Morphology and properties of ternary polyamide 6/polyamide 66/elastomer blends

The aim of the work presented is to evaluate the mechanisms and phase interactions in ternary blends based on different polyamides and functionalised elastomers, and to establish a correlation between the morphology controlled by the specific binary interactions, and physical and technological properties, respectively. The properties of the ternary system polyamide 6/polyamide 66/ elastomer depend on the specific blend morphology which is determined mainly by the differences of the surface tension of the components. A phase‐in‐phase structure was observed by microscopic study (AFM) in the ternary polyamide 6/polyamide 66/elastomer blends with maleic anhydride grafted ethene‐octene copolymer, and a “quasi” phase‐in‐phase structure in blends with maleic anhydride grafted ethene‐propene‐diene copolymer as the elastomer phase. An incorporation of polyamide inside of the elastomer particles was observed in the first case due to the difunctionality of polyamide 66. This type of morphology causes an increased elongation at break and toughness of these blends. In comparison to the binary polyamide based blends the ternary blends show an increased elastic modulus, elongation at break and yield stress as well as a high impact strength at low temperatures up to ?20 °C. Copyright © 2003 John Wiley & Sons, Ltd.     

Kristallstrukturen und spektroskopische Untersuchungen ternärer CuII-Komplexe mit bicyclischen Dicarbonsäuren und N,N-Donor-Liganden

Crystal Structures and Spectroscopic Investigations of Ternary Cu^II-Complexes with Bicyclic Dicarboxylic Acids and N,N-Donor Ligands The synthesis of coordination compounds [CuLdam] · 3H₂O (H₂L = 7-oxa-bicyclo[2.2.1]heptane-2-exo,3-cis-dicarboxylic acid ( 1 ) and its 1-methyl-derivative ( 2 ); dam = ethylendiamine, 1,2- and 1,3-propylendiamine, 2,2′-dipyridyl, 1,10-phenanthroline) has been described. Results of visible and IR spectroscopy and magnetic data are given. In the result of X-ray analyses of [CuL¹dipy] · 3H₂O ( 1 d ) and [CuL²en] · 3H₂O ( 2 a ) the dicarboxylate anions of 1 and 2 proved to be tridentate chelating ligands. In 1 d the Cu atom has an approximately square-pyramidal coordination with the bridging O atom in the apical position. In 2 a , however, the coordination number is extended to six by an O atom of a second [CuL²en] unit resulting in a centrosymmetric complex dimer with octahedrally coordinated Cu atoms. The water molecules do not participate in the coordination of the Cu atoms and form a complicated system of hydrogen bonds in the crystal.     

Transmission analysis in ultrafiltration of ternary protein mixture through a hydrophilic membrane

One of the main reasons for the underutilization of ultrafiltration has been the lack of experimental data on transmission of proteins for complex systems and its corresponding theoretical analysis. Of course, the presence of fouling coupled with concentration polarization have had their share in making ultrafiltration operation a difficult one to understand. In the present study, the systematic ultrafiltration of 3-protein mixture, namely lysozyme, myoglobin and ovalbumin, has been carried out using a hydrophilic 30,000 molecular weight cut off membrane. The experimental data of individual protein transmission in ternary mixture showed a very low transmission (as low as 3% for ovalbumin) to a very high transmission (as high as 90% for lysozyme) of proteins for different operating conditions. This behaviour of each protein in the mixture was analyzed using combined concentration polarization and irreversible thermodynamics model. The parameters of the modeled values gave a very good fit with experimental data and the resulting analysis indicated some interesting findings, which are discussed in this paper. The comparison of parameters obtained for single protein solution and the ternary protein solution showed some unusual results that point to the presence of the protein–protein and protein–membrane interactions.     

Studies on the kinetics of synthesis of TiC by calciothermic reduction of TiO<Subscript>2</Subscript> in presence of carbon

Reaction kinetics of the formation of TiC by calciothermic reduction of TiO₂ in presence of carbon have been investigated using thermal analysis (TG-DTA) of a powder mixture of TiO₂, Ca, and C in argon atmosphere at different heating rates. Both the reaction initiation and the peak temperatures are found to increase with heating rates. The appearance of exothermic peaks in the DTA plots after Ca melting indicates the reduction of TiO₂ by liquid calcium and formation of TiC by in-situ reaction of Ti with C. The apparent activation energy of the process has been found to be 170.8±0.5 kJ mol^–1.     

Role of alcohol in microemulsions as determined from volume and heat capacity data for the water-sodium dodecylsulfate -n-butanol system at 25°C

Densities and heat capacities of the ternary system water-sodium dodecylsulfate — n-butanol were measured at 25°C over the complete alcohol mole-fraction or solubility range. Apparent and partial molar volumes and heat capacities of n-butanol were derived and have been analyzed as a function of the concentration of both the surfactant and the alcohol. Characteristic changes suggest that, at low concentrations, n-butanol is partially solubilized in mixed micelles but, in concentrated alcohol solutions, n-butanol largely exists in the form of microaggregates stabilized by the surfactant. Results would also suggest that at low concentrations of n-butanol another transition zone occurs in the micellar structure around 0.2–0.3 mol-kg^–1 in sodium dodecylsulfate.     

Ringed spherulites in ternary polymer blends of poly(<Emphasis Type="Italic">ε</Emphasis>-caprolactone), poly(styrene-<Emphasis Type="Italic">co</Emphasis>-acrylonitrile), and polymethacrylate

The relationship between ringed spherulite morphology, crystallization regimes/kinetics, and molecular interactions in miscible ternary blends of poly(-caprolactone) (PCL), poly(benzyl methacrylate) (PBzMA), and poly(styrene-co-acrylonitrile) (SAN) was investigated by using differential scanning calorimetry (DSC), polarized optical microscopy (POM), and wide-angle X-ray diffraction (WAXD). The interactions resulted in the deviation of both experimental and calculated T_gs and formation of the specific morphology of the spherulitic structure. Ring-banded spherulites were observed in the PCL/PBzMA/SAN ternary blends. The width of ring bands changed with the blend ratio and the crystallization temperature. Additionally, both composition and wt% of AN in the SAN copolymer had an apparent effect on the morphology of PCL spherulites. Both the crystallization structure of lamellae and molecular interactions greatly influenced the ring bands of PCL spherulites. Furthermore, by using the Flory–Huggins approximation, the depression of the melting point showed that interactions in the PCL/PBzMA/SAN-17 blend were greater than in the PCL/PBzMA/SAN-25 blend. In the ternary blends, the great molecular interactions between amorphous and crystalline polymer resulted in better homogeneity and a larger band period of the extinction rings in the PCL spherulites.     

The study of esterifying reaction between epoxy resins and carboxyl acrylic polymers in the presence of tertiary amine

In this article, the fixed gel/nongel point and critical gel point experiments are designed for formulating the regulation of esterification reaction between epoxy resin and carboxyl acrylic polymer in the presence of tertiary amine in organic solvent. Ternary diagrams are employed to illustrate experimental results. It is disclosed that some factors, such as mole ratio of the ternary reactants, molecular weight of epoxy resin, even the hydrophilic solvent content of system, play important roles in the gelling effect of esterification reaction. In order to explain these experimental results, a suggested reaction process is put forward and, subsequently, a critical gel equation is derived from Carothers gelation theory. The equation provides an explicit connection between the critical gel composition and the relevant parameters of the reaction system such as average carboxyl functionality of acrylic resin, average molecular weight of epoxy resin, the base intensity of tertiary amine, and the solid content of system. The regressive critical gel curve based on the equation is well consistent with the experiment data. It expresses that the suggested reaction process is reasonable. Finally, based on the critical gel equation, the important factors that influence the esterification result are discussed qualitatively. All the achievements are beneficial to understanding the reaction process and avoiding useless gelation in preparing the water-reducible compositions.     

Solid State Reactions in the Al‐Si‐C System

The study is aimed to prevent the formation of the aluminium carbide compound Al₄C₃ that negatively affects Al‐Si‐C based materials. The reaction products of elementary aluminium, silicon and graphite as well as aluminium with either β‐SiC or α‐SiC without and with graphite at temperatures 1200°‐2500 °C under different atmospheres and reaction times were characterized using powder X‐ray diffraction and scanning electron microscopy (SEM) with an energy dispersive X‐ray (EDX) analysis. The results of the powder diffraction study show that under the conditions (1450 °C; 8 h; vacuum) the formation of Al₄C₃ could be prevented. The reaction products at those conditions consist of the ternary compound Al₄SiC₄ besides SiC and residual carbon. The ternary aluminium silicon carbide Al₄SiC₄ crystallizes in a hexagonal crystal system with unit cell dimensions a = 327.64(4) pm, b = 2171.2(6) pm and space group P6₃mc (no. 186). The crystal structure of Al₄SiC₄ is isostructural with Al₅C₃N and consists of layers of Al₄C₃ and SiC.     

CeCl3-CdCl2-H2O和CeCl3-CdCl2-HCl-H2O的相平衡

测定了三元系CeCl₃-CdCl₂-H₂O (25 ℃)和四元系CeCl₃-CdCl₂-HCl(～8.4％)-H₂O(25 ℃) 的相平衡溶度数据,绘制了相应的溶度图.该三元系是由5个固相区CdCl₂&;#8226;2.5H₂O(原始盐)、CdCl₂&;#8226;H₂O(原始盐)、6CdCl₂&;#8226;CeCl₃&;#8226;14H₂O、4CdCl₂&;#8226;CeCl₃&;#8226;12H₂O、CeCl₃&;#8226;7H₂O(原始盐)组成的复杂体系.该四元系是由5个固相区CdCl₂&;#8226;H₂O(原始盐)、9CdCl₂&;#8226;CeCl₃&;#8226;19H₂O、6CdCl₂&;#8226;CeCl₃&;#8226;14H₂O、4CdCl₂&;#8226;CeCl₃&;#8226;12H₂O、CeCl₃&;#8226;7H₂O(原始盐)组成的复杂体系.其中6CdCl₂&;#8226;CeCl₃&;#8226;14H₂O在该三元系是介稳化合物.9CdCl₂&;#8226;CeCl₃&;#8226;19H₂O 、6CdCl₂&;#8226;CeCl₃&;#8226;14H₂O和4CdCl₂&;#8226;CeCl₃&;#8226;12H₂O用X射线粉末衍射及TG-DTG和DSC等方法进行了研究,并对X射线粉末衍射进行了指标化.