Discharge Electrolysis

The degradation of aqueous phase diphenyl induced by plasma that was locally generated between an electrolytic solution and an anode tip is investigated. Results indicated that the degradation rate can be greatly increased by increasing the applied voltage. Faster removal rate can be achieved for a relatively higher alkalinity or acidity. Fe²⁺ has an evident catalytic effect on the diphenyl elimination, while the presence of n‐butanol inhibited the degradation. The major intermediate products of the degradation process were identified by HPLC analysis and a degradation pathway was proposed.     

等离子体辐照的聚乙烯表面接枝交联共聚合

聚合物利用低温等离子体预辐照进行表面接枝共聚合已有报道.此方法的优点是接枝层被限制在聚合物表面,辐照过程对基材本体性质无影响,且整个过程对环境无污染. 用等离子体使聚合物表面产生自由基,不需要表面具有不饱和键或特殊官能团,因而适用于任何聚合物,甚至于一些无机物如玻璃等.利用等离子辐照后暴露于空气的聚合物表面上生成的过氧自由基或过氧化物进行接枝反应,一般接枝量不大.本工作中,我们自己设计了反应器,以超高分子量聚乙烯(UHMWPE)为基材,以甲基丙烯酸甲酯(MMA)为接枝单体,在无氧条件下利用等离子体辐照产生的表面自由基进行了接枝聚合,产物接枝量高达10％.还用顺磁共振技术对表面自由基性质及其在接枝过程中的行为进行了跟踪研究.     

Plasma Induced Degradation of Azobenzene in Water

The degradation of azobenzene (AO) by a gaseous plasma is reported. The plasma was generated in a localized zone between an electrolytic solution and a tip of an anode in contact with the surface of solution by means of contact glow discharge electrolysis. There is an optimum pH for the degradation of AO. Iron (II) had a remarkable catalytic action on it. Furthermore, the degradation followed the first‐order kinetic law. Some of the intermediate products of the degradation process were detected by HPLC.     

冷等离子体作用下CH_4-CO_2转化制合成气

在常温常压条件下 ,利用电晕放电 ,使 CH4 - CO2 混合气转化生成合成气 .结果表明 ,该过程中 CH4 和 CO2 的转化率与反应体系能量密度、原料气配比和流速等有关 .在 0 .1MPa气压 ,能量密度为 10 50 k J/ mol(反应体系温度低于 50 0 K) ,n( CH4 )∶ n( CO2 ) =1∶ 2条件下 CH4 和 CO2 的转化率分别超过 60 %和 50 % ,超出了热力学平衡转化率的限制 .通过调配原料的配比 ,可以得到不同 n( H2 ) / n( CO)比值的产物 .对该体系的反应机理进行了探讨 .     

Direct Non-oxidative Methane Conversion by Non-thermal Plasma: Experimental Study

The direct non-oxidative conversion of methane to higher hydrocarbons in non-thermal plasma, namely dielectric barrier discharge and corona discharge, has been investigated experimentally at atmospheric pressure. In dielectric barrier discharge, the methane is mainly converted to ethane and propane with small amounts of unsaturated and higher hydrocarbons. While in corona discharge, methane was activated mainly to acetylene with small amount of other higher hydrocarbons. Decreasing the gas flow or increasing power input will improve the methane conversion and product yields. It is found that the methane conversion and main product yield against the input specific energy were special functions in both dielectric barrier discharge and corona discharge, independent of the reactor size, and whether fixing flow rate or power input and changing the power input or flow rate. The corona discharge is a promising alternative method for methane conversion to produce acetylene and hydrogen at low temperature.     

辉光放电电解等离子体处理制备铁基表面超疏水材料

利用辉光放电电解等离子体技术对铁基底表面进行活化,经硬脂酸修饰,得到铁基底超疏水性材料。 考察了放电电压、放电时间、Na2SO4浓度以及硬脂酸乙醇溶液浓度对铁基超疏水表面性能的影响。 用接触角仪、X射线光电子能谱、红外光谱和扫描电子显微镜测试技术对铁表面的浸润性、表面元素组成结构以及表面形貌进行了表征和分析。 结果表明,经修饰的铁基底表面具有良好的疏水性,其水接触角高达154°,滚动角小于5°,且具有良好的稳定性。     

Oxidative Degradation of Aqueous Cresols Induced by Gaseous Plasma with Contact Glow Discharge Electrolysis

The oxidative degradation of cresols smoothly proceeded toward inorganic end products when a gaseous plasma generated by means of dc glow discharge was sustained in contact with the surface of aqueous solution containing organic compounds. In order to get mechanistic insight, the monohydroxylation products from each isomeric cresol were closely examined as primary intermediates to reveal that the aromatic hydroxylation preferentially occurred at the position para to the hydroxyl group of each starting material. It was also established that the degradation of cresols strictly followed the first-order rate law. On the basis of the orientational analysis and the kinetical consideration including the effects of Fe ions added on the reaction rate, it was concluded that hydroxyl radical, which might result from the homolytic cleavage of water molecules by the action of plasma, was the most likely reagent responsible for the mineralization of cresols.     

Surface Modification of Textile Fibers and Cords by Plasma Polymerization

In this paper we report on the treatment of industrial fibers and cords by means of plasma polymerization techniques. Coatings of plasma-polymerized pyrrole or acetylene were deposited on aramid fibers, aramid cords and polyester cords. The equipment was a custom-built semi-continuous reactor operated on a pulsed DC glow discharge. The fibers and cords were tested for adhesion to various polymers such as tire cord skim stock rubber compounds and epoxy adhesives. Standard industrial pull-out force adhesion measurement techniques were used. The deposition conditions of the plasma polymer films were varied within wide limits. It was found that, in general, films deposited under low-power and high-pressure conditions performed better than films prepared under high-power and low-pressure conditions. For some systems pulsing of the discharge power improved the performance further. For all systems studied, the optimized plasma polymer surface modification outperformed current industrial standards. The plasma-polymerized coatings were characterized by various techniques and the excellent performance results are explained in a tentative model based on the molecular structure of the films. This structure was found to be strongly dependent on the discharge conditions.