bluuebunny/crossref_metadata_2025 huggingface dataset:
Dyeing properties of Bombyx mori silks grafted with methyl methacrylate and methacrylamide
Authors: Prachayawarakorn Jutarat , Kryratsamee Watthana
Published: January 2006

To improve their dyeing and colorfastness properties, degummed Bombyx mori silks were chemically modified by a grafting technique with either methyl methacrylate (MMA) monomer or methacrylamide (MAA) monomer. Both commercial synthetic dyes, that is, acid and basic dyes, and natural dyes extracted from turmeric, without and with potassium aluminum sulfate mordant, were used in this study. Percentage dye uptake increased with the presence of poly(methyl methacrylate) or polymethacrylamide in the silk fibroin structure regardless of the types of the dyestuffs. Furthermore, compared to the degummed silk, the colorfastness to washing of the MMA‐grafted and MAA‐grafted silks dyed with acid, basic, and curcumin dyestuffs were greatly improved. Colorfastness to both acid and basic perspirations with acid and basic dyestuffs was slightly improved, whereas perspiration fastness remained unchanged for curcumin dyeing without and with the presence of the mordant. Also, the low‐light resistances of the degummed and grafted silks dyed by curcumin dyestuff were notably improved by the MMA and MAA grafting technique. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100:1169–1175, 2006
Anionic dye adsorption characteristics of surfactant‐modified coir pith, a ‘waste’ lignocellulosic polymer
Authors: Namasivayam C. , Sureshkumar M. V.
Published: January 2006

The surface of coir pith, an agricultural solid waste, was modified using a cationic surfactant hexadecyltrimethylammonium bromide. Adsorption of anionic dyes on surfactant‐modified coir pith was investigated in a series of batch adsorption experiments. Two anionic dyes, acid brilliant blue (acid dye) and procion orange (reactive dye), were used in the adsorption studies. The effect of process variables such as contact time, concentration of the dyes, adsorbent dose, temperature, and pH were studied in order to understand the kinetic and thermodynamic parameters of the process. The kinetics of adsorption obeyed the second‐order rate equation. The equilibrium adsorption data were fitted into the Langmuir and Freundlich isotherms. It was found that modified coir pith yielded adsorption capacities of 159 and 89 mg/g for acid brilliant blue and procion orange, respectively. Mechanisms involving ion exchange and chemisorption might be responsible for the uptake of dyes. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1538–1546, 2006
Chemical modification of nylon 6 and polyester fabrics by ozone‐gas treatment
Authors: Lee Muncheul , Lee Myung Sun , Wakida Tomiji , Tokuyama Takako , Inoue Goichi , Ishida Shinzo , Itazu Toshihiko , Miyaji Yukino
Published: January 2006

In a previous article, we reported on the ozone‐gas treatment of wool and silk fabrics in relation to the gas‐phase processing of textile fabrics. The treatment incorporated an oxygen element into the fiber surface and contributed to an increase in water penetration into the fabric. In this study, nylon 6 and polyester fabrics were treated with ozone gas in the same way as that of the wool and silk fabrics. The treatment incorporated much more oxygen into the fiber surface in the form of COH and COOH, as shown by electron spectroscopy for chemical analysis. Water penetration increased considerably with treatment, and the apparent dyeing rate and equilibrium dye uptake were also improved, especially for the polyester fabric, despite an increase in the crystallinity. Therefore, it seemed that the treatment brought about a change not only in the fiber surface but also in the internal structure of the fibers (the crystalline and amorphous regions) with regard to the dyeing behavior. Further, the mechanical characteristics of the ozone‐gas‐treated polyester and nylon 6 fabrics were measured with a Kawabata evaluation system apparatus. The shearing modulus and hysteresis widths increased with treatment, especially for the polyester fabric. Therefore, it was clear that the treatment caused a change in the fabric hand to crisp. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1344–1348, 2006
Copolymers of styrene with a quaternary europium complex
Authors: Pan Yuanfeng , Zheng Anna , Hu Fuzeng , Xiao Huining
Published: January 2006

A complex of Eu3+, benzoate (BA), acrylate (AA), and 1,10‐phenanthroline (Phen) was synthesized in this work. The structure of Eu(BA)2(AA)(Phen) was characterized with elemental analysis, FTIR, and UV spectroscopy. Copolymers containing rare earth complex were prepared via the copolymerization of Eu3+(BA)2(AA)(Phen) with styrene. Semitransparent, luminescent polymer materials with high fluorescent intensity were obtained. The as‐synthesized materials were further characterized by means of IR and UV spectra, which indicated that they were copolymers instead of blends. The fluorescence spectra of the copolymers revealed the intense UV absorption characteristics of the rare earth complex present in the materials, as long as only a small portion of the complex was incorporated into the copolymers. Moreover, thermal analysis showed that the copolymer had excellent heat stability. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1506–1510, 2006
Grafting of methyl methacrylate onto Antheraea pernyi silk fiber with the assistance of supercritical CO2
Authors: Peng Qi , Xu Qun , Sun Dengfeng , Shao Zhengzhong
Published: January 2006

Graft copolymerization of methyl methacrylate (MMA) onto Antheraea pernyi silk fibers, initiated by benzoyl peroxide in the supercritical CO2 was investigated. The grafting degree was determined as a function of impregnating pressure, impregnating time, monomer concentration, initiator concentration, and reaction time. The structural properties of MMA‐grafted fiber were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. Grafted MMA was chemically bonded and/or physically adhered to the surfaces of the fibers. The grafted silk fibers exhibited two steps of weight loss according to the characteristic of each component as demonstrated by the thermogravimetric analysis. The water‐retention values indicated that the hydrophobic nature of the fibers was improved. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1299–1305, 2006
High modulus polypropylene fibers. II. Influence of fiber preparation upon structure and morphology
Authors: Gregor‐Svetec Diana
Published: January 2006

The influence of drawing on the limiting draw ratio upon formation of the morphological structure of fibers spun from binary polypropylene (PP) blends was studied. Fibers were spun from a fiber‐grade CR‐polymer and from the blends of a fiber‐grade CR‐polymer with a molding‐grade polymer in the composition range of 10–50 wt % added. As‐spun fibers were immediately moderately and additionally highly drawn at the temperature of 145°C. The structure and morphology of these fibers were investigated by small‐angle X‐ray scattering, wide‐angle X‐ray scattering, differential scanning calorimetry, scanning electron microscopy, density, birefringence, and sound velocity measurements. It was shown that continuously moderately drawn fibers are suitable precursors for the production of high tenacity PP fibers of very high modulus, because of so called oriented “smectic” structure present in these fibers. With drawing at elevated temperature, the initial metastable structure of low crystallinity was disrupted and a c‐axis orientation of monoclinic crystalline modification was developed. Hot drawing increased the size of crystallites and crystallinity degree, the orientation of crystalline domains, and average orientation of the macromolecular chains and resulted in extensive fibrillation and void formation. It was found that the blend composition has some influence on the structure of discontinuously highly drawn fibers. With increasing the content of the molding‐grade polymer in the blend, the size of crystalline and amorphous domains, density and crystallinity, as well as amorphous orientation decreased. Relationship has been established between the mechanical properties, crystallinity, and orientation of PP fibers. It was confirmed that by blending the fiber‐grade CR‐polymer by a small percentage of the molding‐grade polymer, maximization of elastic modulus is achieved, mainly because of higher orientation of amorphous domains. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1067–1082, 2006
Controlled heterogeneous modification of cellulose fibers with fatty acids: Effect of reaction conditions on the extent of esterification and fiber properties
Authors: Freire C. S. R. , Silvestre A. J. D. , Neto C. Pascoal , Belgacem M. N. , Gandini A.
Published: January 2006

The controlled heterogeneous partial modification of cellulose fibers with fatty acids, partially preserving the fiber structure, was investigated. The effect of reaction conditions, such as reaction time, fatty acid chain length, and solvent types (swelling and non swelling), on the extent of esterification and fiber properties was evaluated by elemental analysis, IR‐ATR, X‐ray diffraction, 13C CPMAS NMR, contact angle measurement, thermogravimetry, and scanning electron microscopy. The degree of substitution (DS) increased with reaction time and with the swelling effect of the reaction medium and decreased with the fatty acids chain length. Higher the DS, higher is the decrystallization of cellulose as a result of the heterogeneous esterification reaction. The esterification with fatty acids enhanced the hydrophobic character of the fibers, but decreased their thermal stability. These properties are not strongly affected by the DS in the range investigated, viz. up to 1.4. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1093–1102, 2006
Improvement of thermal stability of new heteroaromatic poly(azomethine urethane)s
Authors: Issam A. M. , Ismail J.
Published: January 2006

New poly(azomethine urethane)s were synthesized in the conventional literature manner by reacting a new bisphenol‐containing azomethine group, N,N′‐bis(4‐hydroxyl‐3‐methoxy benzylidine)‐2,6‐diaminopyridine (I) with various diisocyanates, such as hexamethylene diisocyanate (HDI) (a), methylene‐4,4′‐diphenyl diisocyanate (MDI) (b), and toluene‐2,4‐diisocyanate (TDI) (c). The resulting polymers I(a–c) were confirmed by 1H‐NMR, FTIR, UV, and CHN analyses. Thermogravimetric analysis (TGA) revealed that the polymers have high thermal stability. A semicrystalline behavior was noticed for polymers by wide‐angle X‐ray diffraction (WAXD) and differential scanning calorimetry (DSC). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1198–1204, 2006
Miscibility enhancement on the immiscible poly (vinyl pyrrolidone) and poly (ethyl methacrylate) with poly (vinyl phenol)
Authors: Hsu Wen‐Ping
Published: January 2006

The miscibility behavior of ternary blends of poly (vinyl phenol) (PVPh)/poly (vinyl pyrrolidone) (PVP)/poly (ethyl methacrylate) (PEMA) was investigated mainly with calorimetry. PVPh is miscible with both PVP and PEMA on the basis of the single Tg observed over the entire composition range. FTIR was used to study the hydrogen bonding interaction between the hydroxyl group of PVPh and the carbonyl group of PVP and PEMA at various compositions. Furthermore, the addition of PVPh is able to enhance the miscibility of the immiscible PVP/PEMA and eventually transforms it into a miscible blend, especially when the ratio between PVP/PEMA is 3:1, probably because of favorable physical interaction. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1205–1213, 2006
The effect of substitution levels on the luminescent and degradation properties of fluorescent poly(ester‐anhydride)s
Authors: Fan Jun , Jiang H. L. , Chen Dian , Zhu K. J.
Published: January 2006

In this work, two kinds of diacid monomers were synthesized by a convenient scheme, where 4‐hydroxy‐3‐methoxybenzoic acid (vanillic acid) or 4‐hydroxy‐3,5‐dimethoxybenzoic acid (syringic acid) directly condensated with succinic chloride. Corresponding polyanhydrides were obtained by melt polycondensation. Copolyanhydrides composed of the new monomers and sebacic acid (SA) were further prepared and characterized by NMR, DSC, and fluorometer. The two new kinds of polyanhydride emit strong fluorescence and have similar fluorescent spectra to poly(di(p‐carboxyphenyl) succinate anhydride) (P(dCPS)). The emission wavelength (λem) of the copolymers could be tuned by the excitation wavelength (λex). Degradation rate of the copolyanhydrides decreased as dMOCPS or ddMOCPS fraction increased, and the degradation duration could be modulated from several days to more than 3 months. It addition, the copolyanhydrides displayed typical surface‐degradation characteristics. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1214–1221, 2006
Synthesis and characteristics of poly(methyl methacrylate)/expanded graphite nanocomposites
Authors: Wang Wen‐ping , Liu Yan , Li Xiao‐xuan , You Ye‐zi
Published: January 2006

In this work, we synthesized poly(methyl methacrylate) (PMMA)/expanded graphite (EG) nanocomposites by a new polymerization method. The volume electrical conductivity of the nanocomposite prepared by this way is very high (when the content of EG is about 8 wt %, the conductivity could reach 60 S/cm). The structure of the nanocomposite was investigated by SEM, TEM, IR, and XRD. And we found temperature and voltage were important parameters of governing the electrical conductivity of PMMA/EG nanocomposites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1427–1431, 2006
The use of 1H NMR and UV–vis measurements for quantitative determination of trans/cis isomerization of a photo‐responsive monomer and its copolymer
Authors: Moniruzzaman M. , Talbot J. D. R. , Sabey C. J. , Fernando G. F.
Published: January 2006

Photo‐induced trans–cis isomerization of trans‐4‐methacryloyloxyazobenzene and its copolymer with methylmethacrylate, synthesized in this work, were investigated in a polar protic (CDCl3) and a polar aprotic (DMSO‐d6) solvent, using 1H‐NMR. The results were cross‐correlated with trans–cis isomerization calculated from UV–visible spectra. The kinetics of the photoisomerization reaction of the monomer species under UV light irradiation is described by a simple first order exchange between the trans and cis forms of the monomer. The behavior was found to be similar for both solvents. The cis‐to‐trans reversion in the absence of irradiation is about 3% of the back reaction under irradiation. For the polymer in solution, the behavior was more complicated and is described by the sum of two equilibria, each of first order exchange kinetics of the trans form with two different types of cis isomer in the polymer; a first type of isomerization similar in behavior to that of the monomer and the second type much faster in cis/trans exchange rate. This bikinetic behavior is in agreement with that of the azobenzene moiety in PMMA as a solid phase mixture. The relative proportion of the two rates comprising the bikinetic effect is solvent‐dependent. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1103–1112, 2006
Preparation and solubility of water–methanol mixtures in sulfonated poly(etherketone) containing a cardo‐ring structure
Authors: Akiba Curato , Watanabe Kenji , Nagai Kazukiyo , Hirata Yuichi , Nguyen Quang Trong
Published: January 2006

The preparation and solubility of water–methanol mixtures in sulfonated (1,3‐dihydro‐3‐oxoisobenzofuran‐1,1‐diyl‐1,4‐phenyleneoxy‐1,4‐phenylenecarbonyl‐1,4‐phenyleneoxy‐1,4‐phenylene) (C‐PEK) was systematically studied. The sulfonation was carried out by reacting C‐PEK with 98% sulfuric acid at 60°C. This reaction obeys a first‐order reaction mechanism up to 4 h. The sulfonic acid group was uniformly dispersed in a sulfonated C‐PEK (SC‐PEK) membrane. The introduction of sulfonic acid groups in C‐PEK could increase polymer segmental gaps because of the size of a bulky sulfonic acid group or decrease polymer segmental gaps as a result of polar interactions. The former effect is dominant for SC‐PEK with low sulfonic acid content, whereas the latter occurs for SC‐PEK with high sulfonic acid content. The uptake of pure water or an aqueous methanol solution (e.g., 3, 5, and 10 wt % methanol concentration) in the sulfonated C‐PEK membranes increases with increasing sulfonic acid group content. However, the sulfonated C‐PEK with high sulfonic acid content selectively sorbs water rather than methanol in the membrane. This suggests that the sulfonated C‐PEK membrane could prevent crossover of methanol through the membrane and has potential as a polymer electrolyte for the direct methanol fuel cell. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1113–1123, 2006
Femtosecond‐laser‐assisted wet chemical etching of polymer materials
Authors: Wochnowski C. , Hanada Y. , Cheng Y. , Metev S. , Vollertsen F. , Sugioka K. , Midorikawa K.
Published: January 2006

Polymers are modified by femtosecond‐(fs)‐IR‐laser irradiation under various process parameters. Several sorts of thermoplastic polymer are employed: polymethylmethacrylate (PMMA), fluorinated PMMA, poly‐N‐methyl methacrylimide (PMMI), polystyrol, polycarbonate, polyimide, and polyethylene. After the fs‐laser‐induced modification process, the irradiated area is developed by an aqueous solution of a solvent agent (n‐hexane, benzene, and methylisobutylketone). The surface topography of the fs‐laser‐irradiated area is characterized by stylus‐profilometry before and after the development procedure. Some preliminary explanations are given about the solution mechanism of the fs‐laser‐irradiated polymer region. The experimental results are relevant for the fabrication of three‐dimensional (3D)‐structures in the volume of a transparent polymer material by fs‐laser irradiation. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1229–1238, 2006
Preparation of poly(lactic acid) fiber by dry‐jet‐wet‐spinning. I. Influence of draw ratio on fiber properties
Authors: Gupta Bhuvanesh , Revagade Nilesh , Anjum Nishat , Atthoff Björn , Hilborn Jöns
Published: January 2006

Poly(lactic acid) fiber was prepared by dry‐jet‐wet spinning of the polymer from chloroform solution and with methanol as the precipitating medium. The as‐spun fiber was subsequently made into high strength fiber by two‐step process of drawing at a temperature of 90°C and subsequent heat setting in the temperature range of 120°C. The draw ratio had significant influence on the crystallinity and the tensile strength of the fiber. The fiber with the tenacity of 0.6 GPa and modulus of 8.2 GPa was achieved at a draw ratio of 8. The differential scanning calorimetry revealed an increase in the glass‐transition temperature with the increase in the draw ratio, which suggests the orientation of chains during the drawing process. The surface morphology of the filament as revealed by scanning electron microscopy shows that fibers are porous in nature, but a significant reduction in the porosity and pore size of the fiber was observed with the increase in the draw ratio. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1239–1246, 2006
Hydroxyalkylation of parabanic acid. III. Polymers from parabanic acid and ethylene carbonate
Authors: Zarzyka‐Niemiec Iwona , Naróg Dorota , Lubczak Jacek
Published: January 2006

The influence of initial molar ratio of reagents, amount of catalyst, and temperature of reaction between parabanic acid and ethylene carbonate on structure of product was studied. The reaction led to the opening of the trioxoimidazolidine ring, resulting in formation of thermally resistant linear polymeric products constructed of urea and oxoamidoester subunits linked via imide bond. The percentage of side products was estimated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1443–1449, 2006
Synthesis and magnetic properties of novel complexes of poly(N‐2‐thiazolylmethacrylamide) with Nd(III), Pr(III), and Sm(III)
Authors: Zheng Ping , Sun Weilin , Shen Zhiquan
Published: January 2006

N‐2‐Thiazolylmethacrylamide (NTMA) was polymerized by a radical route to obtain the polymer in good yields. The complexes of PolyNTMA with three rare earth ions Nd(III), Pr(III), and Sm(III) were prepared for the first time. FTIR and 1H NMR were applied to characterize these materials. The magnetic behavior of PolyNTMA–metal complexes was examined as a function of applied magnetic field at 4 K and as a function of temperature (4–300 K) at an applied magnetic field of 30 kOe. It was found that Pr(III) complex exhibits an antiferromagnetic property, while Nd(III) and Sm(III) complexes exhibit a special magnetic property different from the typical magnet. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1289–1293, 2006
The adsorption of water vapor on super absorbent product at low temperatures and low mass
Authors: Bakass M. , Bellat J. P. , Mokhlisse A. , Bertrand G.
Published: January 2006

The adsorption isotherms of water vapor on super absorbent product have the same form of type III isotherm at ambient temperature with the hysteresis phenomena. For temperatures lower than ambient, the isotherms become deformed because of the chains effect. The polymer is characterized by a multilayer adsorption, which occurs before a full‐course is complete. During adsorption reactions, the polymer undergoes rearrangement polymeric network, which results from a cooperative diffusion of the water molecules and from a chain spacing followed by an expansion of the polymeric network. Three types of water molecules adsorbed on polymer were identified: strongly dependent water, adsorbed water, and the water only trapped between the macromolecular chains. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1450–1456, 2006
Wrinkle resistant properties and antibacterial efficacy of cotton fabrics treated with glyoxal system and with combination of glyoxal and chitosan system
Authors: Kittinaovarat Siriwan , Kantuptim Pariya , Singhaboonponp Thanit
Published: January 2006

This study examined the possibility of using glyoxal and chitosan in one‐step finishing to impart both durable press performance and antibacterial efficacy on cotton fabrics. Glyoxal treatment provided good wrinkle resistant property and fair antibacterial activity on the finished fabrics, but the loss of breaking strength retention of the finished fabrics was a main problem of this treatment. Chitosan added in the combination of glyoxal and chitosan system also provided comparable results in wrinkle resistant and antibacterial properties on the finished fabrics as the glyoxal did. The advantage of chitosan in the combination of glyoxal and chitosan system was the improvement of the breaking strength retention of the finished fabrics without affecting the durable press property of the finished fabrics. However, the yellowing of the finished fabric was still a problem when the finished fabrics were treated with the combination of glyoxal and chitosan system. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1372–1377, 2006
Synthesis of a difunctional organolithium compound as initiator for the polymerization of styrene‐butadiene/isoprene‐styrene triblock copolymer
Authors: Lu Zhanxia , Xu Hongde , Li Yang , Hu Youliang
Published: January 2006

A difunctional organolithium compound was prepared by the addition of butyllithium (BuLi) to 1,4‐bis(4‐methyl‐1‐phenylethenyl)benzene (MPEB). The effects of the solvent, polar modifier (THF), butyl lithium structure, and reaction time on the formation of the difunctional organolithium compound were studied. Results showed that toluene as solvent was in favor of the addition reaction over cycohexane, in the absence of the polar modifier. However, cycohexane was a better option as solvent for the addition reaction, when polar modifier was employed. A small amount of polar modifier could efficiently accelerate the reaction rate and have no significant effect on the structure of the polydiene, which was initiated by the polar modifier containing organolithium compound. Results also showed that isobutyl lithium was more active in the addition reaction than n‐butyl lithium, because of inductive effect. The optimum molar ratio of THF/Li+ was determined as 4. The THF containing difunctional organolithium cyclohexane solution was sequentially used in the step‐wise polymerization of triblock thermoplastic copolymer SIBS. The so‐prepared SIBS shared the similar phase separation structure with SBS and exhibited excellent mechanic properties. As the content of the central polyisoprene block increases, the tensile strength of the copolymer is decreased, and the elongation at break is increased. The glass transition temperature Tg of the central block was correlated with its content as Tg = 0.33 × −62.81, where × is the wt % of the central block, based on the triblock copolymer. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1395–1402, 2006
Separation characteristics of acetic acid–water mixtures using poly(vinyl alcohol‐g‐4‐vinyl pyridine) membranes by pervaporation and temperature difference evapomeation techniques
Authors: Asman Gülsen , Şanlı Oya
Published: January 2006

The separation of acetic acid–water mixtures was carried out using pervaporation (PV) and temperature difference evapomeation (TDEV) methods. For the separation process, 4‐vinyl pyridine was grafted on poly(vinyl alcohol). Membranes were prepared from the graft‐copolymer by casting method and crosslinked by heat treatment. The effects of feed composition on the separation characteristics were studied and the performances of the separation methods were compared. Permeation rates were found to be high in PV whereas separation factors were high in TDEV method. Membranes gave permeation rates of 0.1–3.0 kg/m2h and separation factors of 2.0–61.0 depending on the composition of the feed mixture and the method. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1385–1394, 2006
The reaction in water of UF resins with isocyanates at short curing times: A 13C NMR investigation
Authors: Wieland S. , Pizzi A. , Hill S. , Grigsby W. , Pichelin F.
Published: January 2006

CP MAS 13C NMR spectra of hardened resins have shown that urethane bridges derived from the reaction of the isocyanate group with the hydroxymethyl group of urea do form even at fast curing times comparable to what was used in the wood panels industry, in lower proportions than what was shown earlier. Polyureas and biurets obtained from the reaction of isocyanate with water are the predominant crosslinking reactions of pMDI alone and in UF/pMDI resin systems under fast curing conditions. Residual, unreacted isocyanate groups in the hardened network are consistently observed. Their proportion markedly decreases when the original proportion of urea–formaldehyde (UF) resin is high and that of pMDI is low. Under these fast curing conditions, the UF resin appears to self‐condense through an unusually high proportion of methylene ether links rather than methylene bridges alone. A marked proportion of residual, unreacted hydroxymethyl groups is also noticeable, initially, in the UF self‐condensation network. Direct NMR tests on thin hardboard bonded under fast pressing conditions with different proportions of UF/pMDI confirmed that crosslinking due to polyureas and biurets formation are predominant in the crosslinking of pMDI when alone and in UF/pMDI resin systems. They confirmed that residual, unreacted isocyanate groups are present in the finished panel. Their proportion is higher when the proportion of pMDI in the system is high. The presence or absence of urethanes could not be confirmed directly on the panels as the relevant peaks are masked by the wood carbohydrates signals of wood cellulose and hemicelluloses. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1624–1632, 2006
Hydroxymethylation and polycondensation reactions in urea–formaldehyde resin synthesis
Authors: Christjanson Peep , Pehk Tõnis , Siimer Kadri
Published: January 2006

Formaldehyde–urea (F/U) reaction products with molar ratios of 1.8, 2.1, and 2.4 were synthesized at pH 8.3, and the last one also at pH 4.5 using 45% formaldehyde aqueous solution. For obtaining the resin, the synthesis of F/U 2.1 was continued by acid‐catalyzed condensation at pH 4.5 and posttreatment with second part of U (F/U 1.05/1) at 70°C and pH 8.3. The products were analyzed using 13C‐NMR spectrometry. Higher excess of F increases the dihydroxymethyl content on account of smaller dimethylene ether content. Certain 13C chemical shifts in carbonyl and methylene region of spectra were assigned to trishydroxymethylurea, being the main trisubstituted urea compound in hydroxymethylated product. Acid catalyst promotes the formation of methylene groups by polycondensation of hydroxymethyl groups, against the background of similar content of dimethylene ethers in both catalytic conditions. The ratio of linear/branched chains is emphasized in characterizing the resin structure. Higher hydroxymethyl content in acid‐catalyzed polycondensation is an advantage of three‐step synthesis technology. The amount of binding methylene and dimethylene ether groups linked only to secondary amino groups can be increased by transhydroxymethylation with subsequent polycondensation in posttreatment with U in suitable reaction conditions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1673–1680, 2006
Reactions of copper ions with amines in the presence of self‐assembled fluorinated oligomeric aggregates
Authors: Sawada Hideo , Furukuwa Rika , Sasazawa Kazuo , Toriba Ken‐Ichi , Ueno Katsuya , Hamazaki Kazuo
Published: January 2006

Copper acetylacetonate reacted with N,N‐diethylmethylamine and 4,4′‐thiobis(6‐t‐butyl‐o‐cresol) in the presence of self‐assembled fluorinated oligmeric aggregates formed by fluoroalkyl end‐capped 2‐[3‐(2H‐benzotriazol‐2‐yl)‐4‐hydroxyphenyl]ethyl methacrylate–N,N‐dimethylacrylamide cooligomer [RF–(BTRI)x–(DMAA)y–RF; RF = CF(CF3)OCF2CF(CF3)OC3F7] to afford stable fluorinated aggregates–copper ions nanocomposites. These fluorinated oligomeric aggregates–copper ions nanocomposites thus obtained were applied to the dispersion of copper ions nanocomposites above the traditional organic polymeric materials such as poly(methyl methacrylate) (PMMA) surface. On the other hand, copper (II) chloride reacted with hydrazine hydrate in the presence of fluorinated oligomeric aggregates formed by fluoroalkyl end‐capped N,N‐dimethylacrylamide homooligomer to afford stable copper nanoparticles. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1328–1334, 2006
Recent human‐induced salinity changes in Ramsar‐listed Orielton Lagoon, south‐east Tasmania, Australia: a new approach for coastal lagoon conservation and management
Authors: Saunders Krystyna M. , Mcminn Andrew , Roberts Donna , Hodgson Dominic A. , Heijnis Henk
Published: January 2006

Many coastal lagoons in eastern Australia have changed as a result of recent human activities. However, it is often difficult to determine the extent of change and the ecological implications. A palaeoecological approach allows a quantitative assessment of how an aquatic ecosystem changes and responds to human impacts beyond what is possible with historical data or monitoring programmes.

Orielton Lagoon (south‐east Tasmania, Australia) is a Ramsar‐listed coastal wetland of international importance for conservation. This study was undertaken at the site to determine whether recent anthropogenic hydrological modifications to the lagoon had influenced its ecology, particularly salinity, and compromised its Ramsar status.

A diatom–salinity transfer function was constructed from a training data set of 96 diatom taxa from 34 sampling sites in 19 lagoons along the east coast of Tasmania.

The salinity of Orielton Lagoon has changed in response to a causeway constructed across its mouth, which has transformed the lagoon from an open marine environment to an enclosed, virtually stagnant, brackish water body.

These changes have compromised the protected coastal wetland status of Orielton Lagoon. Environmental remediation attempts have since partially restored the natural hydrology of the lagoon and it is now returning towards the state it was in prior to causeway construction.

A palaeoecological approach using diatoms was found to be successful in reconstructing recent salinity changes and investigating human impacts on Orielton Lagoon over the last 50–55 years.

Copyright © 2006 John Wiley & Sons, Ltd.
Acquired resistance to chloroquine in human CEM T cells is mediated by multidrug resistance–associated protein 1 and provokes high levels of cross‐resistance to glucocorticoids
Authors: Oerlemans Ruud , van der Heijden Joost , Vink Josefien , Dijkmans Ben A. C. , Kaspers Gertjan J. L. , Lems Willem F. , Scheffer George L. , Ifergan Ilan , Scheper Rik J. , Cloos Jacqueline , Assaraf Yehuda G. , Jansen Gerrit
Published: January 2006

Objective

To explore the onset and molecular mechanism of resistance to the antimalarial disease‐modifying antirheumatic drug (DMARD) chloroquine (CQ) in human CEM T cells.

Methods

Human CEM cells were used as an in vitro model system to study the development of CQ resistance by growing cells in stepwise increasing concentrations of CQ.

Results

Over a period of 6 months, CEM cell lines developed 4–5‐fold resistance to CQ. CQ resistance was associated with the specific overexpression of multidrug resistance–associated protein 1 (MRP‐1), an ATP‐driven drug efflux pump. This was illustrated by 1) overexpression of MRP‐1 by Western blotting and 2) the complete reversal of CQ resistance by the MRP‐1 transport inhibitors MK571 and probenecid. Importantly, CQ‐resistant CEM cells retained full sensitivity to other DMARDs, including methotrexate, leflunomide, cyclosporin A, and sulfasalazine, but exhibited a high level of cross‐resistance (>1,000‐fold) to the glucocorticoid dexamethasone. The mechanistic basis for the latter was associated with aberrant signaling via the cAMP–protein kinase A pathway, since the cAMP‐inducing agent forskolin reversed dexamethasone resistance. Finally, CQ‐resistant CEM cells displayed a markedly reduced capacity to release proinflammatory cytokines (tumor necrosis factor α) and chemokines (interleukin‐8).

Conclusion

Induction of overexpression of the multidrug resistance efflux transporter MRP‐1 can emerge after long‐term exposure to CQ and results in CQ resistance and collateral resistance to dexamethasone. These findings warrant further detailed investigations into the possible role of MRP‐1 and other members of the superfamily of drug efflux pumps in diminishing the efficacy of DMARDs in rheumatoid arthritis treatment.
Interleukin‐1 in combination with oncostatin M up‐regulates multiple genes in chondrocytes: Implications for cartilage destruction and repair
Authors: Barksby H. E. , Hui W. , Wappler I. , Peters H. H. , Milner J. M. , Richards C. D. , Cawston T. E. , Rowan A. D.
Published: January 2006

Objective

To identify the genes up‐regulated by interleukin‐1 (IL‐1) in combination with oncostatin M (OSM) in chondrocytes that may be involved in mechanisms of cartilage repair and degradation.

Methods

Gene microarray and real‐time polymerase chain reaction (PCR) experiments were performed using RNA from SW1353 chondrocytes and primary human articular chondrocytes. Sections prepared from murine joints, injected with adenovirus vectors overexpressing IL‐1 and/or OSM, were analyzed by immunohistochemistry for selected proteins.

Results

The combination of IL‐1 and OSM markedly up‐regulated the expression of various genes, including matrix metalloproteinases (MMPs), cytokines, chemokines, extracellular matrix components, and genes involved in signal transduction. Real‐time PCR confirmed a synergistic induction of several MMPs, activin A, pentraxin 3 (PTX‐3), and IL‐8. The in vivo findings further indicated that stimulation with IL‐1 plus OSM induced protein expression of activin A, PTX‐3, and KC (the murine homolog of IL‐8), as compared with the changes induced by individual cytokine treatment and unstimulated controls.

Conclusion

The results confirm that the potent proinflammatory cytokine combination of IL‐1 plus OSM synergistically and coordinately up‐regulates many genes and several MMPs. Moreover, chondrocytes exhibit a potential repair response following this procatabolic stimulus such that the repair mechanisms are ultimately overwhelmed by degradative processes in the cartilage. This gene‐profiling study provides insight into the complex processes that mediate joint disease in the inflammatory arthritides through the coordinated expression of multiple genes.
Validity, factor structure, and clinical relevance of the AUSCAN osteoarthritis hand index
Authors: Allen Kelli D. , Jordan Joanne M. , Renner Jordan B. , Kraus Virginia B.
Published: January 2006

Objective

The Australian/Canadian (AUSCAN) Osteoarthritis Hand Index is a self‐report assessment of pain, stiffness, and function in patients with hand osteoarthritis (OA). Small studies have confirmed the reliability, construct validity, and responsiveness of this measure, but the factor structure has not been examined. In this study, we examined the clinimetric properties and clinical relevance of the AUSCAN index in a large sample of patients with familial hand OA.

Methods

The study group comprised 700 patients (80% female, mean age 69 years) who were part of a study on the genetics of generalized OA. All patients had radiographic hand OA bilaterally. The analyses examined internal consistency, factor structure, and relationships of the subscales to grip and pinch strength and a single‐item pain measure.

Results

Internal consistency was high for the total AUSCAN index and the subscales (Cronbach's α = 0.93–0.96). The AUSCAN function subscale had the strongest correlation with grip and pinch strength, and the pain subscale had the strongest correlation with the single‐item pain measure, thus supporting the construct validity of these subscales. Factor analysis showed that all pain and function items clearly loaded on the subscale they were intended to measure. Each 1‐unit increase in the AUSCAN function subscale was associated with a clinically relevant decrease in hand strength.

Conclusion

The results of this study strongly confirm the clinimetric properties of the AUSCAN index, including the validity of specific subscales. Results indicate that the AUSCAN index can measure meaningful changes in pain, stiffness, and function.
PYPAF1 nonsense mutation in a patient with an unusual autoinflammatory syndrome: Role of PYPAF1 in inflammation
Authors: Jéru I. , Hayrapetyan H. , Duquesnoy P. , Sarkisian T. , Amselem S.
Published: January 2006

Objective

To gain insight into the pathophysiology of an unusual autoinflammatory syndrome, in a patient of Armenian origin, that mimicked familial Mediterranean fever (FMF) but with episodes triggered by generalized exposure to cold, and to further elucidate the controversial function of the protein encoded by PYPAF1, whose mutations (exclusively missense to date) have been identified in 3 hereditary recurrent fever syndromes.

Methods

The patient's DNA was screened for mutations in both MEFV, the gene responsible for FMF, and PYPAF1. The ability of different recombinant PYPAF1 isoforms, expressed in HEK 293 cells, to regulate NF‐κB signaling was subsequently assessed.

Results

No disease‐causing mutation was found in MEFV. However, a nonsense mutation (p.Arg554X) was identified in PYPAF1; this defect resulted in a truncated protein lacking all leucine‐rich repeats. Study of the wild‐type and mutant PYPAF1 recombinant proteins revealed that PYPAF1 inhibited NF‐κB proinflammatory pathways, and that the identified nonsense mutation impaired this property.

Conclusion

These molecular and clinical findings, together with the clinical manifestations in the patient, which call into question the current nosology of the hereditary recurrent fever syndromes, are consistent with the hypothesis that PYPAF1 acts as an inhibitor of NF‐κB signaling. They also provide a clear elucidation of the functional consequences of this nonsense PYPAF1 mutation not previously described in the literature, which result in a partial loss of function and may thereby explain the pathophysiology of the autoinflammatory syndrome observed in this patient.
PUMA regulation and proapoptotic effects in fibroblast‐like synoviocytes
Authors: Cha Hoon‐Suk , Rosengren Sanna , Boyle David L. , Firestein Gary S.
Published: January 2006

Objective

Although p53 is overexpressed in rheumatoid arthritis (RA) synovial tissue (ST), few synoviocytes undergo apoptosis. This could be partly due to low expression of proapoptotic genes. Deficient p53 up‐regulated modulator of apoptosis (PUMA), which is a major effector of p53‐mediated cell death, could contribute to this phenomenon. To evaluate a method to induce apoptosis, the expression and function of PUMA was investigated in ST and cultured fibroblast‐like synoviocytes (FLS).

Methods

PUMA expression in ST was measured by immunohistochemistry, Western blot analysis, and quantitative polymerase chain reaction analysis. Ad‐p53 and plasmids encoding hemagglutinin‐tagged, full‐length PUMA expression vector (HA‐PUMA), PUMA lacking the Bcl‐2 homology 3 domain, or pCEP4 were used to transfect FLS. Apoptosis was quantified by trypan blue exclusion, DNA fragmentation, and caspase 3 activation.

Results

PUMA protein was detected in RA ST, although most of the immunoreactive protein was localized to sublining cells rather than the intimal lining synoviocytes. Western blot analysis showed no difference between RA ST and osteoarthritis (OA) ST. PUMA messenger RNA was detected in RA and OA ST, although the amounts were markedly lower than in the spleen and FLS. To determine if PUMA was inducible, FLS were transduced with Ad‐p53. Even though p53 protein was produced and p21 expression was increased, PUMA expression was not enhanced. Consistent with this observation, Ad‐p53 did not induce apoptosis in FLS. However, HA‐PUMA transfection into FLS resulted in rapid apoptosis with the activation of caspase 3.

Conclusion

PUMA can induce apoptosis by FLS and represents a potential target in RA.
Cartilage repair using bone morphogenetic protein 4 and muscle‐derived stem cells
Authors: Kuroda Ryosuke , Usas Arvydas , Kubo Seiji , Corsi Karin , Peng Hairong , Rose Tim , Cummins James , Fu Freddie H. , Huard Johnny
Published: January 2006

Objective

Muscle‐derived stem cells (MDSCs) isolated from mouse skeletal muscle exhibit long‐time proliferation, high self‐renewal, and multipotent differentiation. This study was undertaken to investigate the ability of MDSCs that were retrovirally transduced to express bone morphogenetic protein 4 (BMP‐4) to differentiate into chondrocytes in vitro and in vivo and enhance articular cartilage repair.

Methods

Using monolayer and micromass pellet culture systems, we evaluated the in vitro chondrogenic differentiation of LacZ‐ and BMP‐4–transduced MDSCs with or without transforming growth factor β1 (TGFβ1) stimulation. We used a nude rat model of a full‐thickness articular cartilage defect to assess the duration of LacZ transgene expression and evaluate the ability of transplanted cells to acquire a chondrocytic phenotype. We evaluated cartilage repair macroscopically and histologically 4, 8, 12, and 24 weeks after surgery, and performed histologic grading of the repaired tissues.

Results

BMP‐4–expressing MDSCs acquired a chondrocytic phenotype in vitro more effectively than did MDSCs expressing only LacZ; the addition of TGFβ1 did not alter chondrogenic differentiation of the BMP‐4–transduced MDSCs. LacZ expression within the repaired tissue continued for up to 12 weeks. Four weeks after surgery, we detected donor cells that coexpressed β‐galactosidase and type II collagen. Histologic scoring of the defect sites 24 weeks after transplantation revealed significantly better cartilage repair in animals that received BMP‐4–transduced MDSCs than in those that received MDSCs expressing only LacZ.

Conclusion

Local delivery of BMP‐4 by genetically engineered MDSCs enhanced chondrogenesis and significantly improved articular cartilage repair in rats.
Morphologic and quantitative assessment of CD20+ B cell infiltrates in rheumatoid arthritis–associated nonspecific interstitial pneumonia and usual interstitial pneumonia
Authors: Atkins Sarah R. , Turesson Carl , Myers Jeffery L. , Tazelaar Henry D. , Ryu Jay H. , Matteson Eric L. , Bongartz Tim
Published: January 2006

Objective

B lymphocytes are emerging as important elements in the events leading to joint destruction in rheumatoid arthritis (RA). However, B lymphocytes have not been studied in rheumatoid arthritis (RA)–associated lung disease. We performed a morphologic and quantitative analysis of B lymphocytes and plasma cells in RA‐associated interstitial pneumonia (IP) in comparison with idiopathic IP and normal lungs.

Methods

Open‐lung biopsy specimens from patients with RA‐associated IP (n = 18), patients with idiopathic IP (n = 21), and control subjects (n = 11) were stained with antibodies to CD20 and CD138. Morphologic patterns of stained specimens were characterized and staining was quantified using computer‐assisted image analysis.

Results

In RA‐associated IP, marked follicular B cell hyperplasia was detected, which was limited almost entirely to peribronchiolar lymphoid aggregates. Plasma cells were also present in large numbers, but showed a more diffuse tissue infiltration. Quantification of B cells demonstrated higher cellularity in RA‐associated IP (median 2.0%, interquartile range [IQR] 1.0–5.7) as compared with idiopathic IP (0.9%, IQR 0.5–2.1). Control specimens showed a significantly smaller number of B cells compared with both diseases (0.4%, IQR 0.1–1.3). In RA patients who were smokers and in those who were male, the proportion of CD20+ tissue areas further increased to 4.3% (IQR 1.0–5.8) and 3.9% (IQR 0.7–6.9), respectively.

Conclusion

We demonstrated a significant follicular B cell hyperplasia in RA‐associated IP. The differences between RA‐associated IP and idiopathic IP imply a differential emphasis of B cell–mediated mechanisms in the 2 diseases despite radiologic and histologic similarities and provide a rationale for studying functional aspects of B cell involvement in the pathogenesis of RA‐associated IP.
Applying incremental tree induction to retrieval from manuals and medical texts
Authors: White Kieran J. , Sutcliffe Richard F. E.
Published: January 2006

The Decision Tree Forest (DTF) is an architecture for information retrieval that uses a separate decision tree for each document in a collection. Experiments were conducted in which DTFs working with the incremental tree induction (ITI) algorithm of Utgoff, Berkman, and Clouse (1997) were trained and evaluated in the medical and word processing domains using the Cystic Fibrosis and SIFT collections. Performance was compared with that of a conventional inverted index system (IIS) using a BM25‐derived probabilistic matching function. Initial results using DTF were poor compared to those obtained with IIS. We then simulated scenarios in which large quantities of training data were available, by using only those parts of the document collection that were well covered by the data sets. Consequently the retrieval effectiveness of DTF improved substantially. In one particular experiment precision and recall for DTF were 0.65 and 0.67 respectively, values that compared favorably with values of 0.49 and 0.56 for IIS.