固体超强酸对膨胀阻燃聚乳酸燃烧性能的影响

采用固体超强酸(SSA)与膨胀阻燃剂复配对聚乳酸(PLA)进行阻燃处理,利用极限氧指数仪、垂直燃烧测定仪以及微型锥形量热仪研究SSA对PLA阻燃性能的影响,使用凝胶渗透色谱对阻燃PLA的分子量进行测试,通过热重分析仪研究阻燃PLA材料的热稳定性及残炭量,并利用扫描电子显微镜对其炭层形貌进行观察。分析结果表明,少量SSA的添加可以显著提高阻燃PLA材料的垂直燃烧级别,热稳定性和残炭量,可以降低材料的最大热释放速率。     

焦磷酸哌嗪协同次磷酸铝阻燃聚丙烯复合材料性能

为提高聚丙烯(PP)的阻燃性能,以焦磷酸哌嗪(PAPP)和次磷酸铝(AHP)为原料,通过熔融挤出的方式制备了不同质量比的PP复合材料,采用极限氧指数(LOI)、UL94垂直燃烧、热重分析(TG-DTG)、锥形量热(CONE)和扫描电子显微镜(SEM)等测试手段对PP复合材料热稳定性及阻燃抑烟性能进行分析,研究PAPP和AHP不同配比对阻燃性能的影响。结果表明,PAPP和AHP膨胀阻燃剂的加入大幅提升了PP复合材料的阻燃抑烟性能,当PAPP和AHP质量比为4∶1,总添加量为25%时,PP复合材料LOI达到31.5%,通过UL94垂直燃烧V-0级,800℃残炭率为23.16%,说明PAPP和AHP两者发挥了较好的协同阻燃作用。此外,其热释放速率(HRR)、总热释放量(THR)、烟释放速率(SPR)和总烟释放量(TSP)都得到大幅降低,SEM结果表明阻燃成分在PP复合材料表面形成了连续、致密的膨胀炭层,提升了材料的阻燃和抑烟性能。     

聚苯乙烯/次磷酸铝复合材料的制备及阻燃性能

采用熔融共混的方法制备了聚苯乙烯/次磷酸铝(PS/AHP)复合材料。采用热重分析测试研究了复合材料的热稳定性,通过极限氧指数、垂直燃烧和微型量热测试研究了复合材料的阻燃性能。研究表明:次磷酸铝(AHP)有效提高了PS/AHP复合材料的阻燃性能,当次磷酸铝添加量为20%时,复合材料可以达到UL-94 V-0级别,极限氧指数为24.0%;热重分析研究表明次磷酸铝的加入可以延缓聚苯乙烯分子链的降解,提高复合材料高温成炭率;微型量热(MCC)测试表明PS/AHP30与纯PS相比,其热释放速率峰值和总热释放分别下降40.5%和18.9%。     

HIPS/OMMT复合材料炭渣结构对阻燃性能的影响

采用熔融插层法制备了高抗冲聚苯乙烯/有机蒙脱土(HIPS/OMMT)和高抗冲聚苯乙烯/蒙脱土(HIPS/MMT)复合材料,并通过锥形量热仪评价了复合材料的阻燃性能;采用数码相机、扫描电镜(SEM)观察了燃烧残余物结构,对残余物结构进行了热重(TGA)分析。结果表明:OMMT的加入显著提高了复合材料以热释放速率表征的阻燃性能,而HIPS/MMT复合材料的阻燃性能提高不明显;HIPS/OMMT纳米复合材料燃烧热释放速率峰值时形成了皮窝复合炭渣结构,皮层组分主要为硅酸盐及部分难分解的碳质物质,热稳定性较高,窝层起膨胀炭层的作用,二者共同起阻燃作用。     

硅胶与膨胀型阻燃剂复配阻燃LGF/PP复合材料的性能研究

研究硅胶(SG)作为协效剂与IFR协同阻燃LGF/PP复合材料的性能。通过极限氧指数(LOI)、垂直燃烧(UL-94)、锥形量热仪(CONE)、热重分析法(TG)、扫描电子显微镜(SEM)、力学性能等测试表征LGF/PP/IFR/SG阻燃复合体系的性能。结果表明:当硅胶用量为2%时,阻燃复合材料的LOI为29.4%,且燃烧等级达到V-0级;CONE测试结果表明LGF/PP/IFR/SG阻燃复合材料的第一热释放速率峰值降低,而第二热释放速率峰消失;LGF/PP/IFR/SG阻燃复合材料具有较好的热稳定性,且产生致密均匀的炭层;并研究硅胶用量对复合材料力学性能的影响。     

聚乳酸/苯基次膦酸铝复合材料的制备及其阻燃性能研究

采用共沉淀法制备了苯基次膦酸铝(AlP)并对其进行表征。在此基础上,通过熔融共混法制备了一系列聚乳酸/苯基次膦酸铝（PLA/AlP）复合材料,采用热重分析（TG）、极限氧指数测试（LOI）、UL 94垂直燃烧测试、微型量热测试研究AlP对复合材料热稳定性、阻燃性能、燃烧性能的影响。结果表明,AlP可以有效提高PLA/AlP复合材料的阻燃性能, 当AlP含量为30 %（质量分数,下同）时,PLA/AlP30的极限氧指数达到25.6 %,并达到UL 94 为V-0级;AlP可以提高PLA/AlP复合材料初始分解温度和成炭性; PLA/AlP复合材料的热释放速率峰值和总热释放随着AlP添加量增大呈现先增高再下降的趋势。     

硅氧烷处理纳米层状硅酸盐对膨胀阻燃聚乳酸性能的影响

采用4种经过不同表面处理剂改性的有机层状硅酸盐（Clay）与膨胀型阻燃剂复配阻燃聚乳酸（PLA）。通过熔融共混的方法制备阻燃PLA纳米复合材料,并通过极限氧指数、垂直燃烧、锥形量热测试和热失重分析对材料阻燃性能和热稳定性进行了研究,通过扫描电子显微镜对残炭形貌进行了分析。结果表明,加入经硅氧烷表面处理的Clay的PLA具有最好的热稳定性和阻燃性能;与不加Clay的阻燃PLA复合材料相比,极限氧指数从30.6 %提高至34.2 %,并且通过垂直燃烧UL 94 V-0级别,热释放速率峰值从283 kW/m2下降至199 kW/m2,下降幅度为30 %;残炭形貌分析结果显示,加入硅氧烷表面处理之后的Clay能够使残炭更加完整致密,从而提高了材料的阻燃性能。     

不同协效剂对膨胀阻燃长玻纤增强聚丙烯体系的影响

将有机蒙脱土(OMMT)与水滑石(LDH)分别作为协效剂,与膨胀型阻燃剂(IFR)协同阻燃长玻纤增强聚丙烯(LGFPP)复合材料。利用氧指数(OI)、垂直燃烧测试(UL 94)、热失重分析(TGA)、扫描电子显微镜(SEM)和力学性能测试等手段研究了不同协效剂对LGFPP/IFR性能的影响。结果表明:OMMT与LDH均能在一定程度上提高其阻燃性能,当LDH含量为1%、OMMT含量为2%时,复合材料的阻燃性能最佳。而LGFPP/IFR/OMMT体系的阻燃性能更好,能够生成更加致密和稳定的炭层,并且表现出更好的热稳定性与力学性能。     

OMMT -卤-锑阻燃体系对 PA6／LGF 复合材料的影响

利用有机蒙脱土（ OMMT）协同溴代环氧树脂（ BER）、三氧化二锑（ Sb2 O3）通过熔融插层法制备OMMT-卤-锑阻燃长玻纤增强尼龙6复合材料（OMMT/FR/PA6/LGF）,通过极限氧指数（LOI）、垂直燃烧（UL-94）、锥形量热分析（CONE）、热失重分析（ TGA）、扫描电镜（ SEM）等方法研究了不同质量比的OMMT-卤-锑阻燃体系对OMMT/FR/PA6/LGF复合材料成炭、阻燃、燃烧、力学性能以及热稳定性的影响。结果表明,当OMMT添加量为2％, BER/Sb2 O3添加量为10％时,二者表现出优异的协同阻燃效应,不仅能促使OMMT/FR/PA6/LGF复合材料生成的炭层结构最为致密、均匀、连续,氧指数值最高且能保持FV-0级,还对复合材料的力学性能影响相对最小。     

聚乳酸/苯基次膦酸铈复合材料的制备及性能

采用简单方法合成苯基次膦酸铈(CeP),并将其作为阻燃剂加入聚乳酸(PLA)中,通过熔融共混技术制备聚乳酸/苯基次膦酸铈(PLA/CeP)复合材料。通过热重(TG)、极限氧指数(LOI)、UL-94垂直燃烧(UL-94)、微型量热(MCC)研究复合材料的热稳定性、阻燃性能和燃烧性能。通过阻燃测试发现,CeP能够提高复合材料阻燃性能,PLA/CeP20极限氧指数能达到24.3%并通过UL-94 V-2级别。热重分析的结果表明,CeP显著提高了PLA/CeP复合材料初始分解温度和成炭率。MCC测试结果表明,CeP能明显降低PLA/CeP复合材料火灾危险性。PLA/CeP20热释放速率峰值(PHRR)和总热释放(THR)分别为397 W/g和13.6 kJ/g,与纯聚乳酸相比,分别下降了13.9%和28.0%。因此,苯基次磷酸铈对聚乳酸具有良好的阻燃效果。     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

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.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008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、不饱和聚酯树脂、环氧树脂)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.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料,介绍了2005—2006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生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。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（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。