Preparation and characterization of chitosan/KSF biocomposite film

Chitosan–clay biocomposites have been prepared in which KSF‐montmorillonite (KSF) is used as filler and diluted acetic acid is used as solvent for dissolving and dispersing chitosan and montmorillonite, respectively. The effect of KSF loadings in biocomposites has been investigated. The characterization with different methods (FTIR, DSC, TGA, SEM, and XRD) on chitosan/KSF biocomposites systems was examined. Morphology and properties of chitosan biocomposites have been studied compared with those of pure chitosan. The FTIR and SEM results indicated the formation of an intercalated‐and‐exfoliated structure at low KSF content and an intercalated‐and‐flocculated structure at high KSF content. The thermal stability and the mechanical properties of the composites were also examined by DSC, TGA/DTG, and tensile strength measurements, respectively. The dispersed clay improves the thermal stability of the matrix systematically with the increase of clay loading. Tensile strength of a chitosan film was enhanced until the clay ratio up to 2 wt% and elongation‐at break decreased with addition of clay into the chitosan matrix. The XRD results confirmed the intercalation of the biopolymer in the clay interlayer by the decrease of 2θ values while the chitosan–clayratio increases. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers     

Preparation and characterization of sulfated titanium-modified pillared montmorillonite

Sulfated titanium-modified pillared montmorillonites using (NH₄)₂SO₄ and H₂SO₄ have been prepared. The influence of the method of sulfation and of the SO₄ ²/Ti mole ratio was studied. An important effect in both the basal spacings and the acidic properties was observed when (NH₄)₂SO₄ or H₂SO₄ is present in the solution of intercalation. When titanium pillared clays (Ti-PILCs) are sulfated by impregnation, their acidity initially increases, irrespective of the sulfate source, whereas their basal spacings are not modified. A loss of specific surface area is observed when the temperature of calcination or the SO₄ ^2-/Ti mole ratio is increased. This revised version was published online in July 2006 with corrections to the Cover Date.     

Al - Cu柱撑蒙脱土的超声制备与表征

以钠基蒙脱土为原料,在超声波作用下制备Al-Cu柱撑蒙脱土。柱撑溶液中的n(OH-)∶n(Al3 )为2.4,n(Cu)∶n(Al3 )为1∶9,可得到层间距d(001)值为1.9553 nm,比表面积为183.6m2.g-1的产物。采用X射线衍射分析(XRD)、红外光谱(FTIR)、透射电镜(TEM)、扫描电镜(SEM)和差示扫描量热(TG-DSC)等手段对制备的柱撑蒙脱土进行了表征,结果表明:钠基蒙脱土经反应后,柱撑剂进入到蒙脱土层间,与蒙脱石骨架发生成键反应形成Si-O-Cu或Si-O-Al键,使得蒙脱土的层间距和比表面积都显著的增大,热稳定性也显著地提高了。     

Preparation and characterization of layered carbon hybrid framework materials pillared with titanocene

Novel graphene oxide layered hybrid framework materials pillared titanocene organometallic complex were prepared through a facile ultrasound intercalation approach. The products exhibited periodic layered structures with expanded interlayer spacing as characterized by XRD. Raman spectroscopy demonstrated that the skeleton structure of layered carbon still remained after titanocene treatment. Nitrogen sorption analysis indicated that the building blocks of graphene oxide sheets were cross-linked with titanocene molecules to form lamellar porous structures.     

Preparation and characterization of pillared carbons obtained by pyrolysis of silylated graphite oxides

Pillared carbons were prepared by pyrolyzing various graphite oxides silylated by 3-aminopropylmethyldiethoxysilane. They were formed when silylated graphite oxides with silicon contents of 12.6% or higher were pyrolyzed in vacuo at 500-600 °C. Their interlayer spacings were 1.23-1.31 nm. When silylated graphite oxide was prepared at 90 °C, the reductive decomposition of graphite oxide by amino groups of 3-aminopropylmethyldiethoxysilane was suppressed and pillared carbon with higher crystallinity was obtained. At higher temperatures of pyrolysis, silylated graphite oxide decomposed to residual carbon without pillars. The pillars between the carbon layers contained methyl groups originating from the 3-aminopropylmethyldiethoxysilane. Based on the interlayer spacing and elemental analysis data, a structure model for the pillar is proposed. Pillared carbons showed type IV nitrogen adsorption isotherms and they contained both mesopores and a small volume of micropores. The BET surface area of the pillared carbon reached a maximum value of 236 m²/g, when it was prepared from graphite oxide silylated at 105 °C for 20 days.     

Preparation and characterization of poly(acrylic acid)/pillared clay superabsorbent composite

Pillared clay-based superabsorbents (PILC-SA) were synthesized by using Al pillared-montmorillonite K10 and KSF via graft copolymerization reaction of acrylic acid (AA). Swelling behavior of pillared clay-based superabsorbent films in distilled water and at different pH values were investigated at room temperature. It was also obtained that Al-KSF and Al-K10 based superabsorbents were pH dependent and showed a reversible swelling behavior. Water absorbency of Al-KSF based superabsorbent was higher than that of Al-K10 based one. SEM, FTIR, and XRD analysis were conducted for further characterization of the PILC-SA. FTIR analyses lead to ester formation between PILC and SA. XRD revealed the basal spacing of the pillared clays before and after in situ incorporation indicating that the morphology of the superabsorbent was exfoliated and the layers of clay dispersed on the composite.     

Sb4O5Cl2柱撑蒙脱土复合阻燃剂的制备及表征

以Sb4O5Cl2纳米粒子为柱化剂,采用酸溶法和醇盐水解法制备了Sb4O5Cl2柱撑蒙脱土复合阻燃剂,并用FI-IR、XRD和TEM对产品进行了表征.结果表明酸溶法要优于醇盐水解法,柱撑后蒙脱土的间距扩大,呈弱晶态,蒙脱土和Sb4O5Cl2纳米粒子结合完美,成本低廉,可作为一种有效的添加型阻燃剂.     

Preparation and characterization of chitosan/montmorillonite‐K10 nanocomposites films for food packaging applications

Chitosan (CS)/montmorillonite‐K10 (MMTK‐10) clay composite films with different amounts of the clay MMTK‐10 (0.5, 1, 2.5, and 5%) were prepared using a solution‐casting method, and their properties were determined. The objective of this study is to prepare CS/clay nanocomposites and then to investigate the effects of clay content on mechanical, barrier, and thermal properties of these nanocomposites. The prepared films were characterized by Fourier transform infrared spectroscopy, X‐ray diffraction analysis, transmission electron microscopy, and scanning electron microscopy. Barrier properties (oxygen and water permeability), mechanical properties (tensile strength and elongation), and thermal behaviors (thermogravimetric analysis) were investigated and compared. The water vapor and gas permeability values of the composite films decreased significantly with increasing filler concentration. Tensile strength of the composites increased significantly with the addition of clay, and elongation at break decreased with increasing clay concentration. The tensile strength of nanocomposites is up to 34.82 MPa for 5 wt% clay content, and the tensile modulus shows a 74.63% higher value than that of neat CS. The resulting films had an opaque appearance, which depended on the amount of MMTK‐10 added. The oxygen permeability decreased with the increase in MMTK‐10. The minimum oxygen permeability (1.54 cm³/m² day atm) was recorded for film with 5% MMTK‐10. The water permeability of the composite films decreased significantly between 13 and 22% when clay was added. The dispersed clay improves the thermal stability and enhances the hardness and elastic modulus of the matrix systematically with the increased loading of clay. POLYM. COMPOS., 33:1874–1882, 2012. © 2012 Society of Plastics Engineers     

马来酸酐酰化β-环糊精柱撑Zn/Al-CO_3型水滑石的制备及表征

通过酯化反应合成马来酸酐酰化β-环糊精(β-CD),采用成核/晶化隔离法制备了Zn/Al水滑石(LDHs),并以水滑石为前驱体,用返混法进行插层组装合成马来酸酐酰化β-CD柱撑Zn/Al水滑石,利用XRD、FTIR对其结构进行表征。结果表明,利用返混法进行插层组装,可以成功的将马来酸酐酰化β-CD阴离子插入Zn/Al水滑石层间,其层间距由原来的0.76 nm增大为3.43 nm。     

An efficient oxidative coupling of naphthols catalyzed by Fe impregnated pillared montmorillonite K10

Montmorillonite K10 was modified with pillaring solutions of Fe. The catalyst was activated at different temperatures. The resultant heterogeneous catalyst was used for coupling of 2-naphthol and derivatives under mild operating conditions. The activity of catalyst was compared with Fe pillared bentonite, Fe-exchanged montmorillonite K10 and bentonite catalysts. Amongst them, K10-FePLS120 showed better activity and selectivity. The catalyst can be recycled without loss of activity.     

Al-Zn柱撑膨润土的制备与表征

以钙基膨润土为原料,先对其钠化改性得到合适的钠基膨润土,制备铝柱柱撑膨润土,并首次制备了铝锌柱撑膨润土。运用X射线衍射分析（XRD）、X射线荧光光谱分析（XRF）、红外（IR）和差示扫描量热法（DSC）等手段对制备的柱撑膨润土进行了初步表征,结果表明：钠基膨润土经柱撑反应后,柱化剂进入到膨润土层间,热处理后在层间形成了比较稳定的复合氧化物柱子,与蒙脱石骨架发生成键反应,形成Si—O—Zn或Si—O—Al键,在600℃焙烧温度下,柱撑膨润土仍能保持层状。     

Preparation and characterization of molecularly imprinted silica particles for selective adsorption of naphthalene

A new kind of molecularly imprinted adsorbent for naphthalene was prepared by a covalent/noncovalent hybrid strategy. The monomer-template compound was prepared by the reaction of 3-(triethoxysilyl)propyl isocyanate with β-naphthol to form a thermally cleavable urethane bond. The silica gel was prepared by means of the gelation of monomer-template compound with tetraethoxysilane in ethanol using sol–gel technology. The removal of the template by the cleavage of urethane bond at elevated temperature resulted in the generation of recognition sites which could rebind naphthalene through noncovalent interaction. Binding experiments demonstrated that the imprinted silica particles showed a very fast uptake profile for naphthalene and displayed highly selective recognizing ability for naphthalene over benzene and other PAHs such as anthracene, phenanthrene, pyrene, fluoranthene and triphenylene.     

Preparation of encapsulated aluminum pigments by emulsion polymerization and their characterization

An emulsion polymerization-like process for the encapsulation of commercial aluminum pigments with polymer is discussed. A possible application target is the improvement of the performance of aluminum pigment in waterborne coatings. The effect of the treatment on the stability of the aluminum pigments in the presence of alkaline water was examined. Analytical investigations with SEM, TEM, STEM-EDX, XPS, and TOC were performed and revealed a kind of coagulation mechanism of polymer particles on the pigment surface. D-63784 Obernburg, Germany.     

铝合金表面耐久性超疏水防护膜的制备与表征

通过酸刻蚀-沸水浴处理构筑微纳米分级结构,进而通过喷涂含有磷酸铝胶黏剂(AP)和低表面能物质——全氟辛基三氯硅烷(PFOTS)的悬浮液增强结合力并降低表面能,从而在国产7B04铝合金表面制备了耐久性超疏水防护膜。利用场发射扫描电子显微镜(FESEM)、X射线光电子能谱仪(XPS)、傅里叶变换红外光谱仪(FTIR)、接触角测试仪(CA)、电化学阻抗谱(EIS)等技术以及多种环境模拟实验对样品进行了表征,结果显示,制备的防护膜表面水静态接触角(WCA)高达158.4°,滑动角(SA)为0°,呈现出超疏水和低黏附性;膜层电阻(Rc)约为101.55 kΩ·cm2,在NaCl腐蚀介质中的电荷转移电阻(Rt)增大了近2个数量级,表现出优异的防护性能;样品可以经受多种破坏,具有理想的机械耐久性、化学耐久性和环境耐久性。     

Preparation and characterization of durable superhydrophobic protective coatings on aluminum alloy

The durable superhydrophobic protective coatings on the 7B04 aluminum alloy surface was prepared by using acid etching and boiling water bath to construct micro-nano hierarchical structure, and then spraying suspension containing aluminum phosphate adhesive (AP) and perfluorooctyltrichlorosilane (PFOTS) to increase adhesion and reduce surface energy. The samples were characterized by field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), contact angle measurement (CA), electrochemical impedance spectroscopy(EIS) and a variety of the environmental simulation experiments. The results showed that the static water contact angle (WCA) of the surface is 158.4° and the slide angle (SA) is about 0°, suggesting superhydrophobicity and low adhesion to water. The coating resistance (R_c) was as high as 101.55 kΩ· cm² and the charge transfer resistance (R_t) in NaCl corrosion medium increased by nearly two orders of magnitude, showing excellent protective performance. The sample can withstand a variety of damages, with ideal mechanical durability, chemical durability and environmental durability.     

铝电解用常温固化TiB_2涂层的制备与表征

以TiB2、炭素粉末、呋喃树脂、碳纤维等为主要原料,制备了铝电解用常温固化TiB2涂层。采用DTG对涂层各组分进行了热降解分析。通过DTG-DDTA分析研究了涂层糊料的炭化过程,制定了涂层糊料的炭化升温制度。采用XRD对涂层进行了成分分析,并通过SEM观察了涂层断面的形貌。结果表明,炭化过程中呋喃树脂分为3个阶段变化,炭素粉末只有一个阶段变化。涂层表面主要为TiO2和C,内层组分为TiB2和C。涂层中无裂纹和气泡孔,各相之间粘接很好,组织结构致密。     

微电池-层柱累托石吸附处理电镀废水试验

介绍了一种电化学-层柱累托石吸附法处理含铬电镀废水的新工艺；并对其影响处理效果的因素进行了探讨。在1L含Cr(Ⅵ)41mg，pH为0．96的电镀废水中加入0．3g微电池反应物TX，进行电化学处理60min；然后用15g层柱累托石常温振荡吸附30min，出水中Cr(Ⅵ)质量浓度降至0．2mg／L以下，达到国标GB8978-1996一级排放标准要求。在此基础上，我们与湖北荆州罗场镀膜厂合作进行了日处理10-15t，铬质量浓度为13-60mg／L电镀废水的工业试验。近1a的运行结果表明：出水水质均达到国标一级排放标准，说明该工艺对处理电镀厂废水具有明显的效果，具有广泛的开发和应用前景。     

Determination of porosity in pillared clays by N2 adsorption isotherms

N₂ adsorption isotherms of various pillared montmorillonites (PILCs) were analyzed for evaluation of their porosities. The quantitative data of the total and micropore volumes were calculated using the B.J.H. method and the t-plot, respectively. The volume of mesopores is the difference between the total volume and the micropore volume. The linear branch above the P/P ₀ of 0.5 should be used for the calculations of the micropore volume and external surface area.The evaluation of the specific surface area (SA) of the PILCs and influences of the porosity on the calculations were discussed in detail. An upper limit of the monolayer capacity of a porous solid is proposed, based on the adsorption on a nonporous solid. Due to the space restriction in the fine slit-like pores of the PILCs, the specific surface areas calculated with the B.E.T. equation using the adsorption data in a relative pressure region ranging from 0.01 to 0.1 are more accurate.The mean micropore widths of the PILCs, derived from the data of the multi-point B.E.T. SA and micropore volume consist reasonably with the pore widths obtained by XRD diffraction.The step-like curves of the t-plot in low-pressure region and of the logarithmic plot reveal presence of pores of various sizes in the pillared clays. The micropore size distribution can be derived by a new method using the N₂ adsorption data.     

吸附制冷用复合吸附剂的制备

用静态法测定主要吸附材料和自制复合吸附剂对水的吸附量,用TG DTA法对主要吸附材料的热稳定性和自制吸附剂对水的脱附峰端温度进行分析。对吸附剂原料复合比例、焙烧温度和扩孔剂种类等制备条件进行了实验研究。结果表明:自制复合吸附剂比单一吸附材料对水有着更大的吸附能力;DTA分析的脱水的峰端温度明显低于单一吸附材料;采用较高的焙烧温度和分段焙烧方法,可明显改善复合吸附剂的吸附性能及强度;对于用不同的吸附材料复合的吸附剂,需加入不同的扩孔剂,方可增加孔容和孔径,改善其吸附性能;自制复合吸附剂对水的吸附量显著高于13x和硅胶等传统吸附剂。其中,M1 9906和M1 9907复合吸附剂对水的吸附量大约是13x和硅胶的2～3倍。