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1.
Polyurethane (PU) films containing different amounts of fly ash particles (FAPs) were prepared by simple solution casting method. The morphological, thermal, and mechanical properties of the composite films were investigated by several characterization methods. Results show that sufficient amounts (up to 40 wt%) of FAPs can be incorporated throughout the film. The presence of FAPs within PU film not only acts as filler to increase the mechanical strength of the film but also increases its volatile organic compounds (VOCs) adsorption capacity. The VOCs adsorption capacity of FAPs/PU composite films were investigated on three different compounds (chloroform, toluene, and benzene). It showed consistent trend in the order of toluene > benzene > chloroform for all the samples. The VOCs adsorption capacity of PU film was found to be increased by two fold when 20 wt% of FA was incorporated through it. The present results suggest the potential use of FAPs as filler materials for PU films with improved VOCs adsorption from outdoor and indoor air. 相似文献
2.
Split-type nylon/polyester microfiber and polyester microfiber fabrics possess drapeability, softness, bulkiness, and smoothness,
so that they can be applied in various industrial fields. In particular, these fabrics are able to absorb various organic
solvents, and can be used as clean room materials. To investigate the chemical affinity between solvents and the compositional
materials of these fabrics, the contact angle of thermally pressed film fabrics was measured with different solvents. The
thermally pressed nylon/polyester fabric films showed a chemical attraction to formamide. The sorption properties of the microfiber
fabrics were investigated using a real time testing device, and these tests showed that the sorption behavior was more influenced
by the structure of the fibrous assembly than by any chemical attraction. The effect of the fabric density, specific weight,
and sample structure on the sorption capacity and rate was examined for various organic solvents. The sorption capacity was
influenced by the density and the specific weight of the fibrous assembly, and knitted fabric showed a higher sorption capacity
than woven fabric. However, the sorption rate was less affected in lower viscosity solvents. On applying Poiseuille’s Law,
the lower viscosity solvents showed higher initial sorption rates, and more easily penetrated into the fibrous assembly. 相似文献
3.
Electropolymerization of carbazole (Cz) by cyclic voltammetry (CV) onto carbon fiber microelectrodes (CFME) (diameter ∼7 μm)
in dichloromethane (CH2Cl2) solution of 0.1 mol·dm−3 tetraethyl ammonium perchlorate (TEAP) results in the formation of polycarbazole (PCz) thin film coatings. CV results showed
that these PCz thin films have reversible redox behavior in monomer-free electrolyte solution. The resulting thin polymer
films were characterized using Fourier transform infrared attenuated total reflectance spectroscopy (FTIR-ATR) and atomic
force microscopy (AFM). Results performed at optimum experimental conditions indicate that electrodes show a reversible and
stable behavior over sixty eight days of testing for dopamine in 100 μmol·dm−3 buffer solution. A detection limit for PCz thin films as low as 0.1 μM (3S/N) was obtained for the polycarbazole (PCz) thin
films formed using CV. Hence, this novel sensor can be considered as promising sensor for dopamine detection. 相似文献
4.
Edible films have been used for decades on fresh produce to create a semipermeable membrane on the surface to suppress respiration, control moisture loss, and more recently to provide a delivery mechanism for the inclusion of functional components. Scientists at the Southern Regional Research Center (SRRC) have previously demonstrated that a thin biodegradable film can be produced from soapstock, an underused byproduct from the vegetable oil industry. After physical and chemical treatments, a thin film was produced from various soapstocks (cottonseed and safflower). Different hydration ratios were tested since the initial soapstock solutions were rather viscous. To examine the potential use of an oilseed-derived lipid film for the extension of shelf life, different types of the oilseed-derived soapstocks were utilized to produce lipid films with different hydration ratios, and containing 0, 5, and 10% of paraffin wax for application on ‘Camelot’ bell peppers. Control bell peppers lost almost 25% weight per unit surface area (SA) in 78 h when stored under ambient conditions. Cottonseed film-coated peppers, hydrated at 1:4, lost only about 5% moisture per unit SA after 78 h and minimized weight loss by up to 79% compared to the control. However, since a 1:4 hydration ratio remained rather viscous, 1:8 was preferred and these cottonseed films reduced weight loss per unit SA by up to 48% during storage. Safflower-derived soapstock film resulted in the least effective water retention of the films and ratios tested, with roughly 21–25% reduction in weight loss per SA compared to controls. Safflower-derived soapstock was higher in unsaturated fatty acids, which are less efficient to control moisture migration because they are more polar than saturated lipid materials, as contained in cottonseed-derived materials. Addition of wax to the cottonseed-derived films decreased water loss slightly, similar to previous reports in the literature. An ANOVA supported the conclusion that the oilseed-derived lipid films significantly reduced moisture loss across the produce epidermis. To avoid potential allergenicity concerns in cottonseed soapstock, additional cleanup steps and tests with commonly used edible coating additives would be required before attaining food grade status. 相似文献
5.
Giryong Park Yeonsu Jung Geon-Woong Lee Juan P. Hinestroza Youngjin Jeong 《Fibers and Polymers》2012,13(7):874-879
A method for manufacturing sheath-core structured fibers was developed using wet spinning techniques. The core portion of a fiber was prepared using a carbon nanotube (CNT) solution while the sheath used a fiber-forming polymer such as polyvinyl alcohol (PVA). Preparation methods of CNT solutions were investigated and it was found that dispersivity and concentration played an important role in the formation and spinning of fiber??s core. CNT solution prepared using a surfactant with high molecular weight such as sodium lignosulfonate (SLS) was most effective and the CNT concentration was as high as 30 g/l. Fiber processing conditions were optimized and it was determined that stretching fibers in the coagulation bath was a significant step in the formation of a solid and well structured core. Drawn fibers were so strong and flexible that they could be woven into a fabric for potential use as a pressure sensor. These results are relevant for practical applications, such as the development of large-area fabric sensors. Furthermore, the described procedure to produce sheath-core CNT fibers is scalable as wet spinning methods have been widely used in the fiber industry. 相似文献
6.
Jin Zhang Yibing Cai Xuebin Hou Cong Huang Hui Qiao Qufu Wei 《Fibers and Polymers》2017,18(2):253-263
Porous cellulose acetate (CA) films by breath figure (BF) incorporated with capric acid as form-stable phase change materials (PCMs) were fabricated and characterized for storing and retrieving thermal energy. Effects of different solvents, CA concentration and film thickness on morphology, microstructure and thermal energy storage property of formstable PCMs were investigated by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area analyzer and differential scanning calorimetry (DSC), respectively. The results indicated that the prepared CA films were porous with DMF, acetone, and dichloromethane (DCM) as the solvents, and capric acid absorption capacity was as high as 86.9, 75.0 and 82.2 % with the specific surface area of 4.8, 2.8 and 1.8 m2/g. Moreover, porous CA film with 5 % CA concentration and 0.5 mm thickness prepared by using DMF as solvent had larger specific surface area and higher thermal energy storage properties. The fabricated form-stable PCMs could well maintain their PCM characteristics and demonstrated great temperature regulation ability and had potential applications in building energy conservation. 相似文献
7.
The multi-walled carbon nanotube (MWNT)/cellulose nanocomposites were prepared by using monohydrated Nmethylmorpholine-N-oxide (NMMO) as a solvent for dispersing the acid-treated MWNTs (A-MWNTs) as well as for dissolving the cellulose. The A-MWNTs were well dispersed in both monohydrated NMMO and the nanocomposite films. The nanocomposite films were prepared by a film-casting method onto a glass plate. The tensile strain at break, Young’s modulus, and toughness of nanocomposite films increased by ～5, ～2 and ～12 times, respectively at ? (A-MWNT content in the nanocomposite)=0.8 wt%, as compared to those of the pure cellulose film. The thermal degradation temperature of the nanocomposite films also increased from 329 to 339 oC by incorporation of 1 wt% A-MENTs. The electric conductivities of the A-MWNT/cellulose nanocomposites at ? =1 and 10 wt% were 2.09×10?5 and 3.68×10?3 S/cm, respectively. The transmittances were 86, 69 and 55 % at 550 nm for 0.4, 0.8 and 1 wt% nanocomposite films, respectively. Thus, these nanocomposites are promising materials in terms of all the properties studied in this paper and can be used for many applications, such as toughened cellulose fibers, transparent electrodes, etc. 相似文献
8.
Celite powder surface-modified with cationic surfactant was used to make polyethylene (PE) specialty film that can be contrasted
with ordinary film in having high odor storing capacity and long odor lasting period. Mechanical properties of the films were
sacrificed as more celite particles were included, whether celite surface was modified or not. The film with CTAB-modified
celite showed the best odor storing and lasting properties for five different flavors ofodor, three artificial and two natural
ones, among the kinds of films developed. Comparisons among the different films are made, together with brief discussion about
the reason for differences in odor lasting period and possible application to packaging industry. 相似文献
9.
The purpose of this work is to explore effective means of fabricating nanostructure-deposited continuous woven carbon fabric and to investigate the feasibility of using this material in structural battery applications. In order to prove this concept, two types of nanostructured carbon fabric electrodes – one with vertically-aligned carbon nanotubes (VACNTs) formed directly on carbon fabric utilizing iron (Fe) nanoparticles and Al buffer layers, the other with the same VACNTs on a chemical vapor-deposited graphene surface utilizing Ni seed layers on the carbon fabric – were fabricated to investigate material electrical performances as battery electrodes. The reversible specific capacity of 250 mAh/g on average at C/20 with good cyclic retention in these three all-carbon electrodes, including pristine carbon fabric, suggests a promising structural battery electrode for low-current battery applications. Even though the capacity of VACNT-grafted carbon fabrics was limited due to poor wetting of the VACNT forest with electrolyte caused by the lack of functionalization of the VACNT, their excellent cyclic performances and galvanostatic curves support the idea that the carbon nanotube and carbon fabric combination can be utilized in battery applications. However, pristine-carbon fabric is still a good candidate for battery applications because of its simplicity of mass production. 相似文献
10.
Nanocellulose reinforced PVA composite films: Effects of acid treatment and filler loading 总被引：1，自引：0，他引：1
Sun-Young Lee D. Jagan Mohan In-Aeh Kang Geum-Hyun Doh Soo Lee Seong Ok Han 《Fibers and Polymers》2009,10(1):77-82
Nanocellulose was prepared by acid hydrolysis of microcrystalline cellulose (MCC) at different hydrobromic acid (HBr) concentrations.
Polyvinyl alcohol (PVA) composite films were prepared by the reinforcement of nanocellulose into a PVA matrix at different
filler loading levels and subsequent film casting. Chemical characterization of nanocelluloses was performed for the analysis
of crystallinity (Xc), degree of polymerization (DP), and molecular weight (Mw). The mechanical and thermal properties of the nanocellulose reinforced PVA films were also measured for tensile strength
and thermogravimetric analysis (TGA). The acid hydrolysis decreased steadily the DP and Mw of MCC. The crystallinity of MCC with 1.5 M and 2.5 M HBr showed a significant increase due to the degradation of amorphous
domains in cellulose. Higher crystalline cellulose showed the higher thermal stability than MCC. From X-ray diffraction (XRD)
analysis, nanocellulose samples showed the higher peak intensity than MCC cases. Reduction of MCC particle by acid hydrolysis
was clearly observed from scanning electron microscope (SEM) images. The tensile and thermal properties of PVA composite films
were significantly improved with the increase of the nanocellulose loading. 相似文献
11.
Poly(methyl methacrylate-glycidiyl methacrylate) p(MMA-GMA) film was fabricated by UV initiated photo-polymerization. Iminodiacetic acid ligand (IDA) was covalently immobilized to the p(MMA-GMA) film via ring opening reaction of epoxy groups. Cu(II) ion was chelated with the immobilized ligand. The morphology and properties of the films were characterized with SEM, FTIR, AFM, water content, the specific surface area, and contact angle. HSA (human serum albumin) was used as a model protein to describe the adsorption propency of the support. The information obtained in this research will serve for scaling up the process in industrial applications. The HSA adsorption capacity of the metal chelated film was found to be 2.7 mg/cm2 film. The p(MMA-GMA)-IDA-Cu(II) films exhibited a high adsorption capacity and fast adsorption rate compared to Cu(II) ion free counterpart. 相似文献
12.
Junyoung Song Soyoung Kim Sora Yoon Daehwan Cho Youngjin Jeong 《Fibers and Polymers》2014,15(4):762-766
A surfactant is used to enhance spinnability of carbon nanotube (CNT) fibers during direct spinning via chemical vapor deposition (CVD). In this study, the non-ionic surfactant, polysorbate, is used due to its good solubility in the CNT synthesis solution. The addition of the surfactant increased the specific strength and electrical conductivity of CNT fibers. Due to these enhanced properties, CNT fibers can be spun at higher speeds which results in lower linear density. These enhancements are due to the reduced agglomeration of iron catalysts during the synthesis of CNT fibers via CVD. This simple approach may create new applications for CNT fibers, such as for artificial muscles and power cables. 相似文献
13.
Yafang Li Xiaomin Ma Nanping Deng Weimin Kang Huihui Zhao Zongjie Li Bowen Cheng 《Fibers and Polymers》2017,18(2):212-220
The nanofiber membrane prepared by electrospinning has been widely applied in lithium-ion batteries. A powerful strategy for designing, fabricating and evaluating Poly-m-phenylene isophthalamide (PMIA) nanofiber membrane with SiO2 nanoparticles was developed by electrospinning in this paper. The morphology, crystallinity, thermal shrinkage, porosity and electrolyte uptake, and electrochemical performance of the SiO2/PMIA nanofiber membranes were investigated. It was demonstrated that the nanofiber membrane with 6 wt% SiO2 possessed notable properties, such as better thermal stability, higher porosity and electrolyte uptake, resulting in higher ionic conductivity (3.23×10-3 S·cm-1) when compared with pure PMIA nanofiber membrane. Significantly, the SiO2/PMIA nanofiber membrane based Li/LiCoO2 cell exhibited more excellent cycling stability with capacity retention of 95 % after 50 cycles. The results indicated that the SiO2-doped PMIA nanofiber membranes had a potential application as separator in high temperature resistance lithium-ion batteries. 相似文献
14.
In this work, 9-benzyl-9H-carbazole (BzCz) monomer was chemically synthesized by a new process. It was electrocoated on carbon fiber microelectrode
(CFME) as an active electrode material in 0.1 M sodium perchlorate (NaClO4)/acetonitrile (ACN) solution. The electropolymerization process was successfully performed less amount of 3 mM. The characterization
of Poly(BzCz)/CFME thin films was performed by Fourier transform infrared reflectance-attenuated total reflection spectroscopy
(FTIR-ATR) and Electrochemical impedance spectroscopy (EIS). The effects of monomer concentrations (1, 2, and 3 mM) during
the preparation of modified electrodes were examined by EIS. Capacitive behaviors of modified CFMEs were defined via Nyquist,
Bode-magnitude and Bode-phase plots. Variation of capacitance values by initial monomer concentration and specific capacitance
values are presented. The highest specific capacitance value for a potensiodynamically prepared polymer thin film in the initial
monomer concentration of 1 mM with a charge of 4.54 mC cm−2 was obtained about 221.4 μF cm−2. An equivalent circuit model, R(C(R(QR)))(CR), for different concentrations of Poly(BzCz). CFME was proposed and experimental
data were simulated to obtain the numerical values of circuit components. 相似文献
15.
In the present study, nanofibrils of cellulose are extracted from waste jute fibers using high energy planetary ball milling process in wet condition. The rate of refinement of untreated fibers having non-cellulosic contents was found slower than treated fibers due to strong holding of fiber bundles by non-cellulosic contents. At the end of three hours of wet milling, untreated fibers were refined to the size of 850 nm and treated fibers were refined to the size of 443 nm. In the subsequent stage, composite films of poly lactic acid (PLA) were prepared by solvent casting with 3 wt% loading of untreated jute nanofibrils, treated jute nanofibrils and microcrystalline cellulose. The influence of non-cellulosic contents on mechanical properties of PLA films are investigated based on results of tensile test, dynamic mechanical analysis and differential scanning calorimetry. The maximum improvement was observed in case of treated jute nanofibril/PLA composite film where initial modulus and tensile strength increased by 207.69 % and 168.67 %, respectively as compared to neat PLA film. These improvements are attributed to the increased interaction of treated jute nanofibrils with PLA matrix due to their higher precentage of cellulosic contents and mechanically activated surface. 相似文献
16.
Akif Kaynak 《Fibers and Polymers》2009,10(5):590-593
Long term performance of conductivity of p-toluene sulfonic acid (pTSA) doped electrochemically synthesized polypyrrole (PPy) films was estimated from accelerated aging
studies between 80 °C and 120 °C. Conductivity decay experiments indicated that overall aging behavior of PPy films deviated
from first order kinetics at prolonged aging times at elevated temperatures. However, an approximate value for the activation
energy of the conductivity decay of PPy was calculated as E=47.4 kJ/mol, enabling an estimate of a rate constant of k=8.35×10−6/min at 20 °C. The rate of decrease of conductivity was not only temperature dependent but also influenced by the dopant concentration.
A concentration of 0.005 M pTSA in the electrolyte resulted in a conductive film and when this film was exposed to 120 °C
for a period of 40 h, the conductivity decayed to about 1/20 of its original value. The concentration of pTSA was increased
to 0.05 mol/l and when the resulting film was aged in the same way, it showed a decrease in the conductivity to about 1/3
of its original value. Both microwave transmission and dc conductivity data revealed that highly doped films were considerably
more electrically stable than lightly doped films. The dopant had a preserving effect on the electrical properties of PPy. 相似文献
17.
Tae-Won Son Jong-Hwan Kim Woo-seung Lee Jae-hoon Park Young-Sic Kang 《Fibers and Polymers》2013,14(4):653-659
Poly (m-phenylene isophthalamide) (PMIA), one of the most important aromatic polyamides, has been widely used due to its high thermal resistivity combined with its excellent mechanical properties. PMIA also has superior electrical properties. Meta-linked aromatic polyamide was synthesized by solution polymerization of m-phenylene diamine with isophthaloyl chloride in a polar organic solvent, such as dimethylacetamide (DMAc). When forming PMIA films, properties of films can differ according to DMAc contents in polymers. Thus, DMAc as a PMIA solvent was evaporated using a drying process at 80 °C for two hours. By contrast, we included other control groups. In one group, dried film was stretched to its maximum length. And, in another group, film was stretched and heat treated at 200 °C for 10 min. Therefore, using this method, these films were prepared at each concentration. For analysis of their properties, PMIA films were prepared in the same way; properties of PMIA films were investigated through analysis of Instron, XRD, FT-IR, SEM, and TGA. Results of these analyses will provide information on optimized mechanical and thermal conditions for use of poly (m-phenylene isophthalamide) film derived from m-phenylene diamine and isophthaloyl chloride using dimethylacetamide (DMAc) as a solvent. 相似文献
18.
In recent years, there has been a great demand for artificial materials for biomedical applications, especially to bone growth. In the present study, the in vitro bioactivity of chitosan-acetylated jute blended film was investigated through biomimitic growth of bone-like apatite layer formation in simulated body fluid (SBF) on the surface of the film. Chitosan was prepared from crab shells and the blended film was prepared by solvent casting method using 10 % formic acid aqueous solution of in-house chitosan and mercerized, acetylated jute fiber. Water absorption characteristics (swelling test) and tensile strength (Universal testing machine) of the films were determined. Thermal behavior of the films were examined by TGA analysis. The biocompatibility of the chitosan-acetylated jute (CAJ) film was indicated by the formation of hydroxy apatite (HAp) bone-like layer formed on the surface when soaked in SBF solution for 14 days. The topography of the film was characterized by scanning electron microscope (SEM) and Ca/P ratio of the apatite layer was confirmed to be 50:50 by EDX analysis. The results showed that the CAJ film will be a promising bone substituting material. 相似文献
19.
20.
Numerous gluten preparations were produced by the variation of pressure and temperature. Optimal conditions for the production of gluten films on a laboratory-scale were by suspending of gluten (1 g) in a mixture of ethanol (3 mL), glycerol (0.5 g) and conc. formic acid (10 mL), casting and drying at 40 °C. Small-scale laboratory methods for the production of gluten films by casting and moulding were developed. Film strips obtained were examined by micro-extension tests, which resulted in curves similar to extensigrams for dough and gluten and allowed the determination of the resistance to extension, extensibility and elasticity. The results demonstrated that pressure treatment of gluten in combination with variable cultivars, temperature, process parameters and additives, allow the production of films with a wide range of rheological properties – from soft and smooth to strong and hard rubber like. Finally, it was demonstrated that the addition of fibres to gluten enhanced the stability of films. Thus, high pressure treatment allows a selective modification of gluten as raw material for film production. In comparison with conventional plastic films, gluten films have considerable advantages, because they can be produced from renewable plants and they are readily biodegradable. 相似文献