聚二甲基硅氧烷－氯磺化聚乙烯共混涂膜表面润湿性与表面结构的研究

研究了α，ω－二羟基聚二甲基硅氧烷（ＨＴＰＤＭＳ）－氯磺化聚乙烯（ＣＳＰ）非均相共混涂膜表面润湿性与表面结构的关系，发现膜表面疏水性随ＣＳＰ含量增加而出现突变点。ＸＰＳ分析证明，这是由于氯元素在表成含量呈突变性。阐明均一的疏水性共混涂膜形成的条件。     

含氮硅烷对聚二甲基硅氧烷涂膜表面疏水性的影响

将含氮硅烷与正硅酸乙酯进行对比，研究了它们对端羟基聚二甲基硅氧烷（ＨＴＰＤＭＳ）缩合固化形成的涂膜表面疏水性的影响，发现固化剂ＮＨ２（ＣＨ２）３Ｓｉ（ＯＣ２Ｈ）３使涂膜疏水性明显下降．用ＥＳＣＡ和相差显微镜等方法证明了这种现象是由于ＮＨ２（ＣＨ２）３Ｓｉ（ＯＣ２Ｈ５）３自身固化产生的分相性引起的．     

接枝共聚物氯化聚乙烯－苯乙烯对聚苯乙烯的共混改性

用氯化聚乙烯接枝苯乙烯共聚物（ＣＰＥ－ｇ－Ｓｔ）和氯比聚乙烯（ＣＰＥ）对聚苯乙烯（ＰＳ）进行共混改性．当ＣＰＥ含量为２５％时，用ＣＰＥ－ｇ－Ｓｔ改性的共混物的冲击强度为１８．５ｋＪ·ｍ￣（－２），是用ＣＰＥ改性的共混物冲击强度的２．１倍；其拉伸强度不低于３４ＭＰａ．     

（PSF—PDMS—PHS）n／PSF共混物的相容性及表面组成

利用ＤＳＣ、ＤＭＡ、ＴＥＭ和ＸＰＳ对［ＰＳＦ－ＰＤＭＳ－ＰＨＳ］ｎ／ＰＳＦ共混物的相容性及表面组成进行了研究．结果表明，ＰＤＭＳ在共混物表面的富集与ＰＳＦ均聚物和［ＰＳＦ－ＰＤＭＳ－ＰＨＳ］ｎ中硬段的相容性有关；ＰＤＭＳ在相容的共混物体系表面的富集与对应的多嵌段共聚物组成基本相近；不相容共混物体系表面ＰＤＭＳ的富集程度相对较高，当共混物本体中有机硅含量从１％增至５％，表面层ＰＤＭＳ的含量迅速增加，可达到嵌段共聚物中ＰＤＭＳ的含量．     

接枝共聚物氯化聚乙烯—苯乙烯对聚苯乙烯的共混改性

用氯化聚乙烯接枝苯乙烯共聚物（ＣＰＥ－ｇ－Ｓｔ）和氯化聚乙烯（ＣＰＥ）对聚苯乙烯（ＰＳ）进行共混改性。当ＣＰＥ含量为２５％时，用ＣＰＥ－ｇＳｔ改性的共混物的冲击强度为１８．５ｋＪ．ｍ＾－＾２，是用ＣＰＥ改性的共混物冲击强度的２．１倍；其拉伸强度不低于３４ＭＰａ。     

引入离子基团改善聚苯乙烯和热致液晶聚合物的相容性 Ⅰ热性能和形态

ＤＳＣ和ＳＥＭ研究结果表明聚苯乙烯（ＰＳ）与一种热致液晶聚合物（ＬＣＰ）（ＰＨＢ／ＰＥＴ（６０／４０）共聚酯）完全不相容．共混体系具有与组分无关的Ｔｇ，并且表现出明显的两相结构．将ＰＳ进行化学改性（引入磺酸基团）制备成磺化聚苯乙烯（ＳＰＳ），随中和盐离子的变化有：酸式、Ｌｉ、Ｎａ、Ｚｎ和Ｍｎ盐五种形式．用ＤＳＣ和ＳＥＭ对ＬＣＰ与ＳＰＳ共混物的热性能和形态进行了分析和表征．共混体系有一个与组成相关，且明显低于纯ＳＰＳ的Ｔｇ．这表明了ＰＳ与ＬＣＰ的相容性因为磺酸基团的引入而得到了改善．同时用Ｆｏｘ方程计算了ＬＣＰ的Ｔｇ．当ＳＰＳ含量较低时（不大于５０％）在各个共混体系中，所估算的ＬＣＰ的Ｔｇ相互吻合．表明共混体系满足Ｆｏｘ方程的前提条件，即ＬＣＰ与ＳＰＳ形成相容体系．当ＳＰＳ含量较低时（２５％），ＬＣＰ／ＳＰＳ的共混物为较均一体系，断面光滑；而ＳＰＳ含量较高时，在脆断面可以观察到纳米级的颗粒．电子能谱分析证明了这些颗粒是ＳＰＳ负离子的聚集体．     

羧化聚苯醚／聚（苯乙烯—乙烯吡啶）共混相容性

用ＤＳＣ、ＤＭＡ研究了羧化聚苯醚（ＣＰＰＯ）／聚（苯乙烯－乙烯吡啶）（ＰＳＶＰ）共混体系的相容性，结果表明，与ＣＰＰＯ／ＰＳ体系相比，乙烯吡啶基的引入大大提高了共混相容性．这主要是由于ＣＰＰＯ中的羧基与ＰＳＶＰ中的吡啶基之间通过质子转移形成的正负离子间的相互作用，推动了两组分分子的均匀混合．     

酞侧基聚芳醚砜／聚苯硫醚共混物的形态与力学性能

酞侧基聚芳醚砜（ＰＥＳ－Ｃ）与聚苯硫醚（ＰＰＳ）具有部分相容性，虽然ＰＰＳ的强度和韧性均低于ＰＥＳ－，但ＰＰＳ含量为２％～１０％的ＰＥＳ－Ｃ／ＰＰＳ共混物在保持ＰＥＳ－Ｃ原有强度，断裂伸长率的同时，模量略增，冲击强度有很大幅度提高，熔融指数亦蛔。     

溴化十二烷基吡啶的吸附和表面胶团化对二氧化硅悬浮液稳定性的影响

研究了阳离子表面活性剂溴化十二烷基吡啶（ＤＰＢ）的吸附和表面胶团化对二氧化硅（ＣＡＢ－Ｏ－ＳＩＬ）悬浮液稳定性的影响，以及加入电解质的效应．结果表明：ＤＰＢ在ＣＡＢ－Ｏ－ＳＩＬ上的吸附等温线呈双平台（或ＬＳ）型，溴化钠（０．１ｍｏｌ／Ｌ）的存在使吸附等温线向低浓区移动，第二平台的饱和吸附量增大，但基本不影响第一平台的吸附量，这些结果都与涉及形成表面胶团的二步吸附模型相符．当ＤＰＢ浓度很低时，ＣＡＢ－Ｏ－ＳＩＬ悬浮液的稳定性随ＤＰＢ浓度的增大而下降；当ＤＰＢ浓度增至ｓｍｃ（临界表面胶团浓度）附近时，悬浮液稳定性急剧提高．ＮａＢｒ的存在，并不影响上述悬浮液稳定性规律．利用表面活性剂的二步吸附和颗粒相互作用模型，并结合ＤＰＢ吸附等温线的研究结果，可以合理地解释ＣＡＢ－Ｏ－ＳＩＬ悬浮液稳定性的实验结果．     

等离子体改性聚丙烯纤维表面的XPS研究

用等离子体技术处理了聚丙烯纤维表面．用Ｘ－射线光电子能谱（ＸＰＳ）研究了聚合物表面的元素组成、相对含量的变化、表面官能团的类型．采用曲线拟合分峰技术对谱图进行数学处理，结果表明：尽管处理气氛不同，聚丙烯纤维表面除含有Ｃ—Ｈ和Ｃ＝Ｃ键外，还引入了Ｏ、Ｎ元素．形成活性基团：－ＯＨ、＞Ｃ＝Ｏ、－ＣＯＯＨ、－ＮＨ２和－ＣＯＮＨ２等，提高了聚合物表面活性。     

聚苯硫醚超疏水复合涂层的制备与性能

利用工业原料聚苯硫醚微粉和疏水性二氧化硅纳米粉末,采用喷涂法在瓷砖表面制备了疏水复合涂层.研究了热处理温度、组分配比对涂层表面形貌、粗糙度和接触角的影响,发现随着热处理温度升高,涂层表面粗糙度增大,随着疏水性二氧化硅含量的增加,由于表面聚集的疏水性二氧化硅增多,涂层疏水性增强,在热处理温度为280℃、疏水性二氧化硅与聚苯硫醚质量比为1∶1时,可获得超疏水涂层,涂层的接触角大于150°,滚落角小于4°,pH值为1～14的水溶液在其表面都具有很高的接触角.超疏水涂层具有良好的自清洁效果,并且经落沙法实验测定,超疏水涂层耐刮伤性能良好.     

Preparation and characterization of controlled heparin release waterborne polyurethane coating systems

In this study, to improve hemocompatibility of biomedical materials, a waterborne polyurethane (WPU)/heparin release coating system (WPU/heparin) is fabricated via simply blending biodegradable WPU emulsions with heparin aqueous solutions. The surface compositions and hydrophilicity of these WPU/heparin blend coatings are characterized by attenuated total reflectance infrared spectroscopy (ATR-FTIR) and water contact angle measurements. These WPU/heparin blend coatings show effectively controlled release of heparin, as determined by the toluidine blue method. Furthermore, the biocompatibility and anticoagulant activity of these blend coatings are evaluated based on the protein adsorption, platelet adhesion, activated partial thromboplastin time (APTT), thrombin time (TT), hemolysis, and cytotoxicity. The results indicate that better hemocompatibility and cytocompatilibity are obtained due to blending heparin into this waterborne polyurethane. Thus, the WPU/heparin blend coating system is expected to be valuable for various biomedical applications.     

Hydrophobic Silica Sol Coatings on Textiles—the Influence of Solvent and Sol Concentration

Hydrophobic silica sol coatings on textiles were investigated with respect to the influence of the solvents and the concentration of the sol. For this purpose, two silica sols, prepared with the hydrophobic additives octyltriethoxysilane and perfluoroctyltriethoxysilane were diluted by different solvents: water, ethanol and aceton.In case of using pure water for dilution, the hydrophobicity of coated textiles decreases drastically with increasing dilution of the applied sol. For coatings on polyester fabrics or mixed fabrics made from polyester and cotton, the use of the organic solvents ethanol or aceton leads to significant hydrophobicity even in case of strong dilution down to a sol concentration < 1%. The hydrophobic effect of coated polyamide textile is less. The reason for different hydrophobicity of coated textiles resulting from the use of water instead of organic solvents is explained by different surface morphologies of the coatings deposited on the textile fibres, as observed by REM. In case of using organic solvents the coatings contain a more flat morphology which covers the fibres completely. In contrast, sols with higher water content lead to less adhesive coatings with crack formation.The use of a combination of water with less inflammable organic solvents such as di(propylene glycol) n-propyl ether (Dowanol^TM DPnP) in hydrophobic silica sols yields textile coatings with good hydrophobicity, even in case of low sol concentration. For practical application of textile coatings, especially silica sols with high water content are of interest, due to less risk of inflammation and lower ecological impact. Therefore, the use of water diluted hydrophobic silica sols with small amounts of DPnP offers a chance for textile refinement by the sol–gel technique.     

二氧化硅／环氧树脂复合涂层的制备及其疏水性能

采用喷涂技术,在马口铁表面喷涂环氧树脂和二氧化硅复合涂层,研究了二氧化硅的含量对表面疏水性的影响,复合涂层的疏水性随二氧化硅含量的增加而增加．当二氧化硅质量分数增大到40％时,所制备的复合涂层与水的接触角约为141°且具有较小的滚动角．     

Synthesis of biocompatible hydrophobic silica-gelatin nano-hybrid by sol-gel process

Silica-biopolymer hybrid has been synthesised using colloidal silica as the precursor for silica and gelatin as the biopolymer counterpart. The surface modification of the hybrid material has been done with methyltrimethoxysilane leading to the formation of biocompatible hydrophobic silica-gelatin hybrid. Here we are reporting hydrophobic silica-gelatin hybrid and coating precursor for the first time. The hybrid gel has been evaluated for chemical modification, thermal degradation, hydrophobicity, particle size, transparency under the UV-visible region and morphology. FTIR spectroscopy has been used to verify the presence of CH(3) groups which introduce hydrophobicity to the SiO2-MTMS-gelatin hybrids. The hydrophobic property has also been tailored by varying the concentration of methyltrimethoxysilane. Contact angle by Wilhelmy plate method of transparent hydrophobic silica-gelatin coatings has been found to be as high as approximately 95 degrees . Oxidation of the organic group which induces the hydrophobic character occurs at 530 degrees C which indicates that the surface hydrophobicity is retained up to that temperature. Optical transmittance of SiO2-MTMS-gelatin hybrid coatings on glass substrates has been found to be close to 100% which will enable the hybrid for possible optical applications and also for preparation of transparent biocompatible hydrophobic coatings on biological substrates such as leather.     

EFFECT OF COMPOSITION AND PROCESSING CONDITION ON MICROSTRUCTURAL PROPERTIES AND DURABILITY OF FLUOROPOLYMER/ACRYLIC BLENDS

 Fluoropolymer blends have been widely used as binders for exterior coatings because of their excellent resistance to ultra-violet (UV) radiation as well as to many corrosive chemical agents. It is known that the fluorinated component usually has a lower glass transition temperature and easily crystallizes in the final structure depending upon the blend composition and sample annealing condition. We investigated the effect of blend composition and annealing process (slow and fast cooling) on the surface morphology and microstructure a poly(vinylidene fluoride)/poly(methyl methacrylate) (PVDF/PMMA) blend before and after UV exposure. Surface and subsurface microstructures were studied by atomic force microscopy (AFM) and laser scanning confocal microscopy (LSCM). Bulk microstructure of PVDF-coatings before and after UV exposure were characterized using small angle neutron and light scattering. Higher PVDF content and a slow cooling process result in larger spherulite crystallite structure and rougher surface morphology. Significant ordering in the spherulite crystallite structure has been observed on the surface and the bulk films after UV exposure.     

Tailoring of interface of polypropylene/polystyrene/carbon nanofibre composites by polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene

Mechanical and physical properties of polypropylene (PP)/polystyrene (PS) blend, PP/PS/polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (SEBS) ternary blend and their composites with carbon nanofibers (CNF) were investigated. Composites of ternary blend exhibited superior properties compared to those of binary blends. Mechanical performance of nanocomposites was intimately related to their phase morphology. PP/PS/SEBS/0.1 wt% CNF hybrid composites exhibited excellent impact strength (Four-fold increase compared to PP/PS blend) and ductility (12-fold increase in elongation at break, with respect to PP/PS blend). Moreover, these composites displayed good tensile strength and modulus (15% increase in Young's modulus, compared to PP/PS/SEBS blend) and are suitable for various end-use applications including automobile applications. Although crystallinity of PP phase is decreased by the incorporation of CNF, thermal stability of the composites remained almost unaffected. Contact angle measurements revealed that ternary composites exhibited maximum hydrophobicity.     

EFFECT OF COMPOSITION AND PROCESSING CONDITION ON MICROSTRUCTURAL PROPERTIES AND DURABILITY OF FLUOROPOLYMER/ACRYLIC BLENDS

Fluoropolymer blends have been widely used as binders for exterior coatings because of their excellent resistance to ultra-violet (UV) radiation as well as to many corrosive chemical agents.It is known that the fluorinated component usually has a lower glass transition temperature and easily crystallizes in the final structure depending upon the blend composition and sample annealing condition.We investigated the effect of blend composition and annealing process (slow and fast cooling) on the surface mor...