水性聚氨酯的合成与改性

以甲苯二异氰酸酯(TDI)、聚醚二元醇(N220)和二羟甲基丙酸(DMPA)为主要原料,采用三羟甲基丙烷(TMP)进行交联改性合成了水性聚氨酯(WPU),研究了n(-NCO)/n(-OH)、DMPA及TMP对WPU的耐水性、稳定性和力学性能的影响。研究发现,改性后的乳液常温贮存稳定性好,适度交联可提高胶膜的拉伸强度及耐水性。     

有机硅改性磺酸/羧酸型水性聚氨酯的研究

以聚醚多元醇（N-210）和2,4-甲苯二异氰酸酯（TDI）为原料,以自制的磺酸型亲水单体1,2-二羟基-3-丙磺酸钠（DHPA）和二羟甲基丙酸（DMPA）为扩链剂,采用氨丙基三甲氧基硅烷和氨乙基氨丙基三甲氧基硅烷对纯水性聚氨酯（WPU）进行改性,并对有机硅改性WPU胶膜的性能进行了研究。结果表明：WPU分别经两种不同结构的有机硅改性后,其胶膜的力学性能略高于未改性WPU,但耐水性和耐热性则明显高于未改性WPU。     

交联剂种类对水性聚氨酯性能的影响

以异佛尔酮二异氰酸酯(IPDI),聚醚多元醇N210、N220为主要原料,分别采用聚醚三元醇N330,蓖麻油(C.O),三羟甲基丙烷(TMP),季戊四醇(PER)为交联剂,合成了一系列状态稳定的水性聚氨酯乳液,探讨了不同种类的交联剂对胶膜力学性能、胶膜耐水性以及耐热性能的影响。实验表明,用TMP交联改性的水性聚氨酯(WPU)胶膜力学性能和耐水性较为优异,用N330和C.O.交联改性的胶膜手感很好,耐热性能也较好,用PER交联改性的胶膜力学性能有所提高,但耐水性能和耐热性能较未改性前反而有所降低。     

端羟基聚丁二烯改性水性聚氨酯的合成与性能

以端羟基聚丁二烯(HTPB)、聚醚二元醇(N-220)、异佛尔酮二异氰酸酯(IPDI)为主要原料,制备了改性水性聚氨酯(WPU)。研究了端羟基聚丁二烯(HTPB)的含量对聚氨酯乳液粒径、贮存稳定性,以及对涂膜耐水性、力学性能、低温柔韧性的影响。结果表明:在预聚反应中,固定总n(—NCO)∶n(—OH)为1.3,w(DMPA)为6%,HTPB添加量在40%(占聚醚N-220的量)以下时,粒径变化不大,乳液稳定性较好;针对不同HTPB添加量,控制好亲水基团的含量,可以获得分散性良好、贮存稳定的聚氨酯乳液;随着HTPB添加量逐渐增大,涂膜的拉伸强度逐渐增大后变小,断裂伸长率和吸水率逐渐减小后变大,低温柔韧性变好。当HTPB添加量在30%左右,涂膜的综合性能最佳。     

有机硅改性磺酸/羧酸型水性聚氨酯的研究

以聚醚多元醇(N-210)和2,4-甲苯二异氰酸酯(TDI)为原料,以自制的磺酸型亲水单体1,2-二羟基-3-丙磺酸钠(DHPA)和二羟甲基丙酸(DMPA)为扩链剂,采用氨丙基三甲氧基硅烷和氨乙基氨丙基三甲氧基硅烷对纯水性聚氨酯(WPU)进行改性,并对有机硅改性WPU胶膜的性能进行了研究。结果表明:WPU分别经两种不同结构的有机硅改性后,其胶膜的力学性能略高于未改性WPU,但耐水性和耐热性则明显高于未改性WPU。     

羟基硅油改性水性聚氨酯的制备与性能研究

以羟基硅油（PDMS）、二苯基甲烷二异氰酸酯（MDI）、聚醚多元醇为主要原料,合成了有机硅改性的水性聚氨酯（WPU）材料,探讨了PDMS用量对WPU乳液和胶膜性能的影响,并采用FT—IR和DSC对其进行了表征。结果表明,随着PDMS加入量的增加,乳液粒径增大,粘度升高,胶膜的吸水率降低,力学性能和热稳定性提高。当PDMS质量分数为11．8％时,制备的有机硅改性聚氨酯材料性能最佳,其吸水率下降至5．6％,拉伸强度达到14．74MPa,断裂伸长率为462％,胶膜的初始分解温度提高了36℃。     

纳米SiO_2改性水性聚氨酯乳液的制备及性能研究

以硅烷偶联剂(KH-550)作为纳米二氧化硅(nano-SiO2)的表面处理剂,以甲苯二异氰酸酯(TDI)、聚醚二元醇(N-220)、二羟甲基丙酸(DMPA)和nano-SiO2等为主要原料,制备nano-SiO2改性WPU(水性聚氨酯)乳液。着重探讨了DMPA的加料方式、DMPA和nano-SiO2用量等对WPU乳液稳定性、粒径分布、耐水性和力学性能等影响。结果表明:采用先加入DMPA后扩链的加料方式,可制得外观及稳定性均较好的WPU乳液;当w(DMPA)=5%、w(改性nano-SiO2)=2.0%时,WPU乳液及其胶膜的综合性能较好。     

水性聚氨酯织物涂层剂合成与性能的研究

以IPDI、聚醚220、蓖麻油、DMPA等原料合成了系列水性聚氨酯涂层剂,研究了水性聚氨酯涂层剂NCO／OH比值、交联度、有机硅改性、有机氟改性等对涂层胶膜强度、手感、耐水压等性能的影响。研究表明,NCO／OH比值越高,胶膜强度越大,本实验合成的涂层剂耐水压随之降低。交联度越大,耐水压越高。蓖麻油的加入对提高耐水压和改善手感都有很大帮助,有机硅和有机氟的改性对提高耐水压和改善手感也有帮助。     

水性聚氨酯织物涂层剂合成与性能的研究

以IPDI、聚醚220、蓖麻油、DMPA等原料合成了系列水性聚氨酯涂层剂,研究了水性聚氨酯涂层剂NCO/OH比值、交联度、有机硅改性、有机氟改性等对涂层胶膜强度、手感、耐水压等性能的影响。研究表明,NCO/OH比值越高,胶膜强度越大,本实验合成的涂层剂耐水压随之降低。交联度越大,耐水压越高。蓖麻油的加入对提高耐水压和改善手感都有很大帮助,有机硅和有机氟的改性对提高耐水压和改善手感也有帮助。     

Ca~(2+)含量对水性聚氨酯乳液及其胶膜性能的影响

以甲苯二异氰酸酯(TDI)、聚醚(N-210)、二羟甲基丙酸(DMPA)和一缩二乙二醇(DEG)等为主要原料,合成了自乳化型WPU(水性聚氨酯)乳液;然后以氢氧化钙作为交联改性剂,通过Ca2+与-COOH之间形成的螯合交联,制成Ca2+改性WPU乳液。结果表明:当n(Ca2+)∶n(-COOH)=0.4∶1时,改性WPU乳液具有较好的储存稳定性和综合性能,其胶膜的热性能、耐水性、剥离强度(4.5 N/mm)、拉伸强度(14.5 MPa)和断裂伸长率(454.5%)等均相对较高。     

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。