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161.
Živković Dragana Živković ž. Šesták J. 《Journal of Thermal Analysis and Calorimetry》1998,52(2):393-401
The results of a comparative thermodynamic study of the Pb-Al binary system: activities, activity coefficients, partial and
integral molar quantities at 1000 K, obtained by experimental Oelsen calorimetry and thermodynamic predicting according to
Chou for systems with miscibility gap are presented in this paper. Also, infinite dilution constants and interaction parameters
at the mentioned temperature were determined by means of the Hajra method.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
162.
163.
稀溶液粘度法研究聚合物之间混溶性 总被引:6,自引:2,他引:6
介绍了几种粘度法判据,并对溶液中高分子-高分子,高分子-溶剂分子间的相互作用对混合物溶液粘度的影响进行了较为深入的讨论。 相似文献
164.
本文报道注射级酞侧基聚芳醚砜(PES-C)和聚芳醚酮(PEK-C)共混试样的玻璃化转变行为和部分力学性能的研究结果。并讨论共混工艺对相容性的影响。 PES-C和PEK-C树脂均由中国科学院长春应用化学研究所徐州工程塑料厂合成,在三氯甲烷中的比浓粘度ηsp/c(20℃)分别为0.45和0.47。将粉状树脂在GH-100Q高速搅拌器内按配方混合,并在烘箱内干燥后,用SHJ-30双螺杆挤出机在320~350℃(物料温度)挤出造粒。 相似文献
165.
Athena Kasselouri Anthony William Coleman Adam Baszkin 《Journal of colloid and interface science》1996,180(2):384
The miscibility of per-(6-amino-2,3-di-O-hexyl) β-CD hydrochloride salt abbreviated NH3-β-CD-OC6 with 1,2 dipalmitoyl, 3-sn-phosphatidyl choline (DPPC) and 1,2 dipalmitoyl, 3-sn-phosphatidic acid (DPPA) and of per-(6-dodecanoylamino-6-deoxy) β-CD abbreviated C11CONH-β-CD with DPPC has been assessed by surface pressure–area experiments under dynamic conditions. The determination of their mixing behavior has been approached by thermodynamic characterization derived from a comparison of the composition dependence of collapse pressure, for various contents of two components in monolayers, with that predicted from a model of ideal mixing. Component miscibility has additionally been addressed by the use of the Smaby–Brockman state equation for liquid-expanded monolayers which characterizes interaction between monolayer components using the water activity coefficient. While for both NH3-β-CD-OC6–DPPC and NH3-β-CD-OC6–DPPA systems the average surface areas followed the additivity rule, for the latter system surface pressures at collapse significantly deviated from ideality. The occurrence of an interaction at the level of oppositely charged polar groups of NH3-β-CD-OC6 and DPPA was also demonstrated by the nonideal composition dependence of the water activity coefficient (f1) characterizing the interfacial water. The mixing energies and interaction parameters at collapse pressures were calculated using the Joos approach. Positive values of these factors indicated that NH3-β-CD-OC6 and DPPA mixed films were thermodynamically less stable than the films in which ideal mixing of components occurred. The mixing of NH3-β-CD-OC6 with DPPC appeared to be almost ideal. In the case of the C11CONH-β-CD–DPPC system, analysis according to both the Joos and Goodrich approaches showed the occurrence of an important interaction which resulted in negative mixing energies characteristic of thermodynamically stable mixed films. 相似文献
166.
167.
Jin Ho Ryou Chang Sik Ha Won Jei Cho 《Journal of polymer science. Part A, Polymer chemistry》1993,31(2):325-333
Miscibility of blends consisting of poly(vinyl methyl ether) (PVME) and poly(styreneco-2-vinylnaphthalene) [P(S-co-2VN)] was investigated by means of Fourier transform infrared (FT-IR) spectroscopy and thermal analysis. Copolymers containing 21, 51, and 84 wt % of styrene were synthesized by radical polymerization. Based on optical clarity and glass transition temperatures, it was shown that the miscibility in P(S-co-2VN)/PVME blends is largely affected by compositions of the copolymers as well as concentrations of the blend. From the FT-IR results, the relative intensity at 1100 cm?1 peak of COCH3 band of PVME and the position of naphthyl ring of 2VN were sensitive to the miscibility of the blends. It was observed that blends of PVME with P(S-co-2VN) of 84 wt % styrene or P(S-co-2VN) of 51 wt % styrene are miscible over the entire concentration ranges of the blends. Blends of PVME with P(S-co-2VN) containing 21 wt % of styrene are immiscible below 65 wt % PVME. In the miscible P(S-co-2VN)/PVME blends, there was observed a large shift in the naphthyl frequency at a characteristic wavelength of 748 cm?1. © 1993 John Wiley & Sons, Inc. 相似文献
168.
H. W. Goh S. H. Goh G. Q. Xu 《Journal of polymer science. Part A, Polymer chemistry》2002,40(23):4316-4327
Miscible blends of poly(2‐hydroxyethyl methacrylate) (PHEMA) and poly(1‐vinylimidazole) (PVI) have been formed in methanol/water (3/2 v/v) solutions. The incorporation of 0.6 wt % C60 into PHEMA leads to hydrophobic interactions and enhanced hydrogen bonding in miscible blends of [60]fullerenated poly(2‐hydroxyethyl methacrylate) (FPHEMA) with PVI. The incorporation of 2.6 wt % C60 into PHEMA increases its tendency to form interpolymer complexes with PVI. Interpolymer complexes are formed when FPHEMA samples containing 0.6, 1.4, and 2.6 wt % C60 are blended with poly(4‐vinylpyridine). The yields of the complexes increase with increasing C60 content in FPHEMA. Calorimetry and Fourier transform infrared spectroscopy studies suggest the importance of hydrophobic interactions in C60‐containing blends and complexes. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 4316–4327, 2002 相似文献
169.
利用热分析研究了聚对苯二甲酸乙二醇酯(PET)与对苯二甲酸乙二醇酯(ET)-己内酯(CL)共聚物(TCL)共混体系的相容性,同时考察了体系中TCL组成分布不均一性及高温热处理对体系相容性的影响。 相似文献
170.
A dielectric relaxation study has been made over a frequency range of 106–10–3 Hz in the supercooled liquid state of the binary mixtures of 2-ethyl-1-hexanol (2EHOH) with a wide variety of common liquids. Differential scanning calorimetry measurements have also been made above 100 K. Our studies show compatibility of the methylcyclohexane with 2EHOH over the entire composition range. However, in the case of 1-bromobutane and acetone with 2EHOH, we have clearly seen two liquidlike phases separating out, which indicates incompatibility. In the case of 4-methyl-2-pentanol, the binary liquid shows no heterogeneity over most of the concentration range. In the case of methyl alcohol (MOH), the binary liquid shows some heterogeneity at a molecular level in the MOH-rich region. An attempt has been made to understand miscibility in terms of the preference for ring and chain formation among the alcohol molecules. 相似文献