聚己内酯丙交酯共聚物的制备及表征

以己内酯和D,L-丙交酯为原料,辛酸亚锡为催化剂,在减压条件下开环聚合己内酯丙交酯无规共聚物。分别利用红外光谱、核磁共振技术对产物进行结构分析,利用差示扫描量热仪及热重分析仪对产物进行热性能分析。结果表明:成功合成了目标产物,投料比接近共聚物组成比例,共聚物的热降解分2步进行。     

树枝状聚酯—聚L-赖氨酸（Z）两嵌段共聚物的合成

由2,2-二羟甲基丙酸与2,2-二甲氧基丙烷经过逐级醇酸缩合、催化加氢和端氨基化后得到端基为氨基的树枝状聚酯分子G3-C3H9N2,以此为引发剂引发ω苄氧羰基L-赖氨酸-N-羧酸酐（ω-Z—L—lysine—NCA）开环聚合得到树枝状聚酯-聚L-赖氨酸（Z）两嵌段共聚物。采用^1H—NMR、IR、GPC方法对产物进行表征。结果表明：G3-C3H9N2能有效引发NCA开环聚合,共聚物的分子量可以通过调节单体引发剂比例来控制,所得产物具有较窄的分子量分布系数。     

乙交酯-己内酯共聚物的功能化研究

以乙交酯和己内酯为起始原料,经开环聚合、上保护基团、脱保护基团三步反应合成了新型功能化乙交酯-己内酯共聚物,端氨基乙交酯-己内酯共聚物PGCL-NH2。采用红外光谱、DSC以及TGA对合成的共聚物及其中间产物进行了表征和分析。结果表明,此合成工艺路线是成功的,其为制备端氨基聚酯共聚物开辟了一条新途径。     

乙交酯-己内酯共聚物的功能化研究

以乙交酯和己内酯为起始原料,经开环聚合、上保护基团、脱保护基团三步反应合成了新型功能化乙交酯-己内酯共聚物,端氨基乙交酯-己内酯共聚物PGCL-NH2。采用红外光谱、DSC以及TGA对合成的共聚物及其中间产物进行了表征和分析。结果表明,此合成工艺路线是成功的,其为制备端氨基聚酯共聚物开辟了一条新途径。     

乙二醇-1,6-己二酸-1,6-己二胺型聚酯酰胺的合成及表征

以乙二醇、1,6-己二酸和1,6-己二胺为主要原料,合成了一系列不同胺含量的共聚物。用红外光谱分析聚合产物的结构,以差示扫描量热仪、显微熔点测定仪及热重分析仪测试其热性能,并对其薄膜进行拉伸测试。结果表明,加入己二胺共聚得到的产物属于聚酯酰胺。随着己二胺掺量的增多,聚酯酰胺的熔点和热稳定性一直增大,而其断裂伸长率先增大后减小。     

新型聚乙烯-g-聚乳酸接枝共聚物的合成与表征

报道了一类主链为聚乙烯(PE)共聚物,侧链为生物基聚乳酸(PLA)的新型接枝共聚物及其制备方法,并对接枝共聚物结构与性能进行了深入的表征。采用配位聚合与开环聚合相结合的方法,以羟基功能化的聚乙烯共聚物为主链,通过羟基引发L-丙交酯(L-LA)的开环聚合,从而获得聚乙烯-g-PLA接枝共聚物。通过控制单体比例和反应条件,可同时实现接枝共聚物的主链结构以及侧链结构调控。结果表明,少量PLA接枝链的引入可在不明显降低拉伸强度的情况下,有效地改善接枝共聚物的断裂伸长率。热性能表征发现侧链PLA的引入限制了主链聚乙烯的结晶,造成了接枝共聚物结晶温度以及熔点的下降。该接枝共聚物展现出了可用于PLA等生物基聚酯材料的增韧改性或共混增容剂的应用潜力,也为此类接枝共聚物的合成与性能调控提供了重要的参考。     

开环易位聚合法制备功能化聚烯烃研究进展

综述了近年来利用开环易位聚合法制备功能化聚烯烃的研究进展,包括无规共聚物、嵌段共聚物和接枝共聚物的制备及其相关性能的研究。开环易位聚合催化剂的耐受性较好,可用于催化多种单体的聚合,从而制备含有多种官能团的聚烯烃,所制聚烯烃具有较为优异的力学性能、表面性能和热性能。通过引入特定功能化取代基还可以赋予聚烯烃优异的光学性能、介电性能、生物性能等。     

合成羟基功能化聚酯的研究进展

概括介绍了合成羟基功能化聚酯的几种方法,主要有线形缩聚法、开环聚合法、羟基保护和脱保护法、在聚酯的侧链中引入羟基法和酶催化聚合法。对每种合成方法的特点进行了评述：线形缩聚法的原料来源丰富、价格便宜,但是工艺条件苛刻;开环聚合法的反应时间短、产物性能较好,但是分离和回收工艺成本高;羟基保护和脱保护法的实验步骤多、产物产率低;在聚酯侧链中引入羟基法的原料不易制备、工艺成本高;酶催化聚合法的反应条件温和,但是酶的价格高、导致工艺成本高。     

环戊烯-双环戊二烯共聚的新型橡胶——Ⅱ.共聚物的结构分析和性能的研究

本文借助溶解实验法和测定聚合物的玻璃化温度,证明了环戊烯与双环戊二烯在WCl_(?)-AlEt_2I-四氯苯酚催化体系中的聚合产物是共聚物;用红外光谱法研究论证了双环戊二烯的开环聚合历程及其共聚物分子结构;测定了共聚物的生胶,混炼胶和硫化胶的性能。     

“活性”原子转移自由基聚合向活性正离子开环聚合转化制备苯乙烯-2-甲基-2-噁唑啉嵌段共聚物(英文)

以苯乙烯的ATRP聚合制备含卤端基的聚苯乙烯，再以此含卤端基的聚苯乙烯引发2－甲基－2－唑啉的正离子开环聚合，合成了苯乙烯与2－甲基－2－唑啉嵌段共聚物，并用IR，GPC对开环产物进行了表征。     

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.     

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.     

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.     

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。     

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.