阻燃抑烟沥青混合料研究进展

为梳理阻燃抑烟沥青混合料研究现状,阐述了沥青热解与烟气产生的相关过程。其次,对现有的阻燃抑烟性能测试方法进行了总结,并将沥青烟气释放量测试方法分为质量损失法与吸附法。对阻燃沥青、阻燃纤维、多孔型阻燃路面三种沥青路面阻燃技术进行了介绍,并分析了降低拌合温度与添加抑烟组分两种抑烟手段的特点。针对沥青路面阻燃抑烟研究热点,提出了沥青路面阻燃抑烟后续研究要点与方向。     

氢氧化铝/有机改性蒙脱土复合改性沥青性能研究

采用氢氧化铝(ATH)和两种有机改性蒙脱土(OMMT-C、OMMT-F)对沥青进行阻燃抑烟改性,旨在提高隧道沥青路面的阻燃抑烟性能。通过测试三大指标来评价ATH/OMMT复合改性沥青的常规性能,测试极限氧指数(LOI)与烟密度(SDR)来评价其阻燃抑烟性能,利用动态剪切流变(DSR)试验研究其流变性能。基于综合指数法优选出ATH/OMMT复合改性沥青的最佳复掺配比,通过热重(TG)试验分析了ATH/OMMT复合改性沥青的热解燃烧特性并建立了阻燃性能预测模型。研究结果表明,ATH/OMMT复合阻燃剂提高了沥青的稠度与软化点,降低了沥青的低温性能。当ATH掺量为10%(质量分数),OMMT-C掺量为3%(质量分数)时,复合改性沥青的综合性能最优,其极限氧指数大于23%,符合路用阻燃沥青的标准,同时烟密度相对基质沥青降低了33.9%,初始分解温度较基质沥青提高了3~6 ℃,分解残余量提高率最高可达61.3%。ATH/OMMT-C复合阻燃剂通过阻隔热交换通道提高了沥青的阻燃抑烟性能,通过增加沥青的弹性成分提高了沥青的复数模量与车辙因子,以及高温抗变形能力。     

聚氯乙烯阻燃抑烟研究进展

综述了近年来在聚氯乙烯阻燃抑烟方面的研究进展,介绍了新型聚氯乙烯阻燃抑烟剂、阻燃抑烟技术和阻燃抑烟的表征及分析方法。随着人们对环保的日益重视,聚氯乙烯阻燃和抑烟技术必然向低毒或无毒、高效的方向发展。     

ATH/OMMT复合改性沥青阻燃抑烟性能与机理分析

对ATH、OMMT改性沥青的阻燃抑烟性能进行了研究,将ATH、OMMT两种改性剂按照不同配比进行复配,研究了不同配比的复合阻燃剂对沥青常规性能、阻燃抑烟性能的影响,评价了不同配比复合阻燃剂的协同效果,并采用X射线衍射(XRD)、红外光谱(FTIR)等手段研究了沥青改性前后的微观结构变化,采用扫描电镜(SEM)、X射线能谱仪(EDS)等手段研究了沥青燃烧后的碳层结构及元素组成,探究了ATH/OMMT复合阻燃体系的阻燃机理.结果 表明,单掺OMMT对沥青阻燃抑烟性能的提升非常有限,而单掺ATH虽然能有效提高沥青的阻燃性能但需要的掺量较大.OMMT与ATH间存在良好的协同效果,能够有效提高沥青的阻燃性能和抑烟性能.不同掺量(1％、3％、5％)的OMMT在SBS改性沥青中均形成了剥离型纳米复合材料,在OMMT改性沥青的红外光谱中,1 092 cm-1、1 032 cm-1、517 cm-1、463 cm-1四处特征峰的峰面积指数与沥青中OMMT掺量之间展现出良好的线性关系.在ATH/OMMT复合阻燃抑烟沥青的热解燃烧过程中,ATH受热产生的Al2 O3依附于聚集在沥青表面的OMMT片层上,形成了一种耐火的致密复合阻隔层,可以高效地阻隔沥青燃烧过程中的热量及物质传递,减少了可燃轻质组分的析出量,增加了成碳比例,使得ATH/OMMT复合改性沥青具备良好的阻燃抑烟性能.     

聚氯乙烯阻燃抑烟技术研究进展

介绍了聚氯乙烯阻燃抑烟机制及其分类,阻燃抑烟剂按组分不同分为无机、有机和复合型阻燃抑烟剂,综述了阻燃抑烟剂反应机制和性能的研究进展,展望了未来的发展和应用趋势。     

ABS阻燃与抑烟性的研究

对ABS树脂的阻燃、抑烟性等性能进行了研究和探讨。实验结果表明,采用共混、添加复合阻燃剂、抑烟剂的方法可以有效地获得阻燃、抑烟性及其他性能皆优的ABS树脂体系。     

微胶囊技术阻燃环氧树脂研究进展

综述了采用微胶囊技术包覆聚磷酸铵和红磷用于阻燃环氧树脂的研究进展,详细介绍了其阻燃效果和阻燃机理等。指出应扩大微胶囊技术的应用范围,并还应积极开展微胶囊工艺、阻燃剂复配、提高力学性能、抑烟性能等研究,以提高环氧树脂的适用性。     

低温固化阻燃环氧胶粘剂的研制

介绍了一种(-3~4)℃/30 h固化、阻燃抑烟性能优异、低毒、具有良好粘接强度和综合性能的环氧树脂胶粘剂。论述了阻燃胶粘剂配方的选择、环氧树脂的低温固化机理和固化性能,讨论了无机复合阻燃抑烟填料对胶粘剂性能的影响。     

磷钼酸铵的制备及性能

对新型阻燃抑烟剂——磷钼酸铵的制备和性能进行了研究;利用XRD、IR、DSC和TG对所制备的磷钼酸铵进行了表征,为磷钼酸铵的应用提供了理论基础。将磷钼酸铵加入PVC中,并与常用的阻燃抑烟剂Sb2O3、MoO3、Al(OH)3等进行对比,通过对阻燃材料氧指数和烟密度的测试表明,磷钼酸铵具有良好的阻燃抑烟性能;力学性能测试表明,磷钼酸铵与高分子材料具有良好相容性,是一种性能出众的新型阻燃抑烟剂,具有广阔的应用前景。     

纳米阻燃抑烟PVC的研究进展

PVC是一种应用广泛的高分子材料,但因其具有热稳定性差、易燃烧、发烟量大的缺点而限制了发展,因此PVC的阻燃与抑烟成为阻燃科学研究领域的关键问题之一。纳米型阻燃抑烟剂克服了传统型阻燃抑烟剂添加量大、阻燃抑烟效果不明显的缺点,为研究和解决PVC阻燃抑烟提供了一个新途径。本文介绍了PVC纳米阻燃抑烟剂的制备方法、表征手段及其在PVC中的应用以及PVC降解、阻燃与抑烟的表征,最后简要论述PVC阻燃抑烟的发展趋势。     

乙苯,苯乙烯的生产及合成乙苯,苯乙烯催化剂的研究进展

苯乙烯是重要的石油化工原料。本文介绍了国内外苯乙烯生产的发展概况，合成乙苯，苯乙烯所用的催化剂种类，并就苯乙烯生产及催化剂的发展趋势提出了自己的观点。     

Synthesis and characterization of homopolymers and copolymers of various acrylates and acrylonitrile

Various homopolymers and copolymers of methyl acrylate, ethyl acrylate, butyl acrylate, and acrylonitrile in different feed ratios were synthesized. These were characterized by IR, ¹³C-NMR, DSC, DTA, and TGA. Spectroscopic characterization helped in differentiating copolymers of different mol ratios. Thermal analysis revealed different degradation patterns for homopolymers and copolymers. The temperature and energy changes associated with various phase transitions were dependent on the chemical composition of homo- and copolymers, as expected. © 1993 John Wiley & Sons, Inc.     

生物质气化及生物质与煤共气化技术的研发与应用

总结了生物质原料的特点及生物质单独气化的缺点;介绍了国内外生物质气化技术及生物质与煤共气化技术的研发与应用现状;分析了在此领域国内外的发展趋势与前景;概括了开展生物质与煤共气化技术研发的意义。     

Electronic structures and reactivities of monometallic and bimetallic clusters of Au and Cu

The variation of the Au 4f binding energy of Au clusters with the cluster size has been established by measuring the binding energies of clusters whose size distributions were independently determined by HREM and STM. The binding energy increases significantly when the cluster size is less than 2 nm. Au-Cu bimetallic clusters of the composition Cu₃Au have been deposited for the first time on carbon substrates. The shifts in the core level binding energies of the bimetallic clusters show the effect of alloying in the case of large clusters, but show effects of both alloying and cluster size in the case of the small clusters. The interaction of CO with Cu₃Au clusters is stronger than with a bulk Cu metal. The interaction of CO with small Cu clusters also seems to be stronger than with bulk Cu or with large Cu clusters.     

钾盐资源及钾肥供需情况分析及预测

阐述了国内外钾盐资源及钾肥生产现状,对国内外钾盐的供需形势进行了分析及预测,从资源、原材料、国际市场三方面提出了解决我国钾盐短缺的措施。     

Kinetics and Mechanism of Oxidation of Mono- and Polyacetals

Abstract

Kinetics and mechanisms of oxidation of 6 acetals by molecular oxygen and ozone in liquid phase have been studied. Reaction with molecular oxygen (70°C, 15–16 hr) leads to the formation monoethers of the corresponding glycols with 68–90% selectivity. Salts of metals and complexes with crown-ethers have increased the reaction rate significally. Ozone have reacted with acetals with formation similar products. The mechanisms of intermediate stages have been proposed.     

Comparison of the Adhesion and Cohesion of Triblock and Random Copolymers of Styrene and Butadiene

A substantially greater detachment energy is required to strip a polyethylene tereph-thalate (Mylar) film from a styrene-butadiene-styrene (SBS) triblock copolymer compared to that for peeling from a random styrene-butadiene (SBR) copolymer. This is true even though the intrinsic interaction between the Mylar and each elastomer is expected to be similar because of their virtually identical chemical composition. It is proposed that this difference in peel strength (between the SBS and SBR) is a consequence of the much higher dissipative capacity of the former elastomer. Another manifestation of this is the higher cohesive tear strength of the SBS compared to the SBR. Extents of energy dissipation within each elastomer during detachment of the Mylar adherend are consistent with the hypothesis that the average maximum stress experience before detachment is some similar fraction of each elastomer's tensile strength.     

责任和责任心的涵义与结构

责任是人应主动承担的角色义务和对其因过失所造成后果应承担的责罚.有两层涵义:一是义务;二是后果.责任心是个体自觉做好分内事务和履行道德义务的心理倾向,是个性心理品质成分中自我特征维度上的重要内容.责任心具有两个方面的涵义:一是角色分内职责;二是角色道德义务.责任心是一种通过责任认知、责任个性和责任适应的动态形式表现出来的静态品质,责任心是责任心过程结构与责任心关系结构相互制约、相互影响的统一体.     

二甲基二烯丙基氯化铵和丙烯酰胺的合成及应用

用复合引发体系(过硫酸盐-偶氮类引发剂)和脂肪胺类氧化还原体系引发,在实验室获得了单体转化率≥98%,特性粘数高于13.6 dL/g的阳离子共聚物PDA,探讨了控制聚合物分子量的影响因素.     

Wetting properties of homopolymers and copolymers of pentafluorostyrene and methylacrylate and homopolymer blends

Polypentafluorostyrene (PPFS), polymethylacrylate (PMA), and poly(pentafluorostyrene-co-methylacrylate), poly(PFS-co-MA) were prepared and the wetting characteristics of polymer blends of PPFS and PMA were compared with that of poly(PFS-co-MA) via contact angle measurements. The critical surface tension of polypentafluorostyrene was found to be 22.6 dyne/cm, which is comparable to the value reported for polytrifluoroethylene (22 dyne/cm). The critical surface tension of poly(PFS-co-MA) is not linearly related to its composition. The polymer blends of PPFS and PMA exhibit significant surface enrichment of the fluoropolymer. The harmonic-mean method¹ was employed to determine surface tensions of these polymers and many known polymers. It is found that the method produces useful surface tension data provided the contact angle values are derived from testing liquids of dissimilar polarity.