新型铸造用淀粉/膨润土复合粘结剂的红外研究

以木薯淀粉为主要原料,自行研制的有机膨润土为改性剂,经过熔融和溶液插层等工艺制备木薯淀粉/膨润土复合粘结剂。采用FTIR和XRD手段表征及力学性能测试。结果表明,PVA插层改性后的有机膨润土的层间距大于有机膨润土的层间距大于Na基膨润土的层间距,膨润土的层间距越大,越有利于淀粉与膨润土的插层反应,得到的复合粘结剂的干强度也越高。该复合粘结剂具有粘结强度高、 抗吸潮性好,且成本低、 工艺简单和环境友好。     

ZrO2薄膜的改性与抗激光损伤研究

采用水热合成技术,制备了ZrO2胶体,用旋涂法镀制了单层ZrO2介质膜以及添加了有机粘合剂PVP的复合ZrO2-PVP薄膜。采用X射线衍射(XRD)、椭偏仪、红外分光光度计（FTIR）、原子力显微镜（AFM）等仪器对干凝胶及薄膜进行了性能测试和表征,并用输出波长为1.064 μm、脉宽为10 ns的电光调Q激光系统产生的强激光测试其激光损伤阈值。测得ZrO2和ZrO2-PVP薄膜在300 ℃热处理60 min后的激光损伤阈值分别为24.5 J/cm2和37.8 J/cm2。研究表明：添加有机粘合剂后的复合薄膜具有平整的表面结构;有机粘合剂的添加有助于提高薄膜的折射率和激光损伤阈值,其中,ZrO2-PVP 复合薄膜的折射率可高达1.75,激光损伤阈值达到37.8 J/cm2,比ZrO2单层膜的激光损伤阈值提高50%。     

SYNTHESIS OF STYRENIC TONER PARTICLES BY SPG EMULSIFICATION TECHNIQUE

This research studied the initiator efficiency for producing polymeric particles of poly(styrene-co-methylmethacrylate) copolymers by a Shirasu porous glass membrane (SPG) emulsification technique followed by suspensioncopolymerization. BPO, ADVN, and AIBN were used as initiators and we found that BPO is the most suitable initiator.Copolymers for various feed ratios of styrene/methyl methacrylate were thus synthesized by benzoyl peroxide, and theircopolymer particle size, molecular weight distribution and particle size distribution were characterized. Then n-BMA or 2-EHMA was added as the third monomer to decrease the terpolymer glass transition temperature. This article describes thepreparation technique, recipes and polymerization conditions for producing both copolymer and terpolymer panicles, particlesize changes, the corresponding particle morphologies and glass transition temperatures.     

Molecular Dynamics Simulations for Effects of Fluoropolymer Binder Content in CL-20/TNT Based Polymer-Bonded Explosives

In order to better understand the role of binder content, molecular dynamics (MD) simulations were performed to study the interfacial interactions, sensitivity and mechanical properties of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane/2,4,6-trinitrotoluene (CL-20/TNT) based polymer-bonded explosives (PBXs) with fluorine rubber F₂₃₁₁. The binding energy between CL-20/TNT co-crystal (1 0 0) surface and F₂₃₁₁, pair correlation function, the maximum bond length of the N–NO₂ trigger bond, and the mechanical properties of the PBXs were reported. From the calculated binding energy, it was found that binding energy increases with increasing F₂₃₁₁ content. Additionally, according to the results of pair correlation function, it turns out that H–O hydrogen bonds and H–F hydrogen bonds exist between F₂₃₁₁ molecules and the molecules in CL-20/TNT. The length of trigger bond in CL-20/TNT were adopted as theoretical criterion of sensitivity. The maximum bond length of the N–NO₂ trigger bond decreased very significantly when the F₂₃₁₁ content increased from 0 to 9.2%. This indicated increasing F₂₃₁₁ content can reduce sensitivity and improve thermal stability. However, the maximum bond length of the N–NO₂ trigger bond remained essentially unchanged when the F₂₃₁₁ content was further increased. Additionally, the calculated mechanical data indicated that with the increase in F₂₃₁₁ content, the rigidity of CL-20/TNT based PBXs was decrease, the toughness was improved.     

ZrO2/ SiO2多层膜的化学法制备研究

分别以ZrOCl2·8H2O 和正硅酸乙酯为原料,采用溶胶-凝胶工艺制备了性能稳定的ZrO2和SiO2溶胶。用旋转镀膜法分别在K9玻璃和单晶硅片上制备了ZrO2/ SiO2多层膜。采用溶剂替换和紫外光处理等手段,有效地解决了ZrO2/SiO2多层膜中膜层开裂和膜间渗透等问题。应用扫描电子显微镜观测了薄膜的表面和剖面微观形貌,并用椭偏仪测得薄膜的厚度和折射率,研究了薄膜厚度、折射率与热处理温度、紫外光处理时间的关系,对所获得薄膜的紫外-可见、红外光谱进行了分析。用输出波长1064nm ,脉宽15ns 的电光调Q光系统产生的强激光进行了单层膜的辐照实验,结果发现溶剂替换后激光损伤阈值有所提高。     

Application of Guar Gum and its Derivatives as Green Binder/Separator for Advanced Lithium-Ion Batteries

Since their first commercialization in the 1990s,lithium-ion batteries (LIBs) have become an indispensible part of our everyday life in particular for portable electronic devices. LIBs have been considered as the most promising sustainable high energy density storage device. In recent years, there is a strong demand of LIBs for hybrid electric and electric vehicles to lower carbon footprint and mitigate climate change. However, LIBs have several issues, for example, high cost and safety issues such as over discharge, intolerance to overcharge, high temperature operation etc. To address these issues several new types of electrodes are being studied. Traditional binder PVDF is costly, difficult to recyle, undergoes side reactions at high temperature and cannot stabilize high energy density electrodes. To overcome these challenges, diiferent binders have been introduced with these electrodes. This minireview is focused on the application of guar gum as a binder for different electrodes and separator. The electrochemical performance of electrodes with guar gum has been compared with other binders.     

煤沥青橡胶改质筑路油老化过程中族组成与性质变化

实验室与户外跟踪老化研究发现 ,道路沥青在使用过程中的质量蜕变主要是由于氧化作用[1,2 ]使得道路沥青中沥青质含量增加 ,改变了沥青中分散相与连续相的比例 ,致使沥青的性质发生变化 ,如软化点升高、针入度降低以及粘度增加等[3,4]。上述研究所取得的成果主要是以石油为原料的道路沥青 ,对以煤沥青为原料开发的改质筑路油研究较少。本文在成功开发煤沥青改质筑路油工艺的基础上 ,研究了改质筑路油热老化过程中族组成与性质的变化 ,由此提出煤沥青改质筑路油高温热老化过程中性质变化的主要原因。1　实验部分1 1　原料　试验所用原料为实…     

Surface microstructure of bitumen characterized by atomic force microscopy

Bitumen, also called asphalt binder, plays important roles in many industrial applications. It is used as the primary binding agent in asphalt concrete, as a key component in damping systems such as rubber, and as an indispensable additive in paint and ink. Consisting of a large number of hydrocarbons of different sizes and polarities, together with heteroatoms and traces of metals, bitumen displays rich surface microstructures that affect its rheological properties. This paper reviews the current understanding of bitumen's surface microstructures characterized by Atomic Force Microscopy (AFM). Microstructures of bitumen develop to different forms depending on crude oil source, thermal history, and sample preparation method. While some bitumens display surface microstructures with fine domains, flake-like domains, and dendrite structuring, ‘bee-structures’ with wavy patterns several micrometers in diameter and tens of nanometers in height are commonly seen in other binders. Controversy exists regarding the chemical origin of the ‘bee-structures’, which has been related to the asphaltene fraction, the metal content, or the crystallizing waxes in bitumen. The rich chemistry of bitumen can result in complicated intermolecular associations such as coprecipitation of wax and metalloporphyrins in asphaltenes. Therefore, it is the molecular interactions among the different chemical components in bitumen, rather than a single chemical fraction, that are responsible for the evolution of bitumen's diverse microstructures, including the ‘bee-structures’. Mechanisms such as curvature elasticity and surface wrinkling that explain the rippled structures observed in polymer crystals might be responsible for the formation of ‘bee-structures’ in bitumen. Despite the progress made on morphological characterization of bitumen using AFM, the fundamental question whether the microstructures observed on bitumen surfaces represent its bulk structure remains to be addressed. In addition, critical technical challenges associated with AFM characterization of bitumen surface structures are discussed, with possible solutions recommended. For future work, combining AFM with other chemical analysis tools that can generate comparable high resolution to AFM would provide an avenue to linking bitumen's chemistry to its microscopic morphological and mechanical properties and consequently benefit the efforts of developing structure-related models for bituminous materials across the different length scales.     

Developments in the production of biological and synthetic binders for immunoassay and sensor-based detection of small molecules

The need for chemical and biological entities of predetermined selectivity and affinity towards target analytes is greater than ever, in applications such as environmental monitoring, bioterrorism detection and analysis of natural toxin contaminants in the food chain.In this review, we focus on advances in the production of specific binders, in terms of both natural entities (e.g., antibodies) and synthetic binders (e.g., molecularly-imprinted polymers). We discuss the potential of emerging technologies for integration into immunoassay and sensing techniques. We place special emphasis on use of these technologies in bioanalytical applications.     

Effect of high adhesive polyvinyl alcohol binder on the anodes of lithium ion batteries

High molecular weight (MW) polyvinyl alcohol (PVA) was synthesized by two-step polymerizations and employed as an anodic binder of lithium ion batteries (LIBs). Numerous hydroxyl groups in PVA formed strong hydrogen bonds with both active materials and the current collector. These strong hydrogen bonds led to an increase in the amount of binder covering the surface of active materials and significantly enhanced the adhesion strength of electrodes. The high MW PVA binder showed much better cyclic performance for silicon/carbon anodes than polyvinylidene fluoride (PVDF) and polyacrylic acid (PAA) binders.