Ion irradiation of poly(methyl methacrylate) for precise control of electrical and optical properties

Ion irradiation with Xe+ has been utilized to produce electrical conductivity in PMMA, as measured using a four-point in-line probe. Incident ion beam energy and current density have been varied to investigate their effect on electrical conductivity and optical absorbance of the samples after irradiation. Results support the premise that selection of beam parameters that maximize the ratio of energy transfer-producing displacements to energy transfer-producing ionization maximizes the ratio of induced conductivity to induced absorbance in the irradiated samples. Conductivity versus ion dose has also been shown to be well estimated using a damage trial model. © 1994 John Wiley & Sons, Inc.     

Blends of poly(methyl methacrylate) (PMMA) with PMMA ionomers: Mechanical properties

Rigid–rigid blends made of ionomer and ionomer precursor polymer, based on poly(methyl methacrylate) (PMMA), have been investigated. Two series of blends have been prepared for studying mechanical properties. In one series, dynamic mechanical properties were determined over a wide range of temperatures. As the weight fraction of the ionomer was increased, there was a modest increase of modulus at ambient temperature and a very large increase in the rubbery modulus at elevated temperatures above the glass transition temperature of PMMA. In a second series of tests, tensile stress–strain measurements, made at an ambient temperature, were carried out over a wide range of blend compositions. For all blends tested, the mechanical properties exhibited a synergistic enhancement, i.e., average values of modulus, strength and fracture energy were all higher than expected based on the rule of mixtures. Measurements of fracture toughness also exhibited synergy, with a maximum value, higher than the value of either blend component, being attained in blends containing about 30 wt % of the PMMA ionomer. These results are interpreted in terms of a higher resistance to fracture of the more chain-entangled ionomer phase and good interfacial adhesion between the two components of the blend. © 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 1235–1245, 1998     

PMMA纳米球的制备及其银膜包覆技术

采用无皂乳液聚合法制备了单分散、直径为170 nm左右的聚甲基丙烯酸甲酯(PMMA)纳米球, 然后利用3-甲基丙烯酰氧基丙基三甲氧基硅烷(MATS)和3-巯丙基三甲氧基硅烷(MPTMS)对PMMA纳米球进行表面改性, 在其表面包覆一层均匀的巯基, 通过巯基与银离子之间的相互作用, 使银在PMMA纳米球表面成核长大, 从而合成PMMA/Ag纳米球壳粒子. 通过扫描电子显微镜、投射电子显微镜和紫外-可见吸收光谱测试技术对产物性能进行了表征, 研究结果表明, 制备的PMMA/Ag纳米球壳粒子的分散性好、包覆均匀.     

Impact of Charge Transfer Complex on the Dielectric Relaxation Processes in Poly(methyl methacrylate) Polymer

The impact of the charge transfer complex on the dielectric relaxation processes in free poly(methyl methacrylate) (PMMA) polymer sheets was investigated. The frequency dependence of dielectric properties was obtained over the frequency range 0.1 Hz–1 MHz at temperatures ranging between 303 K and 373 K for perylene dye and acceptors (picric acid (PA) and chloranilic acid (CLA)) in an in situ PMMA polymer. The TG/dTG technique was used to investigate the thermal degradation of the synthesized polymeric sheets. Additionally, the kinetic parameters have been assessed using the Coats–Redfern relation. The dielectric relaxation spectroscopy of the synthesized polymeric sheets was analyzed in terms of complex dielectric constant, dielectric loss, electrical modulus, electrical conductivity, and Cole–Cole impedance spectroscopy. α- and β-relaxation processes were detected and discussed. The σ(ω) dispersion curves of the synthesized polymeric sheets show two distinct regions with increasing frequency. The impedance data of the synthesized polymeric sheets can be represented by the equivalent circuit (parallel RC).     

Polymer blend/organoclay nanocomposite with poly(ethylene oxide) and poly(methyl methacrylate)

A series of polymer blend/organoclay nanocomposite at a fixed blending ratio was prepared using equal ratio of poly(ethylene oxide) (PEO) and poly(methyl methacrylate) (PMMA) via solvent casting method. With respect to nanoscale internal structure, we found that PMMA chains have better affinity with organoclay than PEO, based on the results from X-ray diffraction. Direct visualization via transmission electron microscopy (TEM) also supported the better affinity of PMMA with organoclay by indicating the existence of hybrid structures of mainly intercalated but with some exfoliated forms. The miscible nature of the blend and homogeneous dispersion state of layered silicate in the blend system were investigated via the microscopic fractured surface morphologies. From rheological measurements (storage and loss modulus), we discovered the role of the physical network structure between polymer and organoclay to be a main factor for the enhancement of elastic properties.     

以水作相分离造孔剂制备P(VDF-HFP)/PMMA聚合物电解质膜

介绍了一种以水代替常用的有机物质作为相分离造孔剂制备混合型聚合物电解质的新方法.所研究的混合型聚合物为聚(偏二氟乙烯-六氟丙烯)和聚甲基丙烯酸甲酯的混合物.扫描电镜SEM图表明这种混合型聚合物膜具有蜂窝状结构,有利于膜电导率的增加.利用FTIR,XRD和DSC等方法研究了混合型聚合物电解质中两种聚合物间的相互作用.用电化学交流阻抗方法测得在30℃下P(VDF-HFP)/PMMA摩尔比为1:1的混合型聚合物电解质的离子电导率为0.804×10^-3S/cm.对照其它方法,本方法具有制备容易、成本较低和有利于环境保护等优点.     

聚甲基丙烯酸甲酯微流控分析芯片的简易热压制作法

提出聚甲基丙烯酸甲酯(PMMA)微流控分析芯片的一种简易热压制作法,研究了镍基、单晶硅和玻璃3种阳模制备芯片及芯片的封合条件.采用扫描电镜(SEM)和电荷耦合检测器(CCD)对PMMA芯片的微通道及其横截面形貌进行了表征.SEM图和CCD图表明实现了热压封接.测定了PMMA芯片的伏安曲线和电渗流,其电渗流值与文献报道值基本一致.本法制作的PMMA芯片用于电泳分离Cy5荧光染料,峰高RSD为2.2%(n=11),理论塔板数7.4×10⁴m^-1.     

Ricinus communis agglutinin I functionalisation of poly(methyl methacrylate) (PMMA) as a substrate for microfluidic device

We report a functionalisation strategy which is able to generate Ricinus communis agglutinin I (RCA 120) modified PMMA microfluidic device for binding and culturing living cells. The functionalisation is achieved by standard amine-aldehyde (Schiff base) reaction through the cross-linker, glutaraldehyde. To prove the ability of the RCA 120 modified PMMA surface, the PC 12 cell line (rat pheochromocytoma cells) has been captured and cultured by the microfluidic device. In the presence of tunicamycin, the dose/time-dependence on decreasing of binding affinity of RCA 120 modified device with PC 12 cell is also observed. The experimental results demonstrate that the lectin-functionalized microfluidic device can be employed as efficient cell culturing platform, and has a great promise of being used as a powerful tool for monitoring the interaction of drug with living cell.     

Simple Detection of Pigment Red 53 as a Hazardous Substance in Cosmetic Preparation Using a Polymer Combination of Polystyrene (PS) and Polymethylmethacrylate (PMMA)

Pigment red 53 is a synthetic dye that has been banned in cosmetic products due to the possibility of causing blood disorders and spleen sarcoma. The indicator strip employs qualitative analysis methods that are simpler, easier, and quicker than an instrumental analysis. The indicator strip is made of a polymethylmethacrylate (PMMA) and polystyrene (PS) mixture using a reagent blending method with specific reagents of concentrated sulfuric acid (H₂SO₄), concentrated hydrochloric acid (HCl), or 10% sodium hydroxide (NaOH). Pigment red 53 detections with an indicator strip are based on the occurrence of a specific color change reaction between the reagent and pigment red 53 through sulfonation with concentrated H₂SO₄, neutralization with 10% NaOH, and reaction of pigment red 53’s azo group with concentrated HCl. PMMA was made with a concentration of 5% (w/t), and mixtures of PS:PMMA 1:2, 1:3, and 1:4 had solvent-to-specific reagent ratios of 60:40, 80:20, and 90:10. The best results were obtained for PMMA-H2SO4 (90:10), PMMA-HCl (80:20), and PMMA-NaOH (60:40), with the lowest detection limits equaling 20 ppm, 50 ppm, and 20 ppm, respectively. Meanwhile, the best PS:PMMA (1:4)-based indicator strips obtained were PS:PMMA-H₂SO₄ (90:10), PS:PMMA-HCl (80:20), and PS:PMMA-NaOH (60:40), with the lowest detection limits being 20 ppm, 10 ppm, and 20 ppm, respectively. All indicator strips are stable for at least 80 days. Indicator strips can be used as a simple and applicable method for detecting pigment red 53 in cosmetic products with a good performance.     

Poly(methyl methacrylate) composites with size‐selected silver nanoparticles fabricated using cluster beam technique

An embedment of metal nanoparticles of well‐defined sizes in thin polymer films is of significant interest for a number of practical applications, in particular, for preparing materials with tunable plasmonic properties. In this article, we present a fabrication route for metal–polymer composites based on cluster beam technique allowing the formation of monocrystalline size‐selected silver nanoparticles with a ±5–7% precision of diameter and controllable embedment into poly (methyl methacrylate). It is shown that the soft‐landed silver clusters preserve almost spherical shape with a slight tendency to flattening upon impact. By controlling the polymer hardness (from viscous to soft state) prior the cluster deposition and annealing conditions after the deposition the degree of immersion of the nanoparticles into polymer can be tuned, thus, making it possible to create composites with either particles partly or fully embedded into the film. Good size selection and rather homogeneous dispersion of nanoparticles in the thin polymer film lead to excellent plasmonic properties characterized by the narrow band and high quality factor of localized surface plasmon resonance. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1152–1159     

Effect of Nanoclay on the Phase Separation Behavior of Poly（methyl methacrylate）/Poly（vinyl acetate） Binary Polymer Blends

The effect of nanoclay on the phase-separation behavior of poly（methyl methacrylate）/poly（vinyl acetate）（PMMA/PVAc） blends has been mainly investigated by small-angle laser light scattering. It is found that the effect of clay on the thermodynamics and kinetics of phase-separation for PMMA/PVAc blends seems inconsistent. The kinetics phaseseparation rate decreases, while the thermodynamics parameters, cloud points Tc and delay time tD of isothermal phaseseparation also decrease, and the variation amplitude depends on the matrix composition. The affinity of clay to PMMA results in the composition difference between the border layer and the polymer matrix and further causes the concentration fluctuation at the early stage of phase separation to reduce Tc and tD. On the other hand, the decrease of phase-separation rate is caused by the mechanical barrier effect of clay on the macromolecular diffusion of blend matrix. Hence, such seemingly counterintuitive results on the thermodynamics and kinetics of phase-separation are attributed to different dominant factors.     

聚甲基丙烯酸甲酯微流控芯片分离DNA片段的初步研究

自从1995年Mathies^[1]首次将微流控芯片毛细管凝胶电泳用于基因测序研究以来,DNA片段的分离已成为微流控芯片应用的重要领域之一.最早应用于DNA分析的微流控芯片是玻璃芯片,聚合物微流控芯片以其品种多、成本低、易于加工,与玻璃芯片相比具有封接温度大大降低,微通道内电渗流显著减小等特点,已被成功应用于DNA片段的分离^[2,3].     

含[AMIM]BF4的聚甲基丙烯酸甲酯基凝胶聚合物电解质的制备与改性

用两步法合成了离子液体1-烯丙基-3-甲基咪唑四氟硼酸盐（[AMIM]BF4）,将聚甲基丙烯酸甲酯(PMMA)引入离子液体[AMIM]BF4中,制备出含离子液体[AMIM]BF4的新型凝胶聚合物电解质,采用非质子溶剂、纳米SiO2等对其进行了改性。 用FT-IR、交流阻抗（AC）、TG、SEM等测试技术对其结构和性能进行了表征。 结果表明,非质子溶剂碳酸丙烯酯、碳酸二甲酯和纳米SiO2的加入使聚合物电解质的室温离子电导率增大,达5.25×10-3 S/cm;电导率与温度的关系符合Arrhenius方程;几种凝胶聚合物电解质的热分解温度均高于300 ℃,显示出良好的热稳定性。     

Long‐lived species generated via irradiation of poly(methyl methacrylate) containing pyrene

The fate of long‐lived species [pyrene (Py) radical cations and Py–cyclohexadienyl‐type radicals] generated by electron‐beam irradiation at room temperature in poly(methyl methacrylate) (PMMA) doped with Py is described. The separation of reacting solute intermediates and the relaxation phenomena seem to be the main factors limiting the reactivity of long‐lived Py species in the PMMA matrix. The temperature‐stimulated recombination of ionic species in PMMA doped with Py results in Py excited‐state formation. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 4110–4118, 2001     

Electrical Percolation of Carbon Black Filled Poly （ethylene oxide） Composites in Relation to the Matrix Morphology

The present work studies the electrical conduction performance of carbon blaak (CB) filled poly(ethylene oxide) (PEO) composites. The addition of CB leads to reduced matrix crystallinity as the fillers which are partly situated inside the lamellae and hinder the growth of PEO crystallites. As a result, the electrical percolation behavior is related with the matrix morphology.     

Study of Polymer-Cement Composite Containing Portland Cement and Aqueous Poly (methyl methacrylate) Latex Polymer by Fourier-Transform Infrared (FT-IR) Spectroscopy

The polymer-cement composite is an immiscible band having modified morphology. Polymer phase improves the toughness of brittle cement and has a reinforcing effect, and interactions between cement components and polymers provide stability. In this study, polymer latex [poly(methyl methacrylate), PMMA] – cement paste was prepared with different weight proportions of polymer content. The main scientific objective of this report has been the analysis and the prediction of high strength with the aim of understanding the interactions of PMMA polymer with Portland cement after hydration reaction of cement pastes and curing the specimens for 28 days. The samples were studied by Fourier transform infrared (FT-IR) spectroscopy. The results are critically examined. It is shown that bands support the interaction of PMMA with cement in the composite.     

Modification of Cu3(BTC)2 with Cobalt Ion for Adsorption and Visualized Detection of Formaldehyde Gas

In this paper, cobalt ion was employed to modify Cu₃(BTC)₂ to improve the adsorption property for formaldehyde gas. The cobalt ion was doped during the synthesis of Cu₃(BTC)₂ to form a product of CuCo-BTC. As the optimization assay indicated, when the molar ratio of the Co²⁺/Cu²⁺ was 3/17, the adsorption amount for formaldehyde gas achieved the maximum, which is 1.6-fold to that of Cu₃(BTC)₂. ICP-MS, XPS, XRD, FT-IR, SEM and N₂adsorption–desorption were used to investigate the structure and property of the CuCo-BTC. Subsequently, the adsorption kinetic process of the CuCo-BTC was assessed, the result suggests it coinciding to the pseudo first-order kinetic model which belongs to the physical adsorption process. The further assays indicated the CuCo-BTC possessing higher and faster colorimetric response to formaldehyde with indicator than other metal organic framework materials or common indicators. Therefore, it was utilized to fabricate a functional paper chip to perform the visualized detection of formaldehyde gas. The result displayed a sensitive response to formaldehyde gas in the concentration range of 0.02 ~ 0.08 mg/m³. Besides, the whole colorimetric assay merely takes 150 s, suggesting a favorable application prospect in the on-site test of detrimental gas.     

Electrical and optical characterization of PMMA doped with Y0.0025Si0.025Ba0.9725 (Ti(0.9)Sn0.1)O3 ceramic

<正>Poly(methylmetacrylate)(PMMA)/Y_(0.0025)Si_(0.025)Ba_(0.9725)(Ti_((0.9))Sn_(0.1))O_3(YBTS) composites were prepared at different weight ratios of YBTS(0 wt%,5 wt%,10 wt%and 20 wt%YBTS) in order to investigate effect of YBTS additions on the electrical and optical properties of PMMA host.The electrical properties(impedance,dielectric constant dielectric loss and AC conductivity) were studied in the frequency range 10 kHz-1 MHz and in temperature range 20-90℃.Upon increasing the contents of YBTS ceramic,we observed a reduction in the impedance and an increase in the dielectric constant,dielectric loss and AC conductivity of PMMA host.We also found that the relaxation process at high YBTS contents was due to relaxation in the ionic conductivity.The absorption coefficient(α) has been determined in the wavelength range 230-800 nm at room temperature for all YBTS-PMMA composites.Moreover,the addition of YBTS ceramic highly enhances the UV absorption of PMMA host especially below 300 nm.Addition of 20 wt%YBTS ceramic to PMMA host decreases the optical energy gap from 5 eV to 3.41 eV.Correlations between electrical,optical and SEM results are reported.     

一个新型钌(II)配合物对F－的双重光谱识别

采用紫外-可见光谱和荧光光谱滴定方法研究了钌(II)配合物[Ru(bpy)(H2iip)2](ClO4)2 [bpy＝2,2’-联吡啶, H2iip＝2-吲哚基-咪唑并[4,5-f][1,10]-邻菲罗啉]在DMSO溶液中对卤素离子的识别性质. 结果表明该配合物能比色和荧光双重光谱高选择性识别F－.