静态混合技术制备橡胶输送带用喷涂聚氨酯(脲)弹性体的研制

研制适合橡胶输送带使用的喷涂聚氨酯(脲)弹性体,拓展喷涂聚氨酯(脲)弹性体的应用领域,解决当前喷涂设备成本高及小面积施工困难的需求。以不同种类的聚醚多元醇与二甲苯甲烷二异氰酸酯(MDI-50)合成预聚物为A组分,聚醚多元醇及胺基扩链剂为B组分,采用静态混合技术制备喷涂聚氨酯(脲)弹性体。通过研究异氰酸酯(—NCO)含量、聚醚多元醇种类、扩链剂种类与用量等因素,对聚氨酯(脲)弹性体凝胶速度、硬度、拉伸强度、断裂伸长率、耐磨性等性能的影响,成功研制出适合橡胶表面使用的喷涂聚氨酯(脲)弹性体产品,并对该产品进行物理性能及耐介质性能测试。     

手机抛光轮用聚氨酯微孔弹性体的研究

采用聚醚多元醇、聚合物多元醇、自制聚醚酯多元醇和二乙醇胺等助剂配制A组分,由聚醚多元醇EP-3600或MN-3050与MDI系异氰酸酯合成半预聚体(B组分),在A组分中加入40%轻质碳酸钙混合后与B组分按照一定比例混合制备了一种用于手机抛光轮的聚氨酯微孔弹性体,研究了聚醚酯多元醇加入量、交联剂用量、合成半预聚体所用聚醚、异氰酸酯指数、泡沫密度对抛光轮性能的影响。结果表明,在主体聚醚中聚醚酯多元醇的质量分数为20%、二乙醇胺为主体聚醚的2%、B组分用EP-3600合成、异氰酸酯指数为1.03时,制得的密度为0.35~0.40 g/cm3的聚氨酯微孔弹性体抛光轮能够满足现场对手机壳打磨的要求。     

不同合成工艺的聚醚多元醇对聚氨酯弹性体性能的影响

分别采用低不饱和度聚醚多元醇DL-1000D和氧氧化钾体系聚醚多元醇DL-1000与TDI-80反应合成出聚氨酯预聚体,比较了2种不同聚醚多元醇合成预聚体的工艺性能、预聚体的稳定性和由它们合成聚氨酯弹性体制品的力学性能和耐磨性能。结果表明,二者的丁艺性能和稳定性相当,采用前者合成的聚氨酯弹性体的力学性能比后者高10％左右,耐磨性能按阿克隆磨耗测试提高17．6％。     

聚脲弹性体材料耐磨性能的探讨

由不同二元醇与二异氰酸酯合成不同NCO含量的半预聚体(A组分)与端氨基聚醚、胺扩链剂等原料组成的R组分经喷涂设备喷涂成型聚脲弹性体。讨论了在不同摩擦工况下NCO含量、异氰酸酯指数、预聚物类型、耐磨助剂等对聚脲弹性体耐磨性能的影响。结果表明,不同NCO含量在不同摩擦工况下对聚脲耐磨性能的影响不同,干摩擦工况下NCO含量越高,耐磨性能越佳,湿摩擦工况下则是NCO质量分数为15%耐磨性最佳,异氰酸酯指数对聚脲耐磨性能的影响较小,使用聚四氢呋喃二元醇、TDI预聚物和耐磨助剂,可提高不同摩擦工况下聚脲的耐磨性能。     

静态混合技术制备喷涂聚氨酯(脲)弹性体

以不同种类的多元醇与二苯基甲烷二异氰酸酯(MDI-50)合成预聚物作为A组分,端胺基聚醚或多元醇、胺类扩链剂为R组分,制成聚氨酯(脲)弹性体。讨论了多元醇种类对A组分黏度的影响,B组分中端胺基聚醚和多元醇对凝胶时间的影响,A、B组分中多元醇种类凝胶时间和物理性能的影响。     

高强喷涂聚氨酯（脲）弹性体的研制

喷涂聚脲弹性体技术近几年来得到高速发展,但纯聚脲的昂贵价格制约了该技术的大规模应用.从市场需求出发,采用聚醚多元醇、端氨基聚醚和扩链剂等制备了一种高性能、低成本的喷涂聚氨酯(脲)弹性体,其拉伸强度18.85 MPa,断裂伸长率440%,撕裂强度85 N/mm,适用于防水、防腐、耐磨领域.     

室温固化低硬度聚氨酯模具胶的合成及性能研究

制备了一种在室温条件下固化的低硬度、可用于模具胶的聚氨酯弹性体。研究了B组分中的聚醚多元醇种类、扩链剂种类、催化剂种类、增塑剂添加量以及异氰酸酯指数对制备的聚氨酯弹性体性能的影响。结果表明:B组分中的聚醚多元醇为PPG–2000,扩链剂为MOCA,催化剂为自制的MX–2,增塑剂用DOP且w(DOP)为10%,异氰酸酯指数为1.05时,原料成本较低,可操作性好,所制得的聚氨酯弹性体综合性能优异。     

养殖场用耐磨蓖麻油聚氨酯防水涂料的研制

以聚醚多元醇、二苯基甲烷二异氰酸酯、蓖麻油为主要原料制备聚氨酯预聚体(A组分),以无机填料CaCO3、扩链剂MOCA、氯化石蜡、溶剂油等配制B组分,制备用于养殖领域的双组分耐磨聚氨酯防水涂料。研究了预聚体NCO含量、蓖麻油用量、无机填料和扩链剂用量对聚氨酯涂膜性能的影响。结果表明,当A组分中NCO质量分数8.1%、蓖麻油质量分数10%,B组分中MOCA质量分数11%、填料用量为40%时,所制备的耐磨型聚氨酯防水涂料性能最优且成本合理。该涂料施工方便,能满足养殖领域对防水材料的要求。     

SPUA—102喷涂聚脲弹性体耐磨材料的研制

以MDI、液化MDI、聚醚多元醇、端氨基聚醚及肢类扩链剂等为原料,研制了一种喷涂型耐磨聚脲弹性体SPUA-102。对预聚体配方成分及NCO含量与粘度的关系、NCO含量对涂层的硬度、胺基组分配方对凝胶时间的影响,以及对如何提高耐磨性、耐介质性等问题进行了研究及探讨。     

低不饱和度聚醚多元醇制备聚氨酯弹性体

以甲苯二异氰酸酯、3,3‘－二氯－4,4‘－二氨基二苯基甲烷（MOCA）以及高相对分子质量、低不饱和度聚氧化丙烯多元醇为原料,以预聚体法制备了浇注型聚氨酯弹性体。比较了高相对分子质量、低不饱和度聚醚与普通聚醚在制备浇注型聚氨酯弹性体过程中的加工性能以及弹性体的物理性能。结果表明,与普通聚醚相比,低不饱和度聚醚制得的聚氨酯预聚体粘度较低,流动性较好,釜中寿命长,脱模时间短;制备的硬度为邵A83－95的浇注型聚氨酯弹性体,在硬度相同时,基于低不饱和度聚醚的弹性体的拉伸强度、伸长率、撕裂强度比基于普通聚醚多元醇制备的弹性体高20％－50％。     

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。