bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sodium and Sodium Alloys
Authors: Lemke Charles H. , Markant Vernon H. 
Published: September 2006

AbstractOf all the alkali metals, sodium has had perhaps the greatest commercial success, owing to its relative ease of manufacture and its important role worldwide in the manufacture of organolead compounds for use as gasoline octane enhancers. The decline of organoleads in North America has greatly affected U.S. production. Other sodium uses exist, but none requiring the massive quantities needed for lead antiknock compounds. Most sodium is made electrolytically. Various electrochemical cells are described. Sodium continues to have an important role in the manufacture of many organic chemicals as a reducing agent. Newer uses include sodium batteries, flue‐gas cleanup, and alloy surface modification.
Terpenoids
Authors: Sell Charles S. 
Published: September 2006

AbstractThe terpenoids are a family of natural products defined as being those possessing a carbon skeleton based on isoprene units. This skeletal feature stems from their biosynthesis from mevalonic acid. They serve a wide range of functions in nature including defensive resins, pheromones, antioxidants, and the pigments responsible for vision. It is not surprising therefore that they are also of considerable importance commercially and find application as flavors, fragrances, agrochemicals, and pharmaceuticals. Volatile terpenoids, such as geraniol, linalool, citronellol, citral, and the ionones and damascones, are important in the flavor and fragrance industry. Campholenic aldehyde, the precursor for a range of sandalwood odored materials, is an example of a key terpenoid intermediate. Currently, the best‐known terpenoid pharmaceutical is probably the anticancer drug paclitaxel.Industrial routes to terpenoid compounds comprise an interesting mixture of extraction from nature, partial synthesis from natural feedstocks and total synthesis from petrochemicals. In many instances, two or even all three of these possibilities exist in technocommercial equilibrium. Principal feedstocks include α‐pinene, β‐pinene, myrcene, limonene, isoprene, isobutylene, acetone, and acetylene.In this article, a brief summary of the biosynthesis of terpenoids is followed by a description of the main industrial routes to those of commercial importance. The remainder comprises a series of monographs on the commercially more important members of the family including monoterpenes, oxygenated monoterpenoids, sesquiterpenoids, diterpenoids, triterpenoids, carotenoids, and terpenoid degradation products, such as the ionones, damascones, and ambergris chemicals.
Follow‐up of the course of the anionic ring‐opening polymerization of lactams onto an isocyanate‐bearing polymer backbone in the melt
Authors: Hu Guo‐Hua , Li Huxi , Feng Lian‐Fang 
Published: September 2006

AbstractIn this study, a batch mixer was used as a rheoreactor to carry out and follow up in real time the rate of the anionic polymerization of ε‐caprolactam onto a 3‐isopropenyl‐α,α‐dimethylbenzene isocyanate bearing polypropylene (PP‐g‐TMI) in the presence of sodium ε‐caprolactam as a catalyst. The isocyanate group in the PP‐g‐TMI was capable of activating the anionic polymerization, leading to the formation of a graft copolymer with polypropylene as the backbone and polyamide 6 as the grafts. The polymerization rate was related to the viscosity increase of the polymerization system. The latter then resulted in a concomitant torque increase. It was shown that torque was a rapid, convenient, and approximate measure of the polymerization rate. The use of the torque allowed for rapid and approximate evaluation of the effects of chemical and operating conditions on the polymerization rate without the need to determine the monomer conversions. Torque profiles were also a very useful piece of information for the design of a reactive extrusion process for the same type of polymerization system. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4394–4403, 2006
Evolution of tension during the thermal stabilization of polyacrylonitrile fibers under different parameters
Authors: Yu Meijie , Wang Chengguo , Bai Yujun , Wang Yanxiang , Zhu Bo 
Published: September 2006

AbstractComplicated physical and chemical reactions can occur during the thermal stabilization of polyacrylonitrile (PAN) fibers, and they can be macroscopically reflected by the evolution of tension in the fibers. In this work, PAN fibers were oxidized under different parameters in a continuous production line. The tension in the fibers was examined in detail and found to be influenced greatly by the stretching ratio, temperature, and time, as well as the porosity of the PAN precursors. As the thermal stabilization proceeded, tension with different characteristics could result from various reaction mechanisms. At the initial stage, a higher temperature was helpful for lowering the tension, but the tension increased with an increasing stretching ratio. In a later stage, the tension was dominantly dependent on the cyclization reaction and increased with increasing temperature or time. Under the same stabilization conditions, the tension in low‐porosity fibers was higher than that in high‐porosity fibers. The microstructures, characterized by high‐resolution transmission electron microscopy, provided some direct evidence for the partially stabilized fibers that the stabilization in the crystalline phase was slower than that in the amorphous phase. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5500–5506, 2006
Pyrrole chemical polymerization on textiles: Kinetics and operating conditions
Authors: Ferrero Franco , Napoli Liuba , Tonin Claudio , Varesano Alessio 
Published: September 2006

AbstractThe chemical polymerization of pyrrole was studied with the aim of defining the best operating conditions for obtaining conductive fabrics of synthetic fibers. Ammonium persulfate was chosen as the oxidant, and various dopants were tested. Among these, naphtalene‐2,6‐disulfonic acid disodium salt enabled the lowest surface resistivity to be reached. Hence, several kinetic runs were performed to explain the influence of some operating conditions as oxidant concentration and temperature. A pseudo‐first‐order kinetic equation was derived, and the reaction rates were found to be practically unaffected by the presence of the textile substrate. Pyrrole polymerization was faster than adsorption of the monomer, suggesting the hypothesis of fast polymerization outside the fibers followed by adsorption onto the fiber surface. The surface coating of polypyrrole was evidenced by microscopic observation of the fiber cross sections. ©2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4121–4126, 2006
Preparation of titanium dioxide/polyacrylate nanocomposites by sol–gel process in reverse micelles and in situ photopolymerization
Authors: Wan Tao , Wang Yue‐Chuan , Feng Fei 
Published: September 2006

AbstractUV‐curable, transparent acrylic resin/titania organic–inorganic hybrid films were prepared by controlled hydrolysis of titanium tetrabutoxide in Span‐85/Tween 80 reverse micelles and the subsequent in situ photopolymerization of the acrylic monomers. UV–vis spectra and atomic force microscopy (AFM) indicated the presence of a nanoscale hybrid composition. The onset of absorption (λonset) of titania in the hybrids appeared between 363.4 and 383.5 nm, which exhibited blue shifts relative to that of bulk anatase (λonset = 385 nm). The titania content increased rapidly at higher temperature and higher TTB content, whereas it increased slowly with longer post‐thermal treatment times. The refractive index and UV shielding properties of the organic polymer were obviously improved with increasing titania content. AFM images showed the inorganic domains (mean size 25.3–28.8 nm) were uniformly dispersed in the polymeric networks. The roughness parameters of the hybrid material were: toughness, 1.5–2.3 nm; root mean square roughness, 4.5–4.6 nm; and peak and valley distance, 9.7–19.4 nm. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5105–5112, 2006
Percolation threshold of electrically conductive master batch for polyester fibers application
Authors: Jin Xin , Xiao Changfa , An Shulin , Jia Guangxia 
Published: September 2006

AbstractIn the case of the electrically conductive master batch (ECMB) for fibers application, higher filler content required to produce adequate conductivity can be accompanied by a reduction in spinnability and mechanical property of final fibers. To minimize these problems, ECMB with the character of lower percolation threshold was designed in this article. Carbon black (CB) was treated by titanate coupling agent. Polymer blend poly(ethylene terephthalate) (PET)/polyethylene(PE) was used as matrix instead of individual polymer matrix. The effects of titanate coupling agent treatment and the composition of polymer blend on the properties of ECMB have been discussed. FTIR and laser particle size distribution analyzer were employed to study the CB. Solubility tests and positive temperature effect peak were used to verify the distribution of CB in the polymer blend. These results showed that CB treated with 2 wt % titanate coupling agent and PET/PE polymer blend with the weight ratio of 60/40 appear to be an effective way to design the ECMB with a low percolation threshold. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4144–4148, 2006
Thermal degradation kinetics of rigid polyurethane foams blown with water
Authors: Li Xiao‐Bin , Cao Hong‐Bin , Zhang Yi 
Published: September 2006

AbstractThe thermal decomposition behavior of rigid polyurethane foams blown with water was studied by dynamic thermogravimetric analysis (TGA) in both nitrogen and air atmosphere at several heating rates ranging from room temperature to 800°C. The kinetic parameters, such as activation energy (E), degradation order (n), and pre‐exponential factor (A) were calculated by three single heating rate techniques of Friedman, Chang, and Coats–Redfern, respectively. Compared with the decomposition process in nitrogen, the decomposition of foams in air exhibits two distinct weight loss stages. The decomposition in nitrogen has the same mechanism as the first stage weight loss in air, but the second decomposition stage in air appears to be dominated by the thermo‐oxidative degradation. The heating rates have insignificant effect on the kinetic parameters except that the kinetic parameters at 5°C/min have higher values in nitrogen and lower values in air, indicating different degradation kinetics in nitrogen and air. The kinetic parameters of foam samples blown with different water level in formulation decline firstly and then increase when water level increases from 3.0 to 7.0 pph. According to the prediction for lifetime and half‐life time of foams, water‐blown rigid foams have excellent thermostability, when used as insulation materials below 100°C. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:4149–4156, 2006
Flame retardant synergism of GUP and boric acid by cone calorimetry
Authors: Gao Ming , Yang Shousheng , Yang Rongjie 
Published: September 2006

AbstractWood was treated with a new composite flame retardant (FRW), with its components guanyl urea phosphate (GUP) and boric acid (BA) to impart flame retardance. The flame retarding behavior of these samples was valued by cone calorimeter. The flammability parameters, including rate of heat release (RHR), total heat release (THR), effective heat of combustion (EHC), total mass loss (TML) and mass loss rate (MLR), yield of CO, smoke production rate (SPR), and specific extinction area (SEA) were recorded simultaneously. By analyzing these data, it was concluded that most combustion parameters of wood decreased by the treatment, especially for the FRW treatment, considerably decreased while the date for wood treated with GUP or boric acid decreased much less for the similar upload, which indicated a synergistic effect of flame retardance and suppressing smoke between GUP and boric acid in FRW, which has not been reported in other researches until now. Meanwhile, the probable flame retardation mechanism was proposed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5522–5527, 2006
Chemiluminescence of isotactic polypropylene induced by photo‐oxidative degradation and natural weathering
Authors: Jipa Silviu , Setnescu Radu , Zaharescu Traian , Setnescu Tanta , Kaci Mustapha , Touati Naima 
Published: September 2006

AbstractThe analysis of the chemiluminescence (CL) kinetic parameters (induction time, oxidation rate, and activation energy) after the UV irradiation and outdoor exposure of isotactic polypropylene (i‐PP) films have been studied. The initial CL emission intensity increased with increasing photodegradation time of i‐PP films. On photodegradation, the activation energies were found to decrease linearly with time of UV‐irradiation and outdoor exposure. The slopes of these linear dependences were used to indicate the degree of photodegradation of the polymer and also for the characterization of the stabilizing effect of the additive. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4623–4629, 2006
Removal of copper ions from water of boilers by a modified natural based, corncobs
Authors: Billon L. , Meric V. , Castetbon A. , Francois J. , Desbrieres J. 
Published: September 2006

AbstractThe objective of this study is to demonstrate the feasibility of using esterified derivatives of corncobs to clean back condensates from high‐pressure industrial boilers. Copper ions were retained by these modified natural polymers based within working pH and temperature conditions even at very low concentrations as 10−12 mol/L. Acrylamide polymers or derivatives were not successful for such applications. The influence of granulometry of crude corncobs and temperature on copper retention was first studied using UV spectroscopic and voltametry techniques. Then esterified derivatives were considered and succinic anhydride derivatives of corncobs are demonstrated to be more efficient than the maleic anhydride derivatives. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4637–4645, 2006
Recycling of NR based cured latex material reclaimed with 2,2′‐dibenzamidodiphenyldisulphide in a truck tire tread compound
Authors: Rajan V. V. , Dierkes W. K. , Joseph R. , Noordermeer J. W. M. 
Published: September 2006

AbstractIt is observed that reclamation of natural rubber latex based rubber using 2,2′‐dibenzamidodiphenyldisulphide as reclaiming agent is an optional methodology for recycling of waste latex rubber (WLR). For progressive replacement of virgin natural rubber by the reclaim, two alternatives curing system were investigated: adjustment or reduction of the curing system with increasing reclaim content, to compensate for the extra amount of curatives brought along by the reclaim. For fixed curing system, as if the reclaim were equivalent to virgin NR. The cure behavior, final crosslink density and distribution, mechanical properties, and dynamic viscoelastic properties of the blends with reclaimed WLR are measured and compared with the virgin compound. The morphology of the blends, sulfur migration, and final distribution are analyzed. The mechanical and dynamic viscoelastic properties deteriorate for both curing systems, but to a lesser extent for fixed curing system compared to adjusted curing system. With the fixed cure system, many properties like tensile strength and compression set do still deteriorate, but tan δ and M300/M100, representative for the rolling resistance of tires are improved. On the other hand, with the adjusted cure system both mechanical and dynamic properties still deteriorate. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:4194–4206, 2006
Synthesis and characterization of butan‐1‐ol modified toluene diisocyanate trimer
Authors: Jin C. , Lu J. , Li W. S. , Zhou L. , Huang Q. M. , Yang X. H. 
Published: September 2006

AbstractButan‐1‐ol modified toluene diisocyanate tri mer (TDI‐trimer) was synthesized and characterized with Fourier transform infrared spectroscopy, gel permeation chromatography, and thermal gravimetry analysis techniques. The modified TDI‐trimer showed good dissolvable ability with hydroxy resin and can be used to produce paints with acrylic polyol resin. The thermal stability of the modified TDI‐trimer was improved by simply increasing both the amount of catalyst and the ratio of NCO/OH, less depended on the kind of catalyst. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4958–4962, 2006
Spectroscopic and electrical properties of polyaniline/CeO2 composites and their application as humidity sensor
Authors: Parvatikar Narsimha , Jain Shilpa , Bhoraskar S. V. , Ambika Prasad M. V. N. 
Published: September 2006

AbstractPolyaniline/CeO2 composites were synthesized by in situ chemical polymerization method using ammonium persulphate as an oxidizing agent. This is the single step polymerization process for the direct synthesis of emeraldine salt phase of polymer. The polymers were characterized by using FTIR spectral analysis, SEM, and XRD studies. Formation of conducting emeraldine salt phase is confirmed by spectroscopic techniques. High temperature conductivity measurements show “thermal activated behavior.” The change in resistance with respect to percentage relative humidity (% RH) is observed, when the pressed pellets of the polymer were exposed to the broad range of humidity (humidity ranging between 10 and 95% RH). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:5533–5537, 2006
Synthesis of poly(acrylic acid)/sodium humate superabsorbent composite for agricultural use
Authors: Mo Chu , Shu‐quan Zhu , Hua‐Min Li , Zhan‐bin Huang , Shu‐qin Li 
Published: September 2006

AbstractA novel poly (acrylic acid)/sodium humate superabsorbent composite was synthesized by graft copolymerization reaction of acrylic acid (AA) on sodium humate micropowder using N,N′‐methylenebisacrylamide (MBA) as a crosslinker and potassium peroxydisulfate (KPS) as an initiator in aqueous solution. The effects on water absorbency of factors such as reaction temperature, initial monomer concentration, and degree of neutralization of AA, amount of crosslinker, initiator, and sodium humate were investigated. The superabsorbent composite was characterized by scanning electron microscopy, and the graft copolymerization reaction of AA on sodium humate micropowder was characterized by IR spectroscopy. Results obtained from this study show that the water absorbency of the superabsorbent composite synthesized under optimal conditions for synthesis with a sodium humate content of 5.3% exhibited absorption of 684 g H2O/g sample in distilled water. Water‐retention in soil is enhanced by the use of the superabsorbent composite. The effect of superabsorbent composite on the growth of corn is reported. The superabsorbent composite may be of use as water management materials for agriculture purposes in desert and drought‐prone areas. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5137–5143, 2006
Rheological study of the curing kinetics of epoxy–phenol novolac resin
Authors: Auad Maria L. , Nutt Steven R. , Stefani Pablo M. , Aranguren Mirta I. 
Published: September 2006

AbstractThe curing reaction of an epoxy–phenolic resin under different conditions was monitored using rheological measurements. The evolution of viscoelastic properties, such as storage modulus, G′, and loss modulus, G″, was recorded. Several experiments were performed to confidently compare the rheological data obtained under varied curing conditions of temperature, catalyst concentration, and reactive ratios. The values of G′ measured at the end of the reactions (at maximum conversion) were independent of the frequency and temperature of the tests in the range of high temperatures investigated. The overall curing process was described by a second‐order phenomenological rheokinetic equation based on the model of Kamal. The effects of the epoxy‐to‐phenolic ratio as well as the curing temperature and the catalyst concentration were also investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4430–4439, 2006
Effect of applied stress on the alkaline hydrolysis of poly(ethylene terephthalate) at 40°C: Relevance to medical textiles
Authors: Rahman Mashiur , East G. C. 
Published: September 2006

AbstractLaboratory‐accelerated degradation tests have been conducted to understand the stability of high tenacity poly(ethylene terephthalate) (PET) as a result of exposure to stressful chemical environments when used as an implantable prosthesis. The experiments were conducted at 40°C to mimic normal physiological conditions. At various time intervals, samples were collected and evaluated for weight loss (%), mechanical properties, and changes in the surface structure. The mechanical properties that were specifically observed include: breaking load, tenacity, breaking strain, work of rupture, and modulus. For all PET fibers loss of work of rupture was the highest. An empirical formula was developed to estimate degradation behavior over time, though such a prediction cannot be verified without further research and observation. The transverse cracks formed on the stressed samples beyond the critical load in an alkaline environment at 40°C are similar to those found on the PET prosthetic grafts. The cracks in the experimental samples at 40°C and those recovered from human bodies both appear more ‘corallite in structures’ versus those at room temperature. Therefore, it is concluded that the arterial stress that the PET prosthetic graft encountered inside the human body was higher than the yield load of the fiber. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4814–4822, 2006
Preparation and characterization of alginate and hydroxyapatite‐based biocomposite
Authors: Parhi Purnendu , Ramanan A. , Ray Alok R. 
Published: September 2006

AbstractIn this article, we report a novel route for the preparation of alginate‐hydroxyapatite biocomposite. Hydroxyapatite has been nucleated on alginate chains by precipitation method to obtain a biomimetic artificial bone‐like composite. The composite was characterized by powder XRD, FTIR, TGA, DTA, and SEM to ascertain its phase homogeneity and particle size distribution. Hydroxyapatite particles on alginate matrix are around 500–1000 nm in diameter. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5162–5165, 2006
Morphology and mechanical properties of high‐impact polystyrene/elastomer/magnesium hydroxide composites
Authors: Chang Suqin , Xie Tingxiu , Yang Guisheng 
Published: September 2006

AbstractTernary composites of high‐impact polystyrene (HIPS), elastomer, and magnesium hydroxide filler encapsulated by polystyrene were prepared to study the relationships between their structure and mechanical properties. Two kinds of morphology were formed. Separation of elastomer and filler was found when a nonpolar poly[styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene] triblock copolymer (SEBS) was incorporated. Encapsulation of filler by elastomer was achieved by using the corresponding maleinated SEBS (SEBS‐g‐MA). The mechanical properties of ternary composites were strongly dependent on microstructure. In this study, the composites with separate dispersion structure showed higher elongation, modulus and impact strength than those of encapsulation structure. Impact‐fracture surface observation showed that the toughening mechanism was mainly due to the massive cavitation and extensive matrix yielding. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:5184–5190, 2006