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1.
采用聚乙烯蜡对石蜡进行催化氧化改性,对改性石蜡制备微乳液进行了研究,考察了微乳液的配方组成以及乳化条件对制备微乳液的影响.结果表明当蜡样、乳化剂的质量比为1:0.60,乳化时间为50 min,乳化温度为90~95 ℃,搅拌速度为1 200~1 500 r/min 时可得到稳定的蜡微乳液.  相似文献   

2.
采用聚乙烯蜡对石蜡进行催化氧化改性,以得到的高硬度氧化蜡为原料制备乳化型地板上光蜡。对高硬度氧化蜡乳化过程进行了研究,考察了不同微乳液的配方组成以及乳化条件对制备微乳液的影响,结果表明,乳化剂[m(Tween-80)/m(Span-80)=8.5]和蜡的质量比为0.60,乳化时间为50 min,乳化温度为90-95℃,搅拌速度为1 200-1 500 r/min时可制得外观、光泽、成膜性等性能优良乳化型地板上光用蜡,与使用天然巴西棕榈蜡相比成本较低。  相似文献   

3.
采用聚乙烯蜡为原料,通过催化氧化反应对石蜡进行改性研制出质量和性能与天然巴西棕榈蜡相似的氧化蜡,用其代替天然巴西棕榈蜡制备乳化型汽车上光蜡。对氧化蜡制备微乳液进行了研究,考察了微乳液的配方组成以及乳化条件对制备氧化蜡微乳液的影响,结果表明蜡样和乳化剂的质量比为1∶0.50,乳化时间为50min,乳化温度为90~95℃,搅拌速度为1200~1500r/min时可制得外观、光泽、成膜性等方面性能优良的汽车上光用蜡。  相似文献   

4.
对氧化蜡的乳化工艺进行研究。考察了乳化剂配方、搅拌速度、乳化温度、乳化时间对氧化蜡乳液性能的影响。结果表明:石蜡通过氧化改性,当乳化剂A、乳化剂B、助乳化剂C的浓度分别为4%、3.0~3.5%、1.0%,搅拌转速为1 000~1 200 r/min、乳化时间为20~25 min、乳化温度为85~90℃时能得到性能优良的氧化蜡微乳液。  相似文献   

5.
研究了用氧化改性聚乙烯蜡制备一种非离子型乳液的方法。在确定最佳乳化温度105℃条件下考查了乳化剂用量、乳化工艺、助剂对乳液稳定性的影响。研究结果表明,当非离子乳化剂A、非离子乳化剂B助溶剂C和中和剂氢氧化钠分别为氧化改性聚乙烯蜡的25.15%,3.25%,1.6%和1.5%(w),乳化时间为20~30min,搅拌速度为1 000~1 400 r/min时,可以制取一种满足用作纺织柔软剂要求、固含量为20%、平均粒径小于0.1μm的蜡乳液。  相似文献   

6.
采用高压分散乳化,以氧化聚乙烯蜡为原料,脂肪醇聚氧乙烯醚、月桂基硫酸钠为乳化剂,丙三醇为助乳化剂,氢氧化钾为pH调节剂,制备氧化聚乙烯蜡微乳液。考察了乳化剂种类、乳化剂配比、乳化温度、搅拌速率对氧化聚乙烯蜡微乳液粒径分布、稳定性的影响。结果表明:乳化温度为150℃、时间为50 min、搅拌速度为800 r/min、乳化剂为氧化聚乙烯蜡的30%、脂肪醇聚氧乙烯醚和月桂基硫酸钠的质量比为4∶1、助乳化剂为3%时,可制得固含为34%~36%,粒径为400~500 nm,黏度为30~80 mPa·s,半透明且在55℃下贮存90 d,4 000 r/min转速下进行离心10 min不出现分层、沉淀,稳定性良好的氧化聚乙烯蜡微乳液。  相似文献   

7.
阳-非复合离子型氧化聚乙烯蜡乳液广泛应用于皮革涂饰、造纸、印染等领域,该文用三乙醇胺对氧化聚乙烯蜡进行酯化改性,再用相转变法和复合乳化体系对酯化改性的氧化聚乙烯蜡进行乳化,并对乳液性能进行检测分析。实验结果表明,三乙醇胺对氧化聚乙烯蜡进行酯化改性后,可明显提高氧化聚乙烯蜡的可乳化性和乳液的稳定性。乳化剂的种类、用量、乳化温度以及剪切搅拌速度等乳化因素对乳液性能有较大影响。乳化实验优化的条件为:乳化剂OS-15用量为氧化聚乙烯蜡质量的15%,乳化剂1631用量为氧化聚乙烯蜡质量的5%;乳化温度为90~95℃;连续剪切分散40~60min。  相似文献   

8.
吴国江  陈艳华  王丽君 《当代化工》2012,41(5):460-461,465
研究了用58#全炼蜡、改性高分子聚合物制备水果保鲜光乳化蜡的方法.考查了石蜡、改性高分子聚合物二者的比例、复合乳化剂对乳液性能的影响.实验结果表明,当乳化剂用量为乳液质量的5%,乳化温度为90~95℃,乳化时间为30 ~40 min时,可以制取一种水果保鲜乳化蜡.  相似文献   

9.
采用高压乳化法,以氧化聚乙烯(OPE)蜡为原料用单一乳化剂制备了淡黄色、半透明的非离子型OPE蜡微乳液.考察了非离子型乳化剂的用量和乳化压力对OPE蜡微乳液的乳胶粒子粒径和粒径分布的影响.结果表明:增加乳化剂用量或增加乳化压力均有利于降低水的表面张力,形成粒径更小的OPE乳胶粒子.在乳化剂用量为OPE蜡的25%、助剂用量为乳化剂的5%,乳化时压力为(8.5±0.5)MPa时,可获得性能良好的非离子型OPE微乳液.  相似文献   

10.
姜易虹  魏铭  刘辉  杨静庭 《化工进展》2016,35(9):2941-2944
旨在对低密度聚乙烯蜡进行化学接枝改性,改善其可乳化性能,从而制备高稳定性改性聚乙烯蜡微乳液。首先以丙烯酸作为接枝单体,采用悬浮溶胀接枝法对低密度聚乙烯蜡进行化学接枝改性;然后,通过选取适当的阴离子乳化剂和非离子乳化剂的复配体系,对接枝改性的聚乙烯蜡产物进行乳化。结果表明:采用SDS和Tween80等比例复配,控制乳化温度为90~95℃,乳化剂用量为聚乙烯蜡的10%、乳化时间为30min时,采用相转变乳化法可制得高稳定性的聚乙烯蜡微乳液。采用FTIR对改性聚乙烯蜡进行了结构表征,证明了丙烯酸被成功地接枝到了聚乙烯蜡分子上,并通过DSC分析研究了其熔点和结晶情况的变化:聚乙烯蜡的熔点为102.41℃,丙烯酸接枝改性聚乙烯蜡的熔点为102.85℃;改性聚乙烯蜡与未改性的聚乙烯蜡的比结晶度为77.7%。  相似文献   

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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   

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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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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   

18.
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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