反相气体色谱(IGC)在碳素材料研制中的应用

本文整理了反相气体色谱(IGC)在研究碳素材料固体表面性质方面的一些应用,以表面吸附热力学理论为轴线,介绍了IGC的基本原理,汇总了几种石墨和碳纤维的表面自由能(△AG°_A)、分子摩尔热焓(△H°_A)、摩尔熵(△S°_A)等热力学参数的测定结果,兼论了参数变化规律及IGC在碳素材料科学领域里的发展远景。     

用反相色谱法研究玻璃纤维表面性能

普通气相色谱法是以研究对象作为流动相的,而反相色谱法(IGC)则是以所研究的对象为固定相,惰性气体为流动相,通过测定挥发性的探针分子在两相之间的相互作用来了解固定相的各种性能。IGC法自60年代以来,在聚合物物理性能的研究中得到了广泛的应用,如用来测定聚合物的热转变,研究聚合物的结晶和高分子溶液热力学性能等。但用反相色     

用反气相色谱法研究聚合物的老化 Ⅰ.三种抗氧剂在顺丁生胶中的效能 摘要

反气相色谱法(简称IGC)是1966年J、C、Petersen等人提出来的。至今国内外许多工作者利用IGC研究聚合物的性质,得到了满意的结果。然而关于用IGC研究聚合物老化的工作,在文献中很少报道。本工作试图用IGC,观察探针分子的比保留体积随顺丁生胶在色谱柱中老化时间的变化,考     

固体聚合物的表面张力研究

由倾斜法及静滴法测定了聚合物纤维及板材的浸润临界表面张力.应用S.Wu调和平均法测算其表面能及应用李联欢公式由聚合物本体性能Tg计算其表面能,结果表明测算的结果与实验值基本上一致,说明计算的方法是可行的.     

聚合物基超疏水涂层的制备及应用进展(1)

简要综述了超疏水表面的疏水机制及聚合物基超疏水涂层的基本情况(包括常用材料、制备方法及应用),重点阐述了聚合物基超疏水涂层的制备方法(如模板法、相分离法、刻蚀法和聚合物/无机纳米粒子复合法等)及其在自清洁、油水分离、抗冰冻和抗菌等领域的研究进展和存在的问题。最后对聚合物基超疏水涂层的应用前景进行了展望。     

聚合物基超疏水涂层的制备及应用进展(2)

简要综述了超疏水表面的疏水机制及聚合物基超疏水涂层的基本情况(包括常用材料、制备方法及应用),重点阐述了聚合物基超疏水涂层的制备方法(如模板法、相分离法、刻蚀法和聚合物/无机纳米粒子复合法等)及其在自清洁、油水分离、抗冰冻和抗菌等领域的研究进展和存在的问题。最后对聚合物基超疏水涂层的应用前景进行了展望。     

超细粉体表面包覆技术综述

通过超细粉体的表面包覆以改善粉体的分散性及其表面性质,已经成为超细粉体制备和应用的关键技术。综述了超细粉体的表面包覆方法,包括机械化学法、气相沉积法、聚合物包裹法、液相化学法及微胶囊化法等,主要介绍了每种方法的基本原理及应用。     

羟基磷灰石复合材料与骨组织工程研究进展

羟基磷灰石(HA)是一种仿生无机生物材料,是骨骼的主要无机物组分,具有骨细胞诱导性以及生物活性,但HA力学性能和韧性差,利用聚合物对HA进行改性是克服HA缺点的有效方法。综述了原位聚合法、溶液分散法、共沉淀法、表面包覆法和表面接枝法等制备聚合物基HA复合材料的方法及在骨组织工程中的应用研究进展。     

原子转移自由基方法合成聚合物刷的研究进展

从聚合物刷基底的选择和聚合方法的优化两方面介绍了原子转移自由基聚合方法合成聚合物刷的研究进展,讨论了聚合物刷在图案化材料表面、提高材料表面的生物相容性及其它方面的应用情况,并对其前景进行了展望.     

反相气相色谱法研究等规聚丁烯-1的晶型变化及结晶动力学

等规聚丁烯-1具有四种晶型,并且常常是几种晶型混合存在,它与聚合物的制备和结晶条件有关。聚丁烯-1的结晶度及其晶型转变,可以用密度法、红外光谱法及X射线衍射等方法研究,通常用膨胀计方法研究其结晶动力学。本文是用反相气相色谱法(IGC)测定等规聚丁烯-1的结     

Multiparameter solution model and evaluation of polymer–polymer miscibility using inverse gas chromatography data

Inverse gas chromatography (IGC) has been widely used to determine the Flory–Huggins parameters, χ, between solutes (probes) and polymers. This study correlated the Flory–Huggins parameter data using a multiparameter model, which included dispersion, polarity, acidity, and basicity components. The parameters of poly(ε‐caprolactone) (PCL) and polyepichlorohydrin (PECH) were calculated from IGC data using a series of probes. The parameters of the polymers were used to evaluate mutual miscibility between PCL and PECH. The results predicted miscibility in agreement with the conclusion of an IGC study using blends of PCL and PECH. A method to estimate the confidence interval of polymer parameters was proposed. The anomalous solubility parameter of polymer mixtures previously reported was also explained using this model. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Inverse gas chromatography, surface properties, and interactions among components of paint formulations

Inverse gas chromatography (IGC) was applied to the surface characterization of polymers and pigments used in the formulation of protective coatings. IGC measurements over a significant temperature range provided surface energy and acid-base interaction parameters for these materials. Two sets of IGC data were obtained: (1) the quantity of vapor used to probe solid surfaces was extremely small, with results describing the properties of the most energetic surface sites; and (2) finite concentrations of vapor probes were used, with results describing the average properties of surface sites. A comparison of the two sets gave information on the heterogeneity of sites on the polymer and pigment surfaces. Heterogeneity parameters were defined for sites interacting through dispersion forces as well as for those able to interact as acids and bases. The present work reinforces the usefulness of surface characterizations by IGC by showing that the stability of pigments dispersed in the polymer vehicles was a function of the acid-base interaction between polymer-pigment pairs. Dept. of Chemical Engineering, Ecole Polytechnique, P.O. Box 6079, Stn. Centre Ville, Montreal, Que. H3C 3A7, Canada. 19-17 Ikeda Nakamachi, Neyagawa, Osaka 572, Japan.     

Inverse gas chromatographic study of polymer blend interactions and their temperature dependence

The temperature dependence of the thermodynamic interactions in blends of polypropylene and a fluorochemical was studied by inverse gas chromatography (IGC). A modified procedure has been proposed to evaluate the effective surface composition in polyblends. This shows that the low surface energy component preferentially concentrates in the surface region of blends. Moreover, the new procedure greatly reduces the probe-to-probe variation of χ₂₃, a problem frequently encountered in thermodynamic applications of the IGC method. As a result, IGC may now be used with increased confidence for the determination of interaction thermodynamics in polymer systems over broad temperature ranges. © 1992 John Wiley & Sons, Inc.     

Chromatographic estimation of filler surface energies and correlation with photodegradation of kaolin filled polyethylene

Inverse gas chromatography (IGC) has been used to investigate the surface properties of two calcined kaolins and of polyethylene composites containing calcined kaolin. The results reveal differences in the two kaolins that were not found in XPS spectra nor in their influence on the melting behaviour of the polymer. The kaolin that had a markedly higher surface energy and stronger Lewis acid behaviour was found to shower greater photooxidative degradation in accelerated weathering tests. This novel application of IGC derived surface characterisation of solids further extends the usefulness of the method in this type of work.     

Inverse gas chromatography study of poly(dimethyl siloxane)—liquid crystal mixtures

Inverse gas chromatographic (IGC) measurements are reported for 17 hydrocarbon probes on a low molar mass hexyloxycyanobiphenyl liquid crystal (LC) mixed with linear poly(dimethyl siloxane) (PDMS). The retention properties are compared with a side-chain liquid crystalline bearing the same mesogen. The results show that the retention of the LC polymer is significantly different from a mixture with the same composition. DSC and IGC values for the transition temperatures indicate that PDMS does not blend with HCB although some interactions, characterised by a Flory-Huggins interaction parameter, were seen and some effect on the liquid crystalline behaviour was noted. The usefulness and limitations of the IGC technique for characterising this type of polymer-LC system are discussed.     

PC与PCCD相容性的研究

用溶解度参数法包括三维溶解度参数基团贡献计算法、反气相色谱法以及差示扫描量热(DSC)法研究了聚碳酸酯(PC)和聚(1,4-环己烷二甲酸-1,4-环己烷二甲醇)酯(PCCD)的相客性.研究了色散、极性和氢键作用力对PC和PCCD相容性的影响.用基团贡献计算法得到PC和PCCD的三维溶解度参数非常接近,并且每一维度(即色...     

Use of Flory–Huggins parameters in the characterization of polymer–filler compositions

Any quantitative information on the strength of interactions between an inorganic filler and polymer is substantial for the future application of the composite. The magnitude of adhesion of two phases may be deduced from results collected by various experimental techniques. A Flory–Huggins interaction parameter (χ₂₃^′) was earlier successfully used in the characterization of polymer blends. We propose to express the magnitude of modified filler/polymer interactions by using χ₂₃^′. It was calculated from retention data of test solutes during an inverse gas chromatography (IGC) experiment. IGC is an extension of conventional gas chromatography in which a nonvolatile material to be investigated is immobilized on a column. Parameters determined during IGC experiments may be successfully used in the characterization of polymers and their blends, composites, fillers, and other materials and the quantification of the interactions between the components of polymer mixtures, including the interactions between polymeric components and filler surfaces. Here this method is applied to the characterization of a series of poly(ether urethane)/modified carbonate–silicate filler systems containing different amounts of a filler (5, 10, and 20 wt %). The possibilities and limitations of the IGC method are shown. The usefulness of some methods for minimizing the Δχ effect (the dependence of χ₂₃^′ on the type of test solute) is examined and discussed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Surface properties of some styrene/vinyl pyridine diblock polymers adsorbed on rutile

Inverse gas chromatography (IGC) has been applied for the surface characterization of styrene-4-vinyl pyridine (S-4VP) diblock polymers of varying composition and of two rutile pigments. The latter were used as adsorbents for the polymers. Dispersion surface energies and acid-base interaction parameters were obtained from the IGC data. These show that the adsorbed layers form interphases where the local composition varies with the mass of adsorbed polymer and also with the acid-base interaction between rutile and the polymer. The results may be rationalized by suggesting that the more basic 4VP moiety preferentially orients to the acidic rutile surfaces, leaving surface compositions enriched in the less basic polystyrene (PS), which also has a lower surface energy. The effect was more pronounced when the strength of acid-base forces at the interface was increased. The experimental findings also permit the calculation of thicknesses for the adsorbed interphases. These were found to be in the range 30-90 nm, depending on the mass of adsorbed polymer and on its acid-base interaction with the adsorbing pigment surface.     

Probe selection and description in IGC: A nontrivial factor

Inverse gas chromatography (IGC) has found many uses in the characterization of polymer surfaces and their interaction capabilities. The IGC method relies on the selection of vapors with which to probe polymer surfaces. Problems attached to the volatile phase in IGC are considered. One of these is the temperature dependence of the probe molecule dimensions. Experimental work shows that correcting for this temperature dependence is recommended when IGC work is carried out at temperatures removed from the ambient by more than 30°C. A second problem area is a possible variation in the orientation of adsorbed probe molecules. The variable orientation of linear alkane probe molecules on a polystyrene substrate is demonstrated, as is an orientational degree of freedom when diols of varying chain lengths are adsorbed on polymeric as well as on inorganic substrates. A conclusion reached from the experiments of this work is that acid–base parameters generated by the IGC method have relative but not necessarily absolute significance. Further, the orientation of polar probe molecules is dependent on the force field generated by the underlying substrate, which may be characterized by its total surface free energy. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2323–2330, 2003     

反相气相色谱法测定溶液在高分子中的无限稀释活度系数

1 INTRODUCTI0NDue to its short experimental time,little sampleneeded,suitable for broad temperature range,inversegas chromatography(IGC)has been widely used tomeasure variety of properties of polymer systems,suchas the infinite diluted activity coefficients of solvent inpolymer,the glass transition temperature of polymerand the surface properties of polymer,etc.Those