微波辐射在高分子材料降解中的应用

综述了微波在天然高分子材料和合成高分子材料降解反应中的应用研究情况,分析了微波辐射对高分子材料降解反应特点,并指出了微波在高分子降解的实际应用中所面临的问题.     

改性淀粉类衍生物絮凝剂的研究及其应用进展

高分子絮凝剂的研究、生产和应用在近几年迅速发展,相对于无机高分子及有机高分子絮凝剂,改性的天然高分子絮凝剂具有无毒、环保、原料丰富易得等优点在工业废水及生活污水处理中得到广泛得应用,本文介绍了近几年国内在利用淀粉改性制备新型的多功能絮凝剂的研究情况和应用现状。     

复合抗菌高分子材料的研究现状及应用前景

综述了近几年国内外复合抗菌高分子材料的主要类型、研究现状、应用领域,指出了单一抗菌剂在高分子材料应用领域的缺点,说明了现阶段复合抗菌高分子应用研究的主要进展,在此基础上对复合抗菌剂的研究及应用前景进行了展望。     

POLYFLOW在高分子成型加工中的应用研究进展

在聚合物制品外形控制和性能调控过程中,高分子熔体的流动分析对于研究高分子成型工艺至关重要.POLYFLOW软件在高分子成型加工中的应用日渐广泛.本文深入分析了POLYFLOW在挤出、吹塑和热成型等方面的应用,重点介绍了挤出过程中的正向流动仿真和逆向口模设计,最后对POLYFLOW在高分子成型加工中的应用研究方向进行展望...     

阻燃高分子材料的开发及其应用研究进展

在介绍阻燃高分子材料开发的基础上,对阻燃高分子制备的研究情况进行了综述,包括分子内杂化阻燃高分子、添加机型阻燃高分子等,同时总结了阻燃高分子的应用范围,并展望了其未来的研究方向。     

我国高分子化工材料的发展现状

随着科学技术的发展,我国高分子材料得到了飞速的发展,其在各个领域都有着应用。主要分析了我国高分子材料的发展状况,之后研究了高分子材料在不同领域的应用。     

煤矸石制无机高分子絮凝剂进展

煤矸石在无机高分子絮凝剂制备方面正逐步得到应用,近年来的研究重点主要集中在复合型无机高分子絮凝剂方面。重点介绍了煤矸石基无机高分子絮凝剂的制备方法及在水处理中的应用,并展望了发展前景。指出煤矸石制无机高分子絮凝剂技术已经取得很大的发展,但与大规模工业化仍存在差距,要加大对煤矸石基无机高分子絮凝剂的基础和应用研究,改善生产工艺,提高产品质量,从而带动相关产业的发展。     

功能高分子材料的性能及应用

功能高分子材料具有独特的功能和不可替代的特性,其应用可促进各领域技术进步。通过对目前国内国外功能高分子材料研究现状进行分析,将功能高分子材料与传统材料进行比较,阐述功能高分子材料的性能及应用。对功能高分子材料的现状、性能及应用趋势进行全面的、系统的研究,对功能高分子材料的应用前景进行展望与分析。     

高分子聚合物在洗涤剂中的应用

从高分子聚合物的特点出发 ,综述了不同分子结构、不同分子量的高分子聚合物在洗涤剂中各个方面的应用。这些应用方面包括 :高分子表面活性剂 ;高分子对洗涤剂在制造和使用中的流变行为改性 ;高分子在洗涤过程中的抗再沉积作用、防色转移作用和对织物纤维的抗污处理作用(又称污垢释放剂作用)。最后 ,就高分子在洗涤剂中应用研究的现状及趋势作了简要概述。     

改性淀粉的制备及其在水处理中的应用

淀粉是一种来源广泛的天然高分子,近几年,对改性淀粉絮凝剂的研究、生产和应用发展迅速,相对于无机高分子及有机高分子絮凝剂,改性的天然高分子絮凝剂具有无毒、环保、原材料丰富易得等优点,在工业废水及生活污水处理中得到广泛的应用,本文介绍了近几年国内外在利用淀粉改性制备各种新型的多功能絮凝剂的研究情况和应用现状。     

Nanoscale Indentation of Polymer Systems Using the Atomic Force Microscope

The use of the atomic force microscope (AFM) to measure surface forces has been developed to optimize its operation as a surface imaging tool. This capability can potentially be extended to evaluate nanoscale material response to indentation and would be ideal for the evaluation of multi-component polymer systems, such as adhesives and composites. In this paper, previous work related to the development of the AFM as a nanoindentation device is reviewed, and a technique is proposed which allows the AFM to be used to probe local stiffness changes in polymer systems. Cantilever probes with spring constants ranging from 0.4-150 N m were used to investigate a number of polymer systems, including an elastomer, several polyurethane systems, thermally cured epoxies, a thermoplastic polymer-thermosetting polymer adhesive system, and a thermoplastic matrix composite.     

Improved Sensitivity in the Thermal Investigation of Polymeric Nanophases by Measuring the Resonance Frequency Shift using an Atomic Force Microscope

A novel technique has been developed to measure thermal transitions of polymers with the atomic force microscope (AFM) in the non‐contact mode. The resonance frequency of the AFM cantilever is measured as a function of the temperature, and thermal transitions of a polymer are clearly visible as changes in the resonance frequency/temperature response curve. Using the AFM in this mode allows the determination of the thermal properties of a material at a specific spot on the sample, on a macromolecular scale. This adds a new dimension to the standard thermal analysis techniques, rendering it possible to resolve the individual thermal transitions of different polymer phases, for example in structured multiphase polymers.     

Preparation and tribological properties of polymer film covalently bonded to silicon substrate via an epoxy-terminated self-assembled monolayer

A covalently immobilized polymer film was constructed on silicon substrate by a two-step method. As an anchor interlayer, (3-glycidoxypropyl)trimethoxysilane (GPMS) was self-assembled on hydroxylated silicon substrate to create epoxy-terminated surface, then poly(styrene-b-acrylic acid) (PSAA) was chemically grafted to the epoxy-derivatized substrates. The formation and surface properties of the films were characterized by means of ellipsometry, water contact angle measurement, attenuated total reflectance Fourier transform infrared spectrometry, X-ray photoelectron spectroscopy, and atomic force microscope (AFM). The nano- and micro-tribological properties of the films were evaluated by AFM and ball-on-plate tribometer, respectively. The results show that GPMS–PSAA film exhibits excellent durability and wear resistance, which is attributed to the molecular components of PSAA and the firm bonding between polymer molecules and silicon substrate via epoxysilane molecular glue. The influence of interlayer between polymer and substrate surface on tribological properties of ultrathin polymer film was revealed, which has an important significance upon designing ultrathin lubrication films with excellent tribological properties for micro/nanoelectromechanical systems.     

Characterization of Poly (Methyl Acrylate) Grafted Bleached Sulfite Pulp Fibers using AFM,AEM, EDS and STEM

Abstract

Sulfite pulp fibers were grafted by poly (methyl acrylate) at a low‐consistency (1% pulp consistency) and medium‐consistency (10% pulp consistency). It is of fundamental interest to determine the distribution of the polymer chains obtained at different fiber concentrations during grafting. In this study, modern analytical tools such as atomic force microscope (AFM), energy dispersive spectrometer (EDS), and scanning transmission electron microscope (STEM) were used for investigating the distribution of the polymer chains in the fiber matrix. AFM images in tapping mode showed that the fiber surface was covered with in‐situ generated polymers. The X‐ray mapping of Na in the cross‐section of the hydrolyzed grafted fibers by using EDS in combination with Na line scans by STEM showed that the distribution of poly (methyl acrylate) was affected by the pulp consistency during grafting; at a medium‐consistency condition the outer region of the fiber structure had a higher polymer concentration than the inner region. On the other hand, at a low‐consistency condition, grafting occurred uniformly across the fiber wall structure.     

Controlled nanodot fabrication by rippling polycarbonate surface using an AFM diamond tip

The single scratching test of polymer polycarbonate (PC) sample surface using an atomic force microscope (AFM) diamond tip for fabricating ripple patterns has been studied with the focus on the evaluation of the effect of the tip scratching angle on the pattern formation. The experimental results indicated that the different oriented ripples can be easily machined by controlling the scratching angles of the AFM. And, the effects of the normal load and the feed on the ripples formation and their periods were also studied. Based on the ripple pattern formation, we firstly proposed a two-step scratching method to fabricate controllable and oriented complex three-dimensional (3D) nanodot arrays. These typical ripple formations can be described via a stick-slip and crack formation process.     

Study on the morphology of the novel hydrophobically associative acrylamide‐based terpolymer in aqueous solution by AFM measurements

The synthesized hydrophobically associating water‐soluble polymer P(AM‐BST‐NaAMPS) (PASA) exhibits good viscosification properties in the aqueous and brine solution. To study the viscosifying mechanisms of the polymer in the aqueous solution and brine solution, atomic force microscope (AFM) was applied to observe the micromorphology of the polymer solution. The AFM measurements show that continuous network structures have been formed in the aqueous solution of 0.05 g dL^?1 PASA, and with the increase in PASA concentration, the network structures become much bigger and more condensed. The network structures of PASA are collapsed by the addition of salt, and tree‐like crystals are formed, leading to the decrease in the apparent viscosity of PASA solution. However, by increasing the NaCl concentration or the polymer concentration in the brine solution, the sizes of crystals increase. These results are consistent with the ESEM and viscosity study results. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3996–4002, 2006     

How atomic force microscopy has contributed to our understanding of polymer crystallization

Over the past two decades atomic force microscopy (AFM) has become one of the most frequently used tools for studying polymer crystallization. The combination of high resolution, minimal sample preparation and the ability to image non-destructively has allowed visualisation of crystallization, melting and re-ordering processes at a lamellar and sub-lamellar scale, revealing complexities that could only previously be guessed at. Here the insights that AFM has provided into some of the main over-arching questions relating to polymer crystallization are reviewed. The emphasis is on the use of AFM to image growth in real time, and on contributions that have been made to our understanding of polymer crystallization in general, rather than to specific systems.     

油水乳状液的稳定机理及其化学破乳技术的研究进展

油/水乳状液的破乳是重油生产和加工过程的重要环节,破乳剂的研发一直是油田化学中重要的研究内容。本文综述了国内外化学破乳剂研发的现状与趋势,阐述了重油中以沥青质为主的天然乳化剂的结构特点,深入分析了沥青质在油水乳状液的形成与稳定的过程中所起到的关键性作用,揭示了油水乳状液的形成与稳定性机理。进一步论述了具有普适性强、无毒、可生物降解且价格低廉的天然高分子破乳剂的破乳作用及其最新研究结果。重点介绍了微吸液管技术和原子力显微镜技术等现代分析手段在油水乳状液破乳过程中对相关微观机理研究的重要应用。     

Investigation of gravity‐spun,melt‐spun,and melt‐blown polypropylene fibers using atomic force microscopy

The morphology exhibited in a polymer depends on the particular process and processing conditions used to shape and modify the polymer. This morphology has an important influence on the final polymer product (sheet, molded part, etc.). Ten years ago, atomic force microscopy (AFM) was applied for the first time on polymer materials. Since then, AFM has been used extensively on polypropylene (PP) surfaces, but still very little has been reported on the use of AFM for analyzing PP fibers. The purpose of our work was to show the modifications of (a) the morphology and (b) the microstiffness of PP fiber surfaces processed under different operating conditions. Three fiber production processes were used: gravity spinning, melt spinning, and melt blowing. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1921–1937, 2000     

Elasto-plastic and visco-elastic deformations of a polymer sphere measured using colloid probe and scanning electron microscopy

The adhesive interaction energy between a single 27 μm polystyrene sphere and a flat silica surface has been measured, as a function of applied load on the sphere, using an atomic force microscope (AFM). The pull-off force required to remove the sphere from the surface after application of a given load was found to increase as a function of the applied load. These data are indicative of a plastic or elasto-plastic deformation of the sphere. Simple analyses of these data using established elastic/plastic deformation theories indicate that, at the loads used, the system is most probably undergoing an elasto-plastic deformation. Further evidence for some plastic deformation of the sphere was obtained using scanning electron micrographs of the same sphere after an AFM experiment had been completed. Careful analysis of all these data indicated a significant time dependence of these adhesive interactions due to the viscoelastic nature of the polymer bead in question.