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Preparation of Porous Carbon by Polymer Blending of Phenolic Resin and Adipic Diacid  [PDF]
XIA Xiao-Hong, LIU Hong-Bo, HUANG Yan-Rui, YANG Li, SHI Lei
无机材料学报 , 2011, DOI: 10.3724/sp.j.1077.2011.00857
Abstract: Porous carbons used for electric double layer capacitors (EDLCs) were prepared by chemical blending of phenolic resin (PF) and adipic diacid (DA). Chemical reaction of PF with diacid is manifested by a shift of carbonyl stretching peak of diacid to a higher frequency in FT―IR spectra and a higher decomposition temperature of diacid in TG curves. The influences of the ratio of w(DA) to w(PF) on pore structure, adsorption behavior and capacity performance were investigated. The specific surface area and total pore volume increase with the ratio of w(DA) to w(PF) at first and then decrease, reach the maximum at the value of w(PF)/w(DA), which are 550 cm2/g and 0.27 cm3/g, respectively. When the porous carbon used for the electrodes of electrochemical double layer capacitor (EDLC), a satisfied speci―c capacitances of 145 F/g in 30 wt% KOH aqueous electrolytes is acquired and the capacitance maintenance achieve 70% while the current density enlarged 50 times.
Preparation and thermal properties of mesoporous silica/phenolic resin nanocomposites via in situ polymerization
C. Wei,C. B. Yu,J. Lv,H. X. Liu
eXPRESS Polymer Letters , 2012, DOI: 10.3144/expresspolymlett.2012.84
Abstract: In order to enhance the adhesion between inorganic particles and polymer matrix, in this paper, the mesoporous silica SBA-15 material was synthesized by the sol-gel method. The surface of SBA-15 was modified using γ-glycidyloxypropyltrimethoxysilane (GOTMS) as a coupling agent, and then mesoporous silica/phenolic resin (SBA-15/PF) nanocomposites were prepared via in situ polymerization. The structural parameters and physical properties of SBA-15, SBA-15-GOTMS (SBA-15 surface treated using GOTMS as coupling agents) and E-SBA-15/PF (SBA-15/PF nanocomposites extracted using ethanol as solvent) were characterized by X-ray diffraction (XRD), N2 adsorption-desorption, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA). The thermal properties of the nanocomposites were studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The results demonstrated that the GOTMS were successfully grafted onto the surface of SBA-15, and chemical bonds between PF and SBA-15-GOTMS were formed after in situ polymerization. In addition, it is found that the in situ polymerization method has great effects on the textural parameters of SBA-15. The results also showed that the glass transition temperatures and thermal stability of the PF nanocomposites were obviously enhanced as compared with the pure PF at silica contents between 1–3 wt%, due to the uniform dispersion of the modified SBA-15 in the matrix.
A PHENOLIC RESIN WITH HIGHER CARBON CONTENT AND LOWER MODULUS
高碳含量低模量的酚醛树脂

Yu Shang-ying,Shi Mei-yuan,Wu Yao-man,Huang Zhi-tang,
喻商英
,史美缘,吴瑶曼,黄志镗

高分子学报 , 1980,
Abstract: A kind of thermosetting phenolic resin was prepared by the condensation of linear phenolic resin (Novolak) with formaldehyde. It exhibts higher carbon content lower modulus and similar thermal stability as compared with ordinary thermosetting phenolic resin, and can be used for preparation of composites.
Polybutylacrylate/poly(methyl methacrylate) Core-Shell Elastic Particles as Epoxy Resin Toughener: Part I Design and Preparation
Jianli WANG,Myonghoon LEE,Xiaomei YU,Jianbin JI,Kejian YAO,
Myonghoon
,LEE

材料科学技术学报 , 2004,
Abstract: Polybutylacrylate (PBA)/poly(methyl methacrylate) (PMMA) core-shell elastic particles (CSEP), whose rubbery core diameter ranged from 0.08 μm to 1.38μm, were synthesized by using conventional emulsion polymerization, multi-step emulsion polymerization, and soapless polymerization. Allyl methacylate (ALMA) and ethylene glycol dimethacrylate (EGDMA) were selected as crosslinking reagents for core polymerization. Methacrylic acid (MAA) was used as functional co-monomer with methyl methacrylate as shell component. The content of vinyl groups in PBA rubbery core increased with the amount of crosslinking reagents. The core-shell ratio affected great on the morphology of the complex particles. Furthermore, the amounts of carboxyl on the surface of core-shell particles, copolymerized with acrylic acid, were determined by potentiometric titration. Results showed that methylacrylic acid was distributed mostly on the surface of particles.
Synthesis of a boron modified phenolic resin  [PDF]
Aparecida M. Kawamoto,Luiz Cláudio Pardini*,Milton Faria Diniz,Vera Lúcia Louren?o
Journal of Aerospace Technology and Management , 2010,
Abstract: Phenolic resin has long been used as matrix for composites mainly because of its flame retardant behavior and high char yield after pyrolysis, which results in a self supporting structure. The addition of ceramic powders, such as SiC and B4C, as fillers to the phenolic resin, results in better thermo-oxidative stability, but as drawbacks, it has poor homogeneity, adhesion and processing difficulties during molding of the composites. The addition of single elements, such as boron, silicon and phosphorus in the main backbone of the thermo-set resin is a new strategy to obtain special high performance resins, which results in higher mechanical properties, avoiding the drawbacks of simply adding fillers, which results in enhanced thermo-oxidative stability compared to conventional phenol-formaldehyde resins. Therefore, the product can have several applications, including the use as ablative thermal protection for thermo-structural composites. This work describes the preparation of a boron-modified phenolic resin (BPR) using salicyl alcohol and boric acid. The reaction was performed in refluxing toluene for a period of four hours, which produced a very high viscosity amber resin in 90% yield.The final structure of the compound, the boric acid double, substituted at the hydroxyl group of the aromatic ring, was determined with the help of the Infrared Spectroscopy, 1H-NMR, TGA-DSC and boron elemental analysis. The absorption band of the group B-O at 1349 cm ˉ1 can be visualized at the FT-IR spectrum. 1H-NMR spectra showed peaks at 4.97-5.04 ppm and 3.60-3.90 ppm assigned to belong to CH2OH groups from the alcohol. The elemental analysis was also performed for boron determination.The product has also been tested in carbon and silicon fibers composite for the use in thermal structure. The results of the tests showed composites with superior mechanical properties when compared with the conventional phenolic resin.
石墨/酚醛树脂复合材料双极板的制备与性能
Preparation and properties of graphite/phenolic resin composite bipolar plate
 [PDF]

陈惠,刘洪波,夏笑虹,杨丽,何月德
- , 2015, DOI: 10.13801/j.cnki.fhclxb.201503.008
Abstract: 双极板是质子交换膜燃料电池的重要组成部分, 石墨与聚合物的复合材料双极板是目前研究的重要方向。采用模压热固化二步法, 以酚醛树脂为粘结剂、天然鳞片石墨为导电骨料、炭黑为添加剂制备了质子交换膜燃料电池用复合材料双极板。系统研究了不同种类石墨对石墨/酚醛树脂复合材料电性能和抗弯强度的影响。结果表明: 以天然鳞片石墨为导电原料时, 所制备的石墨/酚醛树脂双极板的性能最好; 添加导电炭黑能有效提高石墨/酚醛树脂复合材料的电导率; 在复合材料制备中加入4wt%的碳纤维, 碳纤维-石墨/酚醛树脂复合材料的抗弯强度提高了29%; 碳纤维表面液相氧化处理能有效提高纤维与基体间的结合强度, 随着处理时间的延长与处理温度的升高, 碳纤维-石墨/酚醛树脂复合材料的电导率和抗弯强度都有很大程度的提高; 最终固化温度主要影响酚醛树脂的交联程度, 随着最终固化温度的升高, 酚醛树脂的交联程度增加, 电导率增大, 但抗弯强度有一定程度减小。 Bipolar plate is an important part of proton exchange membrane fuel cell. The composite bipolar plate of graphite and polymer is the main direction of research. With phenolic resin as binder, natural flake graphite as conductive aggregate, carbon black as additive, the composite bipolar plate for proton exchange membrane fuel cell was prepared by using the molding and thermosetting two-step method. The effects of graphite species on conductive properties and flexural strength of graphite/phenolic resin composites were investigated and analyzed systematically. The results show that there will be the best performance when the natural flake graphite is used as conductive raw material. The electrical conductivity of the graphite/phenolic resin composites can be effectively improved if conductive carbon black is added. By adding 4wt% carbon fiber into composites, the flexural strength of the carbon fiber-graphite/phenolic resin composites is improved by 29%. The liquid phase oxidation processing of carbon fiber surface can effectively improve the bonding strength between the fibers and matrix. With the extending of processing time and elevating of processing temperature, electrical conductivity and flexural strength of carbon fiber-graphite/phenolic resin composites are greatly improved. The final curing temperature mainly affects the cross-linking degree of phenolic resins. With the increase of final curing temperature, the crosslinking degree of phenolic resin gets increased, and the electrical conductivity increases while flexural strength decreases to a certain extent. 湖南省科技重大专项(2013FJ1001-2);高校青年教师成长计划(531107040186)
Preparation of Cefradine÷Montmorillonite Intercalation Compound
ZHAO Yan-Zhao, GUO Wen-Ji, WANG Lan
无机材料学报 , 2012, DOI: 10.3724/sp.j.1077.2012.00655
Abstract: The cefradine/montmorillonite compounds were prepared by pharmaceutical montmorillonite (MMT) and sodium―montmorillonite (Na―MMT) by the method of solution intercalation. The drug load was quantitatively measured by UV spectrophotometry. The structures of compounds were determined by X―Ray Diffraction (XRD) and Fourier transformed infrared (FT―IR) spectroscope. The results show that cefradine can be intercalated into MMT mainly due to ion exchange, which cannot intercalate into MMT by mechanically mixing. Pharmaceutical MMT shows better ion exchange property after sodium modification, which is easily intercalated. The basal spacing of pharmaceutical MMT changes little after intercalation in water, however, the basal spacing of Na―MMT and pharmaceutical MMT after sodium modification increase.
Study of Factors Affecting the Ablation Rate of Phenolic Resin/Fiber Glass
Nattawat Winya,Adulyasak Boonpan,Komson Prapunkarn
International Journal of Chemical Engineering and Applications , 2013, DOI: 10.7763/ijcea.2013.v4.302
Abstract: In this study, design experimental by two-level Factorial design to screen the factors to those factors that affect the ablation rate significantly. The following parameters were varied: amount of phenolic curing temperature and curing time. Factors that affect the ablation rate are as follows curing time, amount of phenolic resin, interaction between curing temperature and curing time, interaction between curing time and amount of phenolic resin, interaction between curing temperature and amount of phenolic resin and 3-way interaction of amount of phenolic resin, curing temperature and curing time. As the results of main effects analysis to determine 0.75 wt.% of phenolic resin, curing temperature 160 °C and curing time 35 min to give the ablation rate was 0.121 mm/s less than 0.14 mm/s according MIL-l-24768 standard.
Preparation of porous carbon particle with shell/core structure
eXPRESS Polymer Letters , 2007, DOI: 10.3144/expresspolymlett.2007.42
Abstract: Porous carbon particles with a shell/core structure have been prepared successfully by controlled precipitation of the polymer from droplets of oil-in-water emulsion, followed by curing and carbonization. The droplets of the oil phase are composed of phenolic resin (PFR), a good solvent (ethyl acetate) and porogen (Poly(methyl methacrylate), PMMA). The microstructure was characterized in detail by scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption, and thermo gravimetric analysis (TGA). The obtained carbon particles have a capsular structure with a microporous carbon shell and a mesoporous carbon core. The BET surface area and porous volume are calculated to be 499 m2g-1 and 0.56 cm3g-1, respectively. The effects of the amount of porogen (PMMA), co-solvent (acetone) and surfactant on the resultant structure were studied in detail.
Preparation and Characterization of Guar-Montmorillonite Nanocomposites  [PDF]
Rola Mansa,Christian Detellier
Materials , 2013, DOI: 10.3390/ma6115199
Abstract: Polymer-clay nanocomposites are highly sought-after materials, mainly due to their applicability in a variety of avenues. From the standpoint of the preparation of these nanocomposites, however, organic compatibility with clay and adherence to “green chemistry” concepts and principles can be limiting factors. As such, the objective was to prepare a biopolymer-modified clay nanocomposite using a simple and environmentally friendly method of preparation, whereby pre-treatment of the clay for organic compatibility was bypassed. Novel montmorillonite nanocomposites were prepared using neutral guar gum and cationic guar gum. X-ray diffraction (XRD) and transmission electron microscopy (TEM) confirmed the formation of intercalated structures. A monolayer configuration of cationic guar within the interlayer space was indicated by XRD results, while treatment with neutral guar gum resulted in the observance of both monolayer and bilayer configurations. Additionally, TEM results indicated partial exfoliation. Results attributed from 13C cross polarization/magic angle spinning nuclear magnetic resonance spectroscopy (CP/MAS NMR) of the nanocomposites indicated peaks corresponding to the guar constituent, confirming the adsorption of the biopolymer. Inductively coupled plasma emission spectrometry (ICP-ES) results indicated the exchange of cations present in neutral guar gum with the sodium cations of montmorillonite, in the case of the neutral guar nanocomposites.
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