bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation, characterization, and surface energetics of hydroxypropyl cellulose/polyethylenimine blends
Authors: Şengül Gamze , Demirci Serkan , Caykara Tuncer 
Published: July 2009

AbstractBlend films composed of hydroxypropyl cellulose (HPC) and polyethyleneimine (PEI) were prepared by solution casting method. The structure and mechanical properties of the blend films were analyzed by attenuated total reflectance Fourier transform infrared (ATR‐FTIR) spectroscopy and tensile strength tests. The ATR‐FTIR results indicated that there is a 5 cm−1 band shift to higher wave number due to the formation of hydrogen bonding between HPC and PEI components. The mechanical properties of the blends, such as breaking stress, elongation at break, and Young modulus were greatly affected with increase of PEI component. The contact angles of water, ethylene glycol, formamide, and diiodomethane drops were measured on the blend films. The contact‐angle results were evaluated in terms of surface free energy components using van Oss‐Good methodology. It was shown that the surface free energy components of HPC and its blends did not differ so much with the composition. However, the apolar Lifshitz‐van der Waals component ($\gamma^{\rm LW}_{S}$) values are higher than those of the Lewis acid–base interactions component ($\gamma^{\rm AB}_{S}$) values. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Electrospinning of poly(vinyl pyrrolidone): Effects of solvents on electrospinnability for the fabrication of poly(p‐phenylene vinylene) and TiO2 nanofibers
Authors: Chuangchote Surawut , Sagawa Takashi , Yoshikawa Susumu 
Published: July 2009

AbstractSeven different solvents (methanol, ethanol, 2‐propanol, 1,2‐dichloroethane, water, chloroform, and dichloromethane) were used to prepare electrospun poly(vinyl pyrrolidone) (PVP) fibers. The dielectric constant, viscosity, and surface tension of the solvents essentially affected the electrospinnability, morphological appearance, and size of the as‐spun fibers. Small and uniform as‐spun fibers could be fabricated from PVP solutions in solvents with a significantly high dielectric constant, low surface tension, and low viscosity. In three alcohol solutions (e.g., methanol, ethanol, and 2‐propanol), the diameters of as‐spun PVP fibers decreased with the dielectric constant, dipole moment, and density of the solvents increasing and with the viscosity of the solvents decreasing. Among these solvents, methanol was the best solvent, providing fibers with an optimal morphological appearance and a small fiber diameter. Mixing an unspinnable solvent with a solvent with a high dielectric constant, low surface tension, and low viscosity could increase the electrospinnability of the solution. The effects of solution properties and spinning conditions on the morphological appearance and diameter of electrospun PVP fibers were also carefully investigated. Under all investigated conditions for the electrospinning of a PVP solution in ethanol, the average diameters of the as‐spun fibers ranged from 200 nm to 1.5 μm. Well‐aligned PVP fibers were also produced with a rotating‐drum collector technique. Lastly, PVP was used in the fabrication of poly[2‐methoxy‐5‐(2′‐ethylhexyloxy)‐1,4‐phenylene‐vinylene] and TiO2 fibers by acting as a polymer carrier or guide. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Ultrasonic characterization of the crystallization behavior of poly(ethylene terephthalate)
Authors: Zhao Lijuan , Sun Zhigang , Tatibouët Jacques , Guo Shaoyun 
Published: July 2009

AbstractOn the basis of the previous observations that the ultrasonic signals are sensitive to the crystallization of polymers (Tatibouet and Piché, Polymer 1991, 32, 3147), we have expanded our efforts to study the detail relationship between the ultrasonic signals and crystallization process in this work. The nonisothermal and isothermal crystallization of virgin poly(ethylene terephthalate) (PET) and PET samples after degradation were studied by using a specially designed pressure‐volume‐temperature (PVT) device, with which an ultrasonic detector was combined. The results showed that the evolution of the ultrasonic signals not only can be used to probe the crystallization process but also can qualitatively characterize the crystallization rate, crystallinity, crystallite size, and amorphous. DSC measurement was used to verify such results. Ultrasonic signals could be as a complementary tool to polymer chain movement and well be applied to characterize the crystallization behavior. Furthermore, the ultrasonic measurement has the potential use to characterize crystallization of products in‐line during processing (i.e., injection molding, micromoulding). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Spectroscopic investigation of iron salts doped polyaniline
Authors: Vinodh Kumar Selvam , Mukherjee Samrat , Krishna Jakkan Bala Murli , Das Dipankar , Saha Abhijit 
Published: July 2009

AbstractIron salts have been doped into emeraldine base (EB) successfully using a chemical route. Both FeCl3 and FeSO4 were doped separately into EB in acetonitrile with metal ion and tetramer in the ratio of 4 : 1. The doped samples were characterized by UV‐vis absorption, Mössbauer and fourier transform infrared (FTIR) spectroscopy. UV‐vis spectra showed a suppression of the characteristic band of EB at 660 nm with an extended absorption towards the infrared regions for both the doped samples. FeSO4 showed electronic absorption behavior similar to the features of acid doped EB. Mössbauer spectroscopy confirmed the presence of single oxidation and high spin states of Fe(III) and Fe(II) in the respective doped polymers. No signature of Fe2+ was observed in the Fe3+ doped EB from the Mössbauer spectrum. FTIR spectroscopy showed a shift towards the lower wave number for the iron salts doped EB as compared to the pristine polymer. An increase in the intensity of the band at 1140 cm−1 is observed, which corresponds to the electronic like absorption confirming the doping of EB. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
In situ compatibilization between polystyrene‐grafted nano‐sized TiO2 and polypropylene with Friedel‐Crafts catalyst
Authors: Xu Lixin , Yang Mujie 
Published: July 2009

AbstractThe application of Friedel‐Crafts (FC) alkylation reaction to the in situ compatibilization between polystyrene‐grafted nano‐sized TiO2 (PS‐grafted TiO2) and polypropylene (PP) was assessed. The PS‐grafted TiO2 was first prepared via dispersion polymerization of styrene (St) using 3‐(trimethoxysilyl) propyl methacrylate treated nano‐sized TiO2 (MPS‐treated TiO2) as cores, and then dispersed within PP by melt blending with different contents of FC catalyst, AlCl3/St, to give PP/PS‐grafted TiO2 nanocomposites. The dispersion of PS‐grafted TiO2 in PP and interfacial adhesion of PP/PS‐grafted TiO2 nanocomposites were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM), respectively. The results indicated that the dispersion of PS‐grafted TiO2 in PP could be improved, with an enhancement of interfacial adhesion between TiO2 and PP, by introducing FC catalyst with adequate concentration, which led to a better thermal stability and resistance to ultraviolet (UV) aging of PP/PS‐grafted TiO2 nanocomposites. The effect of FC catalyst on the compatibilization between the PS‐grafted TiO2 and PP was discussed based on FC alkylation reaction mechanism. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and characterization of functionalized acrylic‐acrylamide‐based superabsorbent gels
Authors: Zhou Weili , Zhang Yuan , Jin Kemo , Qiu Xiaoyun , Ren Xueqin , Hu Shuwen , Zhang Fusuo 
Published: July 2009

AbstractWe have synthesized series of superabsorbent polymers (SAPs) by solution free radical polymerization of acrylic acid (AA), acrylamide (AM) with different functional monomers (FM). Three functional monomers including zwitterionic monomer [3‐(methacryloylamino) propyl] dimethyl (3‐sulfopropyl) ammonium (MPDSA), cationic monomer (3‐acrylamidopropyl) trimethylammonium chloride (APTAC) and anionic monomer 2‐acrylamidoglycolic acid monohydrate (AGAM) were selected to provide different charged groups on the superabsorbents. The effect of reaction parameters, such as degree of neutralization, content of initiator and crosslinker on the swelling capacity were assessed. The water absorbency of the superabsorbent were characterized in the distilled water, 0.9 wt % NaCl solution and the mixed solution containing 60 mg L−1 CaCl2 and 30 mg L−1 MgCl2, respectively. In addition, the swelling rate and water retention capacity in the soil were also investigated. Finally, the mechanism of different absorbency induced by the variety kinds of functional monomers was studied by XPS and FTIR, and tentative interpretation was presented as well. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Analysis and evaluation of the ionic interaction of the novel soft contact lenses using the zwitterionic polymer gel
Authors: Yamazaki Yoshiko , Matsunaga Toru , Ichinokawa Aya , Fujishiro Yoko , Saito Emi , Sato Takao 
Published: July 2009

AbstractIn the zwitterionic polymer gel which has cationic and anionic groups inside, it forms a complex to producing stability by adding thermal energy. We reported the behavior induced by the ionic interaction of them and the impact that a nonionic surfactant could exert on the complex formation. We had heating experiments of the zwitterionic polymer gel in PBS with a nonionic surfactant added. We analyzed DSC and measured the diameter, stress and flexure of heated the gel. As the result, it has been demonstrated that formation of strong ionic interactions inside the gel can be achieved by heating them in a solution containing the nonionic surfactant. It has been also demonstrated that the ratio of bound water is increased within the gel, promising an enhanced strength. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and characterization of polyurethane/Mg‐Al layered double hydroxide nanocomposites
Authors: Kotal M. , Kuila T. , Srivastava S. K. , Bhowmick A. K. 
Published: July 2009

AbstractLayered double hydroxide (LDH) is a new type of nanofiller, which improves the physicochemical properties of the polymer matrix. In this study, 1, 3, 5, and 8 wt % of dodecyl sulfate‐intercalated LDH (DS‐LDH) has been used as nanofiller to prepare a series of thermoplastic polyurethane (PU) nanocomposites by solution intercalation method. PU/DS‐LDH composites so formed have been characterized by X‐ray diffraction and transmission electron microscopy analysis which show that the DS‐LDH layers are exfoliated at lower filler (1 and 3 wt %) loading followed by intercalation at higher filler (8 wt %) loading. Mechanical properties of the nanocomposite with 3 wt % of DS‐LDH content shows 67% improvement in tensile strength compared to pristine PU, which has been correlated in terms of fracture behavior of the nanocomposites using scanning electron microscope analysis. Thermogravimetric analysis shows that the thermal stability of the nanocomposite with 3 wt % DS‐LDH content is ≈ 29°C higher than neat PU. Limiting oxygen index of the nanocomposites is also improved from 19 to 23% in neat PU and PU/8 wt% DS‐LDH nanocomposites, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
3D study on the effect of process parameters on the cooling of polymer by injection molding
Authors: Hassan Hamdy , Regnier Nicolas , Pujos Cyril , Defaye Guy 
Published: July 2009

AbstractPlastic injection molding (PIM) is well known as a manufacturing process to produce products with various shapes and complex geometry at low cost. Determining optimal settings of process parameters critically influence productivity, quality, and cost of production in the PIM industry. To study the effect of the process parameters on the cooling of the polymer during injection molding, a full three‐dimensional time‐dependent injection molding analysis was carried out. The studied configuration consists of a mold having cuboids‐shaped cavity with two different thicknesses and six cooling channels. A numerical model by finite volume was used for the solution of the physical model. A validation of the numerical model was presented. The effect of different process parameters (inlet coolant temperature, inlet coolant flow rate, injection temperature, and filling time) on the cooling process was considered. The results indicate that the filling time has a great effect on the solidification of the product during the filling stage. They also show that low coolant flow rate increases the heterogeneity of the temperature distribution through the product. The process parameter realizing minimum cooling time not necessary achieves optimum product quality and the complete filling of the cavity by the polymer material. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effects of glycerol and ethylene–acrylic acid on composition optimization of PVOH/starch‐blended biodegradable resin using response surface methodology
Authors: Li Yang‐Xiu , Peng Jinchyau , Lui Wai‐Bun , Lin Jenshinn 
Published: July 2009

AbstractResponse surface methodology was used to analyze the effect of glycerol (X1) and ethylene–acrylic acid (EAA) level (X2) on the objective (water solubility index (WSI), water absorption index (WAI), and tensile strength) attributes of a poly(vinyl alcohol) (PVOH)/starch‐blended plastic resin. A rotable central composite design was used to develop models for the objective responses. The experiments were run with different barrel temperatures, such as zone 1: 100°C, zone 2: 100°C, zone 3: 105°C, and zone 4: 105°C, respectively, with a feed rate of 20 g/min and screw speed of 25 rpm. Responses were most affected by changes in glycerol level (X1) and to a lesser extent by EAA level (X2). Individual contour plots of the different responses were overlaid, and regions meeting the optimum WSI of 6.10%, WAI of 5.57 g gel/g dry wt, and tensile strength of 62.14 MPa were identified at the glycerol level of 72.41 mL and the EAA level of 36.03 g, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Chitosan‐comb‐graft‐polyethylene glycol monomethacrylate—Synthesis, characterization, and evaluation as a biomaterial for hemodialysis applications
Authors: Radhakumary C. , Nair Prabha D. , Nair C. P. Reghunadhan , Mathew Suresh 
Published: July 2009

AbstractChitosan was reacted with “Polyethylene glycol monomethacrylate” (PEGm) using a redox initiation method. Different compositions were prepared by varying the relative amount of PEGm in the feed. A maximum of 88% yield with 320% grafting could be achieved. The graft copolymerization was confirmed by FTIR, thermal, and XRD studies. Higher graft % could be achieved as the monomer used is a macro monomer of PEG and the resultant graft is a comb‐like polymer. Grafting with PEGm did not affect the thermal stability of chitosan film significantly, however, it resulted in a marginal increase in the tensile strength of the films in the dry state. The products showed much improved swelling at pH 7.4 and pH 1.98 compared to the virgin chitosan. The preliminary biocompatibility evaluation showed that the materials are blood compatible and non‐cytotoxic. Though the permeability to low molecular weight solutes like creatinine and glucose was equal to or better than commercial cellulose membranes, the copolymer films expressed comparatively less permeability to these solutes initially, due to the crystalline domains of PEO grafts that impede the transport. On exposure in the medium, this effect is nullified culminating in better permeability. The crystallization of PEG grafts was very helpful in preventing the permeation of the high molecular weight solute albumin, the leakage of which above a certain limit is dangerous to the patient. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Optimized processing conditions for the preparation of dynamically vulcanized EPDM/PP thermoplastic elastomers containing PP resins of various melt indexes
Authors: Yeh Jen‐Taut , Lin Shui‐Chuan 
Published: July 2009

AbstractWe have investigated the mechanical and morphological properties of un‐vulcanized and dynamically vulcanized ethylene propylene diene terpolymer/polypropylene (EPDM/PP) thermoplastic elastomers prepared under various processing conditions and possessing various compositions. After melt‐blending EPDM and PP resins twice in a twin‐screw extruder, the values of tensile strength (σf) of the un‐vulcanized EPDM/PP samples were at most equal to that of the pure EPDM specimen, but were much lower than those of the pure PP specimens. The elongations at break (εf) of the un‐vulcanized EPDM/PP samples were, however, dramatically higher than those of their respective virgin PP resins, and they improved significantly upon increasing the shear viscosity (ηs) of the PP resins. The tensile properties of the dynamically vulcanized EPDM/PP samples were significantly better than those of the corresponding un‐vulcanized EPDM/PP specimens. Similar to the behavior of the un‐vulcanized EPDM/PP specimens, the tensile properties of the dynamically vulcanized EPDM/PP specimens were optimized when prepared at a screw rate of 115 rpm. Morphological analysis revealed that the un‐vulcanized and dynamically vulcanized EPDM/PP specimens both featured many EPDM domains finely dispersed in continuous PP matrices. Such domains were present on the surfaces of the dynamically vulcanized EPDM/PP specimens; the relative sizes of the vulcanized EPDM domains were minimized when the vulcanized EPDM/PP specimens were prepared at the optimal screw rate (115 rpm). In fact, under these conditions, the average sizes of the vulcanized EPDM domains decreased upon increasing the values of ηs of the PP resins used to prepare the vulcanized EPDM/PP specimens. To understand these interesting tensile and morphological properties of the un‐vulcanized and dynamically vulcanized EPDM/PP specimens, we measured the rheological properties of the base polymers and performed energy‐dispersive x‐ray (EDX) analyzes of the compositions of the un‐vulcanized and dynamically vulcanized EPDM/PP specimens. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Starch–acrylics graft copolymers and blends: Synthesis, characterization, and applications as matrix for drug delivery
Authors: Shaikh M. M. , Lonikar S. V. 
Published: July 2009

AbstractA series of acrylic monomers–starch graft copolymers were prepared by ceric ion initiation method by varying the amount of monomers. These graft copolymers were characterized by IR and 13C‐NMR spectroscopy. It was seen that as the concentration of monomer [acrylic acid (AA), methacrylic acid (MA), and methyl methacrylate (MMA)] increased the percent add‐on increased in all the graft copolymers, whereas grafting efficiency increased initially but showed a slight decrease with further increase in the monomer concentration (except for MMA). The release rate of paracetamol as a model drug from graft copolymers as well as their blends was studied at two different pH, 1.2 and 7.4, spectrophotometrically. The release of paracetamol in phosphate buffer solution at pH 1.2 was insignificant in the first 3 h for St‐g‐PAA‐ and St‐g‐PMA‐graft copolymers, which was attributed to the matrix compaction and stabilization through hydrogen bonding at lower pH. At pH 7.4, the release rate was seen to decrease with increase in add‐on. The tablet containing poly(methyl methacrylate) (PMMA) did not disintegrate at the end of 30–32 h, which may be attributed to the hydrophobic nature of PMMA. These results indicate that the graft copolymers may be useful to overcome the harsh environment of the stomach and can be used as excipients in colon‐targeting matrices. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation of poly(styrene‐co‐hexylacrylate)/cellulose whiskers nanocomposites via miniemulsion polymerization
Authors: Elmabrouk Aymen Ben , Wim Thielemans , Dufresne Alain , Boufi Sami 
Published: July 2009

AbstractA stable aqueous nanocomposite dispersion containing cellulose whiskers and a poly(styrene‐co‐hexylacrylate) matrix was prepared via miniemulsion polymerization. We were able to prepare a stable dispersion with a 20 wt % solid content and a cellulose whiskers content ranging from 1 up to 5 wt % based on polymer content. To avoid particle agglomeration leading to coagulum formation, the addition of a low amount of reactive silane, i.e., methacryloxypropyl triethoxysilane revealed to efficiently stabilize the dispersion. The nanocomposite dispersion was characterized using dynamic light scattering, transmission electron microscopy, and atomic force microscopy. Films obtained by casting followed by water evaporation and particle coalescence were analyzed by differential scanning calorimetry, dynamic mechanical analysis, and tensile testing. At 5 wt % whiskers loading, an enhancement by 500% of the storage modulus above the glass transition was determined. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation and analysis of a flexible curing agent for epoxy resin
Authors: Yang Y. , Chen Gong , Liew K. M. 
Published: July 2009

AbstractA kind of novel aromatic amine bis(4‐nonyl‐2,5‐diamine‐penoxyl)alkylate (RAn) as curing agents for epoxy resins were prepared through three steps of reactions using nonyl phenol and dibromoalkylate as materials. Dynamic mechanical analysis (DMA) indicated that the secondary relaxation for the resins cured by RAn were generated by the nonyls in RAn molecules when temperature was below −50°C. Comparing with other reference resins, the enhancement for toughness of RAn cured‐resins were at least 15%, which were contributed by such secondary relaxation. Furthermore, stiffness of the networks and thermal properties of the resins were not influent by the flexible groups (nonyl) in RAn after curing, since the groups were located only in the branched chains of the networks. The mechanical and thermal properties of the new material have been significantly enhanced. The relevant method and procedure developed through this research have been granted Chinese patent recently (Yang and Gong, Chin. Pat. CN1978483A, 2007). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
A suspension of spheres in a dilute polymer solution
Authors: Grisafi S. 
Published: July 2009

AbstractThe Hookean dumbbell model of a macromolecule predicts non‐uniform density and pressure fields surrounding a sphere buoyant in a dilute polymer solution when the size of the sphere is of the same order of magnitude as the size of the macromolecules. Using this prediction, the root mean square separation distance of a suspension of spheres buoyant within a dilute polymer solution is found to be inversely proportional to both the square of the radius of a sphere and the density of the polymer solution. The phase space distribution function for an ensemble of spheres immersed at equilibrium within a dilute polymer solution is found and used to define the magnitude of the ensemble average peculiar acceleration of the spheres. The peculiar acceleration results from changes in direction of the peculiar velocity. It is found to be directly proportional to the temperature, polymer density, and square of the radius of a sphere and inversely proportional to the mass of a sphere. The self‐ diffusivity of the particles varies directly with the square root of the temperature. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009