塑料直接电镀与塑料电镀技术的应用现状

介绍了在塑料基体上直接电镀的三种主要形式之一：导电性高分子直接电镀,其基础是使用了导电性的高分子聚合物材料;并且综述了塑料电镀技术在各方面的应用及其现状。     

塑料基体直接电镀的前处理工艺

塑料基体直接电镀的工艺为:用含Pd2+离子的CrO3和H2SO4混合液进行粗化,使其表面获得均匀的粗糙度和改善后续活化工艺中钯的吸附效果。在还原工序中添加了一种特殊的表面活性剂,来增加钯的吸附。经过铜置换工序,Cu2+及其络合物在塑料表面移除了Sn2+,使得表面形成钯铜的导电膜,可以直接镀酸性铜。新型塑料电镀工艺不仅无需使用化学镀,而且操作更加容易,稳定性提高,废水处理简单,大大缩短了生产时间,生产中途无需更换挂具,生产率大大提高。     

三维电极反应器导电粒子去除水中4-氯酚的性能研究

采用涂覆法和浸渍法分别制备了以Pd、Ru、Sn为负载催化剂,以塑料填料和活性炭填料为载体的导电粒子,用于三维电极法催化降解4-氯酚模拟废水。结果表明:在相同处理条件下,塑料填料导电粒子对4-氯酚的去除效果优于活性炭填料导电粒子。2种导电粒子的重复使用性和再生性研究表明,塑料填料导电粒子可重复使用性更高,且再生的塑料填料导电粒子不影响其再次使用。     

TiCl_3/PdCl_2法活化多孔陶瓷基体制备透氢Pd膜

以TiCl3取代SnCl2作为敏化剂,考察TiCl3/PdCl2活化法对Pd膜制备及性能的影响。所制备Pd膜的表面与断面形貌采用SEM与金相显微镜表征,测试膜的透氢性、选择性以及高温稳定性,比较了TiCl3/PdCl2与SnCl2/PdCl22种活化方法对Pd沉积速率的影响。结果表明:TiCl3/PdCl2活化法同样能够在多孔陶瓷基体表面形成活性催化层,并最终成功获得高性能的Pd膜。相对而言,TiCl3/PdCl2活化法更有利于Pd膜的快速形成,而且彻底避免了Sn对Pd膜的污染,有望成为SnCl2/PdCl2活化法的一种理想替代方法。     

高导电性的塑料薄膜

最近,日本茨城电气通信研究所研制成功一种新型导电性塑料。这种塑料是在本来绝缘的塑料中掺入金属或碳而使其具有导电性的。其工艺是把属于一种导电性的高分子材料聚吡咯在缘绝性的塑料薄膜中以化学反应进行复合化,用这种方法就可以把广泛应用的聚氯乙烯薄膜或聚苯     

塑料电镀发展及其工艺

塑料电镀广泛用于工业生产,是在ABS(Acrylonitrile-Butadiene-Styrene)塑料问世以后.近几年来,国外除了在工艺上进行改革,研制浸蚀-活化一步法,实行连续自动化生产外,还致力于研究导电性树脂,塑料能直接电镀.目前日本塑料电镀中所用的塑料,ABS占90%左右,PP(聚丙烯)占5%左右,PPO(聚苯醚)占5%左右.我国塑料电镀的工业生产是在1966年以后,发展速度很快.塑料电镀产品广泛应用于电视机、收音机、电风扇、电子元件、家具、汽车和钮扣等各方面.并已经有了塑料电镀的自动化生产线.从工艺上讲,我国     

专利实例

镀前处理五则97301铜的化学机械抛光本专利介绍具有多层金属层的铜的化学抛光所采用的抛光液。该抛光液为悬浮固体的稀浆，其组成为AgNO32％～15％（体积），H2O2，H2O。美国专利US5354490（1993．3）97302催化处理溶液本专利介绍一种以Pd作为催化剂加到基体表面的工艺。该溶液含有Pd2＋离子和有机络合剂（含－COOH基和－OH基）而不含还原剂。将基体与该溶液接触后，以一定波长的光辐射，产生离子的光还原，从而将Pd金属涂覆于基体上。美国专利US5400656（1993．12）97303电镀前塑料表面的处理本专利介绍在塑料表面上进行电镀前的预…     

塑料电镀中的一步法表面敏化和活化处理

塑料电镀技术在近30年已发展成为一种有价值的技术。由于镀层与基体的结合力好,抗蚀性能比以钢铁为基体的镀层强,并且耐热、耐磨性能也能满足设计要求,因此,应用越来越广。选择符合标准的塑料（目前电镀所用的大多是电镀级ABS树脂）,按照规定的注塑方法加工成型,然后再依次进行表面机械粗化、化学粗化、敏化、活化、     

采用新型无锡活化工艺在γ-Al2O3粉体上化学镀钯的研究

采用一种新型无锡活化工艺,即利用乙二醇作还原剂直接使Pd2+被还原成Pd0而沉积在基体上,实现了对γ-Al2O3粉体的活化.将活化后的γ-Al2O3粉体加入到两种钯镀液中,成功实现了γ-Al2O3粉体上的化学镀钯.研究了活化的机理以及化学镀前后γ-Al2O3粉体结构与表面形貌的变化,结果表明通过新型化学镀方法制备出的镀钯粉体1-Pd/Al2O3中钯粒子的粒径在20-30nm,并且粒径大小分布均匀.新型无锡活化工艺与传统的化学镀活化工艺相比,活化过程中无锡离子干扰,并且活化在中性条件下进行,基体不受损坏.     

基于表面化学吸附的ABS塑料化学镀铜新工艺的研究

采用生物高聚物(壳聚糖薄膜)通过化学吸附将催化剂金属(Pd)固定在丙烯腈-丁二烯-苯乙烯(ABS)塑料基体上,实现了一种低成本、环保的ABS塑料表面活化新工艺。对预处理后的ABS薄膜进行X射线光电子能谱(XPS)分析,了解其反应机理。结果表明:化学吸附法相比传统的物理吸附法,提高了镀层与基体的结合强度,获得了致密且连续的Cu-P铜层结构。     

Nano-patterning of through-film conductivity in anisotropic amorphous carbon induced using conductive atomic force microscopy

Direct nanometer patterning of through-film electrical conductivity on carbon films is crucial in the development of carbon materials for nanotechnology. Typically, nanometer topographical surface modification can be created using scanning probe microscopy techniques producing surface artifacts which do not extend through the film. Here, we demonstrate the direct nano-patterning of through-film conductivity on highly oriented anisotropic carbon films by applying single voltage pulses (6 V) to a conductive atomic force tip in contact with the film. The thus induced conductivity is at least four orders of magnitude higher than that of the nominal area.     

高分子表面金属化技术

高分子表面金属化是对高分子材料表面进行改性处理使其具有良好物理性能、力学性能及金属光泽的表面技术,广泛应用于高分子导电、薄膜修饰、电磁屏蔽等领域。本文综述了高分子表面金属化的两大类技术方法,即干法镀膜和湿法镀膜。介绍了几种典型的表面处理技术,如真空镀膜、喷涂金属转移法、化学镀、化学还原金属化以及电镀,并总结了它们的技术特点以及在科学研究和工业生产应用中的难点。阐明了从传统电镀技术发展而来的高分子表面直接电镀工艺的优势,直接电镀工艺省去了电镀前的活化工序,缩短了工艺时间,避免了电镀前工艺对环境造成的污染,成为高分子表面金属化技术发展的新方向。     

酚醛塑料环保型电镀精饰新工艺

针对目前酚醛塑料无法直接电镀、无法规模化电镀及现有电镀工艺废水污染严重的现状,研究一种在酚醛塑料表面直接电镀的环保经济型新工艺。通过对导电涂层表面导电能力、沉积速率、镀液稳定性及结晶颗粒细致度的具体分析、实验对比,提出在酚醛塑料表面喷涂以次纳米级铜粉为导电金属的导电金属漆层,采用以次亚磷酸钠作为还原剂的化学镀铜工艺,在涂层表面镀覆一层薄铜。该工艺对酚醛塑料表面可直接进行电镀,在实现重金属等污染物零排放的同时大幅降低了生产成本。     

Electrical conductivity of carbon black filled polymers—effects of morphology and processing

This paper discusses the relation of the morphology of conductive carbon black and its critical volume fraction, ?_c, required to achieve semiconductor property. We also discuss the influence of processing on the electrical conductivity of polymer composites. An equation based on the crowding factor of concentrated suspension rheology and Janzen's particle contacts percolation is proposed to describe the relationship between ?_c, and the maximum packing fraction of conductive fillers. The relationship could explain the influence of particle morphology on conductivity and the conductivity difference in the high shear and low shear region of a processed polymer composite part.     

Conductive coating films based on low density In2O3 powders and polymer latexes

Several kinds of conductive coating films were prepared from a low-density indium(III) oxide powder (which was employed because it provides a much higher volume for the same weight) and polymer latexes. The low-density In₂O₃, which is an electrically conductive pigment, was prepared by pyrolysis followed by the combustion of water-swellable polymer microspheres imbibed with In(NO₃)₃, the precursor of In₂O₃. Either acrylamide/N,N'-methylenebisacrylamide or poly(vinylalcohol)/glutaricdialdehyde was used to generate spherical hydrogel particles. The polymer latexes with which the In₂O₃ was mixed had a soft core and a hard shell structure to ensure that the coating film has suitable mechanical properties in addition to conductivity. Acrylonitrile/butadiene/styrene copolymer ABS or acrylonitrile/butylacrylate/styrene copolymer ABAS latexes were used as binders for the conductive pigment. The powder coating followed by hot pressing, the water-borne coating consisting of low-density In₂O₃ and polymer latexes followed by curing, or the colloidal dispersion coating was used to deposit flexible conductive coating films on polyester sheets. The conductive pigment density and the polymer latexes' size and flowability are the factors that affect the characteristics of the film. We found that the colloidal suspension coating procedure based on ABAS latexes achieves better electrical and mechanical properties for the coating films. © 1996 John Wiley & Sons, Inc.     

The effect of chemical exposure on the EMI shielding of conductive plastics

The electrical properties of a number of filled plastics were examined after subjecting the materials to exposure to isopropyl alcohol, a 25°C detergent/water solution, an 80°C detergent/water solution, and at various chemical plant sites. Compositions which contained metal fillers maintained their conductivity only when a high temperature thermally stable polymer was used as the polymer matrix, while compositions which are made conductive through a carbon filler network maintained their conductivity under most of the exposure conditions examined even when low temperature polymers were used as matrices.     

Conductivity enhancement of carbon nanotube and nanofiber-based polymer nanocomposites by melt annealing

The addition of multi-walled carbon nanotubes (MWCNTs) or carbon nanofibers (CNFs) to polymeric melts offers a convenient route to obtain highly conductive plastics. However, when these materials are melt processed, their conductivity can be lost. Here, it is shown that conductivities can be recovered through melt annealing at temperatures above the polymer's glass transition temperature (T_g). We demonstrate these results for both MWCNT and CNF-based composites in polystyrene (PS). The mechanism behind the conductivity increase is elucidated through modeling. It involves a transition from aligned, unconnected particles prior to annealing to an interconnected network after annealing through viscoelastic relaxation of the polymer. Such re-arrangement is directly visualized for the case of the CNF-based composites using confocal microscopy. The annealing-induced increase in particle connectivity is also reflected in dynamic rheological measurements on both MWCNT and CNF composites as an increase in their elastic moduli at low frequencies.     

炭黑在高分子聚合物中的导电性研究

以EVA为高分子聚合物，采用不同级别的导电炭黑，研究了导电炭黑填充高分子聚合物的导电性，讨论了不同级别和不同用量的导电炭黑在聚合物中的分散性，以及对高分子聚合物导电性的影响。实验结果表明，导电炭黑高分子聚合物的导电性主要取决于不同级别的导电炭黑的表面性和结构等特性、炭黑的不同用量以及导电炭黑的聚集体在高分子聚合物的分散程度。     

The effect of thermal stresses on the EMI (electromagnetic interference) shielding of conductive plastics

The electrical properties of a number of filled and coated plastics were examined after subjecting the materials to rigorous thermal cycling between −20 and 80°C. Filled compounds that obtained their conductivity through the addition of carbon based conductive fillers maintained their conductivity throughout the thermal cycling. Compositions which contained metal fillers were able to maintain their conductivity only when a high temperature thermally stable polymer was used as the polymer matrix. Plaques coated by a zinc arc spray or with acrylic paints containing graphite, silver, and nickel particles were unaffected by thermal cycling. Plaques coated with an acrylic paint containing copper particles lost most of their conductivity during the changes in sample temperature.