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Aims This study aimed to investigate differences in baseline and treatment characteristics, and in‐hospital mortality according to the aetiologies of cardiogenic shock in patients undergoing veno‐arterial‐extracorporeal membrane oxygenation (VA‐ECMO). Methods and results The RESCUE registry is a multicentre, observational cohort that includes 1247 patients with cardiogenic shock from 12 centres. A total of 496 patients requiring VA‐ECMO were finally selected, and the study population was stratified by cardiogenic shock aetiology [ischaemic cardiomyopathy (ICM, n = 342) and non‐ICM (NICM, n = 154)]. The primary outcome of interest was in‐hospital mortality. Sensitivity analyses including propensity‐score matching adjustments were performed. Mean age of the entire population was 61.8 ± 14.2, and 30.8% were women. There were significant differences in baseline characteristics; notable differences included the older age of patients with ICM (65.1 ± 13.7 vs. 58.2 ± 13.8, P

Current technological advances in the organic light-emitting diode panel design of foldable smartphones demand advanced adhesives with UV-blocking abilities, beyond their conventional roles of bonding objects and relieving deformation stress. However, optically clear adhesives (OCAs) with UV-blocking ability cannot be prepared using conventional UV-curing methods relying on a photoinitiator. Herein, a new acrylic resin that can be efficiently cured using visible light without oxygen removal is presented, which may be used to develop UV-blocking OCAs for use in current flexible displays. A novel photocatalyst and a specific combination of additives facilitate sufficiently rapid curing under visible light in the presence of UV-absorbers. Only a very small amount of the highly active photocatalyst is required to prepare UV-blocking OCA films with very high transparency in the visible region. Using this system, a UV-blocking OCA that nearly meets the specifications of an OCA used in commercialized foldable smartphones is realized. This technology can also be utilized in other applications that require highly efficient visible light curing, such as optically clear resins, dental resins, and 3D/4D-printable materials.

Carbon has been a raw material for several thousands of industrial products and their production from various bioresources is an active area of research. This article details production of carbon microspheres from rubber wood via hydrothermal carbonization (termed as hydrothermal rubber wood carbon, HTRW carbon). Synthesis were coordinated in two sets: (i) in the first set, excess of water (20-40 × weight of biomass) was used in the hydrothermal process at 180-260 ⁰C for 3-9 hours and (ii) in the second set, water ratio was 25 – 35 × weight of biomass and the HTC reaction temperature fixed at 260 ⁰C. The chemical and physical characteristics of the products were studied by elemental analyzer, X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, gas adsorption studies, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The H/C and O/C atomic ratios of starting rubber wood was 1.78 and 0.85, respectively, which upon processing through the first strategy resulted in H/C ~0.78 and O/C ~0.29; thereby suggesting increased condensation under HTC.

Resistant starch (RS) has been studied for its ability to serve as a substrate for the microbiota present in the human large intestine and for its beneficial physiological effects. The aim of this study was to screen and select novel strains of lactic acid bacteria (LAB) in the genus Bifidobacterium isolated from human fecal samples for further application as probiotics relying on their utilization of RS3, a prebiotic.; Results: LAB were isolated from human fecal samples, based on their ability to utilize RS3 as a carbon source. Consequently, two LAB were identified as Bifidobacterium adolescentis based on morphological, physiological and biochemical properties, and molecular biological analysis. The RS3-utilizing ability of these isolates was shown by the rapid decrease in pH of RS3-MRS media and by the pinhole traces on the surface of RS3 particles. Isolated B. adolescentis JSC2 was shown to be negative for β-glucuronidase, suggesting that it would be safe for human use, and was found to be tolerant towards the acidic, bile-salt environment.; Conclusion: This synbiotics approach of B. adolescentis JCS2, an RS-utilizing probiotics, coupled with RS utilization, is expected to enhance RS utilization in the food industry and be beneficial for the promotion of human health. © 2018 Society of Chemical Industry.; © 2018 Society of Chemical Industry.

Microalgae are gaining importance as a source of high‐value bioproducts. However, data regarding optimization of algal productivity via variation of environmental factors are lacking. Here, we evaluated a novel lighting method for the enhancement of biomass and total fatty acid (TFA) productivities during algal cultivation. We cultivated six different algal strains (Chlorella vulgaris KCTC AG10002, Acutodesmus obliquus KGE18, Uronema sp. KGE03, Micractinium reisseri KGE19, Fragilaria sp., and Spirogyra sp.) under various lighting conditions—continuous light (CL), light‐dark cycle (LD), and continuous dark (CD)—with or without additional flashing light. We monitored dry cell weight (DCW) and TFA concentrations during cultivation. For each algal strain, the growth rate showed markedly different responses to the various lighting modes. The growth rates of C. vulgaris KCTC AG10002 (1.34‐fold DCW increase, LD with flash), A. obliquus KGE18 (5.16‐fold DCW increase, LD with flash), Uronema sp. KGE03 (2.77‐fold DCW increase, CL with flash), and M. reisseri KGE19 (1.52‐fold DCW increase, CL with flash) markedly increased in response to flashing light. Additionally, in some algal strains cultivated under the LD mode, the flashing light treatment induced increased TFA concentrations (C. vulgaris, 1.19‐fold increase; A. obliquus, 2.59‐fold increase; and M. reisseri, 3.31‐fold increase). Phytohormone analysis of M. reisseri revealed increases in growth rate and TFA concentrations, associated with phytohormone induction via flashing light (e.g. 2.93‐fold increase in gibberellic acid); hence, flashing light can promote substantial alterations in algal metabolism.

This study reports for the first time the excellent nonvolatile and volatile digital memory characteristics of polymers bearing 2-pyrrolidone and succinimide moieties. A series of new polymers is synthesized from poly(ethylene-alt-maleic anhydride) and four alcohol derivatives with and without 2-pyrrolidone and succinimide moieties. All polymers, including polyvinylpyrrolidone, are found to be thermally stable up to 195 °C or higher, and characterized regarding their molecular orbital energy levels, bandgap, and resistive digital memory behaviors. Excitingly, the polymers bearing either 2-pyrrolidone or succinimide moiety demonstrate p-type digital memory behaviors with high ON/OFF current ratios and long reliabilities. Nonvolatile digital memory performance is achieved over the film thickness range of 10-80 nm, whereas volatile digital memory is demonstrated over a much narrower range of film thickness. All digital memory performances can be originated from the 2-pyrrolidone and succinimide moieties possessing high affinity and stabilization power to charges via charge traps and transformations based on a hopping conduction process. Hence, these new polymers are suitable for the production of high-performance p-type nonvolatile and volatile digital memory devices. Moreover, 2-pyrrolidone and succinimide can be used as new and economical electroactive building blocks for the development of advanced digital memory materials.

The low delivery efficiency of light-responsive theranostic nanoparticles (NPs) to target tumor sites, particularly to brain tumors due to the blood-brain barrier, has been a critical issue in NP-based cancer treatments. Furthermore, high-energy photons that can effectively activate theranostic NPs are hardly delivered to the target region due to the strong scattering of such photons while penetrating surrounding tissues. Here, a localized delivery method of theranostic NPs and high-energy photons to the target tumor using microneedles-on-bioelectronics is presented. Two types of microneedles and flexible bioelectronics are integrated and mounted on the edge of surgical forceps. Bioresorbable microneedles containing theranostic NPs deliver the NPs into target tumors (e.g., glioblastoma, pituitary adenoma). Magnetic resonance imaging can locate the NPs. Then, light-guiding/spreading microneedles deliver high-energy photons from bioelectronics to the NPs. The high-energy photons activate the NPs to treat tumor tissues by photodynamic therapy and chemotherapy. The controlled thermal actuation by the bioelectronics accelerates the diffusion of chemo-drugs. The proposed method is demonstrated with mouse tumor models in vivo.

INTRODUCTION The objective of this study was to establish the benefit of bisoprolol up-titration toward recommended dosage targets, versus lower-dose maintenance, in heart failure (HF) patients with systolic dysfunction. METHODS Korean HF patients received bisoprolol 1.25 mg/day, incrementally up-titrated toward 10 mg/day in the absence of contraindications. After 26 weeks' treatment, patients were grouped as low-dose (

Recently, the use of controlled release fertilizers in agriculture has resulted in huge benefits in plant growth and cultivation. Superabsorbent polymer (SAP)‐coated fertilizers have the added advantage in retaining water in soil after irrigation and also reduce the nutrient release rate from soil in a controlled manner. This study aimed to produce a nitrogen–phosphorus–potassium (NPK) fertilizer coated with superabsorbent carbonaceous microspheres polymer (SPC) by inverse suspension polymerization method with water‐retention and controlled release properties. Two sets of experiments were conducted: (1) three different weight percentages and (2) different materials. NPK coated with SPC showed increasing water‐retention ability with respect to carbon microsphere percentages and retains >80% water at the 30th day of experiment compared with pure NPK and NPK coated with SAP. The slow release behavior of all samples was investigated by induced coupled plasma mass spectrometry spectrometry and results showed that NPK coated with SAP and SPC has a low release rate with

Background Coronary vasospasm causes variant angina, as well as acute myocardial infarction, ventricular tachycardia, and sudden cardiac death. We evaluated morphological changes due to vasospastic lesions, which may cause acute coronary syndrome (ACS), using a novel technique called optical coherence tomography (OCT). Methods Twenty patients (40–83 years old, 19 males) with vasospasm-induced ACS who visited the emergency room because of continuous chest pain and displayed transient ST segment elevation in their electrocardiogram were enrolled in the study. None of these patients had significant coronary artery disease and all had positive results in the provocation test. OCT examinations were performed for evaluation of vasospastic lesions. Results Intraluminal thrombi and intimal erosion were found in 6 (33.3%) and 2 patients (10%), respectively. High-sensitivity C-reactive protein levels were significantly higher in patients with microthrombi (2.66 ± 3.33 mg/L) compared with those in patients without microthrombi (0.49 ± 0.30 mg/L; P = 0.022). Serum cardiac troponin-I levels were not significantly different between patients with or without microthrombi (2.37 ± 5.31 ng/mL vs. 1.45 ± 4.68 ng/mL; P = 0.704). Other parameters, including creatinine kinase–myocardial band isoenzyme, total cholesterol, pain duration, residual stenosis, lesion length, and coronary risk factors, were not significantly different between the 2 groups. Conclusion In patients with vasospasm-induced ACS, microthrombi with or without intimal erosion are major abnormal morphologic findings of OCT examinations. However, further large-scale studies are required for validation. (J Interven Cardiol 2013;26:491-500)

Acrylic pressure sensitive adhesives (PSAs) have a range of applications in industry, such as medical products, aircraft, space shuttles, electrical devices, optical products, and automobiles, etc. In this study, acrylic PSAs with fluorinated groups were synthesized using 2,2,2-trifluoroethyl methacrylate (TFMA) under UV radiation. The surface properties and adhesion strength were measured. The results showed that the addition of TFMA reduced the surface energy of the PSAs and improved the adhesion strength. POLYM. ENG. SCI., 2013. © 2013 Society of Plastics Engineers

In the present study, the curing behavior of polycardanol prepared by enzymatic oxidative polymerization of thermally treated cashew nut shell liquid, which can be available from naturally renewable resources, was explored in the presence of methyl ethyl ketone peroxide (MEKP) and cobalt naphthenate (Co-Naph). The curing behavior was monitored varying Co-Naph concentration and curing temperature by means of Fourier transform infrared (FT-IR) spectroscopy. The result revealed that the characteristic absorption bands were significantly affected by the given curing condition, resulting mainly from the unsaturated moiety in the polycardanol molecule. The extent of curing of polycardanol strongly depended on curing temperature, showing a typically sigmoidal curve reaching almost 1.0 upon processing at 200°C for 120 min. The thermal curing conditions for preparing polycardanol with an optimal state of cure were provided in the work. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The feasibility and industrial potential of using bio-flours from tropical crop residues, in particular starch containing bio-flours, for the manufacture of bio-composites was investigated. Polypropylene (PP) and poly(butylene succinate) (PBS) were compounded with bio-flours from pineapple skin (P) and from non-destarched (CS) and destarched (C) cassava root by twin-screw extrusion. In CS composites, two levels of starch granules melting were achieved by adjusting the extrusion temperature, enabling control of morphological and mechanical properties. The use of bio-flours reduced tensile strength by 26-48% and impact strength by 14-40% when the proportion of bio-flour was increased to 40% w/w, while flexural strength initially increased upon addition of bio-flours, before decreasing at higher loads. The use of compatibilizers, in particular maleic anhydride-polypropylene (MAPP) in PP composites with 30% bio-flour resulted in tensile strength similar to non-compatibilized composites with 10% bio-flour (34-35?MPa). MAPP also increased flexural strength to higher levels than pure PP, resulting in a stronger, but less flexible material.

Hydrogenated rosin epoxy methacrylate (HREM), based on hydrogenated rosin and glycidyl methacrylate (GMA), was synthesized for use as an advanced tackifier in the UV-crosslinking pressure sensitive adhesives (PSAs) system. The HREM, as a tackifier, contained UV-curing sites; thus, allowed photopolymerization to occur by UV irradiation. This UV-curable tackifier, HREM, can improve the curing rate and adhesion performance of UV-crosslinking PSAs. The characteristics of HREM were analyzed by GPC and DSC and its synthetic mechanism studied using FTIR and 1H NMR; the characteristic peaks of hydrogenated rosin and GMA vanished, but new peaks for HREM appeared. The PDI and the Tg by DSC were 1 and −25.6°C, respectively. The photopolymerization of HREM was studied using photo-DSC. Heat flow was observed during UV irradiation, and the curing rate and conversion both increased with rising photoinitiator content. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

The physicomechanical properties, thermal properties, odor, and volatile organic compound (VOC) emissions of natural-flour-filled polypropylene (PP) composites were investigated as a function of the zeolite type and content. The surface area and pore structure of the natural and synthetic zeolites were determined by surface area analysis and scanning electron microscopy, respectively. With increasing natural and synthetic zeolite content, the tensile and flexural strengths of the hybrid composites were not significantly changed, whereas the water absorption was slightly increased. The thermal stability and degradation temperature of the hybrid composites were slightly increased with increasing natural and synthetic zeolite content. At natural and synthetic zeolite contents of 3%, the various odors and VOC emissions of the polypropylene/rice husk flour and polypropylene/wood flour hybrid composites were significantly reduced because of the absorption of the odor and VOC materials in the pore structures of the natural and synthetic zeolites. These results suggest that the addition of natural and synthetic zeolites to natural-flour-filled thermoplastic polymer composites is an effective method of reducing their odor and VOC emissions without any degradation of their mechanical and thermal properties. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

The effect of wood species on the TVOC emission factor and the physico-mechanical properties of GPBs is investigated. Of the two wood species, the water absorption was higher for the GPBs made using Eucalyptus sp. than for those using Pinus massoniana. The Eucalyptus sp. GPBs pressed at room temperature, 40 and 60°C all demonstrated higher moisture absorption than commercial GPBs. The TVOC emission factor decreased with increasing press temperature, especially for Eucalyptus sp. but remained under 'excellent' grade as defined by the KACA. From these results, GPB with higher content of wood particles should be considered for the replacement of wood-based panels such as particleboard and medium density fiberboard (MDF).

The objective of this research was to investigate the miscibility behavior of melamine-formaldehyde resin and poly(vinyl acetate) blends for use as adhesives for surface materials in order to reduce formaldehyde emission. The investigation was conducted using differential scanning calorimetry, Fourier transform infrared spectroscopy, 13 C CP/MAS solid state NMR, scanning electron microscope, atomic force microscopy and wide-angle X-ray scattering. Blends of various MF resin/PVAc weight compositions, comprising 0, 30, 50, 70 and 100%, were prepared in order to determine and compare the effect of PVAc content. These blends displayed a single cure temperature over the entire range of compositions indicating that this blend system was miscible in the amorphous phase due to the formation of hydrogen bonding between the amine groups of the MF resin and the carbonyl groups of PVAc. On the surface of the cured blends, the homogeneous dispersion of the PVAc phase in the MF resin was evident as small spherical domains and the blends were confirmed to be well combined.

This study investigated the physico-mechanical properties, odor and VOC emission of bio-flour filled PP bio-composites with different pozzolan contents. On increasing the pozzolan content, the tensile and flexural strengths of the bio-composites were not significantly changed, whereas the impact strength and water absorption increased slightly and the odor intensity decreased due to the absorption of thermal degradation gases of PP and bio-flour at the pore surface of the pozzolan. The VOC emission of the bio-composites, analyzed by GC-MSD, was mainly due to PP oxidation and the thermal degradation of bio-flour during the extrusion process at high manufacturing temperatures. With increased pozzolan content, other organic compounds of the bio-composites were not significantly changed, but the toluene emission of the bio-composites was decreased. SEM and SEM/ EDX mapping techniques were employed to investigate the porous form and the pozzolan distribution in the bio-composites. From these results, we concluded that the addition of pozzolan in the bio-composites was an effective method for reducing their odor and VOC emission without any reduction in mechanical properties.

The effects of bio-scavengers on the formaldehyde emission, bonding strength, curing behavior, and thermal decomposition properties of MF resins for engineered flooring and adhesion for wood were investigated. Four varieties of bioscavengers, tannin powder, wheat flour, rice husk flour, and charcoal, were added to MF resin at 5 wt.-%. To determine formaldehyde emission and bonding strength, we manufactured engineered floorings. MF-charcoal was most effective in reducing formaldehyde emission because of its porous nature, but its bonding strength was decreased. Tannin powder and wheat flour, which contain more hydroxyl groups, showed higher bonding strength and curing degree than pure MF resin did. Although the hydroxyl groups of the bio-scavengers were effective in reducing formaldehyde emission and improve bonding strength and curing degree, rice husk flour and charcoal behaved like inorganic substances, thereby disturbing the adhesion between MP resin and wood and thus reducing the bonding strength. In thermogravimetric analysis, MF-tannin showed the highest thermal stability in the low-temperature range from 100 to 300 °C.

The effect of electron-beam (EB) irradiation on interfacial adhesion in bioflour (rice-husk flour, RHF)-filled poly(propylene) (PP) biocomposites in which either only the RHF had been EB irradiated or the whole biocomposite had been EB irradiated was examined at different EB-irradiation doses. The tensile strengths of PP-RHF biocomposites with EB-irradiated RHF and EB-irradiated PP and PP-RHP biocomposites were slightly higher than those of the nonirradiated samples. The improved interfacial adhesion of PP-RHF biocomposites with EB radiated RHP and the EB-irradiated PP-RHF biocomposites compared with the nonirradiated samples was confirmed by the morphological characteristics. In addition, the thermal stability of EB-treated biocomposites was slightly higher than those of nonirradiated samples at the irradiation doses of 2 and 5 Mrad. However, at the high irradiation dose (30 Mrad), the tensile strengths of the biocomposites were slightly decreased by main-chain scission (degradation) of PP and RHF. Attenuated total reflectance FT-IR and X-ray-photoelectron-spectroscopy findings confirmed this result by showing that that EB irradiation changed the functional groups of RHF, PP, and the biocomposites and improved the surface characteristics of the biocomposites. The thermal characteristics of the EB-irradiated PP and biocomposites were investigated using differential scanning calorimetry. From the results, we concluded that use of low-dose EB radiation increases the interfacial adhesion between matrix polymer and biofiller.

The effects of the properties of substrates and tackifier on the shear creep of SIS-based HMPSAs were investigated. The holding power (tb) and shear adhesion failure temperature (SAFT) were measured. The relationship between the complex viscosity and the holding power was examined. The holding power and SAFT values of the triblock SIS blends were higher than those of the diblock-containing SIS blends, perhaps because blends using triblock SIS have higher crossover temperature and complex viscosity than those using diblock-containing SIS. Higher levels of aromatic resin-modified aliphatic tackifier and rosin ester were found to decrease the holding power of the HMPSAs. This maybe due to the fact that rosin ester and aromatic-modified aliphatic resin are compatible with both the ends and midblocks of SIS. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 825–831, 2006

The objective of this study was the production of rice husk flour (RHF) and wood flour (WF) filled polybutylene succinate (PBS) biocomposites as alternatives to cellulosic material filled conventional plastic (polyolefins) composites. PBS is one of the biodegradable polymers, made from the condensation reaction of 1,4-butanediol and succinic acid that can be naturally degraded in the natural environment. We compared the mechanical properties between conventional plastics and agro-flour–filled PBS biocomposites. We evaluated the biodegradability and mechanical properties of agro-flour–filled PBS biocomposites according to the content and filler particle size of agro-flour. As the agro-flour loading was increased, the tensile and impact strength of the biocomposites decreased. As the filler particle size decreased, the tensile strength of the biocomposites increased but the impact strength decreased. The addition of agro-flour to PBS produced a more rapid decrease in the tensile strength, notched Izod impact strength, and percentage weight loss of the biocomposites during the natural soil burial test. These results support the application of biocomposites as environmentally friendly materials. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1513–1521, 2005

The rate constants for hydrolysis of diazomethane, diazoethane and 1-diazopropane in aqueous 5% acetonitrile at 25°C and ionic strength 1 M (NaClO4) were measured by stopped-flow spectrophotometry. The pH-rate profile for diazomethane hydrolysis exhibits a pH-independent section in the lower pH range, 8–10, with a downward break at higher pH, as has been reported for slightly different reaction conditions. In the case of diazoethane and 1-diazopropane, the reaction remains pH independent up to pH > 13. General acid catalysis of the hydrolysis reactions of diazomethane and diazoethane were examined in the pH-independent regions. For a limited number of catalysts, the value of Bronsted α was 0.58 for both diazoalkanes. The downward break in the pH rate profile for diazomethane hydrolysis is consistent with what was previously concluded, rate-limiting protonation by H2O in the pH-independent region changing to rate-limiting attack of water on the diazonium ion in the pH-dependent region, the decrease in rate constant with increasing pH being attributed to deprotonation of the diazonium ion by hydroxide ion. The lack of a downward break in the pH–rate profiles for hydrolysis of the diazoethane and 1-diazopropane is attributed specifically to the increase, relative to the methyldiazonium ion, in the rate constant for water attack on the ethyl- and 1-propyldiazonium ions, perhaps by as much as >103-fold. Copyright © 2004 John Wiley & Sons, Ltd.

This study examines the interfacial adhesion between poly(styrene) (PS) and poly(styrene-co-acrylonitrile) (SAN) interfaces reinforced with poly(styrene-co-vinyl phenol) (PS-ran-PSPh) random copolymers using an asymmetric double-cantilever beam (ADCB) test. The effects of oligomer and copolymer composition on interfacial adhesion were investigated. The results showed that the interfacial adhesion of the PS/SAN interface was increased significantly after removing the residual oligomer from the SAN. The interfacial adhesion was also measured for five-purified SAN materials in the range 17–31 wt%. The highest level of PS/SAN adhesion was observed for 17% AN (acrylonitrile) materials. In addition, the interfacial adhesion of a mixture of diblock and random copolymer was measured in order to investigate which is the most effective method. The results showed that mixture systems are more cost-effective with higher adhesion, which is independent of temperature. Atomic force microscopy showed that a single craze ahead of the crack is a possible failure mode during PS/SAN interface fracture. Copyright © 2004 Society of Chemical Industry

This work was performed to investigate the curing behaviors of Korean Dendropanax lacquer and to determine its sufficient curing conditions. In FTIR and AFM analyses, the peak area of CC (1644 cm−1) and the microadhesion decreased with increasing curing time, attributed to oxidative thermal polymerization (or crosslinking). The magnitude of the microadhesion between the probe and the surface related to the surface tack of the lacquer indicates how well the lacquer was cured and crosslinked. The increased contact angle exhibited increasing lacquer hydrophobicity, due to polymerization, during the curing process. Changes in double bond peak, contact angle, and microadhesion were dependent on the curing temperature. The results obtained by chemical and physical measures showed that Korean Dendropanax lacquer can be effectively (economically) cured at 100°C for 150 min and at 110°C for 120 min. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 625–630, 2004

The thermal behavior, thermal degradation kinetics, and pyrolysis of resol and novolac phenolic resins with different curing conditions, as a function of the formaldehyde/phenol (F/P) molar ratio (1.3, 1.9, and 2.5 for the resol resins and 0.5, 0.7, and 0.9 for the novolac resins) were investigated. The activation energy of the thermal reaction was studied with differential scanning calorimetry at five different heating rates (2, 5, 10, 20, and 40°C/min) between 50 and 300°C. The activation energy of the thermal decomposition was investigated with thermogravimetric analysis at five different heating rates (2, 5, 10, 20, and 40°C/min) from 30 to 800°C. The low molar ratio resins exhibited a higher activation energy than the high molar ratio resins in the curing process. This meant that less heat was needed to cure the high molar ratio resins. Therefore, the higher the molar ratio was, the lower the activation energy was of the reaction. As the thermal decomposition of the resol resins proceeded, the activation energy sharply decreased at first and then remained almost constant. The activation energy of the thermal decomposition for novolac resins with F/P = 0.5 or F/P = 0.7 was almost identical in all regions, whereas that for novolac resins with F/P = 0.9 gradually decreased as the reaction proceeded. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2589–2596, 2003

The rates of solvolysis of 1,1-diarylethyl p-nitrobenzoates and chlorides were determined conductimetrically at 25 °C in 80% (v/v) aqueous acetone. Applying the Yukawa–Tsuno (Y–T) equation, the symmetrical (X = Y) subseries gave a precise additivity relationship for the whole substituent range with a ρsym value of −3.78 and an rsym value of 0.77. While any Y subsets gave statistically less reliable Y–T correlations, the apparent ρ value changed significantly depending on the fixed Y substituents; the ρ value decreases with the more electron-donating fixed substituents Y, which is compatible with the Hammond shift of the transition state coordinate. Nevertheless, the concave correlations of the More O'Ferrall non-linearity relationship for any Y subsets are not in line with what is expected from the reactivity–selectivity relationship suggesting an anti-Hammond shift of transition state. However, we found a precise extended Bronsted relationship between the pK values of 1,1-diarylethylenes and solvolysis rate process with a constant slope of α = 1.03 ± 0.03. This is direct evidence indicating that there is no significant shift of the transition-state coordinate over the whole range of substituent change. Copyright © 2002 John Wiley & Sons, Ltd.

The substituent effects on the solvolysis of 1-X-phenyl-1-Y-phenyl-2,2,2-trifluoroethyl tosylates were analyzed on the basis of the Yukawa–Tsuno equation. For the solvolysis of the symmetrically disubstituted X = Y subseries, an excellent linear correlation was obtained. However, in the solvolyses of series of varying X with a fixed-Y subset, the substituent effects were found to give significantly concave Y–T correlations. The ρ value for the Y–T correlations changes significantly with the fixed Y substituent. There is a qualitative trend of a linear decrease in the ρ value as the fixed-Y substituent of the respective subset becomes more electron donating. The non-linearity of substituent effects was attributed to a substituent-induced conformational change of the transition state, which could be simulated by calculation of the preferred conformation of the intermediate carbocation. A molecular orbital optimization method was applied to determine the preferred conformations of the α,α-diarylcarbenium ions derived from the title systems. The symmetrical carbenium ions X = Y have a preferred propeller shape conformation with twist angles differing by 14° (Econformation), whereas in the unsymmetrical systems X ≠ Y the two aryl rings are much more (>30°) differently twisted in the preferred conformation (PTconformation). The linear correlation found for the symmetrical subseries is essentially an outcome of the Econformation of the transition state. In unsymmetrical cases, the substituent effect correlation in any Y subset should reflect the conformational arrangements, EX, PX and TX of the variable X-aryl group, depending on relative σ values of X and Y. The substituent effects in the Y-subsets were successfully treated by three different Y-independent correlations for the preferred conformational arrangements: E correlation for substituents when (σX − σY) ≅ 0, PX correlation when (σX − σY) ≪0 and TX correlation for the (σX − σY) ≫0 class, respectively. Copyright © 2002 John Wiley & Sons, Ltd.

The effect of paper sludge's particle size and extrusion temperature on the physical and mechanical properties of paper sludge–thermoplastic polymer composites was investigated. In the experiment three levels of particle sizes for the paper sludge and four extrusion temperatures were designed to examine the physical and mechanical properties of these composites. The ash contents of the paper sludge were about 73.7, 46.2, and 38.1% with particle sizes of below 0.15, 0.18–0.25, and 0.42–0.84 mm, respectively, which meant lower ash content and higher cellulose fiber content, in the larger particle size of paper sludge. As the particle size of the paper sludge decreased, the swelling thickness, water absorption, and tensile and flexural strengths of the composite improved; but the particle size of the paper sludge had no effect on its unnotched impact strength. With the increase of the extrusion temperature the thickness swelling and water absorption of the composites were slightly improved but not statistically different. A rise of the extrusion temperature generally had a positive effect on the tensile and flexural properties of the composite. The notched and unnotched impact strengths of the composite increased with the increase of the extrusion temperature from 190 to 230°C, but they decreased slightly at an extrusion temperature of 250°C. This low impact energy at an extrusion temperature of 250°C may be attributed to the excessively brittle fibers from thermal decomposition. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2709–2718, 2001

The γ-silicon effects in solvolyses were studied mechanistically on 3-(aryldimethylsilyl)propyl tosylates in various solvents based on the substituent effects. The mechanism can be described as competing reactions of the γ-silyl-assisted (kSi) and the solvent-assisted (ks) pathways. Copyright © 2000 John Wiley & Sons, Ltd.

Relationship between the miscibility of pressure-sensitive adhesives (PSAs) acrylic copolymer/hydrogenated rosin systems and their performance (180° peel strength, probe tack, and holding power), which was measured over a wide range of time and temperature, were investigated. The miscible range of the blend system tended to become smaller as the molecular weight of the tackifier increased. In the case of miscible blend systems, the viscoelastic properties (such as the storage modulus and the loss modulus) shifted toward higher temperature or toward lower frequency and, at the same time, the pressure-sensitive adhesive performance shifted toward the lower rate side as the Tg of the blend increased. In the case of acrylic copolymer/hydrogenated rosin acid systems, a somewhat unusual trend was observed in the relationship among the phase diagram, Tg, and the pressure-sensitive adhesive performance. Tg of the blend was higher than that expected from Tgs of the pure components. This trend can be due to the presence of free carboxyl group in the tackifier resin. However, the phase diagram depended on the molecular weight of the tackifier. The pressure-sensitive adhesive performance depended on the viscoelastic properties of the bulk phase. A few systems where a single Tg could be measured, despite the fact that two phases were observed microscopically, were found. The curve of the probe tack of this system shifted toward a lower rate side as the Tg increases. However, both the curve of the peel strength and the holding power of such system did not shift along the rate axis. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 651–663, 1999

In response to the strong industry need for cost reduction DuPont has been developing a new breakthrough technology including materials, equipment and process which comprise a system for manufacturing LCD Color Filters. This new technology significantly reduces process steps and clean room space required by conventional photolithography, thereby providing significant capital and operational savings. Since the system is based on digital technology, the direct writing precision patterning process eliminates photomasks for RGB, is highly scalable and greatly simplifies pattern change over.

The relationship between the miscibility of acrylic pressure-sensitive adhesive (PSA) and the fracture energy (W) (Jm−2) of the probe tack was investigated, wherein the master curve of W was compared with that of the maximum force (σmax) (gf) of the probe tack. It was ascertained that W of acrylic PSA was closely related to the miscibility between the components (acrylic copolymer and tackifier resin). In the case of the miscible blend system, the master curve of W shifted toward the lower rate side and, at the same time, the magnitude decreased as the tackifier resin content increased. The degree of the shift of W was extremely smaller than that of σmax. In the case of the immiscible blend system, the master curve of W remarkably decreased as the tackifier resin content increased, which suggests the fact that W of the PSA depended on the dynamic mechanical properties of the matrix phase and that the resin-rich phase acted as a kind of filler, thus reducing the practical performance. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 581–587, 1998

The miscibility between an acrylic copolymer and a tackifier resin was investigated in terms of phase diagrams, glass transition temperatures (Tg's), and dynamic mechanical properties of blends. Shear creep resistance (holding power, tb) of the blends was measured as a function of both temperature and stress (σ0) in order to obtain the master curves. It was found that the shear creep resistance of the pressure-sensitive adhesives (PSAs) was closely related to the miscibility between the components and viscoelastic properties of the blends. The master curve of the miscible blends shifts toward a longer time scale as the amount of tackifier resin in the blend is increased as a result of the modification of the bulk properties, and their behavior greatly depends on the glass transition temperature (Tg) and storage modulus (G′) of the blends. However, the master curve of immiscible blends where two phases exist in the system does not shift greatly toward a longer time scale, because Tg and the storage modulus of the blend do not change greatly. © 1995 John Wiley & Sons, Inc.

This work introduces a novel silver composite cathode with a surface coating of scandia-stabilized zirconia (ScSZ) nanoparticles for application in intermediate temperature solid oxide fuel cells (IT-SOFCs). The ScSZ coating is expected to maximize the triple boundary area of the Ag electrode, ScSZ electrolyte, and oxygen gas, where the oxygen reduction reaction occurs. The coating also protects the porous Ag against thermal agglomeration during fuel cell operation. The ScSZ nanoparticles are prepared by sputtering scandium-zirconium alloy followed by thermal oxidation on Ag mesh. The performance of the solid oxide fuel cells with a gadolinia-doped ceria electrolyte support is evaluated. At temperatures

A series of acrylic copolymers, poly(butyl acrylate-co-acrylic acid), were blended with tackifiers and dehydroabietic acid esters, and the miscibility between the components was investigated. The phase diagram of the blends changed from an LCST type to a UCST type as acrylic acid content increased, and the miscibility region in the phase diagrams decreased as the tackifier became bulkier. It was found that some of the trends can be accounted for on the basis of mean field approximation. © 1995 John Wiley & Sons, Inc.

Influence of miscibility between the components in acrylic pressure-sensitive adhesives upon their peel strength P as a function of temperature has been studied. In case of miscible blend systems, incorporation of tackifier resins into the pressure-sensitive adhesive systems results in the modification of the bulk properties, including Tg, and a plot of P against ΔT gives a smooth master curve, where ΔT is defined as the difference between the temperature of peel test and Tg of the blend. However, in case of immiscible blends where two phases exist in the system, no master curve can be obtained, and P of an acrylic copolymer decreases as the tackifier content increases. In this case, physical properties and adhesive performance will be governed by a matrix phase, and a dispersed phase will act as a filler. © 1995 John Wiley & Sons, Inc.