高阻隔PVA涂布液的制备及性能

用自制改性剂通过溶液共混法制得高阻隔聚乙烯醇(PVA)涂布液,对涂布液黏度、吸水性、与基材的附着力及复合薄膜的阻隔性能进行了测试.结果表明,与未改性PVA涂布液相比,通过改性能有效减小PVA涂布液随时间和温度变化黏度增大的弊端;改性PVA涂布液与基材具有良好的附着力,可直接在聚对苯二甲酸乙二醇酯(PET)、双向拉伸聚丙烯(BOPP)、聚乙烯(PE)等薄膜表面涂覆;改性涂布液的吸湿率比纯PVA的小;改性PVA复合薄膜阻隔性能优良.     

五层共挤阻隔薄膜的结构、性能、工艺及表征

介绍了以聚乙烯、聚丙烯、尼龙6、乙烯-乙烯醇共聚物四种聚合物原料作为多层共挤复合膜的材料进行挤出成型制备高阻隔性的薄膜,其中以PA6和EVOH作为阻隔薄膜的阻隔层材料,将聚乙烯作制备阻隔薄膜的热封层材料。分别通过热重分析、流变性能测试详细讨论了各种聚合物原料的热稳定性、热流变性能等,并在此基础上探讨了五层共挤流延膜的加工工艺,而后又对制备得到的六种五层共挤流延膜的力学性能及阻隔性能进行了详细表征。     

提高HDPE阻隔性能的方法

提高高密度聚乙烯(HDPE)对气体、水蒸气及一些化学溶剂阻隔性能的主要方法是将其与高阻隔材料或无机纳米粒子共混,通过控制加工工艺改变HDPE分子取向或加入成核剂改善结晶形态与分布,对HDPE制品表面化学处理等.其中,与高阻隔材料共混比较常见,可将对油渗透率降低98％之多,在汽车油箱上有很重要的应用.其他方法可以提高对氧...     

PET瓶的等离子处理技术——ACTIS

一、ACTIS技术原理 ACTIS技术是法国西得乐公司开发的、利用等离子技术在PET瓶内壁上,涂布一层碳氢阻隔层制备高阻隔性塑料瓶的一种新方法。 ACTIS法将气态的乙炔导入PET瓶中,通过微波处理器将乙炔激化,使之呈等离子状态,等离子态的颗粒撞击在瓶壁上能量骤然消失,在壁上形成一层极薄而致密的固态涂层(高度氢化的无定型碳涂层),涂层的厚度不到200A,一只容量为500ml的PET瓶的涂层,仅8～9毫克,但却具有极佳的阻隔性能。     

高阻隔聚酯专用料成功为食品瓶助力

辽阳石化公司研究院采用纳米复合方法在聚酯合成过程中加入经高分子改性的纳米溶胶,使其均匀分散在聚酯高分子链间,有效阻隔气体渗透,制得的高阻隔聚酯阻隔性能突出,是普通聚酯阻隔性的两倍。使用该技术生产的高阻隔聚酯切片在制瓶时操作简单,便于控制,不需要特别精密、复杂的注塑模具,可以在普通注塑——制瓶联合设备上直接生产单层、透明的高阻隔聚酯啤酒瓶,有效降低生产成本。     

辽阳石化研制成功高阻隔聚酯专用料

辽阳石化研究院采用纳米复合方法,在聚酯合成过程中加入经高分子改性的纳米溶胶,使其均匀分散在聚酯高分子链间,有效阻隔气体渗透,制得的高阻隔聚酯阻隔性能突出,是普通聚酯阻隔性的两倍。使用该技术生产的高阻隔聚酯切片在制瓶时操作简单,便于控制,不需要特别精密、复杂的注塑模具,可以在普通注塑-制瓶联合设备上直接生产单层、透明的高阻隔聚酯啤酒瓶,有效降低生产成本。     

尼龙的改性剂和高阻隔性树脂—EVOH

EVOH是世界上最新奇的树脂，它既是尼龙的相容剂，改性剂又是高阻隔性树脂，使用EVOH可以生产出PA/EVOH/PE改性料，既是最好的阻隔材料，双是尼龙和聚乙烯的改性剂，值得大力推广。     

吹塑工艺对改性共聚尼龙/高密度聚乙烯中空吹塑瓶阻隔性能的影响

将由乙烯-丙烯酸酯-马来酸酐共聚物(CP)与共聚尼龙(PA-54)在双螺杆挤出机中反应共混制得的改性共聚尼龙(MCOPA)与高密度聚乙烯(HDPE)通过层状共混工艺制备高阻隔性中空吹塑瓶。研究表明,吹塑工艺对阻隔瓶的阻隔性能具有很大的影响。     

高阻隔高分子包装材料的发展现状

综述了目前常用高阻隔性高分子材料,指出了它们的优缺点,介绍了目前主要的阻隔技术以及高阻隔性高分子材料的应用现状。另外,探讨了当今几种新型高分子材料阻隔技术的优缺点,并对阻隔性高分子材料的发展趋势进行了展望。     

纳米片层填充型高阻隔性复合薄膜研究进展

聚合物包装材料在易变质产品领域的应用受到很大的限制,提高其气体阻隔性能成为研究热点。纳米片层填充法能够有效地利用"多路径效应"和"可渗透面积减少效应"提高聚合物包装材料的气体阻隔性能。纳米片层的填充使气体在聚合物中的扩散系数和溶解度系数下降,从而降低气体渗透系数,提高聚合物的气体阻隔性能。常见的纳米片层包括蒙脱土和石墨烯(或氧化石墨烯)。制备纳米片层填充型高阻隔复合薄膜的方法有2种:调整加工外场来调控纳米片层在聚合物基体中的取向程度;对纳米片层表面基团功能化来提高填料与基体的界面结合作用。今后的研究应致力于使用可生物降解的绿色材料制备高阻隔性聚合物包装薄膜。     

高分子膜材料的研究概况

介绍高分子膜材料的分类和研究方法,着重从高分子膜的性能、成膜及改性方法、新型膜材料几方面综述高分子膜材料的研究进展情况,同时概要叙述高分子膜材料的应用及今后的发展远景。     

Inorganic Layers on Polymeric Films – Influence of Defects and Morphology on Barrier Properties

Flexible polymeric films are not only widely used in conventional packaging as substitute for glass and aluminum foil packaging but are also proposed as encapsulation for novel products, like flexible solar cells or organic light‐emitting devices. The two essential properties of the polymeric packaging are flexibility and good permeation barrier properties against gases and vapors. This article deals with vacuum web coating as a common way of increasing barrier properties of polymeric films and the problems related to this procedure. Defects caused by particles and surface imperfections are found to dominate the permeation rate for such coated polymeric films. Atomic force microscopy, electron and also optical microscopy was used for analysis of the coating layer. Three‐dimensional numerical simulations were performed for modeling of the influence of defect size, spacing and film thickness. Results of numerical modeling and of many practical experiments show that the permeability is almost independent of the substrate film thickness when a critical thickness is exceeded. In most cases the defects can be treated as independent of each other. The gas permeability of vacuum web‐coated polymeric films can be quantitatively predicted by a simple formula. For gases, like oxygen, it is shown that a statistic analysis of the defect sizes by optical microscopy is sufficient. For water vapor transmission, however, the structure of the coating layer itself has also to be taken into account.     

Prediction of Release Characteristics of Film‐Coated Urea from Structure Characterization Data of the Film

An efficient method for the prediction of the release characteristics of film‐coated urea from its film structure is proposed. A model spray‐coating apparatus was built to prepare a plane film to directly measure the film permeability coefficients by simulating the characteristics of randomness, intermittence and multiple layers of the coating, and eliminating particle collision effects. From analysis, the spray‐coated film structure can be modeled as comprising a dense structure and a defect structure. Both structures contributed to the penetration flux and the apparent permeability coefficients of the film for water and urea diffusion. The permeability coefficients of the plane films were calculated from the film structure model, and were shown to be close to the measured values.     

碳酸盐岩潜山储层渗透率解释方法探讨

在双重孔隙结构的碳酸盐岩裂缝性地层中,渗透率为岩块渗透率和裂缝渗透率的总和,通常裂缝渗透率特别高,而岩块渗透率比较低。复杂岩性裂缝性潜山油气藏渗透率取决于岩石孔隙空间的连通性,而与岩石孔隙度之间不一定成正比关系,裂缝孔隙度很小,但裂缝孔隙连通性比较好,它的渗透率就比较高,岩块孔隙度虽然比裂缝孔隙度大,但它的孔隙连通性差,因此岩块渗透率比较低。     

我国农膜技术的发展方向

对我国目前农膜的现状作了简要介绍,详细介绍了降解地膜,功能性棚膜的研究进展及我国农膜的发展趋势。提出我国应当积极推广应用和研究开发光生物降解地膜和完全生物降解地膜,同时也应努力研究开发光生态棚膜和现代化光生态覆盖材料。     

高聚物薄膜的气体渗透性的研究——Ⅰ.气体渗透性的测定和表征

本文应用自制CS—135型渗透仪和渗透池,对聚酯薄膜等的气体渗透性进行测定,考察测定操作条件对测定结果的影响、同时对高聚物薄膜的气体渗透性问题和表征作了讨论。     

复合聚烯烃土工膜的研制

介绍采用挤出片熔融复合的有增强线网的无纺织物土工膜、纺织织物复合土工膜和防老化复合土工膜，研究了膜结构和增强网对机械性能的影响及膜的耐老化性能。结果表明，按拉伸强度一般编织织物复合土工膜＞无纺织物复合土工膜＞土工膜，按伸长率一般土工膜＞无纺织物复合土工膜＞编织织物复合土工膜。无纺织物复合土工膜具有较好的排水性能，可通过增加一个增强线网提高拉伸强度和降低伸长率。在纺丝、拉丝和挤出片材前加防老化母料，可提高土工膜的耐老化性，由测试结果表明，采用该所的防老化ＰＰ，人工加速老化性能达到２００ｈ，拉伸强度保持率７５．５％，３００ｈ达６８．２％，２００ｈ的人工加速老化相当于２年的自然气候曝晒试验。     

The Experimental Observation and Modelling of Film Thinning and Film Retraction during the Interfacial Coalescence of Biodiesel and Glycerol Droplets

This paper is concerned with the way interfacial coalescence of a single drop of biodiesel or glycerol occurs at a glycerol/biodiesel interface. Two stages of interfacial coalescence were studied: the thinning of the trapped liquid film between the rising or falling droplet and bulk fluid interface, and the retraction of the film after the film had ruptured. Unexpectedly, the thinning time for the high viscosity glycerol film around a rising biodiesel droplet was found to be much shorter than that for a low viscosity biodiesel film around a sedimenting glycerol droplet. Squeeze flow modelling showed that the film of glycerol around a biodiesel droplet was bounded by relatively inviscid biodiesel and therefore flowed with high slip at its interfaces, resulting in rapid film thinning. The biodiesel film around a glycerol droplet was bounded by highly viscous glycerol and flowed with little slip at the interfaces, resulting in slower film thinning. After rupture, film retraction was found to be much faster for biodiesel droplets than for glycerol droplets. The drag exerted by the fluid surrounding the film was found to control the retraction kinetics. The results are of particular relevance to the separation of glycerol from biodiesel and of general relevance to coalescence kinetics for immiscible drops at an interface.     

应用多孔阳极氧化电流—时间曲线比较壁垒膜厚

在有壁垒膜存在的表面,多孔膜的生长在氧化初期受到延迟阻碍,这一现象在直流恒压多孔阳极氧化电流一时间曲线上反映出来。电流达到稳态氧化的时间愈长,壁垒膜愈厚。文中应用此法判断了0.5MH_3BO_3介质的pH值、温度对壁垒阳极氧化膜厚的影响,并应用记录同一介质环境壁垒恒流阳极氧化的槽压一时间曲线得到验证。     

CPP薄膜中成核剂用量对其性能的影响

研究成核剂A3用量对CPP薄膜光学性能、机械性能、热封性能和摩擦系数的影响,结果表明,添加0．6％－1．2％质量比A3成核剂,能使雾度在4％以下,对透明性基本无影响,能同时提高拉伸强度和断裂伸长率,热封强度提高10％左右,起始热封温度保持127℃,热粘强度无变化,摩擦系数先升后降,动摩擦系数比静摩擦系数下降更快。