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1.
新型、高效、无毒的钙皂、锌皂热稳定剂的研究   总被引:22,自引:5,他引:17  
通过静态及动态的热稳定实验来评价新型钙皂、锌皂热稳定剂的稳定效果。研究结果表明:这种新型钙皂、锌皂具有较高的热稳定效果,在170℃下的热稳定时间是硬脂酸钙硬脂酸锌的2倍以上,完全可以替代热稳定效果较差的硬脂酸钙、硬脂酸锌,可用于无毒PVC制品中,具有良好的经济效益及社会效益。  相似文献   

2.
无毒金属皂间协同热稳定效果的研究   总被引:4,自引:0,他引:4  
林美娟 《中国塑料》2000,14(10):67-71
通过静态刚果红法、热烘法来研究锌皂与各种不同金属皂间的协同热稳定效果。研究结果表明:初期型锌皂与其它长期型金属皂复合能显著改善初期热烘变色,表现良好协同稳定作用;新型锌的热稳定时间是硬脂酸锌的两倍,采用新型锌的复合皂的热稳定性能均比采用硬脂酯锌的复合皂明显提高,其中新型锌与硬脂酸钙的复合皂热稳定性能最好。  相似文献   

3.
高效新型锌皂热稳定剂   总被引:2,自引:0,他引:2  
通过静态刚果红法及热烘法来研究合成的新型锌皂在软质PVC体系中的热稳定性能以及与硬脂酸钙的协同稳定性能。结果表明:新型锌皂的热稳定性优于其他的锌皂,其热稳定时间是其他锌皂的两倍;与硬脂酸钙复合,能发挥良好的协同稳定作用。  相似文献   

4.
采用离子交换法制备了硬脂酸柱撑类水滑石,采用红外光谱分析对其结构进行了表征。通过HAAKE流变仪、颜色测定仪研究了硬脂酸柱撑类水滑石与钙锌热稳定剂并用时的热稳定性,重点考察了水滑石的结构对PVC稳定性能的影响。结果表明硬脂酸柱撑类水滑石与钙皂/锌皂复配显著改善了PVC热老化过程中的初期着色性。  相似文献   

5.
采用离子交换法制备了硬脂酸柱撑类水滑石,并用红外光谱分析对其进行了表征.通过HAAKE流变仪、颜色测定仪研究了硬脂酸柱撑类水滑石与钙锌热稳定剂并用时的热稳定性,重点考察了水滑石的结构对PVC稳定性能的影响.结果表明硬脂酸柱撑类水滑石与钙皂/锌皂复配显著改善了PVC热老化过程中的初期着色性.  相似文献   

6.
将硬脂酸锌、硬脂酸钙与稀土热稳定剂硬脂酸镧及辅助热稳定剂复配成钙锌复合热稳定剂。通过动态热稳定试验,确定了最佳钙/锌复合热稳定剂与稀土热稳定剂质量比。通过动态热稳定试验及刚果红热稳定试验,确定辅助热稳定剂β-二酮的最佳用量,用研制的钙锌复合热稳定荆与国外同类产品进行了对比试验。结果表明,自制的热稳定剂具有热稳定时间长、塑化时间短的优点,将此热稳定剂用于PVC给水管材中,管材性能检测结果表明,管材质量符合国标GB/T10002.1-2006的要求。  相似文献   

7.
采用变色法对硬质聚氯乙烯(PVC)用钙/锌复合热稳定剂的主体、有机辅助稳定剂、功能助剂之间的协同作用进行了研究,得到了硬质PVC用新型高效钙/锌复合热稳定剂的实用配方,并与4种市售稳定剂进行了静态、动态热稳定性比较。结果表明,材料的初期色泽和长期热稳定性主要决定于硬脂酸钙与硬脂酸锌的比例,调整比例可以使其性能有一定程度的改善;钙和锌的硬脂酸盐180 ℃一同预热5 min后,协同作用得到增强;该复合热稳定剂塑化流变性理想,可以在不改变加工工艺及配方的条件下等量替代其他几种热稳定剂;动态热稳定时间约30 min,与进口钙锌稳定剂相近。  相似文献   

8.
利用转矩流变仪和白度颜色测定仪,研究硬脂酸钙和锌盐复配体系对聚氯乙烯(PVC)加工性能及热稳定性能的影响.结果表明:当硬脂酸钙和硬脂酸锌的质量比为5:4时,PVC的动态热稳定时间为767 s,在10 min和15 min加工时间下的蓝光白度分别为45.48和37.40,其综合性能最好.硬脂酸钙/十二酸锌体系初期热稳定效果最好,在10 min加工时间下的蓝光白度为52.88.硬脂酸锌、十二酸锌和硬脂酸钙三者复配使用没有协同作用.  相似文献   

9.
介绍了改性水滑石的结构、作用机理及改性的关键技术,并比较了改性水滑石、硬脂酸钙、硬脂酸锌、硬脂酸钡、三盐在PVC体系中的热稳定性能以及协同稳定性能。重点研究金属皂与改性水滑石类热稳定剂复配用量对PVC脱氯化氢反应的影响,同时比较了复配有改性水滑石的钙锌复合稳定剂与三盐的热稳定性,结果表明复配改性水滑石产品的钙锌系列不仅明显改善PVC初期着色性,而且长期热稳定性能也大幅提高,完全可以替代铅盐使PVC电缆料达到国标要求。  相似文献   

10.
合成了新型无毒没食子酸锌/没食子酸钙、没食子环氧树脂、邻甲酚醛环氧树脂,并利用复配工艺制备了新型复合热稳定剂,考察了不同组成热稳定剂对聚氯乙烯热稳定效果的影响。结果表明:没食子酸锌/没食子酸钙体系、没食子酸锌/没食子酸钙复配没食子环氧树脂体系和没食子酸锌/没食子酸钙复配邻甲酚醛环氧树脂体系的热稳定效果均优于传统的硬脂酸锌/硬脂酸钙体系。其中,没食子酸锌/没食子酸钙复配邻甲酚醛环氧树脂体系稳定性最好,具有最佳协同效果,试样的初始热降解温度比传统硬脂酸锌/硬脂酸钙体系提高了41.6℃,静态热稳定时间提高了65%。  相似文献   

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12.
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.  相似文献   

13.
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.  相似文献   

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15.
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.  相似文献   

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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.  相似文献   

19.
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.  相似文献   

20.
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。  相似文献   

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