bluuebunny/crossref_metadata_2025_split huggingface dataset:
Topological Control of Porous Silicon Photonic Crystals by Microcontact Printing
Authors: Ruminski Anne M. , Barillaro Giuseppe , Secret Emilie , Huang Winnie D. , Potocny Andrea , Carion Ulysse , Wertans Charles , Sailor Michael J. 
Published: May 2013

Free‐standing, uniformly wrinkled multilayered photonic crystals are prepared in porous Si by conformal electrochemical etch of a highly doped p++ type Si wafer that is pre‐shaped with periodic grooves. The grooves are prepared by first microcontact printing a parallel line of oligomeric polydimethylsiloxane and then electrochemically etching the patterned wafer. The etch proceeds anisotropically, with the resist‐covered regions etching more slowly than the resist‐free regions. The grooved substrate is then etched using a sinusoidal current density waveform, generating a porosity‐modulated photonic crystal (rugate filter) that is conformal with the grooves. This porous multilayer is then removed, resulting in a freestanding nanostructure with a corrugated topological modulation in the x–y plane and a rugated porosity modulation in the z‐direction. In addition to the resonant photonic reflectance signature from the porosity‐modulated rugate filter (along the z direction), the structures display optical diffraction in transmission from the x–y plane due to the spatially modulated grooves. The silicon wafer that remains after removal of the porous multilayer still contains a rippled surface, allowing the process to be repeated without additional microcontact printing. Six generations of freestanding, three‐dimensional diffraction gratings are produced from a single wafer and only one initial patterning step.
Effects of different ionic liquids on the electrospinning of a polyacrylonitrile polymer solution
Authors: Cheng Wei , Yu Qi , Qiu Zhiming , Yan Yurong 
Published: May 2013

ABSTRACTAdditives have been proven to be useful in improving electrospinnability and controlling fiber morphology through the modification of solution properties, including the conductivity, viscosity, and surface tension. In this study, the effects of adding small amounts of four different types of ionic liquids [i.e., 1‐butyl‐3‐methylimidazolium chloride (C4MIMCl), 1‐dodecyl‐3‐methylimidazolium chloride (C12MIMCl), 1‐ethyl‐3‐methylimidazolium bromide (C2MIMBr), and 1‐ethyl‐3‐methylimidazolium phosphate (C2MIM)3PO4] on the solution properties, electrospinning process, and characteristics of polyacrylonitrile (PAN) were investigated. The results show that the solution conductivities significantly increased with the addition of different ionic liquids with concentrations varying from 0.1 to 1.0 wt %, and the tendency depended on the structures of the ionic liquids. (C2MIM)3PO4 showed the highest conductivity value; this was followed by C2MIMBr, C4MIMCl, and C12MIMCl. The ionic liquids formed visible crystals; this made the fiber surfaces rough, and some fiber segments underwent partial aggregation. A regular varying tendency between the minimum mean diameter of the PAN/ionic liquid fibers and the structure of the ionic liquid was found. The PAN/N,N‐dimethylformamide (DMF)/(C2MIM)3PO4 solution showed the highest conductivity among the four systems with different ionic liquids added, and the thinnest minimum diameter of the PAN/(C2MIM)3PO4 fibers appeared with a relatively low ionic liquid concentration of 0.25 wt %, whereas the PAN/DMF/C12MIMCl solution had the lowest conductivity, and the minimum mean diameter of PAN/C12MIMCl fibers appeared at a relatively high ionic liquid concentration of 0.8 wt %. Although the conductivity of the PAN/DMF/C2MIMBr solution was higher than that of the PAN/DMF/C4MIMCl solution, the minimum mean diameters of the PAN/C2MIMBr and PAN/C4MIMCl fibers appeared at the same ionic liquid concentration of 0.5 wt % because of the similar ionic activities of C2MIMBr and C4MIMCl. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2359–2368, 2013
Preparation, characterization, and release behavior of ceftiofur‐loaded gelatin‐based microspheres
Authors: Hao Zhihui , Wu Haoting , Hao Lihua , Zhao Yongda , Ding Zhaopeng , Yang Fenfang , Qu Baohan 
Published: May 2013

ABSTRACTDrug‐loaded microspheres prepared from biomacromolecules have received considerable interest. In this article, we report a facile method for preparing ceftiofur‐loaded gelatin‐based microspheres for controlled release. We investigated the effects of factors, including the rotational speed, concentration of surfactant, concentration of gelatin, and ratio of water to oil (W/O), on the morphologies of gelatin microspheres and obtained the optimized conditions; for a typical average diameter of about 15 μm, these were 1000 rpm, a concentration of span 80 of 2.0%, a gelatin concentration of 20%, and a W/O of 1:20. Gelatin microspheres loaded with ceftiofur, ceftiofur‐Na, and ceftiofur‐HCl were prepared and characterized by scanning electron microscopy and laser light scattering. In vitro release studies were carefully performed for microspheres prepared with different crosslinker contents, loaded with different drugs, and blended with chitosan. The loaded ceftiofur showed an obviously longer release time compared with pure ceftiofur powder. A higher content of crosslinker led to a longer release time, but when the content reached 5%, the microspheres had a significantly cracked surface. The results also indicate that the blending of a small amount of chitosan could greatly prolong the release time. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2369–2376, 2013
Stability of a chitosan layer deposited onto a polyethylene surface
Authors: Pâslaru Elena , Fras Zemljic Lidija , Bračič Matej , Vesel Alenka , Petrinić Irena , Vasile Cornelia 
Published: May 2013

ABSTRACTA two‐step procedure was applied to obtain antimicrobial films; this procedure involved a corona treatment of the polyethylene (PE) surface and its chemical activation with 1‐ethyl‐3‐[3‐dimethylaminopropyl] carbodiimide hydrochloride and N‐hydroxysuccinimide, and this led to the covalent bonding of chitosan on the PE surface. Electrochemical methods were used to investigate the stability of the deposited chitosan layer. The potentiometric and polyelectrolyte titrations showed that some amount of chitosan desorbed faster from the surface until equilibrium was reached and also that the grafted chitosan layer was more stable than the physically adsorbed one. The chitosan immobilized on the PE surface exhibited the expected antibacterial activity when tested against three bacteria, which included two Gram‐negative bacteria, Salmonella enteritidis and Escherichia coli, and one Gram‐positive bacterium, Listeria monocytogenes. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2444–2457, 2013
Development of magnetic fabrics with tunable hydrophobicity
Authors: Ho Thu , Ghochaghi Negar , Tepper Gary 
Published: May 2013

ABSTRACTPolystyrene (PS) fiber mats incorporating iron (Fe) particles were fabricated by electrospinning and the hydrophobicity of the resulting magnetic fabrics was investigated with and without an applied magnetic field. The results show that the hydrophobicity increases in the presence of a magnetic field and the hysteresis in the advancing/receding contact angle decreases in the presence of a magnetic field. It is also shown that the contact angle and hysteresis increase with decreasing fiber diameter. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2352–2358, 2013
Preparation and characterization of bamboo fiber‐graft‐lauryl methacrylate and its composites with polypropylene
Authors: Chen Qinhui , Mao Xinggong , Xue Hanyu , Deng Yi , Lin Jinhuo 
Published: May 2013

ABSTRACTIn this study, lauryl methacrylate grafted onto bamboo fibers (BF‐g‐LM) was prepared to improve the interfacial compatibility between hydrophilic bamboo fibers (BFs) and hydrophobic plastic. The lauryl methacrylate (LM) was initiated by benzoxyl peroxide (BPO) and grafted onto BFs via a free‐radical chain‐transfer reaction. LM was grafted onto BFs with ether bonds, and differential scanning calorimetry indicated that the ether pyrolysis of BF‐g‐LM occurred at 280°C. The optimum preparation conditions were obtained as follows: 0.30 g of pretreated bamboo flour was immersed in 0.225 mol/L LM. The reaction was then initiated by 0.025 mol/L BPO, and this reaction was sustained for 4 h at 80°C. BF‐g‐LM served as coupling agent between the BFs and the polypropylene (PP) matrix, as shown by scanning electron microscopy analysis. The elongation at break of the BF/PP composites with BF‐g‐LM increased to two times compared to that of the BF/PP composites without BF‐g‐LM. The impact strength and maximum deflection also increased to 75 and 580%, respectively. In conclusion, BF‐g‐LM is a promising coupling agent that can be used in BF‐reinforced thermoplastic composites. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2377–2382, 2013
Gas permeability of thin dense films from polymer blend of thermoplastic elastomer and polyolefin
Authors: Uenishi Masamoto , Fukushima Noriaki , Teramachi Masashi , Mizuta Masahiko , Kamo Jun , Tsuru Toshinori 
Published: May 2013

ABSTRACTStretched thin films composed of a thermoplastic elastomer, a polystyrene‐block‐poly(ethylene butylene)‐block‐polystyrene triblock copolymer (SEBS), and polyolefins, poly(ethylene‐co‐ethylacrylate) and poly(ethylene‐co‐propylene), were obtained by blow‐molding, uniaxial stretching, and cooling to room temperature and the gas permeability of the stretched films was investigated. When the as‐blown annealed film was subjected to uniaxial stretching in the machine direction, PO2 and PN2 increased with an increase in the stretching ratio K and approached a constant value at high stretching ratios. In addition, PO2/PN2 decreased gradually with K and approached a value of 2.95–3.0. The reason for this unique gas permeation behavior is that the molecular mobility of poly(ethylene butylene) chains in a direction normal to the film increases and reaches an equilibrium state at around K = 4.5. The change in gas permeability of the stretched films can be explained using a deformation model for the SEBS matrix. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39386.
Large‐scale equal‐proportional amplification bio‐replication of shark skin Based on solvent‐swelling PDMS
Authors: Chen Huawei , Zhang Xin , Zhang Deyuan , Pan Junfeng , Hagiwara Ichiro 
Published: May 2013

ABSTRACTShark skin has attracted worldwide attention on its superior drag reduction, so‐called shark skin effect. Such marvelous function of shark skin, in particular, is in part related to complicated micro‐riblets. As the creation of natural evolution, micro‐riblets of shark skin act out desirable drag reduction only within range of swimming speed. Over past few years, bio‐replication approach which takes the shark skin as replica template to 1 : 1 transfer surface morphology has been widely applied for drag reduction. However, if application environment remarkably differs from living environment, the drag reduction function is attenuated or even becomes adverse, i.e., the surface structure nonadjustable to ambient environment is obstacle to widespread application of bio‐replication. In this paper, large‐scale equal‐proportional amplification bio‐replication approach is presented to adjust the micro‐riblets of shark skin by taking solvent‐swelling polymer as replica mould. Solvent‐swelling property of polymer is investigated by controlling its swelling ratio to make natural surface function adapting to various application environment. Apart from higher replication accuracy about 95%, experiments show that about 140% solvent‐swelling ratio is achieved at one‐time amplification, and translation of drag reduction peak of natural surface function form living environment to various application environments is ensured by successive large‐scale equal‐proportional bio‐replications. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2383–2389, 2013
Chemical and structural characterization of alkaline‐extractable hemicelluloses from various eucalyptus species
Authors: Wei Wen‐bang , Li Li‐na , Chang Liang , Wang Zheng 
Published: May 2013

ABSTRACTEucalyptus species are currently one of the main feedstock for pulping and papermaking industry in China. In the present study, alkali‐extractable hemicelluloses were isolated from different eucalyptus species (Eucalyptus camaldulensis, E. urophylla × grandis, and E. urophylla × E. tereticornis) at mild conditions prior to pulping. Structural characterization of these hemicellulosic polymers based on monosaccharide, molecular weight, Fourier transform infrared, 1H, 13C, and two‐dimensional heteronuclear single quantum coherence nuclear magnetic resonance analysis revealed that these alkali‐extractable polysaccharides shared the common structure composed of the (1→4)‐linked‐β‐D‐xylopyranosyl backbone with 4‐O‐methyl‐α‐D‐glucuronic acid attached to O‐2 of the xylose residues. The potential structures of the alkali‐extractable hemicelluloses were proposed based on the comprehensive analysis. The well‐characterized structures of these hemicelluloses could enlarge the industrial application of these hemicelluloses from the Eucalyptus species in a biorefinery process. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2390–2398, 2013
Synergistic effects by compatibilization and annealing treatment of metallocene polyethylene/PLA blends
Authors: Lai Sun‐Mou , Hung Kun‐Che , Kao Hui Cheng , Liu Liang‐Chuan , Wang Xue Fen 
Published: May 2013

ABSTRACTThe properties of metallocene polyethylene (mPE)/polylactic acid (PLA) bio‐based blends containing an ethylene‐glycidyl methacrylate‐vinyl acetate (EGMA‐VA) compatibilizer, with or without the annealing effect of PLA were investigated. The results from SEM (Scanning electron microscope) morphology observation revealed that the dispersed PLA particles sizes within the mPE matrix tended to decrease with the added compatibilizer due to the enhanced interfacial interaction. DSC (Differential scanning calorimetry) and XRD (X‐ray diffractometer) results indicated that the addition of the compatibilizer completely hindered the cold crystallization and rearrangement crystallization of PLA, even though the additional annealing effect tended to increase the crystallization of PLA. Tensile test results showed the synergistic effects by compatibilization and annealing treatment improved the tensile strength and Young's modulus, up to 38 % and 62 % increase, respectively. With the incorporation of the compatibilizer, the viscosity increased and reached the highest level among all neat resins and blends, which was attributed to the enhanced interfacial interaction between mPE and PLA. Hopefully, the incorporated bio‐based PLA materials could be helpful in reducing the use of petroleum‐based materials and are beneficial to the environment in terms of the sustainable development concern. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2399–2409, 2013
Modification of vital wheat gluten with phosphoric acid to produce high free swelling capacity
Authors: Robertson George H. , Cao Trung K. , Gregorski Kay S. , Hurkman William J. , Tanaka Charlene K. , Chiou Bor‐Sen , Glenn Gregory M. , Orts William J. 
Published: May 2013

ABSTRACTWheat gluten reacts with phosphoric acid in the presence of urea to produce natural superabsorbent gels. Fourier Transform Infra‐red (FT‐IR) spectroscopy and two‐dimensional gel electrophoresis (2DE) reveal chemical changes from the reaction. Temperatures above 120°C and dry conditions create the opportunity for reaction. FT‐IR analyses confirm the formation of esters, carbamates, and phosphoramides on the gluten samples. 2DE protein composition topographies indicate a shift in the isoelectric point (pI) to lower values along with extensive inter‐protein linkages. A free swelling capacity (FSC) in excess of 85× the mass of the converted gluten is obtainable using a conservative vacuum‐assisted method to recover and quantify the properties of the wet gel. Other methods produce FSC values nearly twice as high. FSC for acid‐treated gluten is lower for solutions containing solutes than the FSC for deionized water. Native gluten produces FSC values that are about 2% of those for treated gluten, but these values are less sensitive to the presence of ionic solutes and increase slightly in the presence of aqueous ethanol up to a mole fraction of 0.25.. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39440.
Synthesis and characterization of fullerene functionalized poly(vinyl chloride) (PVC) and dehydrochlorinated PVC using atom Transfer Radical Addition and AIBN based fullerenation
Authors: Seeponkai Narumon , Wootthikanokkhan Jatuphorn , Thanachayanont Chanchana 
Published: May 2013

ABSTRACTThe research presented details chemical modifications of poly(vinyl chloride) (PVC) and its derivative, dehydrochlorinated PVC (DH‐PVC) through the use of two grafting techniques, namely a normal fullerenation, using AIBN (2,2′‐Azoisobutyronitrile), and the atom transfer radical addition (ATRA). The products were characterized and the presence of new FTIR peaks at 528 and 577 cm−1 along with new 1H‐NMR signal at 3.9 ppm, suggested that fullerenes has been grafted to the polymer molecules. Percentage of C60 in the fullerene grated products determined by UV/Visible spectroscopy initially increased with the amount of fullerene used to a maximum value (∼5.66 % wt) before decreasing again. It was also determined that the C60 content of the fullerene grafted PVC product prepared by using ATRA, was notably greater than that obtained using the normal fullerenation approach, regardless of the amount of C60 used. When the dehydrochlorinated PVC was used as the starting polymer for fullerenation, the fullerene grafted DH‐PVC using ATRA, was markedly insoluble in many common solvents (THF and dichlorobenzene). This was not the cases for the fullerene grafted DHPVC prepared via an AIBN based fullerenation. Furthermore, the electrical conductivity values of the modified PVC products determined by using a four‐point probe method were found to increase linearly with the amount of C60 present. Overall our data suggest that the suitable and efficient techniques for grafting C60 onto PVC and DHPVC chains are ATRA and AIBN‐based fullerenation, respectively. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2410–2421, 2013
Preparation and characterization of potassium nitrate controlled‐release fertilizers based on chitosan and xanthan layered tablets
Authors: Melaj Mariana A. , Daraio Marta E. 
Published: May 2013

ABSTRACTSolid polymeric matrices based on xanthan and chitosan and using KNO3 as a model agrochemical were prepared by direct compression, with a view to evaluating their potential as controlled‐release fertilizers (CRFs). The swelling behavior, surface characteristics, and durability in soil of the tablets were studied. The release data were treated with a power law model in order to understand the delivery kinetics of KNO3. This proved to be non‐Fickian diffusion, with release exponents ranging from 0.80 to 0.88, highlighting the importance of polymer relaxation on drug release. The presence of drug‐free surface layers was an important factor in modulating the release. When comparing experiments without and with stirring, the release time ratios between them were as high as 40, predicting a significantly greater release time in soils. In durability experiments in soil, the polymeric matrices lasted longer than 6 weeks. These results show that layered xanthan and xanthan–chitosan matrices perform as a promising system for developing CRFs. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2422–2428, 2013
Entanglement network of chitin and chitosan in ionic liquid solutions
Authors: Horinaka Jun‐ichi , Urabayashi Yuhei , Takigawa Toshikazu , Ohmae Masashi 
Published: May 2013

ABSTRACTConcentrated solutions of a chitin from squid pens and of two commercial samples of chitosan were successfully prepared by using an ionic liquid 1‐butyl‐3‐methylimidazolium acetate as a solvent. The dynamic viscoelasticity data for the solutions exhibited rubbery plateaus, indicating the existence of entanglement network of chitin and chitosan in the solutions. To characterize the network, the values of the molecular weight between entanglements (Me) for chitin and chitosan in the solutions were determined from the plateau moduli. Then the values of Me in the molten state (Me,melt), a material constant reflecting the inherent nature of polymer species, for chitin and chitosan were estimated to be 1.7 × 103 and 3.0 × 103, respectively. It was found that there was a significant difference in Me,melt between chitin and chitosan. Compared with other polysaccharides such as cellulose and agarose in terms of the number of monosaccharide units between entanglements (Nunit), chitin had significantly smaller Nunit of 8, while chitosan had equivalent Nunit of 19. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2439–2443, 2013
Investigation of the effects of adhesion promoters on the adhesion properties of rubber/steel cord by a new testing technique
Authors: Shi Xinyan , Ma Mingqiang , Lian Chengbo , Zhu Dawei 
Published: May 2013

ABSTRACTThe effects of adhesion promoters, cobalt decanoate and PN759 (modified resorcinol) on the static and dynamic adhesion properties of rubber/steel cord in a carcass recipe are examined. A new testing method with special rubber/steel cord specimens was developed. It was found that cobalt decanoate could improve the static adhesion and favored the dynamic adhesion of rubber/steel cord so that adhesive failure mainly occurred in rubber phase. A resorcinol‐formaldehyde‐silica promoting system was deleterious to adhesion stability, but improved initial adhesion strength. PN759 improved the dynamic mechanical properties compared with resorcinol for the carcass vulcanizates at strains less than 10%. PN759 instead of resorcinol slightly improved the static and dynamic adhesion and the probability that adhesion failure occurred in the interphase was similar to that occurring in the rubber phase. The dynamic “pull‐out forces” for samples with 1.0 phr cobalt decanoate first increased and then decreased with the increase in the number of fatigue cycles and reached a maximum at 100,000 fatigue cycles. The covered rubber on the “pulled‐out” cord after fatigue appeared to form a screw thread form and the greater pull‐out force corresponded to more uniform and narrower screw threads. SEM images indicated that un‐dispersed filler agglomerates could be the initiating factor for adhesive failure. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39460.