阻燃剂与阻燃机理

由于石油化工和有机合成技术的进步,推动了合成高分子材料工业的发展。塑料、合成纤维和合成橡胶等形形色色的高分子材料得到广泛应用。合成或天然高分子材料通常都是易燃物,因其燃烧引起的火灾每年都给世界各国带来巨大的经济损失和人身伤亡。为了减少火灾的发生,各国开始大力研究和应用阻燃剂和阻燃材料。许多国家以法律形式规定要求使用高分子阻燃材料。我国也已做出对飞机、轮船、矿井设备等使用阻燃材料的规定;一些省市对建筑用高分子材料的阻燃性能也提出了要求。近些年来在我国阻燃剂的研究与应用已日益受到重视。     

热裂解气相色谱-质谱研究阻燃纤维的结构及烟雾毒性

随着高分子材料的不断开发,涌现出一大批用于阻燃和热辐射防护的耐高温纤维,如Basofil、Kermel、visil、Nomex、P84、PBI和PBO等纤维,除了在衣着领域的应用外,在消防服、工业用阻燃防护服以及汽车等的内装饰物和家用防火材料等方面,具有更优异的防护功能和穿着舒适性。在实践中,人们发现有的阻燃纤维织物,虽然有阻燃效果,但在燃烧时烟雾很大,在火灾中有相当一部分人不是被烧死而是窒息死亡;有的阻燃织物燃烧时烟雾密度很低,但含有极毒化合物如HCN,因此研究阻燃纤维的烟雾成分从而研究其毒性具有重要的意义。     

阻燃剂二(5,5-二溴甲基-1,3,2-二氧六环磷酰)双酚A的合成

近年来,针对高分子材料易燃进行阻燃化处理,赋予其难燃性和抑烟性,对于有效阻止材料火灾事故发生和抑制火焰传播具有重要意义~([1-2]).磷、溴作为两类重要的阻燃元素,具有各自相应的阻燃机理,能够通过凝聚相和气相共同发挥阻燃作用,降低材料的燃烧性能.     

高效液相色谱-串联质谱法同时测定涂料产品中4种有机磷阻燃剂

<正>随着经济的发展和现代科学技术的进步,高分子合成材料被更为广泛和深入地应用于社会各个领域。但是这类材料的可燃性也很强,由此引起的火灾所带来的经济损失和对人身安全造成的伤害也日趋增强。根据欧盟非食品类危险产品快速预警系统的统计,火灾是通报最多的风险类别之一。如何改善高分子合成材料的防火性能,提高其着火点,增强产品的阻燃性能,减小火灾带来的危险性成为越来越多人关注的焦点。因此各国纷纷开展这类材料阻     

添加型磷腈类阻燃剂在高分子材料中的应用

添加型磷腈类阻燃剂具有热稳定性好、耐候性好、低烟、低毒、低添加量和吸潮性低等优点,在阻燃高分子材料领域得到广泛应用。综述了近些年来国内外添加型磷腈类阻燃剂在高分子材料中的应用研究进展,分析了磷腈阻燃剂阻燃高分子材料的研究现状,为新型磷腈类阻燃剂的研发提供参考。     

生物基高分子阻燃涂层的研究进展

生物基高分子由于具有绿色、环保、可再生和生物降解的特性,已经逐渐被应用到包装、汽车、电子电器等领域.部分生物基高分子(如壳聚糖、淀粉等)由于具有良好的成炭性而逐渐被应用于阻燃领域.这些生物基高分子主要通过添加和涂覆的方式被引入到材料中赋予材料良好的阻燃性能.本文综述了含有壳聚糖、淀粉、DNA以及植酸等生物基高分子材料阻燃涂层的研究进展,包括每种涂层的成分、涂覆方式、阻燃效果等,并简要介绍了几种生物基功能阻燃涂层.最后,对生物基阻燃涂层的发展趋势进行了展望.     

离子液体在阻燃领域的研究进展

离子液体作为一种新兴的绿色溶剂,具有低蒸气压、高热稳定性、良好的可设计性和非燃烧性等优点,在各个领域得到了广泛的应用。随着人们对消防安全的日益关注,研究和开发无(低)毒、低烟、绿色环保的阻燃材料逐渐成为阻燃领域的发展方向。本文简要综述了近几年来离子液体在阻燃领域的最新研究进展,重点介绍了离子液体在高分子基体中的阻燃机理和进展,同时也介绍了离子液体在棉织物及锂离子电池等材料中的阻燃应用,最后对其发展前景作了展望。     

磷腈化合物阻燃高分子材料研究进展

磷腈化合物是一类骨架由磷、氮单双键交替排列而成,侧基由有机基团组成的有机-无机化合物.由于其结构特殊、性能优异而被应用于防火阻燃、生物医用、高分子导体及液晶、燃料及催化剂等各种领域.磷腈有高含量的磷、氮元素,因而具有优异的阻燃性能.近年来,环三磷腈阻燃剂被越来越广泛地应用于高分子阻燃材料中.本文阐述了近10年来具有不同取代基的环三磷腈阻燃剂的合成及应用,重点介绍了其对环氧树脂、丙烯腈-丁二烯-苯乙烯共聚物(ABS)、聚烯烃、聚酯等高分子材料的阻燃性能及热稳定性的影响,并对其影响规律和阻燃机理进行了总结,对其应用前景进行了展望.     

木质素先进材料的研究进展

综述了木质素改善合成高分子材料的性能和制备光电材料、阻燃材料、电磁屏蔽材料等方面的研究进展。加强木质素结构和性能的基础研究,解决木质素反应活性偏低以及与基体相容性差的问题,将木质素的耐辐射、可生物降解、阻燃、电磁屏蔽等特异性能引入到传统合成高分子材料中,制备性能优异、功能多样的先进高分子材料,是木质素高值化利用的一个重要方向。     

纳米阻燃高分子材料:现状、问题及展望

纳米阻燃体系是一种新型的聚合物阻燃体系,被誉为阻燃技术的革命.极少量(≤5wt%)纳米阻燃剂的加入即能显著降低高分子材料燃烧时的热释放速率(HRR)和烟密度(SEA),延缓其燃烧过程,还能不同程度地提高材料的力学性能.本文总结了近年来国内外纳米阻燃领域的进展,介绍了本课题组在纳米阻燃方面所做的工作,探讨了纳米阻燃研究中存在的问题,并对其未来的发展进行了展望.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.