聚苯胺的乳液聚合研究进展

本文详细介绍了聚苯胺(PANI)乳液聚合和微乳液聚合两种聚合方法,并综述了近年来乳液聚合制备PANI研究进展.     

导电聚苯胺及其复合物乳液聚合研究进展

众多导电聚合物中，聚苯胺（PANI）优越的环境稳定性、优异的电化学性能、光学性能使其从导电聚合物中脱颖而出，备受人们关注。但由于PANI的加工性差、力学性能低等缺陷，使其应用受到严重地制约。大量研究表明：乳液聚合可以简化工艺，降低成本，保护环境，还可以有效地改善PANI的可加工性和溶解性。并且，乳液聚合制备PANI的复合材料，可以较好地改善相客性差的缺点。因此，乳液聚合法成为现今PANI领域研究的一大热点。详细介绍了乳液聚合和微乳液聚合两种聚合方法，并综述了近年来乳液聚合制备PANI及其复合物的研究进展。     

反相微乳液聚合机理及模型化处理

在阐述反相微乳液聚合液滴成核及粒子增长机理的基础上，提出了丙烯酰胺反相微乳液聚合过程的物理模式，并对反相微乳液聚合模型化处理时的关键问题作了扼要讨论。     

乳液聚合法合成聚苯乙烯高分子微球及表征

采用乳液聚合法合成高分子微球具有方法简单条件易控等特点,采用乳液聚合法合成了纳米级的聚苯乙烯高分子微球,研究了不同聚合条件下聚苯乙烯高分子微球的表征,结果表明,聚合温度、乳化剂用量、搅拌速度对聚苯乙烯高分子微球的平均分子量、粒径有显著影响。     

高性能硅丙乳液的制备

综述了高性能硅丙乳液的制备路线、制备技术及组成特征,重点分析了微乳液聚合、无皂乳液聚合、纳米技术等在高性能硅丙乳液制备中的应用,探讨了制备硅丙乳液的新型单体的研究进展,展望了高性能硅丙乳液的制备方向。     

超声辐照引发MMA微乳液聚合产物结构表征

表征了超声辐照引发ＭＭＡ微乳液聚合产物的结构,透射电镜观察结果表明,超声辐照引发ＭＭＡ微乳液聚合得到的ＰＭＭＡ乳胶粒平均粒径为３６．５ｎｍ。粒径分布窄;粘度法测试表明得到的ＰＭＭＡ分子量约为５百万;红外光谱法和核磁共振氢谱法测试结果表明,超声辐照引发微乳液聚合得到的ＰＭＭＡ以间同立构为主。     

乳液聚合新技术在含氟聚合物功能性涂层材料中的应用

介绍了几种乳液聚合新技术,如核-壳乳液聚合、微乳液聚合、乳胶型互穿网络聚合(LIPN)等,并对它们在功能型含氟乳液涂层材料研究中的应用进行了展望.     

微乳液聚合物纳米粒子的研究方法

综述了微乳液聚合制备聚合物纳米粒子的研究内容及方法.其主要的研究内容包括:聚合物纳米粒子的化学组成及结构、形态、分子量及分布、热行为以及聚合物纳米粒子的性能等.研究方法有红外光谱、核磁共振、透射电镜、凝胶渗透色谱法、粘度法和光散射等.最后,展望了新型表征手段以及微乳液聚合两个领域的交叉发展.     

聚醚、氨基改性有机硅乳液的研制

采用乳液聚合合成聚醚、氨基改性有机硅乳液,讨论了乳化剂、催化剂、改性剂用量及反应温度、反应时间对乳液聚合的影响;采用水相和逆相乳化法制得有机硅微乳液,并讨论了乳液的性能。     

乳液聚合合成单分散纳米级PMMA微球

采用乳液聚合法制备了单分散性聚甲基丙烯酸甲酯（PMMA）纳米微球,分析了聚合过程中不同单体滴加时间、不同表面活性剂用量、不同引发剂用量以及不同引发剂种类等因素对聚合体系中微球的粒径以及粒径分布的影响,研究表明,PMMA微球的粒径随单体滴加时间、表面活性剂用量、引发剂用量的增加而减小;采用AIBN引发剂制备的微球的粒径较采用KPS引发剂大。     

Estimation of Parameters of Universal Distribution of Moments of Failure of Products

A method is proposed for estimating the parameters of a mixture of exponential and Weibull distributions for which the accuracy of preliminary estimates obtained by graphical analysis is refined in accordance with the criterion of maximum likelihood. The efficiency of the proposed method is supported by the results of statistical modeling.     

Analysis of the rate of propagation of the wave of change of boiling modes

An approximate analytical expression is derived for the velocity of the front of the wave of change of boiling modes on a rod and on a plate. The impact of the Thomson effect and of the heater orientation in the gravity field is included. Adequate agreement is demonstrated between the derived relations and experimental data.     

Evaluation of optical properties of highly scattering media by moments of distributions of times of flight of photons

A novel method for the determination of the optical properties of tissue from time-domain measurements is presented. The data analysis is based on the evaluation of the first moment and the second centralized moment, i.e., the mean time of flight and the variance of the measured distribution of times of flight (DTOF) of photons injected by short (picosecond) laser pulses. Analytical expressions are derived for calculation of absorption and of reduced scattering coefficients from these moments by application of diffusion theory for infinite and semi-infinite homogeneous media. The proposed method was tested on experimental data obtained with phantoms, and results for absorption and reduced scattering coefficients obtained by the proposed method are compared with those obtained by fitting of the same data with analytical solutions of the diffusion equation. Furthermore, the accuracy of the moment analysis was investigated for a range of integration limits of the DTOF. The moment analysis may serve as a comparatively fast method for evaluating optical properties with sufficient accuracy and can be used, e.g., for on-line monitoring of optical properties of biological tissue.     

可燃气体检测报警器测量结果的不确定度评定

本文详细介绍了可燃气体检测报警器示值误差测量结果的不确定度评定方法。     

水三相点复现的不确定度评定

水三相点是开尔文热力学温度的唯一基准点，也是ITS-90国际温标重要的定义固定点。因此，水三相点不确定度分析对整个温标的建立、温度量值传递起着至关重要的作用。近3年来，中国计量科学研究院研制出一系列高质量的水三相点容器，加强了水三相点的研究，为不确定度的分析提供了更为可靠的实验依据。同时，不确定度的分析也是客观评价新研制容器性能的一个重要指标。因此，根据实验结果对新研制容器所复现的水三相点进行了不确定度评定。评定结果表明，其扩展不确定度为0．16mK(k=2．69，P=0．99)。     

心电图机电压测量示值误差测量值的不确定度评定

本文介绍了心电图机电压测量示值误差测量值的不确定度评定与表示方法。     

Estimation of potentialities of methods of summation of direct measurement errors

Conventional methods for summation of direct measurement errors are considered. Conditions under which these methods provide consistent results are stated. It is proposed to utilize for characteristic of the total error, its interval estimator or the half-sum of the value obtained by adding up its arithmetic and geometric random errors.Translated from Izmeritel'naya Tekhnika, No. 4, pp. 10–12, April, 1995.