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1.
Ha Neul Kim Chang Kyu Park Ick Soo Kim Seong Hun Kim 《Polymer Engineering and Science》2020,60(6):1365-1376
In the present study, compatibilization of immiscible blends of polymers was investigated based on the Pickering emulsion concept with various mixing procedures. Silica nanoparticles were incorporated into poly (1,4-cyclohexanedimethylene isosorbide terephthalate) (PEICT)/isotactic polypropylene (iPP) blends. Localization of nanoparticles was effectively modified by varying mixing procedures. Relocation of hydrophilic silica occurred in a secondary mixing procedure with the PEICT, which has relatively high affinity when primarily mixed with iPP. The final location of the silica nanoparticles was confirmed by SEM images. SEM and an optical microscope were used to follow morphological change. By simply changing the mixing procedure, the hydrophilic silica nanoparticles were able to perform the role of a morphology modifier successfully without modifying the surface characteristics. The mechanical properties and crystallization behavior were also compared depending on the surface characteristics of the silica nanoparticles and their final localization. 相似文献
2.
Morteza Ganjaee Sari Siamak Moradian Saeed Bastani Norbert Stribeck 《应用聚合物科学杂志》2012,124(3):2449-2462
Fiber‐graded poly(propylene) was modified by polyester‐amide‐based dendritic nanostructures with the aim of improving its dyeability. Two different dendritic polymers were used and the dendritic nanostructures were formed in situ via reactive blending with maleic anhydride‐modified poly(propylene). Samples were chosen exploiting a 4‐component mixture design. Thermal, morphological, and rheological characterizations showed domains with different size and distribution were formed and primary properties of the dendritics determined the characteristics of the resulted domains. Morphological parameters were quantified by digital analysis of scanning electron microscope images. Thermal and rheological behavior also demonstrated good agreements with the inferred morphology of the formed dendritic domains. The modified samples were then dyed with dispersed dyestuffs. A variety of substantivities were obtained, and some of the modified samples showed a significant enhancement in dyeing properties. A predictive model was developed for K/S ratio, where K and S are absorption and scattering coefficients of the Kubelka‐Munk one constant theory, respectively. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
3.
In this study, we prepared and characterized membranes containing polypropylene, poly(ethylene‐co‐vinyl acetate) (EVA), and poly(vinyl alcohol) (PVA). The production process involved blend extrusion and calendering followed by solvent extraction by toluene and water of the EVA and PVA phases. Morphology studies involving scanning electron microscopy determined the pore size distribution at the surface and in the internal regions of the membrane. The resulting membrane properties were related to the processing variables (extension rate, process temperature, and solvent extraction methods) and blend composition. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3275–3286, 2004 相似文献
4.
Fine polypropylene fiber has many excellent properties, but it is difficult to dye because of the absence of dye sites in the molecular chain and high crystallinity. Fine polypropylene/hybrid polystyrene (yttria) fiber melt‐spun from blends of polypropylene and a small amount of nanohybrid polystyrene with modified yttria incorporated was prepared to improve the dyeing properties. The dyeability, orientation, degree of crystallinity, phase morphology, and mechanical properties of pure polypropylene and the blend fibers were investigated. It was found that the crystallinity and morphology of these phases in the blend systems were different. With the existence of nanohybrid polystyrene, the fine modified polypropylene filaments had practical mechanical properties, the amorphous region of the polypropylene/hybrid polystyrene (yttria) fiber increased, and the modified polypropylene fiber dyed easily and had good fastness to soaping because of the complexation of the disperse dye and yttrium in the blend system. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
5.
Ya Liu Bowen Cheng Na Wang Weimin Kang Weili Zhang Keqi Xing Wenjuan Yang 《应用聚合物科学杂志》2012,124(1):296-301
In this study, a new type of polypropylene (PP)/polyester (PET) bicomponent melt‐blown (bi‐MB) for filtration was developed through the melt‐blowing process with raw materials of melt‐blown (MB)‐grade PP and PET chips. The structure, porosity, and filtration performance of the bi‐MBs were tested through relevant instruments. The results show that the average fiber diameter in the bi‐MBs was 2–3.5 μm, the average pore size was 12.3–15.6 μm, and the porosity was 90–94%. The results also show that the filtration efficiency of the bi‐MBs was much higher than that of monocomponent PP MBs. It reached the highest value of 97.34% when the PP/PET ratio was 50/50 and could be used as high‐performance filter media. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
6.
A two-step process has been invented to prepare sulfonated polypropylene from chlorinated polypropylene via thiolation and successive oxidation to enhance the dyeability of polypropylene. With a short thiolation reaction time of 3 h in an N-methyl-2-pyrrolidone solution, 1.7–20.5% sulfur can be incorporated into a polypropylene bulk effectively. Chlorine–thiol substitution and hydrosulfide conversion have been examined with elemental analysis, and their behaviors as a function of the SH/Cl ratio can be explained with an equilibrium model of hydrosulfide and accessible chlorine in a given timescale. Oxidation of thiol has been performed successfully with hydrogen peroxide. The evolution of oxidation intermediates such as sulfoxide, sulfone, sulfinic acid, and sulfonic acid can be identified by Raman and Fourier transform infrared analyses. Sulfonated polypropylene can be stained by a basic dye very effectively, and its dye uptake reaches 190 mmol of dye/kg of polymer for 3.6 mmol of sulfur/g of polymer. This dye uptake is 20 times more effective than that of chlorinated polypropylene on a molar basis. Thus, it is clear that a modification can be performed effectively to enhance the dyeability of polypropylene. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
7.
Luis C. Mendes Fernanda C. Miranda Anderson F. Ferreira Fabiano M. Dias M. Elizabeth F. Garcia 《应用聚合物科学杂志》2003,88(9):2253-2260
The mechanical, thermal, and gas permeation properties of polypropylene (PP)/oligopinene systems in the form of compression thin films 10 μm thick, which were prepared by quenching (with liquid nitrogen) and slow‐cooling (15°C/min) techniques, were examined. The addition of oligopinene to PP changed the stress–strain curve of the polyolefin. Both for quenching and slow‐cooling films, with a higher oligomer content, no more yielding was observed, and the elongation at break abruptly decreased with greater than 10% oligomer. The elastic modulus and stress at break changed according to the thermal conditions of the film preparation. Thermal analysis revealed that the blend system had two glass‐transition temperatures for both types of films. The values of permeation to CO2 were independent of the film preparation and were practically unchangeable with the oligomer content in the blends, indicating that the overall decrease in the crystallinity was counterbalanced by the rigidity of the two amorphous phases. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2253–2260, 2003 相似文献
8.
Blends with different ratios of thermoplastic polyurethane/polypropylene (TPU/PP) were prepared by melt mixing using an internal Haake mixer. Properties of the blends were investigated using SEM micrographs of cryofractures and measurement of the mechanical strength, water absorption, cell culture, and platelet adhesion in vitro tests, which were compared with those of PVC blood bags. The effect of the addition of the ethylene–vinyl acetate (EVA) copolymer on the TPU/PP blend properties was investigated. The results indicated that a TPU/PP/EVA = 80/20/5 blend can be used as a new blood bag material. It was observed that the blend is homogeneous with higher mechanical strength than that of the commercial PVC blood bag. This blend also showed a compatible cell response in contact with L929 fibroblast cells and fewer tendencies to interaction with platelets compared to the PVC blood bag. Although the blends were immissible and no chemical reaction at the interface could be found, the blood compatibility of the blends were improved. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2496–2501, 2003 相似文献
9.
The effects of the glass‐bead content and size on the nonisothermal crystallization behavior of polypropylene (PP)/glass‐bead blends were studied with differential scanning calorimetry. The degree of crystallinity decreased with the addition of glass bead, and the crystallization temperature of the blends was marginally higher than that of pure PP at various cooling rates. Furthermore, the half‐time for crystallization decreased with an increase in the glass‐bead content or particle size, implying the nucleating role of the glass beads. The nonisothermal crystallization data were analyzed with the methods of Avrami, Ozawa, and Mo. The validity of various kinetic models for the nonisothermal crystallization process of PP/glass‐bead blends was examined. The approach developed by Mo successfully described the nonisothermal crystallization behavior of PP and PP/glass‐bead blends. Finally, the activation energy for the nonisothermal crystallization of pure PP and PP/glass‐bead blends based on the Kissinger method was evaluated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2026–2033, 2006 相似文献
10.
Ternary blends of polypropylene (PP), a polypropylene‐grafted acrylic acid copolymer (PP‐g‐AA), and an ethylene–acrylic acid copolymer (EAA) were prepared by melt blending. The surfaces of films with different contents of these three components were characterized with contact‐angle measurements. Scanning electron microscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis were used to characterize the microstructure, melting and crystalline behavior, and thermal stability of the blends. The contact angles of the PP/PP‐g‐AA blends decreased monotonically with increasing PP‐g‐AA content. With the incorporation of EAA, the contact angles of the PP/PP‐g‐AA/EAA ternary blends decreased with increasing EAA content. When the concentration of EAA was higher than 15 wt %, the contact angles of the ternary blends began to increase. Scanning electron microscopy observations confirmed that PP‐g‐AA acted as a compatibilizer and improved the compatibility between PP and EAA in the ternary blends. Differential scanning calorimetry analysis suggested that acrylic acid moieties could act as nucleating agents for PP in the polymer blends. Thermogravimetric analysis and differential thermogravimetry confirmed the optimal blend ratio for the PP/PP‐g‐AA/EAA ternary blends was 70/15/15. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 436–442, 2006 相似文献
11.
Akiyoshi Takeno Minoru Miwa Teruyuki Yokoi Keishi Naito Ali Akbar Merati 《应用聚合物科学杂志》2013,128(6):3564-3569
The aim of this study was to investigate crazing that generates regular crazes in polymeric fibers. For carrying out this study, we designed and fabricated an experimental apparatus for generating crazes on polypropylene (PP) filaments. By an optical micrograph and a laser scanning micrograph of the surface and cross‐section of the filaments, it was confirmed that the crazes were generated on the surface of the filaments. Optical microscopes and measurements of the craze morphology on the filaments showed that approximately 30–50% of the contact area was crazed. As the crazing tension increased, the interval between the crazes increased, but the width of the crazes did not change significantly. Moreover, it was confirmed that the filaments had a homogenous crazed structure and pores were formed in their structure. The crazing process did not affect the strength of the crazed filaments significantly; the crazing process decreased the light transmittance of the filaments. The acid dyeing was adsorbed onto crazed region of PP filaments. These crazes in the filaments have the potential to lead to new methods for dyeing PP fibers. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
12.
The compatibilizing effect of the triblock copolymer poly(styrene‐b‐ethylene‐co‐butylene‐b‐styrene) (SEBS) on the morphological and mechanical properties of virgin and recycled polypropylene (PP)/high‐impact polystyrene (HIPS) blends was studied, with the properties optimized for rigid composite films. The components of the blend were obtained from municipal plastic waste, PP being acquired from mineral water bottles (PPb) and HIPS from disposable cups. These materials were preground, washed only with water, dried with hot air, and ground again (PPb) or agglutinated (HIPS). Blends with three different weight ratios of PPb and HIPS (6:1, 6:2, and 6:3) were prepared, and three different concentrations of SEBS (5, 6, and 7 wt %) were used for investigations of its compatibilizing effect. Scanning electron microscopy showed that SEBS reduced the diameter of dispersed HIPS particles in the globular and fibril shapes and improved the adhesion between the disperse phase and the matrix. However, SEBS interactions with PPb and HIPS influenced the mechanical properties of the compatibilized PPb/HIPS/SEBS blends. An adequate composition of PP/HIPS, for both virgin and recycled blends, for applications in composite films with characteristics similar to those of synthetic paper was obtained with a minimal amount of SEBS and a maximal HIPS/PP ratio in the range of concentrations studied. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2861–2867, 2003 相似文献
13.
Polypropylene (PP) and acrylonitrile–butadiene–styrene blends of different composition were prepared using a single‐screw extruder. The binary blend of PP/ABS was observed to be incompatible and shows poor mechanical properties. PP‐g‐2‐hydroxyethyl methacrylate (2‐HEMA) was used as a compatibilizer for the PP/ABS blends. The ternary compatibilized blends of PP/ABS/PP‐g‐2‐HEMA showed improvement in the mechanical properties. Electron micrographs of these blends showed a homogeneous and finer distribution of the dispersed phase. The mechanical performance increased particularly in the PP‐rich blend. The 2.5‐phr (part per hundred of resin) compatibilizer was observed to bring improvement to the properties. The suitability of various existing theoretical models for the predication of the tensile moduli of these blends was examined. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 72–78, 2003 相似文献
14.
Dynamic shear in the axial direction of a rotor was vertically superposed on the melt flow direction, and its effects on the shear rate and melt strength were investigated theoretically. Polypropylene/high‐density polyethylene blends were microcellularly foamed with different vibration parameters. The experimental results were compared with those of a theoretical analysis, and the effects of dynamic shear on the foamability and ultimate cell structure were analyzed in detail. The theoretical results showed that the shear rate and melt strength increased with an increase in the vibration amplitude and frequency. The enhanced melt strength could effectively restrict cell growth, prevent cell rupture, and improve foamability. The experimental results showed that the cell orientation decreased and the cell structure was improved when axial dynamic shear induced by rotor vibrations was superposed on the melt flow direction. Furthermore, the cell diameter decreased and the cell density increased with increases in the vibration amplitude and frequency. The experimental results were very consistent with the theoretical analysis. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
15.
Stearyl alcohol ethoxylated additives were melt‐blended in polypropylene (PP) films, and the characteristics of the modified films were investigated. The melt blending of stearyl alcohol ethoxylates improved the hydrophilicity of the PP films through additive surface segregation. Surface specific techniques, such as X‐ray photoelectron spectroscopy and time‐of‐flight secondary‐ion mass spectrometry, were used to study the surface compositions of the samples modified with ethoxylated additives. This revealed that the surface concentrations of the additives were significantly higher than the bulk concentrations in all samples. In addition, the surface compositions of the additive‐modified samples continuously changed, even after the films were fully solidified. We also found that the resulting surface characteristics were very dynamic, so the melt‐additive‐containing polymer surfaces responded to water exposure, and their surface properties and morphologies were altered as a result. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
16.
The compatibilization of polypropylene (PP)/nylon 6 (PA6) blends with a new PP solid‐phase graft copolymer (gPP) was systematically studied. gPP improved the compatibility of PP/PA6 blends efficiently. Because of the reaction between the reactive groups of gPP and the NH2 end groups of PA6, a PP‐g‐PA6 copolymer was formed as a compatibilizer in the vicinity of the interfaces during the melting extrusion of gPP and PA6. The tensile strength and impact strength of the compatibilized PP/PA6 blends obviously increased in comparison with those of the PP/PA6 mechanical blends, and the amount of gPP and the content of the third monomer during the preparation of gPP affected the mechanical properties of the compatibilized blends. Scanning electron microscopy and transmission electron microscopy indicated that the particle sizes of the dispersed phases of the compatibilized PP/PA6 blends became smaller and that the interfaces became more indistinct in comparison with the mechanical blends. The microcrystal size of PA6 and the crystallinity of the two components of the PP/PA6 blends decreased after compatibilization with gPP. The compatibilized PP/PA6 blends possessed higher pseudoplasticity, melt viscosity, and flow activation energy. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 420–427, 2004 相似文献
17.
A maleic anhydride grafted thermoplastic elastomer (TPEg) was prepared. The effect of the TPEg on the morphology and performance of polypropylene (PP)/polyamide 6 (PA‐6) blends was studied. The final properties of the blends were tuned through variations in the TPEg/PA‐6 ratios and TPEg and PA‐6 percentages in the blends. Scanning electron micrographs showed that the TPEg greatly improved the homogeneity of the blends, and this led to better mechanical performance. The nonisothermal crystallization behaviors of PP and PA‐6 in the blends, revealed by differential scanning calorimetry, were different from those of pure PP and PA‐6. The crystallization temperature and rate of PP were promoted by the PA‐6 component because of its nucleating effect, whereas stepwise crystallization was detected for PA‐6 in the PP/PA‐6 blends when the TPEg was added. On the basis of these observations, a schematic model was proposed for these blends. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1806–1815, 2004 相似文献
18.
Potential and limits of dynamic mechanical analysis (DMA) as a tool for fracture resistance evaluation of isotactic polypropylenes and their polyolefin blends are presented. A minimum of information about the materials under investigation is a prerequisite to interpret the DMA traces in a right way. Although DMA is, in general, a powerful method to rank materials in term of toughness, care should be taken with (1) nucleated materials (where both intensity and strength of molecular relaxations need to be taken into account in material evaluation) and with (2) visbroken (i.e., peroxyde treated) grades. Except for these cases, the strengths of the principal or secondary molecular relaxation evaluated by DMA and the Charpy impact toughness correlate quantitatively when all the grades of a series exhibit unstable crack propagation. When changes in the macroscopic mode of fracture or in blend morphology occur, only qualitative correlations remain possible. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1854–1867, 2004 相似文献
19.
Humberto Lovisi Ana Lúcia N. Silva Luiz Claudio de Santa Maria Marisa C. G. Rocha Rosrio E. S. Bretas Marcelo Farah Fernanda M. B. Coutinho 《应用聚合物科学杂志》2003,89(6):1690-1695
The effect of addition of propylene copolymer, produced by metallocene catalysts, on the mechanical, rheological, and morphological properties of blends based on poly(propylene) (PP) and ethylene–1‐octene copolymer (EOC) was evaluated. It was observed that the addition of 2 wt % propylene–1‐octene copolymer (POC) improved the impact strength of the EOC/PP blends. The rheological analysis indicated that the addition of propylene copolymer produced materials with improved processability. Thermal and morphological analysis showed that the POC acts as a compatibilizer on the EOC/PP blends. © 2003 Wiley Periodicals, J Appl Polym Sci 89: 1690–1695, 2003 相似文献
20.
S. S. Ramkumar L. Shastri R. W. Tock D. C. Shelly M. L. Smith S. Padmanabhan 《应用聚合物科学杂志》2003,88(10):2450-2454
This article reports the results from a study conducted to characterize the frictional properties of friction spun yarns. The aim of the study was to obtain data on the surface mechanical properties of a variety of friction spun yarns. The study was essential as the surface mechanical properties influence the fabric formation, bonding strength, and high‐performance properties of yarns. The yarns used in the study were made from different fibers and were spun at different speeds. The capstan method was used to obtain the friction force values between the yarns and a glass cylindrical rod. The experiment was conducted at different tensions. The results indicate that the friction of friction spun yarns are influenced by different factors such as the type of fiber and tensions applied. The results obtained help to understand the surface mechanical properties of high‐performance yarns and their influence on the performance characteristics of friction spun yarns. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2450–2454, 2003 相似文献