环氧树脂改性水性聚氨酯的制备与性能研究

以异氟尔酮二异氰酸酯(IPDI)、聚四氢呋喃醚二醇(PTMG)以及二羟基甲基丙酸(DMPA)为主要原料合成水性聚氨酯(WPU)预聚体,在此基础上加入环氧树脂(EP,E-44)制备了环氧树脂改性水性聚氨酯(PUE)复合乳液。探讨了不同环氧树脂含量对复合乳液性能的影响,并对胶膜的力学性能、吸水率、接触角和热性能等进行了表征。结果表明,适量的环氧树脂改性过后的复合乳液比较稳定;随着环氧树脂含量的增加,乳液粒径和黏度增大,同时胶膜的拉伸强度增大,水的接触角增大,胶膜的热稳定性增加。E-44质量分数为7%~9%时,复合乳液及其胶膜的综合性能较好。     

基于柠檬酸架构的水性光固化环氧-聚氨酯的制备与性能研究

用甲基丙烯酸羟乙酯(HEMA)与一水合柠檬酸反应生成柠檬酸酯,然后将其与环氧树脂E-51或者甲基丙烯酸缩水甘油酯(GMA)反应,利用环氧开环形成的仲羟基将环氧树脂引入到聚氨酯的主链中,制备了基于柠檬酸架构的水性光固化环氧-聚氨酯。采用纳米粒度仪、光学接触角仪、电子拉力机等对胶膜的结构与性能进行了测试。研究了环氧树脂E-51或GMA的加入对聚氨酯胶膜的耐水性、力学性能、硬度、水接触角、热稳定性的影响。结果表明:随着E-51和GMA的加入,乳液粒径逐渐增大、分布变宽,胶膜热稳定性增强、吸水率大幅度降低、接触角增加;胶膜的拉伸强度和断裂伸长率大幅度增大。     

高固含量环氧改性磺酸盐型水性聚氨酯的合成与表征

以异氟尔酮二异氰酸酯(IPDI)、六亚甲基二异氰酸酯(HDI)、聚己二酸-1,4-丁二醇酯(PBA)为主要原料,以1,4-丁二醇为小分子扩链剂,以乙二胺基乙磺酸钠为亲水性扩链剂,并用环氧树脂E-51作为改性剂,得到固含量为50%的环氧树脂改性磺酸盐型水性聚氨酯乳液SWPU-E。实验研究了环氧用量对乳液的粒径及其分布和对胶膜力学性能的影响;实验还采用红外、核磁、热重分析等方法对胶膜的结构和热稳定性等进行了深入的分析。结果表明:环氧树脂的羟基和环氧基团参与了反应,生成了环氧改性的水性聚氨酯结构;随着环氧用量的增加,乳液的平均粒径从95.8 nm增加到169 nm,粒径分布变宽;胶膜的拉伸强度随之变大,当环氧用量低于4%时,拉伸强度明显增加,由16.21 MPa增加到43.7 MPa,之后拉伸强度增加缓慢;胶膜的热稳定性随环氧用量的增加得到明显提高,初始分解温度、转折点温度、分解终点温度均朝高温方向移动。     

基于NaOH中和剂制备羧酸型水性聚氨酯及其性能分析

以二羟甲基丙酸(DMPA)为亲水扩链剂，与异佛尔酮二异氰酸酯、聚己二酸-1,4-丁二醇酯二醇等反应合成聚氨酯预聚体，以NaOH为中和剂，制备了一系列羧酸型水性聚氨酯(WPU)。通过观察乳液外观，测试乳液的粒径和离心稳定性及胶膜的傅里叶变换红外光谱(FTIR)、力学性能、水接触角和吸水率，探究了DMPA含量对基于NaOH中和剂的水性聚氨酯性能的影响。结果表明，采用NaOH作为中和剂制备稳定的WPU乳液，并且，随着预聚体中亲水基团含量的增加，乳液的平均粒径和胶膜的水接触角逐渐减小，水性聚氨酯膜的拉伸强度逐渐增大，当亲水基团含量为1.1%时，WPU乳液粒径为43.95 nm,胶膜拉伸强度为51.85 MPa。     

环氧树脂改性水性聚氨酯的制备及其性能研究

以异佛尔酮二异氰酸酯(IPDI)、聚酯多元醇(PEDA)为主要原料,二羟甲基丙酸(DMPA)为亲水性扩链剂,通过添加不同种类和不同含量的环氧树脂(E-12、E-51)进行改性,合成了环氧树脂改性水性聚氨酯(EWPU)乳液,讨论了DMPA含量、环氧树脂种类和含量对EWPU乳液粒径、粘度、贮存稳定性以及胶膜吸水率和力学性能的影响。结果表明,环氧树脂中的环氧基团在整个反应过程中没有参与反应,保留在EWPU乳液中;DMPA质量分数为4%、环氧树脂E-12质量分数为8%时,制备的EWPU乳液和胶膜的性能较好。     

新型环氧树脂改性水性聚氨酯的合成与性能研究

选用异佛尔酮二异氰酸酯( IPDI)、聚四氢呋喃二醇(PTMG)、二羟甲基丙酸(DMPA)及一缩二乙二醇(DEG)为主要原料,经相转化法合成了阴离子型水性聚氨酯(WPU)自乳化乳液;再加入过量胺开环的环氧树脂E-51,后扩链30 min,得到一系列状态稳定的环氧树脂E-51改性水性聚氨酯(EPU)乳液.并对乳液及胶膜进行了结构表征和性能测试,研究表明:环氧树脂E-51成功被乙二胺开环,用其改性水性聚氨酯,可以使胶膜的机械性能增强,24h吸水率降至1.46％,硬度、耐热性能均得到较大提高.     

环氧树脂对层压复合用水性聚氨酯性能的影响

采用异佛尔酮二异氰酸酯(IPDI)、聚己二酸丁二醇酯(PBA)、二羟甲基丙酸(DMPA)、环氧树脂等原料制备了层压复合用水性聚氨酯(WPU)胶粘剂,考查了环氧树脂用量对其性能的影响。结果表明,随着环氧树脂用量的增加,WPU乳液黏度增加,粒径逐渐变大,稳定性变差;经环氧树脂改性的WPU,胶膜的耐水性优于未改性胶膜,力学性能得到提高。     

非离子型水性环氧-聚氨酯乳液的制备及性能研究

以异佛尔酮二异氰酸酯(IPDI)、聚乙二醇(PEG)、环氧树脂E-51为主要原料,合成了聚氨酯预聚体接枝改性的环氧树脂,并以改性环氧树脂作为乳化剂,乳化环氧树脂E-51,通过相反转法制备了纳米级的非离子型水性环氧-聚氨酯乳液。采用红外光谱(FT-IR)对改性环氧树脂进行结构表征,通过纳米粒度分析仪和透射电镜(TEM)研究了乳液的粒径和形貌,同时研究了PEG相对分子质量和聚氨酯预聚体用量对乳液稳定性、粒径的影响。结果表明:当PEG相对分子质量为6 000,聚氨酯预聚体含量为20%时,制备的水性环氧-聚氨酯乳液的综合性能最佳,此时所制备乳液稳定性好,粒径小于150 nm。     

甲基丙烯酸十二氟庚酯改性水性聚氨酯

采用聚已二酸丁二醇酯(PBA)、异氟尔酮二异氰酸酯(IPDI)、二羟甲基丙酸(DMPA)、甲基丙烯酸十二氟庚酯(MBFA-12)等原料合成了含氟水性聚氨酯乳液(WPU-F),考察了MBFA-12的用量对WPU-F乳液的粒径与黏度,WPU-F胶膜的吸水率、接触角、附着力、硬度、拉伸强度、热力学性能等的影响.结果表明:用MBFA-12改性水性聚氨酯,在提高水性聚氨酯胶膜的拉伸强度、附着力、热力学性能的同时,由于侧链上密集的-CF3作用,接触角从70.7(°)增加到107.6(°),胶膜吸水率从61.3%降到15%以下,大大提高了聚氨酯的耐水性.     

水性聚氨酯热熔胶的制备及性能

以甲苯二异氰酸酯、聚己二酸-1,4-丁二醇酯(PBA)、聚环氧丙烷醚三醇(PPO)为主要单体,2,2-二羟甲基丙酸(DMPA)为羧基单体,1,4-丁二醇为扩链剂合成了聚氨酯预聚体,并以三乙胺为中和剂,进一步制备了阴离子水性聚氨酯乳液。考察了交联单体PPO含量对乳液及胶膜性能的影响。结果表明,n(PBA)∶n(PPO)=9∶1时,乳液稳定性好,聚氨酯膜的拉伸强度为44.18 MPa,断裂伸长率为742.94%,其热分解温度为239℃,对皮革的黏接强度高于皮革的内聚强度,对不锈钢的黏接剪切强度为14.76 MPa。     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

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.     

2007～2008年世界塑料工业进展

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.     

2005～2006年国外塑料工业进展

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。