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1.
制备了PP(聚丙烯)/Al(OH)_3/Mg(OH)_2/硼酸锌和PP/Al(OH)_3/Mg(OH)_2阻燃复合材料,并测定了复合材料的氧指数(OI)、水平燃烧速度和烟密度。结果表明,OI随着阻燃剂质量分数的增加而升高,随着粒径的增大而降低;燃烧速度随着阻燃剂用量的增加而下降,随着粒径的增大先升后降;烟密度随着阻燃剂用量的增加而降低,随着粒径的增大而增大;添加硼酸锌后具有显著的抑烟效果。  相似文献   

2.
采用三氧化钼、钼酸铵、三氧化二锑、可膨胀石墨和硼酸锌作阻燃抑烟剂,分别按3种比例(5%、10%和15%)与膨胀阻燃体系(IFR)复配,制得水性膨胀型防火涂料。通过锥形量热仪研究了阻燃抑烟剂种类和用量对涂层燃烧性能的影响,并考察了其与IFR的协同性。结果表明,涂层生烟主要发生在着火之前,即烟气主要是裂解产物。三氧化钼或钼酸铵配合IFR会延迟点燃时间,与IFR质量比大于1∶1时可降低烟释放速率峰值(PSPR)。三氧化二锑或硼酸锌都不能降低热释放速率峰值(PHRR),且引入三氧化二锑还会明显增加PSPR。可膨胀石墨与IFR配比大于2∶3时,降低PHRR和PSPR的效果最好。这5种阻燃抑烟剂都能延迟热释放峰值时间和生烟速率峰值时间,其中硼酸锌的作用最明显。  相似文献   

3.
磷钼酸铵的制备及性能   总被引:1,自引:0,他引:1  
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。  相似文献   

4.
PP/Al(OH)3/Mg(OH)2复合材料阻燃性能研究   总被引:1,自引:0,他引:1  
制备了PP(聚丙烯)/Al(OH)3/Mg(OH)2/硼酸锌和PP/Al(OH)3/Mg(OH)2阻燃复合材料,并测定了复合材料的氧指数(OI)、水平燃烧速度和烟密度。结果表明,OI随着阻燃剂质量分数的增加而升高,随着粒径的增大而降低;燃烧速度随着阻燃剂用量的增加而下降,随着粒径的增大先升后降;烟密度随着阻燃剂用量的增加而降低,随着粒径的增大而增大;添加硼酸锌后具有显著的抑烟效果。  相似文献   

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利用氧指数(OI)测定仪和锥形量热仪(CONE)实验获得的氧指数、生烟量以及CO产生速率等参数,对环保型抑烟阻燃填料氢氧化镁、硼酸锌、MOO3以及其复配体系的烟毒释放进行了对比研究。结果表明:抑烟填料氢氧化镁具有较好的阻燃效果,硼酸锌、MOO3的加入能够明显降低材料燃烧时的烟毒释放;Mg(OH)2/MOO3复配体系能达到更好的阻燃抑烟协效作用,使烟毒参数进一步降低,从而制得低毒低烟环保阻燃涂料。  相似文献   

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针对ABS/PVC合金材料进行低烟、高阻燃改性研究.研究了十溴二苯乙烷/硼酸锌复合阻燃体系对ABS/PVC合金的阻燃作用以及八钼酸铵(AOM)复合体系的阻燃、抑烟作用.开发研制出氧指数40以上、烟密度SDR控制在30以内的高性能阻燃材料.  相似文献   

7.
超细Al(OH)3阻燃抑烟ABS性能与机理的研究   总被引:1,自引:0,他引:1  
王德花  李荣勋  刘光烨 《塑料》2008,37(1):78-81
文章研究了超细Al(OH)3对ABS材料阻燃、抑烟性能的影响,并对其机理进行了探讨.结果表明:Al(OH)3使ABS材料的热释放速率(HRR)、有效燃烧热(EHC)、质量损失速率(MLR)和生烟速率(SPR)显著降低;Al(OH)3是ABS良好的抑烟剂;Al(OH)3对ABS材料的阻燃抑烟以凝聚相机理和稀释机理为主.  相似文献   

8.
PBT的低烟阻燃性研究   总被引:2,自引:0,他引:2  
张保卫  翟燕  孙锡龙 《塑料工业》2003,31(6):43-44,50
研究了几种阻燃体系对PBT的阻燃抑烟效果,结果发现;用氢氧化镁(MH)和硼酸锌(ZB)与十溴联苯醚(DBDPO)—氧化锑或包覆红磷共同使用,可使燃烧过程的发烟量降低40%左右;聚苯醚(PPO)和一种磷酸酯阻燃剂配合使用;其阻燃抑烟作用及对力学性能的改善作用优于十溴联苯醚—氧化锑和包覆红磷体系。  相似文献   

9.
利用锥形量热仪(CONE)和热失重分析(TG)研究了化学膨胀阻燃剂(IFR)、氢氧化铝/红磷(Al(OH)3/P)及二者复合阻燃SBR的阻燃性能及热失重行为。结果表明,阻燃剂用量为40份,聚磷酸铵(APP)与季戊四醇(PER)质量比为3∶1时,SBR/APP/PER的热释放速率及生烟速率均大幅度下降,阻燃效果较好;Al(OH)3与P质量比为26∶14时,可有效降低SBR/Al(OH)3/P的热释放速率,但生烟速率较大;将APP/PER∶Al(OH)3/P=1∶1复配,SBR/IFR/Al(OH)3/P的热释放速率和生烟速率没有进一步改善,协同效应不明显。热失重研究表明,空气气氛下,试样SBR/IFR/Al(OH)3/P在300~500℃时,Al(OH)3/P反应使得SBR分解速度下降;在500~800℃时,APP与PER形成炭层,有效地起到隔热隔氧的作用,从而抑制炭黑的分解;两者复合使用,使阻燃SBR分解速度降低,热稳定性提高。  相似文献   

10.
将不同晶型的Bi2O3阻燃剂添加到软质PVC材料中,采用极限氧指数和烟密度评价Bi2O3对软质PVC的阻燃性能,并与常用的氧化锑(Sb2O3)和钼酸铵协同阻燃剂进行阻燃抑烟比较,结果表明:5%的β-Bi2O3阻燃剂添加至软质PVC时氧指数达35.5,烟密度为75%;而6%氧化锑与3%钼酸铵协同添加后软质PVC的氧指数达到35,烟密度为85.5%。SEM和TG/DSC表征Bi2O3在软质PVC中的分散和热分解特性,结果表明:β-Bi2O3的在PVC树脂中分散性优于α-Bi2O3,Bi2O3的加入使PVC前期热释放速率降低,后期分解释放小分子速度和数量均有所降低,增加了成碳率,从而提高PVC的氧指数和降低烟密度。  相似文献   

11.
Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.  相似文献   

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Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

14.
It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.  相似文献   

15.
2008~2009年世界塑料工业进展   总被引:4,自引:1,他引:3  
收集了2008年7月~2009年6月世界塑料工业的相关资料,介绍了2008~2009年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、环氧树脂、不饱和聚酯树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。  相似文献   

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Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

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