bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of pretreatment on shear strength of various wood species
Authors: Uysal Burhanettin 
Published: January 2006

AbstractA study was conducted to determine the effects of wood pretreatment on the bonding strength of wood materials. The woods used for the test samples (based on BS EN 204) were oriental beech (Fagus orientalis Lipsky), Scotch pine (Pinus sylvestris L.), oak (Quercus petreae Liebl.), and chestnut (Castanea sativa Mill.). They were impregnated with Tanalith‐C, creosote, and Protim 230 WR–paraffin by full‐cell methods according to ASTM D 1413‐76 standards and the directions of the manufacturers. After impregnation, shear strength tests (based on BS EN 205) were applied on the samples bonded with poly(vinyl acetate) (PVAc), Desmodur‐VTKA, and Pattex fast. The highest shear strength was obtained in nonimpregnated (control) and PVAc‐D1 glued oak (5.328 N/mm2), and the lowest shear strength was obtained in Protim 230 WR–paraffin and Pattex fast glued chestnut (0.169 N/mm2). Accordingly, the impregnation process negatively affected the adhesive bonding strength. Impregnation chemicals, especially containing oily or similar substances, could not be proposed for wood elements exposed to shear strength. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 245–252, 2006
Analysis of the structural characteristics of nanoscale silk particles
Authors: Li Y. , Yuen C. W. M. , Hu J. Y. , Cheng Y. F. 
Published: January 2006

AbstractNanoscale silk particles were prepared from silk fibers by a special pretreatment with the aid of specially designed machinery and techniques. Scanning electron micrographs showed that the particle sizes of the silk powders produced from silk fibers around 9–11 μm in diameter decreased from a microscale to a nanoscale after three stages of pulverization, and this was further confirmed with a laser particle size analyzer. Fourier transmission infrared analysis showed that there were no substantial changes in the chemical structure of the silk after the pulverization processes. The silk powders after the second and third pulverizations slightly differed from that of the silk fiber and the particles after the first pulverization with a greater amount of the primary aliphatic amines. Also, there were secondary amides present in the silk fiber and the powders after the first and second pulverizations but absent in the powders after the third pulverization. Moreover, the silk powders after the third pulverization had a greater number of C(CH3)3 groups than the silk fibers and the powders after the first and second pulverizations. X‐ray diffraction analysis showed that the crystallinity of the silk powders decreased when the particle sizes decreased, particularly to nanoscales. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 268–274, 2006
Synthesis and photoinitiation properties of a novel quaternary ammonium tetraphenylborate salt
Authors: Yu Xueya , Chen Jia , Yang Jianwen , Zeng Zhaohua , Chen Yonglie 
Published: January 2006

AbstractQuaternary ammonium salts are photobase generators. Recently, we prepared a novel quaternary ammonium tetraphenylborate salt bearing a 6‐methoxynaphthoylmethyl group. The structure of the products was confirmed by elemental analysis and 1H‐NMR. Thermogravimetry showed its good thermostability. UV spectra and fluorescence emission spectra of the samples were studied. A mass spectrometry method for the analysis of the tertiary amine and other fragments produced by photolysis was established. Photolysis was found to produce both tertiary amine and free radicals. Therefore, the products of photolysis not only could cause thermal curing of epoxide but also could initiate the free‐radical polymerization of acrylate or methyl acrylate monomer. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 399–405, 2006
Structured radiation‐grafted polymer films and membranes
Authors: Rager Timo 
Published: January 2006

AbstractThe patterning of radiation‐grafted polymer films and membranes on a 1‐mm scale was investigated as a means of improving the mechanical properties of these materials. Stress–strain measurements indicated that no positive effect was achieved. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 292–294, 2006
Blue‐light‐emitting poly(arylene ethynylenes) containing alternating sequences of biphenylene or fluorenediyl and p‐phenylene moieties linked through triple bonds
Authors: Joo Sung‐Hoon , Jeong Mi‐Yun , Ko Doo Hyun , Park Jong‐Hyun , Kim Ki Yong , Bae Sung Joon , Chung In Jae , Jin Jung‐Il 
Published: January 2006

AbstractTwo new poly(arylene ethynylenes) were synthesized by the reaction of 1,4‐diethynyl‐2.5‐dioctylbenzene either with 4,4′‐diiodo‐3,3′‐dimethyl‐1,1′‐biphenyl or 2,7‐diiodo‐9,9‐dioctylfluorene via the Sonogashira reaction, and their photoluminescence (PL) and electroluminescence (EL) properties were studied. The new poly(arylene ethynylenes) were poly[(3,3′‐dimethyl‐1,1′‐biphenyl‐4,4′‐diyl)‐1,2‐ethynediyl‐(2,5‐dioctyl‐1,4‐phenylene)‐1,2‐ethynediyl] (PPEBE) and poly[(9,9‐dioctylfluorene‐2,7‐diyl)‐1,2‐ethynediyl‐(2,5‐dioctyl‐1,4‐phenylene)‐1,2‐ethynediyl] (PPEFE), both of which were blue‐light emitters. PPEBE not only emitted better blue light than PPEFE, but it also performed better in EL than the latter when the light‐emitting diode devices were constructed with the configuration indium–tin oxide/poly(3,4‐ethylenedioxythiophene) doped with poly(styrenesulfonic acid) (50 nm)/polymer (80 nm)/Ca:Al. The device constructed with PPEBE exhibited an external quantum efficiency of 0.29 cd/A and a maximum brightness of about 560 cd/m2, with its EL spectrum showing emitting light maxima at λ = 445 and 472 nm. The device with PPEFE exhibited an efficiency of 0.10 cd/A and a maximum brightness of about 270 cd/m2, with its EL spectrum showing an emitting light maximum at λ = 473 nm. Hole mobility (μh) and electron mobility (μe) of the polymers were determined by the time‐of‐flight method. Both polymers showed faster μh values. PPEBE revealed a μh of 2.0 × 10−4 cm2/V·s at an electric field of 1.9 × 105 V/cm and a μe of 7.0 × 10−5 cm2/V·s at an electric field of 1.9 × 105 V/cm. In contrast, the mobilities of the both carriers were slower for PPEFE, and its μh (8.0 × 10−6 cm2/V·s at an electric field of 1.7 × 106 V/cm) was 120 times its μe (6.5 × 10−8 cm2/V·s at an electric field of 8.6 × 105 V/cm). The much better balance in the carriers' mobilities appeared to be the major reason for the better device performance of PPEBE than PPEFE. Their highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels were also a little different from each other. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 299–306, 2006
Interpenetrating polymer networks of poly(butyl methacrylate) and poly(α‐terpineol‐co‐styrene): Synthesis and characterization
Authors: Pathak Shalini , Srivastava A. K. 
Published: January 2006

AbstractSimultaneous interpenetrating polymer networks (IPNs) based on poly(butyl methacrylate) and poly(α‐terpineol‐co‐styrene) were synthesized with azobisisobutyronitrile (AIBN) as the initiator and divinyl benzene as the crosslinking agent in xylene under an inert nitrogen atmosphere. Fourier transform infrared spectra provided structural evidence for the IPNs, indicating characteristic frequencies of ester groups of butyl methacrylate at 1723 cm−1 and alcoholic groups of α‐terpineol at 3436 cm−1. Scanning electron microscopy revealed threadlike network structures. Properties such as percentage swelling and average molecular weight between crosslinks were direct functions of the copolymer and initiator (AIBN) concentrations and inverse functions of the monomer (butyl methacrylate) and crosslinking agent (divinyl benzene) concentrations. Differential scanning calorimetry showed an IPN glass‐transition temperature at 80.2°C. The thermal decompositions of the IPNs were established with the help of thermogravimetric analysis. The value of the activation energy, calculated from thermogravimetric analysis with the Coats and Redfern equation, was 23 kJ/mol. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 343–352, 2006
Characterization and photoluminescence properties of diglycidyl methacrylic resin doped with the Eu3+–β‐diketonate complex
Authors: Parra D. F. , Mucciolo A. , Duarte D. G. , Brito H. F. , Lugão A. B. 
Published: January 2006

AbstractTriaquatris(acetyl acetonate)europium(III) [Eu(acac)3] at 1, 5, 10, and 15% was doped in diglycidyl methacrylic (DGMA) resin, and their luminescent properties in the solid state are reported. These systems were characterized with elemental analysis, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy. On the basis of TGA data, the thermal stability of the DGMA/Eu(acac)3x% system was similar to that of the polymer, except at the highest concentration (15%). The DSC results indicated that the new systems were chemically stable and underwent the cure process before decomposition. The emission spectra of the Eu3+/acetyl acetonate complex doped in DGMA, recorded at 298 and 77 K, exhibited the characteristic bands arising from the 5D0→7FJ transitions (J = 0–4). The luminescence intensity decreased with an increasing precursor concentration in the doped polymer. The system doped at a low concentration (1% Eu3+ complex) presented more luminescence efficiency than those doped at 5, 10, and 15%. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 406–412, 2006
Natural rubber/poly(ethylene‐co‐vinyl acetate)‐blend‐based nanocomposites
Authors: Sharif Jamaliah , Yunus Wan Md Zin Wan , Dahlan Khairulzaman Hj , Ahmad Mansor Hj 
Published: January 2006

AbstractNatural rubber (NR)/poly(ethylene‐co‐vinyl acetate) (EVA) blend–clay nanocomposites were prepared and characterized. The blend nanocomposites were prepared through the melt mixing of NR/EVA in a ratio of 40/60 with various amounts of organoclay with an internal mixer followed by compression molding. X‐ray diffraction patterns revealed that the nanocomposites formed were intercalated. The formation of the intercalated nanocomposites was also indicated by transmission electron microscopy. Scanning electron microscopy, used to study the fractured surface morphology, showed that the distribution of the organoclay in the polymer matrix was homogeneous. The tensile modulus of the nanocomposites increased with an increase in the organoclay content. However, an increase in the organoclay content up to 5 phr did not affect the tensile strength, but the organoclay reduced this property when it was increased further. This study also indicated that a low silicate content dispersed in the blend matrix was capable of increasing the storage modulus of the material. The addition of the organoclay also increased the decomposition temperature of the NR/EVA blends. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 353–362, 2006
4‐chloro‐3‐methylphenyl methacrylate copolymers with 2,4‐dichlorophenyl methacrylate: Synthesis, characterization, and antimicrobial activity
Authors: Patel Jatin N. , Dolia Mitul B. , Patel Mitesh B. , Patel Rajni M. 
Published: January 2006

Abstract4‐Chloro‐3‐methylphenyl methacrylate (CMPM) and 2,4‐dichlorophenyl methacrylate (2,4‐DMA) were synthesized by reacting methacryloyl chloride with 4‐chloro‐3‐methylphenol (CMP) and 2,4‐dichlorophenol (2,4‐DP), respectively. Homo and copolymers of CMPM and 2,4‐DMA were obtained from different monomer feed ratios, using 2,2′‐azobisisobutyronitrile as initiator in toluene at 70°C. IR‐spectroscopy was employed to characterize the resulting homo and copolymers. Copolymer compositions were determined by ultraviolet (UV) spectroscopy. Fineman–Ross method was used to calculate the reactivity ratios of the monomers. Average molecular weight and polydispersity index were obtained by gel permeation chromatography (GPC). Thermogravimetric analyses (TGA) and differential thermal analysis (DTA) of copolymers were carried out under a nitrogen atmosphere. Antimicrobial effects of the homo and copolymers were also investigated for various microorganisms such as bacteria, fungi, and yeast. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100:439–448, 2006
Modification of unsaturated polyester resin by polyurethane prepolymers
Authors: Cherian A. Benny , Abraham Beena T. , Thachil Eby Thomas 
Published: January 2006

AbstractUnsaturated polyester resins (UPRs) are extensively used by the fiber‐reinforced plastic (FRPs) industry. These resins have the disadvantages of brittleness and poor resistance to crack propagation. In this study, UPRs were chemically modified by reactive blending with polyurethane prepolymers having terminal isocyanate groups. Hybrid networks were formed by copolymerisation of unsaturated polyesters with styrene and simultaneous reaction between terminal hydroxyl groups of unsaturated polyester and isocyanate groups of polyurethane prepolymer. The prepolymers were based on toluene diisocyanate (TDI) and each of hydroxy‐terminated natural rubber (HTNR), hydroxy‐terminated polybutadiene (HTPB), polyethylene glycol (PEG), and castor oil. Properties like tensile strength, toughness, impact resistance, and elongation‐at‐break of the modified UPRs show considerable improvement by this modification. The thermal stability of the copolymer is also marginally better. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 449–456, 2006
Epoxidized phenolic novolac: A novel modifier for unsaturated polyester resin
Authors: Cherian A. Benny , Thachil Eby Thomas 
Published: January 2006

AbstractUnsaturated polyester resins (UPRs) are used widely in the fiber‐reinforced plastics (FRPs) industry. These resins have the disadvantages of brittleness and poor resistance to crack propagation. In this study, hybrid polymer networks (HPNs) based on UPR and epoxidized phenolic novolacs (EPNs) were prepared by reactive blending. A HPN is composed of a backbone polymer containing two types of reactive groups that can take part in crosslinking reactions via different mechanisms. EPNs were prepared by glycidylation of novolacs using epichlorohydrin. The novolacs had varying phenol: formaldehyde ratios. Blends of unsaturated polyester with EPN were then prepared. The physical properties of the cured blends were compared with those of the control resin. EPN shows good miscibility and compatibility with the resin and improves the toughness and impact resistance substantially. Considerable enhancement of tensile strength is also noticed at about 5% by weight of epoxidized novolac resin. TGA, DMA, and DSC were used to study the thermal properties of the toughened resin and the fracture behavior was studied using SEM. The blends are also found to have better thermal stability. Blending with EPN can be a useful and cost‐effective technique for modification of UPR. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 457–465, 2006
Preparation of high‐molecular‐weight poly(L‐lactic acid)‐based polymers through direct condensation polymerization in bulk state
Authors: Kim Hun Sik , Hwang Mi Ok , Kim Mal Nam , Yoon Jin San 
Published: January 2006

AbstractPoly(L‐lactic acid‐co‐succinic acid‐co‐1,4‐butanediol) (PLASB) was synthesized by a direct condensation copolymerization of L‐lactic acid, succinic acid (SA), and 1,4‐butanediol (BD) in bulk state using titanium(IV) butoxide (TNBT) as a catalyst. Weight average molecular weight (Mw) of PLASB increased from 3.5 × 104 to 2.1 × 105 as the content of SA and BD went up from 0.01 to 0.5 mol/100 mol of L‐lactic acid (LA). PLASB having Mw in the range from 1.8 × 105 to 2.1 × 105 showed tensile properties comparable to those of commercially available poly(L‐lactic acid) (PLLA). In sharp contrast, homopolymerization of LA in bulk state produced PLLA with Mw as low as 4.1 × 104, and it was too brittle to prepare specimens for the tensile tests. Mw of PLASB synthesized by using titanium(IV)‐2‐ethyl(hexoxide), indium acetate, indium hydroxide, antimony acetate, antimony trioxide, dibutyl tin oxide, and stannous‐2‐ethyl 1‐hexanoate was compared with that of PLASB obtained by TNBT. Ethylene glycol oligomers with different chain length were added to LA/SA in place of BD to investigate effect of chain length of ethylene glycol oligomers on the Mw of the resulting copolymers. Biodegradability of PLASB was analyzed by using the modified Sturm test. Toxicity of PLASB was evaluated by counting viable cell number of mouse fibroblast cells that had been in contact with PLASB discs. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 466–472, 2006
Differential scanning calorimetry of urea–formaldehyde adhesive resins, synthesized under different pH conditions
Authors: Park Byung‐Dae , Kang Eun‐Chang , Park Jong Young 
Published: January 2006

AbstractThe purpose of this study was to investigate the effects of reaction pH conditions on thermal behavior of urea–formaldehyde (UF) resins, for the possible reduction of formaldehyde emission of particleboard bonded with them. Thermal curing properties of UF resins, synthesized at three different reaction pH conditions, such as alkaline (pH 7.5), weak acid (pH 4.5), and strong acid (pH 1.0), were characterized with multiheating rate method of differential scanning calorimetry. As heating rate increased, the onset and peak temperatures increased for all three UF resins. By contrast, the heat of reaction (ΔH) was not much changed with increasing heating rates. The activation energy (Ea) increased as the reaction pH decreased from alkaline to strong acid condition. The formaldehyde emission of particleboard was the lowest for the UF resins prepared under strong acid, whereas it showed the poorest bond strength. These results indicated that thermal curing behavior was related to chemical species, affecting the formaldehyde emission, while the poor bond strength was believed to be related to the molecular mobility of the resin used. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 422–427, 2006
A conducting nanocomposite of acetylene black with preformed poly‐N‐vinylcarbazole crosslinked by anhydrous FeCl3
Authors: Maity Arjun , Biswas Mukul 
Published: January 2006

AbstractA conducting nanocomposite of crosslinked poly‐N‐vinylcarbazole (CLPNVC) with nanodimensional acetylene black (AB) was prepared by oxidative crosslinking of preformed PNVC through pendant carbazole moieties in presence of anhydrous FeCl3 as an oxidant and AB suspension in CHCl3 medium at 65°C. The incorporation of CLPNVC moieties in the CLPNVC‐AB composite was endorsed by Fourier transform infrared analysis. Scanning electron microscopic analysis showed formation of lumpy aggregates with average sizes in the 130–330 nm ranges. The thermal stability of the CLPNVC‐AB composite was appreciably higher than that of the PNVC‐AB composite. The direct current conductivities of the composites were significantly enhanced relative to that of the PNVC homopolymer (10−12–10−16 S/cm) and varied in the range of 10−4–10−2 S/cm depending on the amount of AB loading in the CLPNVC‐AB composite. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 819–824, 2006
Thermal and mechanical behavior of unsaturated polyesters filled with phase change material
Authors: Çaylı Gökhan , Küsefoğlu Selim 
Published: January 2006

AbstractSamples of commercial unsaturated polyester (UPE) resin, filled with phase‐changeable fillers (PCMs), were prepared, and the thermal and mechanical properties of the cured samples were examined. Fillers chosen were paraffin and Wood's metal. Samples were prepared by making dispersions of these fillers in liquid unsaturated polyester followed by curing with methyl ethyl ketone peroxide (MEKP) and conaphtanate and rigid thermoset samples filled with PCM particles were obtained. The thermal and mechanical behaviors of such a filled composite around the melting points of fillers are very interesting. Effects of varying proportions of PCM on mechanical and thermal properties of final products were examined. The samples show thermal melting behavior without undergoing a change in physical state. Decreases in the maximum working temperature from 75 to 53°C for metal‐filled samples and from 75 to 43°C for paraffin‐filled samples were observed by using dynamic mechanical thermal analysis. Differential scanning calorimetry indicated that heat absorption of paraffin samples were higher than that of metal‐filled samples. For paraffin‐filled samples, heats of fusion were 3.44 cal/g for 10% filled sample and 6.35 cal/g for 20% filled sample. For Wood's metal‐filled samples, heats of fusion were 1.18 cal/g for 10% metal‐filled sample and 1.54 cal/g for 20% metal‐filled sample. Surface hardness was tested with Shormeter D. Surface hardness of metal‐filled composites varied from 86 to 34 shore D at 21°C and 80.6 to 35 shore D at 80°C. For paraffin‐filled samples, surface hardness changed from 86 to 42 shore D at 21°C and from 80.6 to 13 shore D. Morphology of the samples was determined by scanning electron microscopy, of the crack surfaces. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 832–838, 2006
Studies on chemically modified hen egg white and gelatin composites
Authors: Venkateswarlu U. , Boopalan Kamala , Mohan R. , Das B. N. , Sastry T. P. 
Published: January 2006

AbstractHen egg white (A) and gelatin (G) composites at different proportions were prepared and optimized by their stress–strain behavior. The optimized composite (AG) was graft copolymerised with methyl methacrylate (MMA). The AG and its graft copolymer AGMMA were characterized for their mechanical strength, water absorption capacity, Fourier transform infrared spectra, and circular dichroism (CD) spectroscopy. It was evident from the results that AGMMA possesses higher mechanical strength and lower water absorption capacity than does AG. The FTIR spectra of AG and AGMMA confirm the grafting phenomena of MMA onto AG, and the CD spectrum of AG shows two negative bands at around 207 and 222 nm and a positive band at around 191.76 nm, which confirms the α‐helix in the composite. The α‐helical structure in AG was broken and converted into unordered random coil in AGMMA because of the reaction conditions while grafting MMA onto AG, which was confirmed by the increase in mechanical strength of AGMMA. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 318–322, 2006
Structure and properties of polyimide‐bonded magnets processed from prepolymers based on diacetyl derivatives of aromatic diamines and dianhydrides
Authors: Yudin V. E. , Otaigbe J. U. , Bui Tho X. , Svetlichnyi V. M. 
Published: January 2006

AbstractWe report a novel method of polyimide (PI) synthesis from prepolymers based on dianhydrides and diacetyl derivatives of aromatic diamines that facilitate the preparation of a melt processable mixture at 300 ± 10°C of the prepolymer and magnetic Nd‐Fe‐B alloy to provide PI‐bonded magnets with enhanced properties. It is shown that chemical structure of the prepolymers strongly influences viscosity behavior via crystallization of the oligoimide in the melt, leading to formation of PI with rigid‐rod like structure. This structural ordering of the prepolymers based on diacetyl derivative of diamine used in this study, if not controlled, leads to exponential increase of melt viscosity with time, making it practically impossible to prepare melt processable mixture of the magnetic particles and the PI prepolymers at elevated temperatures. The results obtained demonstrate that appropriate dianhydrides and diacetyl derivatives of diamines that do not lead to crystallization of oligoimides in prepolymer mixture can be used under controlled processing conditions to prepare melt‐processable PI‐bonded magnets containing rigid‐rod like PI structure that significantly increases thermal stability of the magnets. The temperature dependencies of the magnetic properties of the PI‐bonded magnets under conditions that they are likely to encounter during their service life were found to be remarkably similar to that of commercial thermoplastic magnets such as injection‐molded nylon magnets. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 478–485, 2006