非离子型石蜡乳液的制备

以58#石蜡和复配乳化剂为原料,采用剂在油中法,制备了非离子石蜡乳液。考察了乳化剂类型、乳化剂用量、乳化温度、乳化时间、搅拌速度对石蜡乳液性能的影响。确定了最佳乳化工艺条件：复配乳化剂用量9%,乳化温度85℃,乳化时间40 min,搅拌速度500 r/min。成品含固量约为30%,具有良好的稳定性和分散性。     

非离子型蜡乳液的制备工艺

选用复配Ⅰ型乳化剂作为石蜡的乳化剂,考察乳化剂用量、乳化温度、乳化时间、搅拌速度等因素对蜡乳液性能的影响。通过实验确定了制备非离子型蜡乳液的最佳工艺条件:复配Ⅰ型乳化剂用量为蜡乳液用量的10%,乳化温度为85℃,乳化时间为45min,搅拌速度为1000r/min。在此条件下,可制备得到稳定的平均粒径为0.381um,分散度为0.373的石蜡乳液。     

具有良好稳定性的石蜡乳液的制备及改进

选用Span80、Tween80为石蜡复配乳化剂,采用O-D乳化法与PIT法相结合研究了乳化剂HLB值、乳化剂用量、乳化水加入方式及用量、乳化时间、乳化温度、搅拌方式及搅拌速度对石蜡乳液制备的影响。结果表明,适宜的乳化工艺条件为:复合乳化剂的HLB为10.5,复合乳化剂的用量(M乳化剂/M石蜡)为30%,乳化水用量(M水/M石蜡)为2.5,乳化时间30 min,乳化温度75℃,搅拌速度1 000 r/min。在该条件下可制得具有良好稳定性和分散性的石蜡乳液,粒径单分散性也较好。     

切片石蜡乳液的制备

石蜡一直存在难乳化、乳液稳定性差等问题。研究了以切片石蜡为原料,采用种子乳液聚合法,选择复配型乳化剂;讨论了乳化剂用量,乳化时间,乳化温度以及搅拌速度等因素对石蜡乳液稳定性和分散性的影响。结果表明:在乳化剂用量为乳液总量的10%,乳化时间为70 m in,乳化温度控制在(85±5)℃,搅拌速度为1500 r/m in的反应条件下,可制备出稳定的切片石蜡乳液。     

综合评分法优化石蜡乳化工艺

采用机械搅拌的方法制备石蜡乳液。选用Span-80、Tween-80、平平加O-25和聚乙二醇为工业石蜡复配乳化剂,考察了乳化石蜡的亲水亲油平衡值(HLB)、乳化剂用量对乳液的分散性、稳定性、表面张力、色泽及外观的影响。结果表明,乳化最佳工艺条件:HLB值9.99,乳化剂与石蜡的质量比0.32,乳化时间25 min,乳化温度80℃,搅拌速度600 r/min,乳化水用量为乳液质量的68%。在此最佳条件下,可制得表面张力低、分散性和稳定性好,均匀细腻的石蜡乳液,乳化颗粒的粒径分布较窄。     

综合评分法优化石蜡乳化工艺

采用机械搅拌的方法制备石蜡乳液。选用Span-80、Tween-80、平平加O-25和聚乙二醇为工业石蜡复配乳化剂,考察了乳化石蜡的亲水亲油平衡值(HLB)、乳化剂用量对乳液的分散性、稳定性、表面张力、色泽及外观的影响。结果表明,乳化最佳工艺条件:HLB值9.99,乳化剂与石蜡的质量比0.32,乳化时间25 min,乳化温度80℃,搅拌速度600 r/min,乳化水用量为乳液质量的68%。在此最佳条件下,可制得表面张力低、分散性和稳定性好,均匀细腻的石蜡乳液,乳化颗粒的粒径分布较窄。     

影响高固含量石蜡乳液颗粒度因素的考察

以58#石蜡为原料,非离子与阴离子表面活性剂复配物为乳化剂,考察了乳化剂的HLB(亲水亲油平衡)值、乳化剂用量、乳化温度、乳化时间、搅拌速度和乳化方法等工艺条件对石蜡乳液颗粒度的影响.结果表明,石蜡乳化剂适宜的HLB值约为9.3,乳化剂的用量、乳化温度、乳化时间、搅拌速度和乳化方法对乳液的粒度均有影响.w(乳化剂)=7%,乳化温度85℃～90℃,乳化时间40 min,搅拌速度为1 000 r/min下采用剂在油中法,制得了平均粒度为1.3 μm,折光率为1.42,固含量约为50%的石蜡乳液,乳液外观为均匀、细腻的乳白色液体.     

造纸用防锈石蜡乳液的制备

采用乳化剂吐温-80、司潘-80与油酸钠进行复配制备防锈石蜡乳液,考察了配方组成、乳化时间、乳化温度和搅拌速度对乳液粒径、分散性和稳定性等的影响,确定了乳化水、58#石蜡、司潘-80、吐温-80和油酸钠的最佳用量分别为乳液质量的69. 8%、19. 9%、4%、6%和0. 3%,得到了最佳制备条件为:乳化时间为20 min,乳化温度为90℃,搅拌速度为1300 r/min。该条件下制得的防锈石蜡乳液稳定性、分散性、固含量等满足造纸行业的要求,因而它可用于造纸工业。     

施胶用乳化蜡的研究

造纸施胶剂多为松香胶与石蜡,采用乳化蜡可以减少松香用量.采用氧化蜡与石蜡混合,加入复配的乳化剂制得乳化蜡.结果表明,加入乳化剂质量分数约7%,在乳化温度85℃、乳化时间30min、搅拌速度800 r/min的工艺条件下,制得的乳化蜡的性质比较稳定,分散性较好,比较适合作造纸施胶用蜡.     

固体切片石蜡乳液制备新工艺

以固体切片石蜡为原料,采用种子乳液聚合法,利用HLB值理论,以复配型乳化剂制得O/D型加水转化为O/W型石蜡乳液,可降低固体石蜡用量,增加乳化水用量,减少生产成本。考察了乳化剂用量、乳化时间、乳化温度以及搅拌速度等因素对石蜡乳液稳定性和分散性的影响。正交实验结果表明:在乳化剂用量为乳液总量的8.6%,乳化时间90 min,乳化温度控制在80±5℃,搅拌速度1500 r/min的反应条件下,可制备出稳定的固体切片石蜡乳液。     

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。