磷杂菲衍生物的合成及对环氧树脂阻燃性能与热降解行为的影响EI北大核心CSCD

以9,10-二氢-9-氧杂-10-磷杂菲-10-硫化物(DOPS)与对苯醌为原料,合成10-(2,5-二羟基苯基)-10-氢-9-氧杂-10-磷杂菲-10硫化物(DOPS-HQ),采用傅里叶变换红外光谱、核磁共振和高分辨质谱确定其结构,并将其应用于环氧树脂(EP)的阻燃改性。采用热重分析、垂直燃烧、极限氧指数、锥形量热和热重-红外光谱联用(TG-FTIR)等手段研究了阻燃剂DOPS-HQ对EP的热稳定性、热降解行为及阻燃性能的影响。结果表明,阻燃剂DOPS-HQ能提高复合材料的热稳定性和残炭量,改善材料的阻燃性能,降低其热释放速率峰值(PHRR)和总热释放量(THR)。当DOPS-HQ的质量分数为15%时,复合材料的极限氧指数(LOI)值提高至32.5%,达到UL-94 V-0级,其PHRR和THR分别降低了32.7%和38.2%。TG-FTIR结果表明,DOPS-HQ/EP在热降解过程中会产生含磷自由基(PO·,HPO_(2)·,PO_(2)·等)作为H·,O·或HO·自由基的捕捉剂,从而主要在气相中发挥阻燃作用。     

新型阻燃剂中间体DOPO合成与应用概述

新型阻燃荆中间体9，10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)及其衍生物合成的阻燃荆具有高效、无卤、无烟、无毒等性质，不迁移，阻燃性能持久。可用于电子、合成纤维、半导体封装材料阻燃。DOPO在提高高分子材料的阻燃性、热稳定性和有机溶解性的同时，保持了高分子材料的良好物理性能。     

酚醛/聚乙烯醇缩丁醛树脂体系的阻燃改性成膜研究

基于酚醛/聚乙烯醇缩丁醛(PF/PVB)树脂体系开展阻燃改性研究，以乙醇为溶剂，分别采用苯并嗪树脂(BOZ)、10-(2,5-二羟基苯基)-10-氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO-HQ)和羟基乙叉二膦酸(HEDP)这3种改性剂对PF/PVB树脂进行阻燃改性研究，制备了成膜性良好、阻燃性和热稳定性优异的改性酚醛树脂薄膜。结果表明：使用3种改性剂阻燃改性酚醛树脂薄膜的极限氧指数(LOI值)从19.8%分别提高到22.2%、22.4%和26.6%,600℃残炭率分别从31.8%提高到39.9%、45.7%和42.6%,3种阻燃改性剂具有不同的阻燃机理。当体系配比为PF/PVB/HEDP=60/40/5时，树脂薄膜具有最佳的阻燃性能。     

ODOPM阻燃硅烷交联聚乙烯的制备与性能

以9,10-二氢-9-氧杂-10-磷杂菲-10-羟甲基-10-氧化物(ODOPM)阻燃改性硅烷交联聚乙烯(SXPE),探讨了ODOPM对SXPE的阻燃性能、交联过程以及动态力学性能的影响,并分析了阻燃机理。结果表明,质量分数30%的ODOPM能使SXPE的极限氧指数从19.0%提高到25.0%,且通过UL-94 V-0级;动态力学分析表明加入ODOPM后,SXPE的储能模量(E’)增加,ODOPM具有一定的增强作用;热重-红外联用分析表明ODOPM在SXPE体系中主要表现为气相阻燃机理。     

DOPO基阻燃腈纶聚合物的制备与燃烧性能

文中合成了反应型有机磷酸酯功能阻燃剂9,10-二氢-9-氧杂-10-磷杂菲-10-氧甲基丙烯酸酯(DOPOAA),并通过水相沉淀聚合制备了原位共聚改性的阻燃聚丙烯腈,利用红外光谱分析了阻燃聚丙烯腈链段组成,并通过与二乙基膦酸甲基丙烯酸酯(DEAMP)进行对比,详细研究了改性聚丙烯腈的热稳定性和燃烧行为。结果表明,芳环结构有机磷酸酯DOPOAA与单体丙烯腈的竞聚率较为接近;原位共聚改性的聚丙烯腈热稳定性与阻燃性能显著提升;较脂肪结构磷酸酯阻燃剂DEAMP,DOPOAA在气相中也起到了关键的阻燃作用,且在较低的磷含量时即可表现出优异的阻燃性能。当DOPOAA质量分数为15%时,改性聚丙烯腈第1阶段失重温度提高约30℃,热分解残炭量提高约30%,极限氧指数值可达25.1%,热释放速率峰值(pkHRR)降低至598.16 kW/m~2,总释放热(THR)下降为28.91 MJ/m~2,燃烧后的炭层表面致密、平滑,结构完整,阻燃性能优异。     

DOPO-衣康酸-丙烯酸酯类煤炭阻燃抑尘剂的制备及应用

以9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)、衣康酸(ITA)、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、丙烯酸(AA)和甲基丙烯酸缩水甘油酯(GMA)等为原料，K₂S₂O₈为引发剂，十二烷基硫酸钠(k12)和辛基酚聚氧乙烯醚(OP-10)为乳化剂，采用传统的自由基聚合法合成了一种高分子阻燃抑尘剂乳液。采用FT-IR、SEM、TGA等对产品的结构进行表征，并对其成膜柔韧性、保水性、抗风蚀性、抗振荡性等性能进行了测试。结果表明，在m(BA)∶m(MMA)=3∶2,引发剂用量为0.8%(以单体的总质量为基准，下同),乳化剂用量为3%,m(k12)∶m(OP-10)=1∶1,阻燃剂用量为1.25%,反应温度75℃,反应时间1.5h条件下，所制得的乳液稳定，粒径分布均匀，干燥后成膜柔韧性较好。喷洒阻燃抑尘剂的煤样与喷洒水的煤样相比，保水性、抗风蚀性、抗振荡性能都得到了显著提高。     

P元素杂化本征阻燃热塑性聚氨酯弹性体的制备及其性能研究

以9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)和顺丁烯二酸酐(MA)为原料合成含磷单体DOPOMA,将其与二元酸、二元醇进行缩聚反应,得到侧链含磷的端羟基饱和聚酯,再将其与TDI反应合成含磷阻燃热塑性聚氨酯弹性体。采用红外光谱分析(FT-IR)、热重分析(TGA)、极限氧指数(LOI)、扫描电子显微镜(SEM)、万能实验机等测试手段对含磷高聚物的结构、热稳定性、成炭能力、力学性能等进行了分析。结果表明,随着P含量的增加,LOI值逐渐增大,分解温度逐渐提高,残炭率逐渐增大。燃烧炭层致密,P元素的引入对材料的力学性能影响较小。     

双基协同阻燃环氧树脂HPCTP-DOPS/EP的性能研究

单一的磷杂菲、磷腈类阻燃剂的阻燃效果有限,为了改善9,10-二氢-9-氧杂-10-磷杂菲-10-硫化物(DOPS)对环氧树脂(EP)的阻燃效果,将DOPS和六苯氧基环三磷腈(HPCTP)复配应用于EP。在总含P量为1.2wt%时,通过调整磷杂菲和磷腈阻燃剂中含P量的比例,将DOPS和HPCTP复配添加到EP中,制备EP复合材料。利用极限氧指数(LOI)、垂直燃烧(UL-94)、热重(TG)、锥形量热(CONE)、扫描电镜-能量色散X射线谱(SEM-EDS)、热重-红外光谱联用(TG-IR)等测试手段研究不同比例的磷杂菲和磷腈基团对EP热稳定性和阻燃性能的影响,探究双基协同阻燃规律和机制。研究结果表明：P、S元素之间存在协同阻燃作用,当总含P量为1.2wt%时,复合体系中随着含S量的增加,HPCTP-DOPS/EP的LOI值和UL-94等级逐渐升高,当HPCTP和DOPS中的含P量比为0.2∶1时,HPCTP-DOPS/EP的LOI值为30.4%,达到UL-94 V-0级,总热释放量(THR)和热释放速率峰值(PHRR)显著降低,燃烧后形成了更加致密、稳定的膨胀炭层,优于两种阻燃剂单独使...     

新型磷氮阻燃剂TGICA-DOPO的合成及其对乙烯基酯树脂阻燃性能的影响

以异氰尿酸三缩水甘油酯（TGIC）、丙烯酸和9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物（DOPO）为主要原料,合成了一种含P和N元素的新型阻燃添加剂TGICA-DOPO,将其应用在乙烯基酯树脂（VER）中可以制备具有良好阻燃性能的TGICA-DOPO/VER复合材料。通过FTIR光谱、核磁共振（³¹P-NMR和¹H-NMR）等对TGICA-DOPO的分子结构进行了表征;通过极限氧指数（LOI）测试、TGA和DMA研究了TGICA-DOPO/VER树脂体系的阻燃性能和耐热性能。结果表明,当树脂体系中TGICA-DOPO的质量分数为30wt%时,LOI达到35;当体系中TGICA-DOPO的质量分数为25wt%时,树脂浇铸体在800℃下的残炭量提高了322%;FTIR和SEM测试结果表明,燃烧时TGICA-DOPO有助于形成高致密、连续炭层,隔绝了热量和空气向基材的传递,从而在凝聚相中发挥阻燃作用。     

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.     

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.     

Assessment of intakes of mixtures of radionuclides

Australia has several uranium mines and a large number of mineral sand mines, with associated processing facilities. Exposures resulting from these mining and processing operations usually involve intakes of mixtures of radionuclides. This work describes the development of a suite of first order, linear compartment models, based on the ICRP Publication 66 respiratory tract model, and an analytical solution to the decay equations, for assessing the consequences of such intakes. The computer programs based on these models directly compute excretion, organ retention and organ and whole-body doses for intakes of either single radionuclides or any mixture of radionuclides belonging to the same radioactive decay chain. The intake can be via inhalation, ingestion or injection, and can be acute, chronic or of limited duration. The starting concentration and degree of secular (dis)equilibrium can be specified for each radionuclide. No assumptions need to be made about the relative magnitudes of the radioactive half-lives of the different nuclides.     

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.     

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.     

空压机轴承箱蜗壳温度探头油封改造

由于空压机进气侧轴承箱蜗壳温度探头密封效果不好,使空压机及其后续管道受到油污染。后将温度探头的O形圈密封改为骨架油封,杜绝了轴承箱漏油问题。文章简介空压机的结构和技术参数,详细介绍了骨架油封的制作和优点。     

Determination of parameters of microstructural inhomogeneity of deformation of metals by the method of modeling

The article suggests a method of evaluating the microstructural inhomogeneity of deformation of metals by modeling. The method includes the measurement of deformations of metal according to meshes of a dividing grid with small base and the calculation of the distribution parameters of microdeformations in model representation. It is shown that the modeling method makes it possible objectively to evaluate the microinhomogeneity of deformation of metals independently of the chosen mesh size of the dividing grid. New structural characteristics are introduced: the base and wave of variation expressing the degree of crumbling or amalgamation of metal grains by inhomogeneity of deformation.Translated from Problemy Prochnosti, No. 7, pp. 40–44, July, 1991.     

Characteristics of mechanical properties of materials in studies of conditions of attainment of marginal states

It is shown that conditions of attainment of marginal states in the material of structural components are formulated on the basis of analysis of force and deformation criteria of formation and development of destruction. The parameters of these criteria are data on types of structural materials, standard and special characteristics of their mechanical properties, structural forms of considered elements of the equipment, and their operating stress loading. In this case, the construction of a system of state equations for describing interrelation of current damage, external actions, and responses to them is based on the concept of calculating variations in properties of materials at all stages of the design life cycle.