微胶囊化聚磷酸铵的制备及其性能

以聚乙二醇(PEG)改性聚氨酯(PUR)为囊材对聚磷酸铵(APP)进行包覆,制备了"三源一体"的膨胀型阻燃剂(MAPP)。通过用傅立叶变换红外光谱(FTIR)、扫描电子显微镜(SEM)、X射线能谱(EDS)和X射线衍射(XRD)等手段对微胶囊的核壳结构进行表征,采用溶解度测试、水接触角测试研究了季戊四醇(PER)和PEG的配比对微胶囊包覆效果的影响。结果表明,与未包覆的APP相比,MAPP上出现了PUR的特征峰;SEM明显观察到MAPP表面变得粗糙,蜂窝状结构出现;EDS结果显示APP和MAPP具有不同的表面元素含量;XRD峰强度明显减弱,表明改性PUR成功包覆在APP粒子表面;水溶解度和接触角的变化可知,MAPP的水溶解度和表面极性均有所下降,当PER/PEG的物质的量之比为1/1时,包覆效果最佳,此时的溶解度为0.400 g/100 m L H2O,水接触角为86.1°。     

聚磷酸铵表面疏水改性研究

通过自制乳液吸附在聚磷酸铵(APP)表面,实现APP表面疏水改性。利用扫描电镜、傅立叶变换红外光谱仪以及接触角测量仪表征了改性前后APP的表观形貌、化学结构和疏水性能。对该吸附过程的影响因素进行了分析。结果表明:常温下,醇水比为2∶8、pH为7. 0为宜;改性聚磷酸铵(MAPP)的疏水性能与乳液吸附量相关,当吸附量达232. 0 mg/g,其接触角由改性前的8. 69°增至103. 11°,此后吸附量再增加,接触角无明显变化。     

微胶囊化多聚磷酸铵的耐水性及其在聚丙烯中的阻燃性能

采用三聚氰胺-甲醛树脂(MF) 为囊材,以多聚磷酸铵（APP）为芯材制得微胶囊化多聚磷酸铵（MAPP）。耐水性及膨胀度试验表明,MAPP为膨胀型阻燃剂,APP/MF =3/1 (质量比,下同)时,MAPP在50 ℃时在水中的溶解度为0.052 g/100 mL,比APP减低了78 ％;膨胀度达到78.6 ㎝3/g。热分析表明,聚丙烯（PP）/MAPP比PP/APP的热降解速度加快,但释热量减小。由于形成蓬松多孔膨胀炭层,PP/MAPP比PP/APP的阻燃性能更佳,PP/MAPP=70/30时,其氧指数增到30.6 %。     

聚硅氧烷包覆改性聚磷酸铵及其阻燃聚乙烯性能的研究

分别以二甲基二乙氧基硅烷（DMDES）、甲基三乙氧基硅烷（MTES）、苯基三甲氧基硅烷（PTMS）3种硅氧烷与正硅酸四乙酯（TEOS）共同作为前驱体,采用溶胶-凝胶工艺对聚磷酸铵（APP）进行微胶囊化包覆改性,分别制备得到改性聚磷酸铵APP/DMDES、APP/MTES和APP/PTMS,以改善其阻燃性、热稳定性和疏水性。通过傅里叶红外光谱、水接触角、扫描电子显微镜、能谱仪以及热失重分析等测试与表征手段,对3种不同聚硅氧烷包覆改性聚磷酸铵（MAPP）进行了对比研究,并研究了MAPP对低密度聚乙烯（PE-LD）阻燃性能、力学性能和热性能的影响。结果表明,在合适的工艺条件下,均可以制备得到聚硅氧烷包覆改性聚磷酸铵;较改性前的APP,改性聚磷酸铵的疏水性和热稳定性均显著提高;在PE-LD/APP/PTMS/季戊四醇（PER）/三聚氰胺（MEL）的质量比为65/18.7/11.7/4.6时,PELD复合材料的综合性能最好,极限氧指数为26.6%,高于包覆前APP的23.3%,达到UL 94 V-0级别,且拉伸性能最高,为12.84 MPa。     

MAPP阻燃EVA泡沫复合材料的制备及其性能

利用乙二胺(EDA)对聚磷酸铵(APP)进行改性,得到聚磷酸铵衍生物(MAPP)。采用MAPP、石墨(EG)和木粉(MF)复配的方式得到膨胀性阻燃剂,并与EVA复合得到泡沫复合材料。采用FT-IR、XRD、1H NMR表征接枝效果,利用LOI和UL-94测试仪、锥形量热仪(CONE)、TG及SEM等分析材料的阻燃性能、残炭的形态及力学性能。结果表明:EDA已成功接枝在APP上,所形成的MAPP能够有效提高复合发泡材料的阻燃性能、减少热释放量;MAPP/EVA复合发泡材料的残炭层更加致密和完整,能够有效起到隔热、隔氧的作用;并且MAPP能够提高材料的耐水性及与EVA基体的相容性。当MAPP添加量为20%时,体系的LOI可达27.6%,且UL-94为V-0级别,拉伸强度、断裂伸长率分别可达1.282 MPa、236.40%,阻燃材料的综合性能达到最优。     

微胶囊聚磷酸铵的制备及阻燃环氧树脂的性能研究

采用三聚氰胺甲醛树脂预聚物通过原位聚合法制备了微胶囊聚磷酸铵阻燃剂(MAPP),利用扫描电镜观察到MAPP颗粒表面包覆了一层树脂。采用热重分析法、垂直燃烧法和氧指数法研究了聚磷酸铵(APP)和MAPP阻燃环氧树脂材料的热性能及阻燃性能。结果表明:与APP相比,MAPP阻燃环氧树脂的最大失质量温度、残炭量以及阻燃性能均显著提高。添加10%APP或MAPP的环氧树脂材料的氧指数均大于27.0%,阻燃性能均达到UL 94 V-0级,且MAPP样条燃烧后可形成膨胀炭层。相比于APP,MAPP阻燃材料的力学强度均有所改善,当阻燃剂填充10%时材料的拉伸强度从32.6 MPa提高到35.7 MPa,冲击强度从10.8 kJ/m2提高到11.6 kJ/m2,均高于纯环氧树脂材料的力学强度。     

微胶囊化聚磷酸铵及其在聚丙烯中的阻燃性能

采用聚氨酯(PU)为囊材,聚磷酸铵(APP)为芯材制备了微胶囊阻燃剂(MAPP)。通过溶解度测试、傅里叶红外光谱(FTIR)和扫描电镜(SEM)对微胶囊的核壳结构进行了表征。采用氧指数法、垂直燃烧法和SEM考察了APP和MAPP对PP的阻燃效果。结果表明:与APP相比,MAPP溶解度明显下降,FITR和SEM测试表明APP被PU包覆了;通过SEM观察MAPP/PP体系在燃烧后能生成更加连续和致密的炭层,有效地保护了炭层下的材料。在聚丙烯复合材料中,当APP和MAPP添加量相同时(30%),LOI值从22.0%提高到32.0%,且UL-94达到V-0级。     

改性剂对废弃玻璃钢/聚丙烯复合材料性能的影响

实验采用熔融共混-模压法制备了废弃玻璃钢(WGFRP)/聚丙烯(PP)复合材料。研究了硅烷偶联剂KH550表面改性WGFRP、改性聚丙烯(MAPP)添加量以及乙烯-辛烯共聚物(POE)的使用对WGFRP/PP复合材料性能的影响。实验结果表明,KH-550表面改性WGFRP能使复合材料性能小幅度提高,MAPP可使复合材料的拉伸和弯曲强度分别提高28.63%、20.13%,添加POE后,复合材料的断裂伸长率和冲击强度增幅分别达到152.36%、45.43%。扫描电镜图片显示,多种改性剂的加入有效改善了WGFRP和PP的界面粘合程度,宏观表现为复合材料性能提高。     

苯基聚硅氧烷微胶囊化聚磷酸铵的制备及其在PP中阻燃性能研究

采用苯基三甲氧基硅烷为前驱体,通过溶胶凝胶法制备出苯基聚硅氧烷微胶囊化聚磷酸铵（MAPP）。将MAPP作为阻燃剂,季戊四醇（PER）作为成炭剂,制备阻燃聚丙烯（PP）。用傅里叶红外光谱、扫描电子显微镜、能谱仪及热重分析仪对MAPP进行表征。结果表明,聚磷酸铵（APP）被苯基聚硅氧烷成功包覆;较之APP,MAPP的热稳定性和疏水性显著提高;MAPP的阻燃性能优于APP,PP/MAPP/PER复合材料达到V-0级别;阻燃剂及成炭剂的加入对PP的结晶行为有促进作用。     

MAPP阻燃EVA泡沫复合材料的制备及其性能

利用乙二胺（EDA）对聚磷酸铵（APP）进行改性,得到聚磷酸铵衍生物（MAPP）。采用MAPP、石墨（EG）和木粉（MF）复配的方式得到膨胀性阻燃剂,并与EVA复合得到泡沫复合材料。采用FT-IR、XRD、¹H NMR表征接枝效果,利用LOI和UL-94测试仪、锥形量热仪（CONE）、TG及SEM等分析材料的阻燃性能、残炭的形态及力学性能。结果表明：EDA已成功接枝在APP上,所形成的MAPP能够有效提高复合发泡材料的阻燃性能、减少热释放量;MAPP/EVA复合发泡材料的残炭层更加致密和完整,能够有效起到隔热、隔氧的作用;并且MAPP能够提高材料的耐水性及与EVA基体的相容性。当MAPP添加量为20%时,体系的LOI可达27.6%,且UL-94为V-0级别,拉伸强度、断裂伸长率分别可达1.282 MPa、236.40%,阻燃材料的综合性能达到最优。     

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.     

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.     

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。