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1.
含羟基叔氟微乳液的合成及水性双组分聚氨酯清漆的制备   总被引:4,自引:0,他引:4  
以叔碳酸乙烯酯、丙烯酸六氟丁酯、含羟基单体、反应型阴离子乳化剂、非离子乳化剂、(甲基)丙烯酸及其酯类单体等为原料制备了新型含羟基叔氟共聚物乳液。考察了反应温度、乳化剂用量、乳化剂配比、引发剂用量、有机氟单体等对乳液聚合过程的影响;并对制备的乳液进行了红外、机械稳定性等的表征,确定了最佳反应条件。利用该新型乳液和水性固化剂,制备了常温固化水性双组分聚氨酯涂料,并进行了测试表征。  相似文献   

2.
以环氧树脂E-44与丙烯酸反应得到的乙烯基环氧树脂(VER)为原料,制备出了一种新型的环氧树脂改性水性聚氨酯树脂PUER-2乳液,比较了双键封端聚氨酯(PUV)、环氧树脂改性聚氨酯(EPU)、乙烯基环氧树脂改性聚氨酯(PUER)乳液的贮存稳定性、胶束结构及涂膜的耐水、耐化学品、力学性能等方面的差异,结果表明:采用此方法制备的环氧树脂改性水性聚氨酯树脂PUER-2明显改善了乙烯基封端的水性聚氨酯的耐水性和耐溶剂性及其膜的拉伸强度,并且克服了环氧树脂直接用于水性聚氨酯树脂改性制备的EPU乳液贮存稳定性差的不足。  相似文献   

3.
以异佛尔酮二异氰酸酯(IPDI)、二羟甲基丙酸(DMPA)、聚醚多元醇(PPG、PTMG、PEG)等为主要原料进行反应,分别采用亚硫酸氢钠(NaHSO3)和甲乙酮肟(MEKO)封端,合成了系列水性聚氨酯乳液。讨论了多元醇类型及配比、不同封端剂对水性聚氨酯乳液及胶膜性能的影响。结果表明,由PPG-220合成的水性聚氨酯具有较好的耐水性,由PTMG2000合成的水性聚氨酯具有优异的力学性能,当PPG-220∶PTMG2000摩尔比为3∶1复配使用时所得的水性聚氨酯能达到优良的综合性能。以NaHSO3为封端剂其成膜性较好,解封温度为60.5~68.0℃;以MEKO为封端剂其稳定性较好,解封温度为110~124℃。  相似文献   

4.
赵瑞华  李树材  刘景芳 《涂料工业》2007,37(11):19-21,25
以苯酚、ε-己内酰胺(ε-CL)、丙二酸二乙酯等封闭剂封闭TDI型聚氨酯预聚物,得到了一系列单组分聚氨酯乳液,并对其乳液稳定性、粒径,胶膜耐水性等性能进行了研究,发现胶膜的耐溶剂性、耐水性等性能均有提高。采用差示扫描量热法(DSC)对封闭型预聚物的解封闭温度进行了研究,发现以ε-己内酰胺作封闭剂时聚氨酯预聚物在160℃左右解封,以丙二酸二乙酯作封闭剂时在140℃左右解封。  相似文献   

5.
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   

6.
以羟基丙烯酸乳液和水性聚氨酯固化剂为成膜基料体系,配以优选助剂、颜填料和助溶剂等制备了满足车用工艺及性能要求的双组分水性聚氨酯中涂漆.考察了羟基丙烯酸乳液、水性聚氨酯固化剂树脂、n(-NCO)/n(-OH)比例及助溶剂等因素对涂膜外观及性能的影响,经配方优化后,得到了最佳的涂层效果.  相似文献   

7.
采用甲苯二异氰酸酯(TDI)、三羟甲基丙烷(TMP)、二羟甲基丙酸(DMPA)为原料,2-甲基咪唑为封闭剂,三乙胺为中和剂制备了水分散封闭异氰酸酯(WBI)乳液,考察了中和剂和Zeta电位(ζ-电位)对WBI乳液稳定性的影响,探讨了乳液耐电解质能力及其温敏特性对其解封温度及双组分聚氨酯漆膜性能的影响。实验结果表明:用三乙胺作为中和剂时,乳液粒径较小,稳定性及贮存稳定性均较好,最佳中和度为100%。随DMPA用量的增加,乳液的ζ电位绝对值增大,乳液粒径减小、耐电解质能力增强,乳液的稳定性提高。乳液的Zeta电位及粒径受温度影响较小,说明乳液较为稳定。DMPA用量为20%~25%(摩尔分数)较适宜。差示扫描量热法(DSC)分析表征其解封温度为125.6~138.1℃,应用表明此类WBI作为固化剂可以赋予涂料较好的耐水性、耐醇性、硬度及耐冲击性。  相似文献   

8.
俞佳  贺江平  白蕊 《粘接》2012,(7):52-56
采用甲苯二异氰酸酯(TDI)、聚丙二醇-400(PPG-400)为原料,丙酮为溶剂,亚硫酸氢钠为封端剂,借助外乳化法,合成了一种封端型水性聚氨酯固化剂。将这种固化剂与一定比例的淀粉糊化液混合后,对汽车工业用滤纸进行耐水性能整理。实验结果表明,在一定温度下封端型水性聚氨酯固化剂解封出异氰酸酯基与吸附在滤纸上的淀粉及滤纸自身的羟基反应生成氨基甲酸酯,能够有效地提高滤纸的耐水性;同时也赋予滤纸良好的硬挺度、强度、透气性。合成成本低廉、方法简单。  相似文献   

9.
水性涂料     
题述环境友好型双组份水性氟涂料组合物含主要组分和一种固化剂。其中,主要组分含丙烯酸改性的氟乳液树脂1ON50份(质量份,下同)、水性聚氨酯乳液树脂(含羟基基团)10-30份,颜填料10-25份,亲水性溶剂1—1O份、水5-15份j固化剂含30-60份封闭型异氰酸酯和水。该环境友好型双组分水性氟涂料组合物具有较高的防污性、耐侯性以及无VOC限制要求等优点。  相似文献   

10.
聚酯型阴离子水性聚氨酯乳液的合成及性能研究   总被引:1,自引:0,他引:1  
采用聚酯二醇(JW 2503),甲苯二异氰酸酯(TD I),二羟甲基丙酸(DMPA)为基本原料,用丙酮法合成了稳定的聚酯型阴离子水性聚氨酯乳液。讨论了NCO/OH的摩尔比、反应温度、反应时间、催化剂用量等因素对水性聚氨酯乳液性能的影响。实验结果表明,当初聚NCO/OH=2.3,总体NCO/OH=1.1、初聚反应温度为(65±1)℃、扩链反应温度为(82±1)℃、中和反应温度为30℃~40℃、初聚反应时间为2.0h、扩链反应时间为1.5h、催化剂用量为0.03%时,合成的聚酯型阴离子水性聚氨酯乳液具有较好的贮存稳定性,且涂膜的耐水性和机械性能良好。  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   

14.
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   

20.
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   

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