聚甲基丙烯酸甲酯Langmuir—Blodgett复合膜及其在光电导体中…

制备了聚甲基丙烯酸甲酯（ＰＭＭＡ）ＬＢ复合膜，将其作为阻挡层首次应用于机能分离型光电导体领域。从π－Ａ曲线发现ＰＭＭＡ单分子膜具有表面压力的各向异性和松弛特性。ＴＥＭ照片显示，ＰＭＭＡ分子链在复合膜中有序排列。转移比、ＵＶ和ＸＰＳ研究表明，复合膜沉积均匀。以ＰＭＭＡ－ＬＢ复合膜作为阻挡层的光电导体表面充电电位Ｖ０＝１５１８Ｖ，光照１ｓ后的光衰百分率△Ｖ１ｓ＝５０．１６％，半衰期ｔ１／２＝０．９３ｓ     

醇／水混合液分离用聚乙烯醇复合膜的渗透汽化特性

制备了聚乙烯醇（ＰＶＡ）／聚丙烯睛（ＰＡＮ）渗透汽化复合膜，研究了交联剂用量、底膜结构、进料液组成、操作温度等因素对膜的渗透汽化性能的影响．发现ＰＶＡ／ＰＡＮ复合膜对水／醇混合液表现为水优先透过，进料液中乙醇浓度在６０～９９ｗｔ％的范围内，渗透通量Ｊｔ与温度之间符合Ａｒｒｈｅｎｉｕｓ关系，选择分离系数αＷ／Ｅ也随温度上升而增大．进料液为９５ｗｔ％的乙醇／水混合液时，７５℃下Ｊｔ高达３００～４５０ｇ／ｍ２ｈ，αＷ／Ｅ为８００～１１００．对异丙醇／水、异丁醇／水及甘油／水混合体系，复合膜显示出更为优秀的透过、分离性能．就膜的化学、物理结构与其渗透汽化性能间的关系进行了讨论．     

聚苯胺/PA-6导电复合膜的电化学合成与性能

用电化学复合法，以聚己内酰胺为膜基，通过氟硼酸掺杂，使苯胺电解聚合，制成一种新型的聚苯胺／聚己内酰胺（ＰＡｎ／ＰＡ－６）复合膜，考察了电流密度、掺杂剂浓度及苯胺浓度等因素对导电复合膜的电导率、机械性能的影响。     

功能聚间苯二胺膜用于免疫传感器分析

以电化学聚合法在石墨电极上获得聚间苯二胺膜（ＰＭＰＤ），并建立了快速、灵敏的膜质量检验方法：辣根过氧化物酶（ＨＲＰ）标记ＰＭＰＤ膜－邻苯二胺（ＯＰＤ）反应法，对聚合、活化等条件作了研究；进一步制成了检测乙肝表面抗原（ＨＢｓＡｇ）和检测鼠免疫蛋白（ＭＩｇＧ）的免疫电极，对血清样品作了检测．结果表明：２．５Ｖ电池电压下，于含０．１２ｍｏｌ／ＬＭＰＤ的１．２ｍｏｌ／ＬＨ２ＳＯ４中聚合２０ｍｉｎ，再以３０ｇ／Ｌ浓度的戊二醛活化４ｈ，所得ＨＲＰ标记电极及免疫电极重现性好；检测ＨＢ－ｓＡｇ和ＭＩｇＧ的线性范围分别为０．１～３．２ｍｇ／Ｌ及０．１～１０ｍｇ／Ｌ     

聚苯胺／含联苯结构聚芳砜导电复合膜的研究

采用溶液共混法得到了聚苯胺／含联苯结构聚芳砜导电复合膜。该复合膜有良好的力学性能和导电性能，对其导电规律进行了探讨。热分析结果表明复合膜有良好的热稳定性，用扫描电镜观察了复合膜的微观形貌，表明ＰＡｎ与ＬＰＥＳ的共混相容性较好。     

由聚苯胺粒子组成的电流变液的研究

由经碱处理的掺杂态聚苯胺（ＰＡｎ）制得高介电常数的半导体ＰＡｎ粒子，将其悬浮于电绝缘油可组成电流变液，讨论了电流变（ＥＲ）液的静态屈服应力（τ＿ｓ），电流密度等性能与ＰＡｎ的介电常数（ε＿ｐ），导电率（σ），体积分数和应用电场强度的关系。对导电率相同的ＰＡｎ粒子，用氨水处理的ＰＡｎ粒子ε＿ｐ较用ＮａＯＨ液处理的高，前者在σ足够低如σ≤１．０×１０￣（－７）／ｃｍ时，ＥＲ液的τ＿ｓ随偶极系数的平方（β￣２）的增大而呈现非线性增加；后者ＥＲ液的τ＿ｓ随β￣２的增大出现一最大值．结果表明：由聚苯胺粒子可组成高电流变活性的无水ＥＲ液．     

聚(丙烯酰胺-丙烯酸)/聚(丙烯酰胺-二甲基二烯丙基氯化铵)聚电解质复合溶液动态光散射研究

通过动态光散射、粘度和透光率测定，研究了聚（丙烯酰胺 丙烯酸）［Ｐ（ＡＭ ＡＡ）］／聚（丙烯酰胺 二甲基二烯丙基氯化铵）［Ｐ（ＡＭ ＤＭＤＡＡＣ）］聚电解质复合溶液的结构和性能．结果表明，Ｐ（ＡＭ ＡＡ）与Ｐ（ＡＭ ＤＭＤＡＡＣ）复合比、溶液浓度和氯化钠用量影响溶液中复合物的构象和流体力学半径．Ｐ（ＡＭ ＡＡ）与Ｐ（ＡＭ ＤＭＤＡＡＣ）分子链间适度的库仑相互作用，可形成均相Ｐ（ＡＭ ＡＡ）／Ｐ（ＡＭ ＤＭＤＡＡＣ）聚电解质复合溶液，复合物具有较伸展的构象和较大的流体力学半径，因而溶液粘度较高．Ｐ（ＡＭ ＡＡ）与Ｐ（ＡＭ ＤＭＤＡＡＣ）分子链间过强的库仑相互作用或小分子电解质的屏蔽作用，可使复合物构象卷曲，结构紧缩，流体力学半径减小，甚至产生相分离，导致溶液粘度降低．     

POM／EVA共混物的研究

用力学测试、扫描电镜（ＳＥＭ）、热分析（ＤＳＣ）等手段研究了聚甲醛（ＰＯＭ）与乙烯－醋酸乙烯酯共聚物（ＥＶＡ）共混物（ＰＯＭ／ＥＶＡ）的力学性能及其微同形态；用聚甲醛与马来酸二丁酯（ＤＢＭ）的接枝物（ＰＯＭ－ｇ－ＤＢＭ）作相溶剂，能改变共的两相间的粘结力，从而提出了共混物的力学性能，ＳＥＭ观察表明接枝物的加入改变了ＰＯＭ／ＥＶＡ共混物的断裂方式，微观形态及结晶性能，对其热性能影响不大；通过改变ＰＯ     

修饰微带金电极上细胞色素C电极过程的热力学研究

研究了细胞色素Ｃ（Ｃｙｔ．Ｃ）在一种新的电子转移促进剂４，６－二甲基－２－巯基嘧啶修饰微带金电极（ＤＭＭＰ／Ａｕ）上的氧化还原热力学；求得Ｃｙｔ．Ｃ在ＤＭＭＰ／Ａｕ电极上反应的标准电极电位Ｅ＾ｏ，熵变△Ｓ＾ｏ，焓变△ＩＩ＾ｏ及Ｇｉｂｂｓ自由能的改变△Ｇ１０值分别为：０．２７２Ｖ（ｕｓ．ＮＨＥ），－１２３．７Ｊ．ｍｏｌ＾－＾１，－６３．１ｋＪ．ｍｏｌ．ｍｏｌ＾－＾１和－２６．２ｋＪ．ｍｏｌ＾－＾１（     

甲基丙烯酸甲酯 - 甲基丙烯酸共聚物/梯形聚苯基硅倍半氧烷原位共混体系的性能研究

甲基丙烯酸甲酯 甲基丙烯酸共聚物（Ｐ（ＭＭＡ ＭＡＡ））与低分子量或高分子量梯形聚苯基硅倍半氧烷（ＰＰＳＱ）的共混物经原位聚合法制成．用光学透明法、荧光光谱、ＤＳＣ等技术研究了该共混体系的相容性及组分间的相互作用及结构转变．结果表明，当ＰＰＳＱ含量较小时，由于ＰＰＳＱ与Ｐ（ＭＭＡ ＭＡＡ）间存在着较强的氢键作用，该共混体系在一定配比下相容，且低分子量ＰＰＳＱ与Ｐ（ＭＭＡ ＭＡＡ）间的相容性较好．当ＰＰＳＱ的含量≤１％时，ＰＰＳＱ的加入对该共混物的Ｔｇ影响不大，但其Ｔｆ随ＰＰＳＱ含量增加而增大．此外，还测试了Ｐ（ＭＭＡ ＭＡＡ）／ＰＰＳＱ原位共混物的硬度及冲击强度．     

细菌纤维素(BC)增强PVA/PVP复合水凝胶的制备及性能表征

通过冷冻-熔融法制备了细菌纤维素/聚乙烯醇/聚乙烯吡咯烷酮(BC/PVA/PVP)双网络复合水凝胶,并采用X射线衍射,红外光谱,扫描电镜,力学性能测试等手段对凝胶的结构和性能进行表征.研究发现PVA、PVP通过氢键作用均匀地吸附于纤维微丝周围,将BC纤维有效地分开,因而干燥后的复合凝胶在热水中浸泡后仍可恢复原状;X射线...     

Physical properties of CdS-poly (vinyl alcohol) nanoconducting composite synthesized by organosol techniques and novel application potential

A nanocomposite of poly (vinyl alcohol) (PVA) reinforced with various contents of CdS was synthesized by organosols reaction with particle size in the range of nanoscale. The influence of CdS content on the network structure of PVA matrix such as particle size distribution, gel fraction (GF), equilibrium water content (EWC), water absorption (WA), extent of filler reinforcement (γ), volume fraction of polymer (V_s) number of elastically effective chains (NEC), and X-ray diffraction (XRD) were investigated. The affine and phantom models for physical crosslinks were used to predict the nature of crosslinks. The thermal behavior of PVA-CdS composites has been studied by differential thermal analysis (DTA), Thermogravimetry (TG) and differential scanning calorimetry (DSC). The dc conductivity of the PVA system reinforced with CdS as a function of concentration and temperature has been presented. The PVA composite exhibits considerably high electronic conductivity which increases linearly with the increase of CdS content. The conduction mechanism in PVA-CdS composites is governing by hopping mechanism. The effects of CdS loading and temperature on the thermal conductivity (λ) and specific heats (C_p) were investigated. The antistatic properties and electromagnetic wave shielding effectiveness (EMI) of PVA-CdS composites has been also investigated. The optical properties such as absorbance and transient photo current under applied voltage of PVA-CdS composites were tested. The mechanical properties of PVA-CdS composites were investigated in details. It is proved that the PVA-CdS composites can be effectively used for linear thermistors, antistatic charge dissipation, EMI in the encapsulation of electronic devices, in woven texturing, optical switch and solar cell fabrication.     

层状纳米纤维素膜/PVA复合水凝胶的制备与力学性能研究

采用叠层复合与物理相分离的方法制备了层状纳米细菌纤维素(BC)膜/聚乙烯醇( PVA)复合水凝胶.研究了聚乙烯醇的质量百分数、BC膜的复合层数以及制备条件对复合水凝胶力学性能的影响;通过扫描电镜( SEM)观察比较了复合水凝胶中BC膜层与PVA界面结合情况.结果表明,复合水凝胶的力学性能与PVA的质量百分数和BC膜含水...     

Preparation and properties of poly(vinyl alcohol)/exfoliated α-zirconium phosphate nanocomposite films

In this work, poly(vinylalcohol)(PVA)/exfoliated α-zirconium phosphate(e-α-ZrP) nanocomposites of various compositions were created by a solution casting method. The α-ZrP compound was synthesized by refluxing. The characteristic properties of the PVA/e-α-ZrP composite films were examined by thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and tensile tests. Tensile tests indicated that with the loading of e-α-ZrP, the tensile strength and the elongation at break were increased by 17.3% and 26.6% compared to neat PVA, respectively. It is noteworthy that optimum film properties were obtained with 0.8 wt% e-α-ZrP, and higher proportions of e-α-ZrP, may be related to the aggregation of e-α-ZrP particles and deterioration of the film properties. On the whole, the nanocomposite PVA/e-α-ZrP systems had mechanical and thermal properties which were superior to that of the neat polymer and its conventionally filled composites.     

The effect of silica morphology on properties of PVA/silica nano-composites

Two kinds of poly(vinyl alcohol)(PVA)-silica composites were prepared with different methods. One composite was prepared by directly mixing PVA with 80 nm silica nano-particles which were made from tetraethoxysilane(TEOS). The another was obtained by the mixing PVA and hydrolyzed TEOS in the presence of acid-catalyst. The properties of the two PVA/silica hybrids were characterized by means of scanning electron microscopy(SEM), UV-Visible spectroscopy,solubility tests, limiting oxygen index(LOI) test, tensile test and dynamical mechanical analysis(DMA), respectively. The results indicate that PVA-TEOS composites(PT for short) display more transparency than PVA-silica nano-particles hybrids(PS for short). At the same time, The PT composites presented more excellent performance than PS in water resistance, fire resistance and mechanical properties. Moreover, the Tg of PT increased with increasing TEOS content, while that of PS decreased.     

Surface modified graphene oxide/poly(vinyl alcohol) composite for enhanced hydrogen gas barrier film

A series of novel polyethyleneimine (PEI) modified graphene oxide (PEI-mGO) filled poly(vinyl alcohol) (PVA) nanocomposite (PEI-mGO/PVA) films were prepared by solution-casing for hydrogen gas barrier applications. Hydrophilic PEI was used to simultaneously reduce and modify graphene oxide sheets, thereby facilitating a homogeneous dispersion of PEI-mGO in the PVA matrix. The effects of PEI-mGO on the morphology and properties of the nanocomposite films were examined by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis and field emission scanning electron microscopy. Analogous GO/PVA composites were also prepared and characterized for comparative purposes. The PEI-mGO/PVA nanocomposites showed higher thermal and mechanical stability as well as remarkable improvement in hydrogen gas barrier properties compared to the PVA film; specifically, the PEI-mGO/PVA film having 3.0 wt% of PEI-mGO content exhibited almost 95% decrease in GTR and permeability values compared to PVA film.     

Relationship between the polymer/silica interaction and properties of silica composite materials

Cast film composites have been prepared from aqueous polymer solutions containing nanometric silica particles. The polymers were polyvinyl alcohol (PVA), hydroxypropylmethylcellulose (HPMC) and a blend of PVA‐HPMC polymers. In the aqueous dispersions, the polymer–silica interactions were studied through adsorption isotherms. These experiments indicated that HPMC has a high affinity for silica surfaces, and can adsorb at high coverage; conversely, low affinity and low coverage were found in the case of PVA. In the films, the organization of silica particles was investigated through transmission electron microscopy (TEM) and small‐angle neutron scattering (SANS). Both methods showed that the silica particles were well‐dispersed in the HPMC films and aggregated in the PVA films. The mechanical properties of the composite films were evaluated using tensile strength measurements. Both polymers were solid materials, with a high‐elastic modulus (65 MPa for HPMC and 291 for PVA) and a low‐maximum elongation at break (0.15 mm for HPMC and 4.12 mm for PVA). In HPMC films, the presence of silica particles led to an increase in the modulus and a decrease in the stress at break. In PVA films, the modulus decreased but the stress at break increased upon adding silica. Accordingly, the polymer/silica interaction can be used to tune the mechanical properties of such composite films. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1134–1146, 2006     

Surface Modification of Carbon Nanotube by Poly(ethylene glycol) for the Preparation of Poly(vinyl alcohol) Nanocomposite

Herein, PEGylated multi-walled carbon nanotube (MWNT) was prepared for the successive fabrication of poly(vinyl alcohol) PVA/MWNT nanocomposite film by solution casting. The surface modified MWNT showed a good colloidal stability in a polar solvent, i.e., water. Also, the PEGylated MWNT had an improved dispersion stability in aqueous PVA solution. The mixture of PEGylated MWNT and PVA dissolved in water was film casted and the dispersion uniformity and corresponding improvement of electrical conductivity were investigated. The electrical conductivity of PVA/modified MWNT composite film was three-fold higher than that of PVA/pristine MWNT composite film due to the much improved distribution uniformity of modified MWNT in PVA matrix.     

Thermal transfer,interfacial, and mechanical properties of carbon fiber/polycarbonate-CNT composites using infrared thermography

Electrical resistance (ER) and thermogram measurements were used to evaluate thermal transfer, interfacial and mechanical properties of carbon fiber reinforced thermoplastic polycarbonate composites. Carbon nanotubes (CNTs) were fairly uniformly dispersed in polycarbonates using a solvent dispersion method. The CNTs were then further dispersed with an additional time using a twin screw extruder. The effect of CNT on the mechanical properties of polycarbonate was evaluated using a thin film tensile test. For thermogram to evaluate the transferring temperature the composite was placed on a hotplate and copper wires were inserted in the composite at uniform thickness intervals. Due to the different inherent thermal conductivity of CNT, ER was measured to detect thermal changes in the carbon fiber/CNT-polycarbonate composites. The comparison of interlaminar shear strength (ILSS) was to investigate effects of CNT on mechanical and interfacial properties. The uniform distribution of CNTs affected all of these properties in carbon fiber-reinforced thermoplastic composite. Furthermore, heat transfer and heat release become more rapid with the addition of CNT than the without case.     

ANALYSIS AND CHARACTERIZATION OF MICROSCOPIC MORPHOLOGY AND ORIENTATION STRUCTURE OF POLYANILINE POLYMERIZED IN A CONSTANT MAGNETIC FIELD

Conductive polyaniline(PAn-_M and PAn-_O) doped with dodecylbenzene sulfonic acid(DBSA) was synthesized by using emulsion polymerization method in the presence of a constant magnetic field(0.4 T) and the absence of magnetic field, respectively.The effects of magnetic field on the microscopic morphology and orientation structure of PAn were generally analyzed and characterized by using transmission electron microscope(TEM),X-ray diffraction(XRD) and through the conductivity anisotropy of unit resistance o...