微波辅助阳离子瓜尔胶的合成研究

以瓜尔胶为原料,3-氯-2-羟丙基三甲基氯化铵为醚化剂,氢氧化钠为催化剂,异丙醇作为溶剂,利用微波辅助合成了阳离子瓜尔胶。结果表明,在瓜尔胶醚化过程中使用微波辅助,反应时间是传统阳离子瓜尔胶合成方法的1/6,提高了反应效率。最佳反应条件为:溶剂选用85%异丙醇,微波功率300 W,微波辐射时间为30 min,反应温度40℃,醚化剂与瓜尔胶的物质的量比为0.25,碱与瓜尔胶的物质的量比为0.20。产物水溶性很好,可与表面活性剂复配。     

C-GG型改性瓜胶的制备

天然瓜尔胶粉与醚化剂在乙醇溶液中反应,制备C-GG改性瓜尔胶,考察了反应物料比、反应时间、反应温度等对产品性能的影响。结果表明,合成C-GG改性瓜尔胶的最佳制备条件为:瓜尔胶粉:氢氧化钠:3-氯-2-羟丙基三甲基氯化铵为1:0.2:0.06,反应温度为70℃,反应时间为3 h。在最佳反应条件下,得到产品的性能符合标准,粘度达到3 650 mPa.s,取代度为0.224。     

阳离子田菁胶的合成及性能研究

以田菁胶(SG)为原料,3-氯-2-羟丙基三甲基氯化铵(CHPAC)为醚化剂,氢氧化钠为催化剂,异丙醇水溶液为分散剂,合成阳离子田菁胶。讨论了影响阳离子田菁胶取代度的主要因素,得出较优的合成条件为:n(NaOH)/n(SG)=0.4,n(CHPAC)/n(SG)=0.5,碱化温度20℃,碱化时间50 min,醚化温度50℃,醚化时间4 h,制得阳离子田菁胶的取代度为0.45。将阳离子田菁胶添加到洗发水中进行梳理性测试,结果表明其具有较好的调理性能。     

阳离子瓜尔胶粘度对头发梳理性的影响

以瓜尔胶为原料,3-氯-2-羟丙基三甲基氯化铵为醚化剂,氢氧化钠为催化剂,乙醇为溶剂,制备了阳离子瓜尔胶。利用头发梳理仪测定了洗发水中添加阳离子瓜尔胶前后,头发之间的摩擦力变化,考察了阳离子瓜尔胶对头发干、湿梳理性的影响,得出阳离子瓜尔胶能明显改善头发的梳理性:3300mPa.S以上粘度的阳离子瓜尔胶显示效果较佳。     

粘胶纤维的阳离子改性及吸附性能研究

以粘胶纤维为原料,2,3-环氧丙基三甲基氯化铵为醚化剂,氢氧化钠为催化剂,合成了阳离子改性粘胶纤维,采用正交试验法和单因素实验考察了氢氧化钠用量、反应温度、反应时间对阳离子改性粘胶纤维吸附甲基橙性能和氮含量的影响,得出了最佳反应工艺条件为:反应温度为70℃,反应时间为1h,醚化剂的加入量为粘胶纤维的30%,碱液的加入量为0.72g,加入量为粘胶纤维的1%。采用紫外分光光度计测定了阳离子改性粘胶纤维的吸附性能,实验结果表明:阳离子改性粘胶纤维对染料的吸附具有选择性,对甲基橙溶液的吸附能力明显优于次甲基蓝溶液。     

一种合成季铵盐阳离子瓜尔胶的新方法

以瓜尔胶胚乳片为原料,3-氯-2-羟丙基三甲基氯化铵为阳离子醚化剂,在水媒介中合成阳离子瓜尔胶。利用FTIR光谱对阳离子瓜尔胶进行结构表征。通过正交试验研究碱的用量、阳离子醚化剂用量、反应温度、反应时间对产物的取代度的影响。结果表明,在胚乳片为100 g,NaOH为12 g,3-氯-2-羟丙基三甲基氯化铵为50 g,45~50℃反应60 min条件下,可以得到取代度0.08的季铵盐瓜尔胶,其中碱量和阳离子醚化剂用量对产物取代度影响较大。     

BCl_3对1-丁烯聚合用Ziegler-Natta催化剂的改性研究

以BCl3溶液对用于1-丁烯聚合的Ziegler-Natta催化剂进行改性,通过正交试验考察了n(B)/n(Ti)、反应温度和反应时间对催化剂性能的影响,并研究了各因素对Ti含量、B含量、催化剂活性和聚合物等规指数的影响。BCl3改性催化剂的最佳条件:n(B)/n(Ti)为1,反应温度为60℃,反应时间为2h。改性后的催化剂活性相对未改性时提高了1.4倍。各因素对Ti含量、催化剂活性和聚合物等规指数的影响主次顺序为反应温度,n(B)/n(Ti),反应时间;对B含量的影响主次顺序为反应温度,反应时间,n(B)/n(Ti)。     

玉米羧甲基淀粉崩解剂的合成及性能改进

采用玉米淀粉为原料,以环氧氯丙烷为交联剂、氢氧化钠和氯化铵为复合催化剂、氯乙酸为醚化剂复合变性合成用作药片崩解剂的羧甲基淀粉,探讨了各种反应条件对淀粉的取代度、膨润性能及反应效率的影响,反应效率提高,反应时间大大缩短。原料最佳配比:n(脱水葡萄糖单元)∶n(环氧氯丙烷)∶n(氯乙酸)∶n(氢氧化钠)=1∶0.4∶0.6∶1.2,反应温度60°C左右,反应时间1～2h。     

天然瓜尔胶改性研究

研究了阳离子瓜尔胶的制备方法、影响因素。通过对反应时间,反应温度,反应中氢氧化钠用量及溶剂等各因素的研究,得出最佳工艺条件:当瓜尔胶的用量为10.0 g时,CTA用量为1.50 g,氢氧化钠与CTA摩尔比为2.3左右,反应温度控制在80℃,反应时间为9.0 h,所得产物的取代度为0.062,反应效率为41.5%。     

两性离子型瓜尔胶的合成研究

以瓜尔胶(GG)为原料、3-氯-2-羟丙基二甲铵基乙酸盐(CCDH)为两性醚化剂,在碱催化剂作用下半干法合成了不同取代度的ZGG,并通过IR对CCDH和ZGG进行了表征。同时考察了体系中碱用量、反应温度、反应时间对产品取代度的影响。结果表明,当瓜尔胶用量为8 g,CCDH为4 g,NaOH为0.06 g,温度为65℃,反应时间为5 h,取代度为0.544。     

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。