首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
用2,2-二羟甲基丁酸(DMBA)与环氧树脂E-51(EP)发生开环反应,在树脂分子链上引入伯羟基,再用马来酸酐(MA)与伯羟基进行醇解反应引入羧基。加入三乙胺中和成盐后,制得阴离子型环氧树脂。结果表明所合成的改性环氧树脂具有良好的水溶性,将合成的改性树脂用上海汉中公司H205B固化剂固化成膜。膜性能良好:涂膜平整无气泡,25℃下表干时间为2 h,涂膜硬度5H,耐酸碱性72 h无变化。  相似文献   

2.
高性能水性UV固化聚氨酯的合成与性能研究   总被引:2,自引:0,他引:2  
用环氧丙烯酸酯(EA)、羟基硅油合成了环氧/有机硅改性水性光固化聚氨酯乳液(WPU);研究了EA、羟基硅油、亲水扩链剂二羟甲基丁酸(DMBA)的用量,中和度和硅烷偶联剂的添加量对乳液和涂膜性能的影响。用红外光谱和接触角测量仪对树脂进行表征。结果表明:通过EA、羟基硅油改性的水性光固化聚氨酯涂膜的硬度高、附着力强、耐水性较好,克服了未改性水性光固化聚氨酯的缺点。当EA用量为4%、羟基硅油为2%、DMBA为8%、中和度为80%、硅烷偶联剂的添加量为1%时,水性光固化聚氨酯乳液的综合性能较好,树脂接触角大大提高。  相似文献   

3.
水性聚氨酯耐水性的研究   总被引:10,自引:3,他引:7  
以聚醚多元醇和甲苯二异氰酸合成了水性聚氨酯乳液。研究了二羟甲基丙酸亲水扩链剂、三羟甲基丙烷交联剂和乙二胺对水性聚氨酯涂膜耐水性的影响,制备了耐水性好的水性聚氨酯树脂。  相似文献   

4.
双组分水性聚氨酯涂料的合成与表征   总被引:38,自引:0,他引:38  
随着环境法规对涂料的挥发性有机化合物(VOC)含量的限制,高性能与低VOC含量相结合的双组分水性聚氨酯涂料成为涂料工业发展的趋势。采用三羟甲基丙烷(TMP)为扩链剂合成具有交联结构的水性聚氨酯分散体多元醇,与多异氰酸酯固化剂组成双组分水性聚氨酯涂料。研究发现双组分涂膜的机械性能和外观是由合成的水性聚氨酯多元醇的扩链剂(TMP)含量,中和度,中和工艺和双组分涂料的配比等决定的。当扩链剂含量为2%-4%,中和度为100%,NCO:OH=1.0-1.2时所得双组分水性聚氨酯涂膜外观好,快干,硬度高和施工方便。  相似文献   

5.
高稳定性聚酯型阴离子水性聚氨酯乳液的合成工艺研究   总被引:8,自引:0,他引:8  
采用甲苯二异氰酸酯与聚酯二醇、亲水扩链剂和其它多元醇反应合成了聚酯型阴离子性聚氨酯乳液。讨论了扩链剂的种类、加料方式、添加量及中和剂种类和中和度等因素对水性聚氨酯乳液及其涂膜性能的影响。研究发现:采用二羟甲基丙酸为亲水扩链剂,用溶液加料的方式,用氢氧化钾作中和剂且中和度为90%~100%时合成的聚酯型阴离子水性聚氨酯乳液具有良好的贮存稳定性,且涂膜的耐水性和机械性能良好。  相似文献   

6.
以聚酯多元醇、4,4’-二环己基甲烷二异氰酸酯和二羟甲基丙酸为原料,采用预聚物混合工艺合成水性聚氨酯分散体,研究了中和方式、乳化条件和扩链方式对乳液及其涂膜性能的影响,确定了最佳乳化条件、中和工艺和扩链方式。  相似文献   

7.
采用丙酮法利用聚酯二元醇(PE-1000)、二羟甲基丙酸(DMPA)、1,6-己二醇(HDO)、三羟甲基丙烷(TMP)和异佛尔酮二异氰酸酯(IPDI)反应,经中和、加水分散,合成出羟基型水性聚氨酯.并用制成的树脂和水性多异氰酸酯固化剂(Bayhydrol XP2655)以及消泡剂、流平剂、助溶剂等制备出柔性水性木器清漆.通过傅里叶红外光谱、差示扫描量热仪、热重分析仪、粒度仪、各种涂膜测试仪等仪器进行表征.测试结果表明:当树脂的数均分子量设计为5 000~6 000、DMPA的含量为4.5%~5.0%、HDO的含量为8.0%~10.0%、TMP的含量为5.0%~5.5%、中和度为1.0左右时制备出的树脂粒径、黏度和吸水率较小,贮存期l a以上.且条件范围内合成的水性木器清漆耐磨性好,丰满度高,柔软性佳,手感好,耐水、耐醇性好.  相似文献   

8.
环氧改性水性聚氨酯涂料的合成与性能研究   总被引:34,自引:5,他引:34  
采用环氧树脂与聚醚、二羟甲基丙酸(DMPA)和甲苯二异氰酸酯(TDI)反应制备水性聚氨酯涂料。研究发现随着所用的环氧树脂的环氧值的降低,改性水性聚氨酯涂膜的硬度和拉伸强度逐渐提高,断裂伸长率则随着降低。选用环氧值为0.44的环氧树脂所合成的改性水性聚氨酯的涂膜硬度达到玻璃硬度0.70;随着环氧树脂添加量增大,涂膜机械性能增加。采用后添加环氧树脂的合成工艺,可制备贮存稳定的水性聚氨酯乳液;凝胶渗透色谱(GPC)分析表明环氧树脂改性水性聚氨酯提高了聚氨酯的分子量。性能测试表明环氧改性水性聚氨酯涂料具有涂膜硬度高、耐水性好和耐溶剂性好等优点。  相似文献   

9.
孙绍晖  孙培勤  刘大壮 《涂料工业》2007,37(7):14-17,21
在掌握环氧树脂与丙烯酸树脂酯化反应凝胶规律的基础上,在临界凝胶方程给出的环氧/叔胺/丙烯酸树脂三角图的非凝胶区域,利用酯化反应合成了不同三元配比的六种环氧丙烯酸树脂复合物,通过研究这六种复合物的相对分子质量、加水乳化和涂膜性能等变化规律,最终给出适合做防腐涂料的配方选择范围和涂料配方设计的指导原则。  相似文献   

10.
陆雪良  曾小君  陈船妹 《粘接》2004,25(2):19-22
采用聚酯二醇(JW2503)、甲苯二异氰酸酯(TDI)、N-甲基二乙醇胺(MDEA)为基本原料,用丙酮法合成了聚酯型阳离子水性聚氨酯乳液。讨论了NC0/OH量比、MDEA的加入方式及其用量、反应温度等因素对乳液性能的影响。实验结果表明,当合成条件为:NCO/OH量比为2.7,MDEA的用量占树脂的6%-7%,且采用饥饿加料的方式滴加MDEA,初聚体合成温度为60—65℃,引入亲水扩链基团的扩链反应温度为40℃,中和度90%-100%时,合成的聚酯型阳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   

11.
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.
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.
16.
17.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号