螺杆组合对PBT增强阻燃材料的性能影响

选用相同工艺同等长度不同组合的双螺杆加工PBT增强阻燃材料,测试并比较其各项性能。测试结果表明优化后的螺杆组合能够有效的提高共混物的各项力学性能。其中拉伸强度、弯曲强度、无缺口冲击强度和缺口冲击强度分别提高了44%、42%、39%和13%。     

螺杆组合设计对玻纤增强聚丙烯性能的影响

通过对比力学性能、拉伸性能及冲击样条断面形貌的变化,研究了螺杆组合改变对玻璃纤维(简称玻纤)增强聚丙烯(PP)性能的影响。结果表明:玻纤引入口至真空排气口之间的螺杆元件组合对玻纤增强PP性能的影响十分明显。由正输送元件、捏合元件、反输送元件组合改造成剪切捏合螺杆组合,提高了玻纤增强PP的拉伸强度、弯曲强度、弯曲模量和缺口冲击强度。     

耐高温高湿增强阻燃PBT复合材料的性能研究和优化

研究了不同聚对苯二甲酸丁二醇酯(PBT)树脂、阻燃剂、增韧剂和玻璃纤维种类对增强阻燃PBT复合材料在85℃、85%湿度条件下1000 h后的缺口冲击强度、拉伸强度和弯曲强度性能的影响。结果表明，使用PBT GX112J、BEO2025K、AX8900和ECS13-03-534AYF03作为主要配方体系，可以制备出耐高温高湿性能优良的增强阻燃PBT复合材料，此材料在85℃、85%湿度条件下1000 h后的缺口冲击保持率为91.8%；拉伸强度保持率为94.0%；弯曲强度保持率为93.5%。     

研制高冲击强度的增强PA66材料

探讨了增韧剂、玻纤种类和螺杆组合对玻纤增强PA66冲击性能的影响。研究结果表明,加入增韧剂能够有效提高玻纤增强PA66的冲击性能,当增韧剂用量为3%时,材料具有最优的冲击强度和缺口冲击强度。特殊偶联剂处理的玻纤和合适的螺杆组合有助于玻纤在树脂基体中获得均匀分散和较窄的长度分布,并提高组分间的界面作用,得到冲击性能优异的玻纤增强PA66材料。     

注塑工艺对LGFPP力学性能的影响

研究了注塑工艺对长玻纤增强聚丙烯（LGFPP）力学性能的影响。结果表明:螺杆转速对LGFPP玻纤残余长度(L_GF)和力学性能影响非常大,随着螺杆转速的增加,L_GF值下降,最终稳定在1.49 mm;拉伸强度、冲击强度和弯曲强度均随着螺杆转速的增加先上升后下降,当螺杆转速为60 r/min时,拉伸强度达到105 MPa,冲击强度和弯曲强度分别为28kJ/m²和180 MPa;背压对LGFPP的力学性能也有一定影响,但程度远小于螺杆转速的。     

玻纤增强阻燃PA6复合材料的制备与研究

从磷-氮系阻燃剂、阻燃剂类型、协效阻燃剂三个方面制备和研究了高冲击强度、高阻燃性能的玻纤增强阻燃尼龙6(PA6)复合材料。结果表明:三种方法都可以达到阻燃V-0;在溴-锑阻燃基础上,添加磷-氮系阻燃剂,可以提高玻纤增强阻燃PA6的阻燃性,但是会降低力学性能;红磷阻燃制备的复合材料的冲击性能最好;溴-锑阻燃制备的复合材料的拉伸强度和弯曲强度最高,冲击性能最低;有机次膦酸盐制备的复合材料的拉伸强度和弯曲强度最低,冲击性能适中;协效阻燃剂可以降低溴-锑的含量,降低材料成本,阻燃性能保持不变,拉伸强度和弯曲强度略有下降,冲击性能略有上升。得出如下结论:红磷阻燃剂质量分数是6%,以及F2400∶三氧化二锑∶协效阻燃剂质量分数比=17∶5∶2时,玻纤增强阻燃尼龙6复合材料的冲击性能最好,阻燃性达到UL94(1.6 mm)V-0。     

PBT材料缺口敏感性的探讨

研究了聚对苯二甲酸丁二醇酯(PBT)树脂、玻纤增强PBT树脂和矿物填充增强PBT树脂体系的缺口敏感性,分别通过缺口拉伸强度和缺口冲击强度来评估低频作用力和高频作用力下不同组分对PBT树脂缺口敏感性的影响。研究发现,PBT树脂的黏度和结晶性会严重影响PBT树脂的缺口敏感性,而玻纤的加入会提高PBT的抗缺口能力,矿物填充会严重增加PBT树脂的缺口敏感性。研究的几种不同的PBT体系中,缺口对强度的影响均大于对韧性的影响;缺口对高频作用力下韧性的影响大于低频作用力下韧性的影响。     

玻纤增强SAN材料力学性能的影响因素

通过对玻纤增强SAN树脂(SAN/GF)的力学性能分析,研究了影响玻纤增强SAN材料的因素。结果表明,添加SMA相容剂有助于增加SAN树脂与玻纤的界面结合强度,提高材料的力学性能,相容剂含量为3%时,增强材料的拉伸强度和弯曲强度分别达到117.2和140.2 MPa,比未加相容剂时,强度分别增加22.8%和12.8%。适量润滑剂的添加对提高材料力学性能具有正面效应,根据实验研究,润滑剂用量在0.2%时,玻纤增强材料性能较好。单丝直径为13和14μm的2种玻纤的增强效果差别不大,制备的增强材料的拉伸强度都在115 MPa以上,弯曲强度大于135 MPa。主机螺杆转速对玻纤增强SAN材料的力学性能影响不大。玻纤含量在20%时,制备的玻纤增强材料的冲击性能最好,达到5.7 kJ/m~2。     

高机械性能无卤阻燃PBT复合材料的制备

采用高效无卤阻燃剂CJ-1002、玻璃纤维、马来酸酐接枝乙烯辛烯共聚弹性体(POE-g-MAH)对聚对苯二甲酸丁二醇酯(PBT)进行阻燃及力学改性,研究了加工工艺对复合材料性能的影响。实验表明,PBT、阻燃剂、玻纤、POE-g-MAH的质量比为48/18/30/4时,复合材料在阻燃级别达到V-0的同时,拉伸强度、弯曲强度以及缺口冲击强度较改性前都有比较大的提升。     

一种新型相容剂对PBT/GF复合材料力学性能的影响

研究了国内一种新型相容剂甲基丙烯酸缩水甘油酯-苯乙烯-丙烯腈共聚物(SAG-008)对玻纤增强聚对苯二甲酸丁二醇酯(PBT)复合材料的力学性能影响,并用扫描电镜(SEM)对复合材料的界面相容性进行了研究。SEM表明,SAG-008有助于复合材料界面黏结。进一步和国外相容剂乙烯-丙烯酸甲酯-甲基丙烯酸缩水甘油酯共聚物(AX8900)进行比较,结果表明,SAG-008可以有效地提高玻纤增强PBT的拉伸强度、弯曲强度及缺口冲击强度;而AX8900对冲击强度改善明显。     

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.     

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。     

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.