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1.
采用环氧树脂E-51与甲基二乙醇胺(MDEA)在加热条件下进行反应,再利用乙酸中和叔胺,制备出反应型季铵盐乳化剂树脂;将该乳化剂树脂与环氧树脂E-20按照一定比例在一定温度下进行接枝反应,得到水性环氧乳液。对环氧乳液进行了FT-IR表征,考察了反应型季铵盐乳化剂树脂与环氧树脂E-20的比例、反应温度、反应时间对水性环氧乳液稳定性、粒径、配漆后涂膜性能等方面的影响。研究结果表明:在60~70℃下,反应型季铵盐乳化剂树脂加量为8%时,制备的水性环氧乳液具有较好的贮存稳定性,与水性环氧固化剂配漆后的涂膜具有较好的耐盐雾、耐酸碱性能和良好的力学性能。  相似文献   

2.
以无机补强剂、复合偶联剂、复合润湿剂、多元共混树脂乳液、增粘树脂乳液、复合消泡剂等为原料制备了水性塑/塑复合胶粘剂。研究了偶联剂、润湿剂、消泡剂等对其复合膜剥离强度的影响,结果表明,偶联剂、润湿剂、消泡剂等通过形成化学键、增加接触面积、减少表面应力破坏等形式可使其剥离强度得到提高,当用量过多时会引起剥离强度下降。  相似文献   

3.
以聚氨酯乳液为主要连接料,通过加入一定配比的蜡乳液、增粘树脂和偶联剂等制得一种水性可剥离纸塑复膜胶。研究了聚氨酯乳液的类型及其与蜡乳液不同配比,不同增粘树脂的种类和用量,以及不同硅烷偶联剂的用量对纸塑复膜胶性能的影响。结果表明,选择阴离子脂肪族聚氨酯乳液为主要连接料、用量为48.2%,以天然乳胶为增粘树脂、用量为7.8%,而且蜡乳液为39.5%、硅烷偶联剂为4%时,所制备的水性可剥离纸塑复膜胶具有剥离强度适中,纸塑分离时纸张保持完整,粘结面干燥、不返黏的特点,满足纸塑包装的要求。  相似文献   

4.
从聚合物乳液胶体的角度,讨论了水基胶体涂料与溶剂型涂料性能差异的起因;介绍了聚合物乳液主要的胶体特性;简单地分析了聚合物乳液的胶体特性对于工业漆耐盐雾、光泽、流变等性能的影响。提出充分了解水性工业漆的使用特点是优化涂料配方和涂装条件和方式的基础,结合聚合物乳液性能的改进将有助于提高水性工业漆性能的观点。  相似文献   

5.
水性聚合物体系是一种胶体体系.根据胶体科学的基本概念,对水件聚合物体系,包括乳液、微乳液、纳米乳液、乳胶、水分散体、水溶胶、水溶性树脂(聚合物)、水稀释树脂(聚合物)等进行了讨论,分析了不同类型水性聚合物体系各自的典型特征,指出了它们的不同与相似之处.在此基础上,结合目前涂料行业的习惯及结合水性聚合物的性能特征(如可溶解的极性基团的含量、聚合物相对分子质量、聚合物链上亲水/疏水基团比等),对水性聚合物的类别进行了讨论.  相似文献   

6.
周雪婉  方美珊 《广东化工》2011,38(9):30-31,55
采用化学改性法,以邻甲酚醛环氧树脂和二乙醇胺为原料在85℃下反应7 h,制得具有特定环氧值的改性树脂。制得的这种改性树脂在分子结构上即具有环氧基团,又具有亲水性基团,然后用羧酸成盐后,缓慢加入去离子水制备邻甲酚醛环氧树脂乳液。将水性邻甲酚醛环氧树脂乳液和水性专用固化剂三乙烯四胺按10︰1配比,在常温下放置7~8 d得到性能优良的固化剂。本工艺对制成的水性乳液和固化剂的性能进行红外测试和固化表征。  相似文献   

7.
通过选择合适的聚合方法、功能性单体和工艺参数,合成了丙烯酸酯共聚物保护胶体并应用于水性上光油的乳液聚合。利用特性粘度法和DSC法,测定了按不同配方所合成的保护胶体的粘均分子量Mη、玻璃化转变温度Tg以及保护胶体在乳液聚合中添加的最佳比例,并研究了它们对水性上光油乳液的稳定性、凝胶率和成膜性能的影响。结果表明:添加按配方3所合成的保护胶体,比例为0.7%时,聚合所得到的上光油乳液贮存稳定性、机械稳定性和稀释稳定性都有较大幅度提高,凝胶率可降低至接近零,成膜性能优良。  相似文献   

8.
采用丙酮法制备了复合薄膜用的水性聚氨酯(WPU)乳液胶粘剂,研究了催化剂用量对WPU反应速率及其性能的影响。研究结果表明,适量的催化剂能明显加快聚氨酯(PU)预聚体的反应速率;当催化剂质量分数为0.1%时,WPU乳液的粘度和复合薄膜的T型剥离强度最大,但WPU胶膜的玻璃化转变温度(Tg)降低,由未加催化剂时的-25.5℃降低到-29.1℃。  相似文献   

9.
介绍了一种单组分自干水性耐高温防腐涂料的制备方法,以两种水性有机硅树脂乳液为成膜物,从树脂的配比、颜填料的选择、助剂的应用等方面着手,进行了配方优化组合,在利用现有工艺条件、生产设备、涂装设备的前提下,开发出常温自干型耐700℃水性耐高温涂料。  相似文献   

10.
开发了一种应用于工业防腐领域的水性工业涂料。采用特定的丙烯酸乳液和水性环氧酯树脂作为成膜物,添加颜填料和合适的助剂,制备得到水性涂料。研究了水性树脂种类、涂料助剂等配方参数对涂料性能的影响,得到了综合性能优异的水性涂料配方。  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   

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14.
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   

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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