Control of the Sorption Properties and Wettability of a Nonwoven Polypropylene Material by Direct Gas Fluorination

The effect of direct gas fluorination on the surface properties of a nonwoven polypropylene material was studied. Direct gas fluorination with mixtures of different compositions allows directional variation of the surface properties of the nonwoven polypropylene material. The surface becomes more hydrophobic when using a mixture of fluorine and nitrogen but less hydrophobic when using a mixture of fluorine, oxygen, and nitrogen. The modification leads to changes in the chemical composition of the surface and in the roughness of the material. The nonwoven polypropylene materials thus obtained exhibit increased sorption capacity for spent oil or water, respectively. Variation of the properties of the nonwoven polypropylene material allows expansion of its applications.

     

高温弱还原气氛下煤灰中矿物质的定量研究

利用X射线衍射(XRD)研究了1 100-1 500℃条件下弱还原性气氛下胜利褐煤和高平无烟煤煤灰中矿物质的变化,利用Siroquant定量软件计算了高温灰样中矿物质和无定形相的含量,结合化学成分分析,利用差减法计算了煤灰中无定形相的化学组成。结果表明,利用XRD、Siroquant软件并结合化学成分分析,可以对煤灰中的矿物质及无定形相进行定量分析,并可获得不同温度下无定形相的化学组成变化。不同温度范围内煤灰中无定形相的形态不同,当温度低于1 100℃时,煤灰中无定形相主要是未结晶或结晶度较差的氧化物,而随着温度的升高,矿物质发生熔融并形成了玻璃态物质,此时的无定形相则是以熔融的硅酸盐和硅铝酸盐为主。煤灰的硅铝比越低,高温下越容易生成莫来石。     

Blends of the β-modification of polypropylene

Preparation, crystallization and melting characteristics of blends of β-nucleated isotactic polypropylene with different elastomers and polyethylenes were studied. Blends of β-polypropylene can be prepared if the polymer additive is amorphous or has negligible α-nucleating effect during the crystallization of polypropylene.     

Non-destructive and in situ identification of rice paper, seals and pigments by FT-IR and XRD spectroscopy

This paper studied the chemical characteristics of rice paper, pigments and seals on Chinese calligraphies and traditional Chinese paintings. The techniques used here were Fourier transform infrared (FT-IR) spectroscopy and X-ray diffraction (XRD). FT-IR allows good identification of the substances present in pigments and inkpads and differentiates each era of rice paper. This can be the base of estimating the age of rice paper. Different crystalline phases can be identified by XRD, which is further evidence to separate different kinds of pigments or inkpads. Both of these methods were non-destructive in situ analysis and can be used in the identification in calligraphies and traditional Chinese paintings. These results confirmed that the applied techniques are relatively quicker and more reliable than traditional approaches authenticated by years of experience.     

聚丙烯纤维的X衍射曲线的计算分峰法

本文改进了 Hindeleh等的聚合物非晶态X衍射的表征函数,建立了用于研究聚丙烯纤维结构的计算分峰法。实践表明,它能够成功地应用于同时含有α晶态与非晶态或急冷晶态与非晶态等各种类型的聚丙烯纤维的结构研究。     

Succinyl fluorescein grafted atactic polypropylene as an interface modifier in polypropylene/talc composites: a thermal study under dynamic conditions

The subject of this work is the thermal behaviour of polypropylene/talc composites whose interface has been modified by atactic polypropylenes containing different numbers of succinyl fluorescein grafted groups. The interface modifiers used here were previously obtained in our laboratories by a two-step chemical modification of the melt of a by-product (atactic polypropylene) of industrial polymerisation reactors. The variations in interface activity caused by replacing a small amount of the polypropylene matrix in the composite by succinyl fluorescein grafted atactic polypropylene were clearly detected by differential scanning calorimetry as thermal responses. These studies show that interface agents are preferably located in the amorphous phase of the system. A correlation between the crystalline content of the polymer component and the degree of grafting of the interface agent is also established. Further, a relationship between the thermal behaviour and the mechanical properties of the system seems to emerge.     

Modification of polypropylene with long-chain elastomers

Physicomechanical and rheological properties of isotactic polypropylene modified with a high-molecular-weight amorphous polymer, polyoctene, were studied. Modification of polypropylene with polyoctene allows the impact resilience and relative elongation to be increased relative to the initial polypropylene and the processing temperature to be decreased.     

载体γ-Al2O3和钐对非晶态NiB合金热稳定性的影响

用化学还原法制备了NiB、NiB/Al2O3和NiBSm/Al2O3三种催化剂，它们都呈非晶结构.用等离子耦合发射光谱仪(ICP)对催化剂组分进行了分析，采用差示扫描量热法（DSC）对三种催化剂进行了热稳定性分析.结果表明，载体的引入使非晶态NiB合金的体相组成中B的含量降低.将非晶态NiB合金负载到γ-Al2O3上,可以明显改善非晶态合金的热稳定性，少量Sm可以进一步提高晶化温度.晶化激活能数据亦表明了载体和Sm对非晶结构具有良好的稳定作用.载体和Sm可能通过不同的作用提高了非晶态合金的热稳定性.     

Characterization of Wallpaintings from the Caliphal Baths of Cordoba (Spain) by X-Ray Diffraction and Raman Microspectroscopy

Wallpainting fragments from the Caliphal Baths of Cordoba, Spain, were studied in this work for the first time. X-ray diffraction (XRD) and Raman microspectroscopy allowed the chemical nature of the pigments used by the Arabic artists of the time to be identified. All pigments were applied over a gypsum priming layer. The white, red, and yellow colors used were obtained from gypsum, hematite, and goethite, respectively. Some pigments were prepared by mixing these materials. The analytical techniques used also allowed the mortar material to be identified. The results of this study may be useful to develop effective conservation strategies for archaeological remains.     

IR spectroscopic study of the structure of isotactic polypropylene deformed by the crazing mechanism

The deformation of isotropic isotactic polypropylene with a spherulitic initial structure has been studied. Fourier transform IR spectra of polypropylene deformed to various stretch ratios in air and in a physically active medium have been recorded. From the spectroscopy data, the dichroic ratios and orientation functions have been calculated for the amorphous and crystalline polypropylene phases. It turned out that the orientations of macromolecules in the amorphous and crystalline polypropylene phases change identically while stretching in a physically active (water–ethanol) medium. However, the deformation in air leads to a more pronounced orientation of macromolecules in the crystalline phase as compared with the orientation in the amorphous phase. The maximum values of the orientation function in the deformation in air coincide with the stretch ratio at the yield point. This is how a physically active medium acts in crazing in comparison with shear deformation in air.     

Photodegradation of Heterophasic Ethylene-Propylene Copolymers in the Solid State

The photodegradations of various heterophasic ethylene-propylene (E-P) copolymer films were studied at 30 and 55°C in air for varying time intervals. The photochemical behavior of E-P copolymers is quite different from amorphous polypropylene and polyethylene homopolymers but resembles that of isotactic polypropylene. The nonvolatile products in photooxidized copolymer films have been quantitatively identified by infrared analysis. The kinetics and general oxidation mechanism scheme for E-P copolymer are presented. The identification of γ-lactone is an indication of the importance of an intramolecular back-biting process. The overall functional group distribution is found to differ from that in polyethylene and E-P copolymers.     

Oxygen uptake by isotactic polypropylene of different morphological structure

Oxygen uptake by isotactic polypropylene was studied at temperatures below melting point, on samples of various degrees of crystallinity and spherulite size. Diffusion coefficients and activation energy of diffusion were calculated. It is suggested that the dependence of the rate of oxygen uptake on the morphological structure of polymer samples can result from different values of the interspherulitic amorphous phase fraction, which is more easily accessible to oxygen than the interlamellar fraction.     

Thermal reactions of solid-state amorphized borates and borate glasses

The properties and course of phase transition of amorphous borates obtained by solid-state thermal and mechanical treatment of hydrated borates and melt quenched glasses with the compositions of these borates were studied. Processes of structural relaxation and crystallization were considered.It was found that different methods of preparation of amorphous borates and the differences in their structural ordering resulting from these methods affect the rate and the mechanism of transformations occurring during their heating.Support for this work was provided by the Polish Committee of Scientific Research (KBN) — grant No. 3 P407 034 06.     

Acid/Base Properties and Adsorption of an Azo Dye on Coating Pigments

Adsorption of an anionic disazo dye, Food Black 2 on coating pigments from polar solvents was studied. Pigments (kaolin, precipitated CaCO₃, amorphous SiO₂, TiO₂, Al₂O₃, and talc) were chosen to be representative of those used in paper for ink‐jet printing. The predominating driving force for the adsorption was electrostatic interactions for all the pigments except talc, for which hydrophobic interactions were dominant. Lewis acid‐base properties of the pigments were studied by measuring adsorption of Lewis acid‐probe molecules from both polar and nonpolar media. The pigments studied were found to be amphoteric, containing both acidic and basic surface groups. However, in the presence of polar solvents, the adsorption of acid‐base probe molecules was greatly reduced, which indicates that Lewis acid‐base interactions have only a small influence on the adsorption of azo dyes from polar media such as water.     

Optimization of the elimination of lipids from the microalgaChlorella vulgaris

Summary Using the microalgaChlorella vulgaris as an example, the possibility has been shown of eliminating the lipids and pigments by oxidizing it with hydrogen peroxide without changing the compositions of the protein-carbohydrate complex. The influence of the conditions of performing the oxidation of theChlorella biomass have been studied and it has been described mathematically. The optimum conditions for eliminating the lipids and pigments have been found and the general chemical properties of the protein product isolated have been determined.N. D. Barabash took part in the work.Siberian Technological Institute, Krasnoyarsk. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 426–430, July–August, 1976.     

Enhanced Anticorrosion Properties of Epoxy Coatings from Al and Zn Based Pigments

Anticorrosion epoxy coatings from Al and Zn based pigments were synthesized by adjusting their volume ratios, aiming at their increasing anticorrosion performances. The anticorrosion properties were examined via electrochemical impedance spectroscopy, Tafel polarization curve analysis and salt spray test. The coating morphologies before and after the salt spray tests were studied via scanning electron microscopy(SEM). The elemental and chemical compositions of the corroded surfaces of the coatings were analyzed by means of X-ray photoelectron spectroscopy(XPS). The results indicate that the coating composed of Al/Zn at 10:1(volume ratio) displays the maximum anticorrosion performances, which are superior to those of pristine Al or Zn based pigment.     

Thermochemical characterization of chicken litter and peat as a source for energy recovery

The shortage of raw materials and the environmental problems due to pollution require development of new green technologies utilizing some wastes and transforming them to secondary raw materials. The aim of this work is to study the properties of poultry waste to propose possibilities to minimizing the released emissions and avoiding the risk for human health and the environment. At the same time, two types of low grade peats with different origin are studied as components for the production of soil conditioners. During the studies, we applied the inductively coupled plasma (ICP) and chemical analysis, powder X-ray diffraction, thermal analysis, IR spectroscopy, and scanning electron microscopy for determining the composition, crystal phase, the shape and size of particles, and thermal stability of the investigated samples. The chemical and the phase compositions of the studied samples confirmed that the content of nutrient compounds and of the carbon substances is suitable as an effective secondary raw material for soil conditioners. It is found that the poultry wastes and peat samples have a similar phase and chemical composition and contain an organic mass in the form of carbon components with amorphous, fibrous, and skeleton-like structure, suitable to be combined with other nutrient-containing compounds. During the thermal treatment, the carbon compounds are oxidized releasing heat. Based on that the materials under study are considered as environmentally friendly fuels, releasing relatively low emissions.     

Modelization of photocatalyzed oxidation of polyolefins. II. ZnO and TiO2 photocatalyzed decomposition of tert-butyl hydroperoxide and atactic polypropylene hydroperoxides

Direct evidence of the TiO₂ and ZnO photocatalytic decomposition of tert-butyl hydroperoxide and atactic polypropylene hydroperoxides in solution is reported. Molecular and macromolecular hydroperoxides behaved similarly. Untreated TiO₂ in the rutile form was a far more efficient photocatalyst than ZnO in solution; the photoactivities of both pigments were limited on preferential absorption sites. In the solid state no preferential reaction sites were observed. When added to preoxidized atactic polypropylene both pigments were photocatalysts of the formation of macromolecular hydroperoxides and of their decomposition. The photoreactivities of untreated TiO₂ and ZnO varied less than in solution.     

Separation of pyranoanthocyanins from red wine by column chromatography

With the aim of monitoring the formation of anthocyanin-derived pigments and contributing to the study of their chromatic properties, stability and relative contribution to the colour of red wines, a method for fractionation of the colouring material was set up. The method was based on the distinct reactivity of the different pigment families towards bisulfite (hydrogen sulfite). The wine, acidified and bleached with NaHSO₃, was placed in a Toyopearl^® HW-40(s) gel column and submitted to elution with ethanol. Two fractions with different pigment compositions were collected and analysed by liquid chromatographay diode array detection-mass spectrometry. Compounds present in each fraction were identified according to their UV-visible and MSⁿ mass spectra, showing that the first one was mostly constituted of pyranoanthocyanins, whereas the second basically contained anthocyanins and anthocyanin-flavanol condensation products. A large variety of new pigments were detected, some of which had not been previously reported in red wines, as far as we know. Characteristic MS² and MS³ fragmentation patterns were observed within each family of compounds, which could be further applied for characterisation of unknown pigments in other wines.     

The Effect of Compatibilizer on the Properties of Impact Poly(propylene)-Wood Composites

The effect of two compatibilizers, polypropylene graft maleic anhydride (PPgMA) and ethylene vinyl alcohol (EvOH), on the physical properties of wood polymer composites were studied. The composites were prepared with pine wood and two different impact polypropylene polymers, where the polymers varied according to ethylene content. These compatibilizers, when used together and pre-reacted to create a joint compatiblizer of PPgMA and EvOH, significantly improved control over the repeatability of the physical properties tested, compared to when the compatibilizers were used individually. The impact values were slightly reduced, however the standard deviation of these values showed that the variation in the impact properties were significantly minimized when EvOH was also introduced. It appears that the joint compatiblizer provides better control over the hardness to impact balance of these composite materials and some of these physical properties were improved depending on the ratio between PPgMA and EvOH used, in the joint compatibilizer. Due to the difference in chemistry between PPgMA and EvOH, we expected PPgMA to interact more with the crystalline polypropylene matrix of the impact polymer and the EvOH with the amorphous, rubbery part and yield interesting results.