改性废聚氨酯制备高分子膨胀型阻燃剂

以废聚氨酯(PU)、三氯氧磷(POCl3)等为原料合成了二氯磷酰化聚氨酯(PDP),再将PDP与三聚氰胺(MEL)等反应,制备了高分子膨胀型改性聚氨酯阻燃剂(MPU)。通过红外光谱(FTIR)分析、扫描电镜-能谱分析(SEM-EDS)、热重分析(TGA)等手段对产物进行了表征。将所得MPU用于环氧树脂(EP)的阻燃,并采用极限氧指数法(LOI)、垂直燃烧法(VBT)等方法检测了EP/MPU复合材料的阻燃性能。结果表明:当以1,4-二氧六环为溶剂、PU浓度为20 g/L、POCl3浓度为400 g/L、反应温度为80℃、反应时间为13 h时,PDP的P含量可达到19.6%;当MPU含量为30%时,EP/MPU复合材料的LOI值为28%,阻燃等级可达到UL 94V-0级。     

IFR阻燃ABS体系燃烧性能的研究

以均匀设计数学模型为基础,利用计算机辅助系统(CAD),研究膨胀阻燃剂(IFR)三组分,聚磷酸铵(APP)、季戊四醇(PER)、三聚氰胺(MEL)对ABS阻燃性能的影响,体系中IFR质量分数为30％.结果表明:MEL用量为30份,APP/PER的质量比约为2/1时,垂直燃烧(UL-94)难燃级别可以达到Ⅴ-0级;固定APP/PER的质量比为2/1,随着MEL用量的增加,极限氧指数(LOI)降低,UL-94垂直燃烧时间增大;通过实验观察,提出“T型头”和“火焰簇”两种燃烧现象,并利用IFR阻燃机理,解释了LOI与UL-94形成竞争关系的原因.     

4,6-二氯嘧啶清洁合成工艺

报道了一种清洁合成4,6-二氯嘧啶(DCP)工艺.首先,由甲酰胺、丙二酸二甲酯和甲醇钠制备4,6-二羟基嘧啶(DHP).当n(丙二酸二甲酯):n(甲酰胺):n(甲醇钠)=1:4:4,反应温度为60℃,反应时间2 h时,DHP的收率可达90.4％.然后,DHP与POCl3在60℃下反应2 h获得DCP.此反应的最佳条件为:5-乙基-2-甲基吡啶为缚酸剂,质量分数45％的1,2-二氯乙烷作溶剂,n(DHP):n(POCl3):n(5-乙基-2-甲基吡啶)=1:2.2:1.8,DCP的收率高达94.6％.确定以氢氧化钙处理氯化废水的工艺,缚酸剂的回收率高达90％以上,磷酸钙与氯化钙能有效分离,成功解决DCP生产过程中的三废问题,实现了DCP清洁生产的目标.     

MEL/MCM-48微介孔复合分子筛的制备与性能研究

按1SiO2∶ 0.35TBAOH∶ 25H2O的摩尔比,170℃水热晶化48 h得到微孔分子筛MEL,再按n(SiO2)∶ n(CTAB)∶n(H2O)∶n(NaOH)=1∶0.45∶60∶0.48的摩尔比,配成MCM-48的悬浮液,将合成的MEL加入MCM-48的溶液中,80℃水热晶化96h,制备出MEL/MCM-48微介孔复合分子筛,其结构和形貌采用XRD、TEM等手段对其进行了表征.考察了这种复合分子筛的投加量、pH值、吸附时间等因素对阳离子红X-5GN模拟染料废水吸附性能的影响.MEL/MCM-48微介孔复合分子筛的投加量为1 g/L、阳离子红X-5GN染料废水浓度为20 mg/L,溶液为中性、振荡时间为60 min,温度为50℃时吸附效果最好,脱色率以达到了97.8％,吸附动力学曲线不符合一级反应模型(Lagergren一级速率方程),但用二级反应模型(McKay二级速率方程)来描述可以得到很好的相关性.     

一种新型P-N-Cl协效阻燃剂的合成及其在热固性树脂中的应用

以邻苯二胺、顺丁烯二酸和三氯氧磷为原料,以三乙胺作为缚酸催化剂,合成了新型P-N-Cl协效苯并咪唑型阻燃剂。利用元素分析、FTIR及1H NMR波谱对中间体和阻燃剂分子结构进行了表征。通过单因素实验考察了反应时间、反应温度及原料物质的量比nPOCl3∶n中间体(I)等主要反应条件对P-N-Cl协效阻燃剂收率的影响,发现在t=8 h,T=75℃以及nPOCl3∶n中间体(I)=2.25的优化条件下,阻燃剂最大收率为73.6%。通过极限氧指数(LOI)测定,考察了该P-N-Cl协效阻燃剂对191型不饱和树脂和环氧树脂E-44的阻燃效果,结果发现在阻燃剂质量分数12%时二者的LOI可分别达到33.7%和32.3%,表明其具有良好的阻燃性能和潜在应用前景。     

阻燃剂季戊四醇双磷酸酯二磷酰氯缩三聚氰胺的合成及表征

以季戊四醇、氧氯化磷、三聚氰胺为原料,两步合成了阻燃剂季戊四醇双磷酸酯二磷酰氯缩三聚氰胺,通过红外光谱及元素分析对其结构进行了鉴定。最佳合成工艺条件为:第一步,n[C(CH2OH)4]∶n(POCl3)=1∶2.2,反应7 h,反应温度80℃,收率为88%;第二步,n(中间体)∶n(C3N6H6)=1∶2,反应0.5 h,反应温度80℃,收率98%。     

MCA对环氧树脂阻燃性能的研究

使用溶液共混的方法制备了w[三聚氰胺氰尿酸盐(MCA)]=0、1%、3%、5%、7%(相对环氧树脂材料总质量而言)的环氧树脂(EP)材料,并使用氧指数仪、锥形量热仪、热重-红外联用仪进行性能检测。研究结果表明:MCA的加入能够提高EP材料的阻燃性,当w(MCA)=5%的环氧树脂材料具有较佳阻燃性能;较之纯EP材料,极限氧指数(LOI)的值提高了6.5%,最大热释放速率(PHRR)下降了29.03%,点燃时间延后39.86%,质量损失速率(MLR)峰值降低22.22%,最大一氧化碳产生率(COP)降低了35.06%,且此速率出现的时间延后了29.74%。MCA分解后释放各种不燃气体,使得燃烧区含氧量下降,三聚氰胺等大分子分解和水分子蒸发都需要吸收热量,进而提升了环氧树脂的阻燃性。     

1-氨基乙叉-1,1-二膦酸及其协效组合物对聚丙烯阻燃性能的影响

制备了白色粉末状的有机膦酸—1-氨基乙叉-1,1-二膦酸(AEDP)。将AEDP及其与三聚氰胺(MEL)、季戊四醇(PER)复配得到的协效组合物作为阻燃剂对聚丙烯(PP)进行阻燃,考察了AEDP及其协效组合物对PP阻燃性能的影响。结果表明:AEDP及其协效组合物AEDP/MEL/PER均能显著提高PP的阻燃性能。其中当AEDP作为单组分阻燃剂且用量为27%时,阻燃试样(PP-Ⅱ)通过UL 94V-0测试,其极限氧指数(LOI)值达到24.4%。当AEDP/MEL/PER协效阻燃剂(复配比为12:8:5)的用量为25%时,阻燃试样(PP-Ⅶ)通过UL94V-0测试,其LOI值达到29.2%。锥形量热分析结果显示,纯PP、PP-Ⅱ和PP-Ⅶ的峰值热释放速率分别为779、322和252 kW/m~2。其中,PP-Ⅱ在锥形量热测试后形成了致密且厚实的残余物,热分解过程中形成的这种致密残余物层可通过固相隔绝原理对材料起到阻燃作用。     

环氧树脂改性高度支化水性聚氨酯的合成与性能研究

用甲苯-2,4-二异氰酸酯(TDI)、聚碳酸酯二醇(PCDL)、二羟甲基丙酸(DMPA)等为原料,制备了线性水性聚氨酯(LWPU,A2),并通过"A2+B3"的方式,将其滴加到聚醚胺(T403)的四氢呋喃–异丙醇(THF–IPA)溶液(B3)中,合成出端氨基高度支化水性聚氨酯(HBWPU)。用核磁共振仪表征了HBWPU的结构,证实合成成功。考察了TDI、DMPA和T403的用量对HBWPU的乳液粒径、外观和力学性能的影响,得到最优配方为:n(NCO)∶n(OH)=1.3,w(DMPA)=6.0%,n(B3)∶n(A2)=0.8。以双酚A型环氧树脂(EP)改性最优配方所得的HBWPU,用红外光谱研究了产物HBWPU/EP的结构,通过热重分析(TGA)和应力-应变曲线探讨了EP用量对其热稳定性和力学性能的影响。结果表明,引入EP明显提升了HBWPU的热稳定性及力学性能。当m(EP)∶m(HBWPU)=0.2,HBWPU/EP的拉伸强度达38.30 MPa,断裂伸长率为252%。但当EP用量过多,拉伸强度反而下降。     

阻燃剂2,4,6-三(2,4,6-三溴苯氧基)-1,3,5-三嗪的合成及工业试验研究

对阻燃剂2,4,6-三(2,4,6-三溴苯氧基)-1,3,5-三嗪的相转移催化合成工艺进行了改进,完成了工业试验研究。通过向2,4,6-三溴苯酚、三聚氯氰的溶液中滴加氢氧化钠水溶液的方式进行相转移催化合成,考察了有机溶剂、物料摩尔比、反应温度、反应时间对反应的影响。用正交实验确定了最佳物料配比n(2,4,6-三溴苯酚)∶n(氢氧化钠)∶n(催化剂)∶n(三聚氯氰)=3.05∶3.05∶0.05∶1,经工艺优化,产品收率达到96.6%,用IR分析了产品结构。工业试验在3 m3反应釜中进行,消耗定额为:2,4,6-三溴苯酚800 kg、三聚氯氰146 kg、氢氧化钠96.4kg、二氯甲烷1 400 kg、乙醇1 000 kg。溶剂二氯甲烷和乙醇回收率达到90%以上,重复使用10次后,工业试验产品收率仍可达到95%。工业试验产品经热重分析,温度达到320℃时,失重为1%,在H IPS中应用结果表明,其机械性能、热性能和阻燃性能完全满足出口阻燃H IPS的技术指标要求。     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

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.     

Sapindaceae,cyanolipids, and bugs

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.     

2008～2009年世界塑料工业进展

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。     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。     

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.