聚丙烯/改性高岭土复合材料的制备及性能表征

采用乙酸钾插层改性高岭土后,与十八胺共混球磨制得表面疏水的插层改性高岭土,再与聚丙烯(PP)熔融共混制得聚丙烯/改性高岭土复合材料。采用傅里叶变换红外光谱(FTIR)、X射线衍射仪(XRD)对改性高岭土进行表征;扫描电镜(SEM)、透射电镜(TEM)、拉力机和热重分析仪分别对复合材料的表面形貌、力学性能和热学性能进行测试。结果显示,插层改性后高岭土d001为1.42 nm,增加0.7 nm,插层率达到79.65%;改性高岭土片层较均匀分散在聚丙烯基体中,随着改性高岭土的添加量的增加,复合材料力学性能和热稳定性均明显改善,当改性高岭土的填充量为7%时复合材料的拉伸强度比纯PP增加34.22%,断裂伸长率增加29.33%。     

PC/改性ABS复合材料的制备与性能

在传统的丙烯腈-丁二烯-苯乙烯共聚物(ABS)乳液接枝聚合中加入甲基丙烯酸甲酯(MMA),制得了改性ABS,然后与聚碳酸酯(PC)共混挤出，制得了PC/改性ABS复合材料。研究了MMA用量对PC/改性ABS复合材料的熔体流动速率(MFR)、维卡软化温度、力学性能的影响。结果表明：随着MMA用量的增加，PC/改性ABS复合材料的MFR、拉伸强度、弯曲强度和缺口冲击强度均先升高后降低。当MMA质量分数为20%时，PC/改性ABS复合材料的拉伸强度和弯曲强度均达到最大，分别为48.9 MPa和63.2 MPa;当MMA质量分数为30%时，PC/改性ABS复合材料的缺口冲击强度为41.0 kJ/m²;当MMA质量分数不高于30%时，与PC/ABS复合材料相比，PC/改性ABS复合材料的维卡软化温度更高。     

柠檬酸改性β型分子筛在膨胀阻燃ABS复合材料中的协同作用研究

采用浸渍法制备了柠檬酸改性的β型分子筛(N-β)。红外光谱测试表明,柠檬酸对β型分子筛具有补铝作用,可使其骨架铝含量增加。利用热重分析、氧指数测试、扫描电镜分析等手段探讨了N-β对丙烯腈-丁二烯-苯乙烯共聚物(ABS) /膨胀型阻燃剂(IFR)复合材料热失重行为、阻燃性能、微观结构及力学、加工性能的影响。结果表明,N-β在含量较低时与IFR具有较好的阻燃协同作用,可促进IFR高温成炭,形成稳定、连续、致密的炭层结构。当N-β量为2%(质量分数,下同)时,ABS/IFR复合材料的极限氧指数为31.3%,残炭量为24. 86%。同时,随着N-β含量的增加,复合材料的冲击强度、拉伸强度呈现出先升后降的趋势。     

废旧丁腈橡胶粉和空心玻璃微珠改性丙烯腈-丁二烯-苯乙烯共聚物复合材料的研究

采用废旧丁腈橡胶粉(WNBR)和硅烷偶联剂改性的空心玻璃微珠(HGB)对丙烯腈-丁二烯-苯乙烯共聚物(ABS)改性,分别研究WNBR和改性HGB用量对WNBR/ABS和改性HGB/WNBR/ABS复合材料结构和性能的影响。结果表明:在WNBR/ABS复合材料中,WNBR用量较小时,WNBR粒子与ABS基体相容性较差,界面结合力较弱;WNBR用量为20份时,WNBR和ABS相容性较好,断面较平整光滑。WNBR可以降低复合材料的拉伸强度和弯曲强度,提高冲击强度。在改性HGB/WNBR/ABS复合材料中,改性HGB呈单分散状,没有团聚,分布比较均匀。改性HGB在用量低于5份时可以同时提高改性HGB/WNBR/ABS复合材料的拉伸强度、弯曲强度和冲击强度,用量为5份时复合材料的综合物理性能最佳。     

PP/纳米有机高岭土复合材料的制备及性能

以二甲基亚砜(DMSO)改性的高岭土作前躯体,采用熔融插层法制备聚丙烯(PP)/纳米有机高岭土复合材料.采用FTIR、XRD、SEM等方法对其结构与形态进行表征,结果表明:聚丙烯已成功进入到高岭土片层间,层间距扩大到1.123 nm,插层率为73%;性能测试结果表明:改性高岭土的加入在不同程度上提高了PP的冲击性能和热性能.     

芳纶1414增强ABS复合材料的性能研究

用短切芳纶1414(PPTA)对丙烯腈-丁二烯-苯乙烯共聚物(ABS)树脂进行增强改性,利用扫描电镜、热失重分析和力学性能测试等方法分析了ABS/PPTA复合材料的断面形态结构、热性能和力学性能。结果表明:当PPTA用量为5份时,ABS/PPTA复合材料的拉伸强度和拉伸模量分别比纯ABS树脂提高了11%和29%,弯曲强度和弯曲模量分别增至78.8MPa和2.9GPa;PPTA可增强ABS树脂在高温时的热稳定性,降低最大失重速率并,提高残炭量。     

适用于3D打印技术的ABS/SEBS复合材料制备

采用热塑性弹性体苯乙烯–乙烯–丁烯–苯乙烯嵌段共聚物(SEBS)对丙烯腈–丁二烯–苯乙烯塑料(ABS)进行改性,制备3D打印ABS/SEBS复合材料,研究了SEBS的用量对3D打印ABS/SEBS复合材料流动性能、力学性能与热降解行为的影响。结果表明,随SEBS用量的增加,ABS/SEBS复合材料的熔体流动速率先增加后降低;随SEBS用量增加,ABS/SEBS复合材料的冲击强度增加,SEBS能提高ABS/SEBS复合材料的断裂伸长率,但同时也使拉伸强度和弯曲强度降低;随SEBS用量的增加,ABS/SEBS复合材料的热稳定性增加;当SEBS质量分数为15%时,ABS/SEBS复合材料在3D打印中的综合性能最好。     

无卤阻燃ABS/TPU复合材料阻燃性能的研究

采用了微胶囊红磷(MRP)、氢氧化镁(MH)、聚硅氧烷组成复合阻燃剂,对丙烯腈-丁二烯-苯乙烯(ABS)/热塑性聚氨酯(TPU)合金进行改性,获得了环保型阻燃ABS/TPU复合材料。对该复合材料进行了阻燃性能、热稳定性测试和炭层形貌分析。结果表明,当复合阻燃剂MRP/MH质量比为1/1且添加量为16份时,复合材料的极限氧指数(LOI)为25.7%,垂直燃烧性能通过FV-0级;TPU结构中因含氧,有利于MRP/MH阻燃体系阻燃;添加6份聚硅氧烷,复合材料垂直燃烧级别达到FV-0级,聚硅氧烷燃烧过程中通过改变炭层形貌,提高阻燃性。     

ABS回料/SB/DMMT复合材料的结构与性能

制备了苯乙烯-丁二烯塑料(SB)/双改性蒙脱土(DMMT)杂化物,并以其增韧增强丙烯腈-丁二烯-苯乙烯塑料(ABS)回料,研究了ABS回料/SB/DMMT复合材料的结构与性能。结果表明,随着SB/DMMT(70/30)杂化物用量的增加,复合材料的缺口冲击强度、拉伸强度和弯曲强度呈先增加后降低的趋势,在杂化物用量为10份时达到最大值,其力学性能和热稳定性明显高于ABS回料。透射电子显微镜和X射线衍射仪的测试结果显示,ABS回料/SB/DMMT复合材料属于插层结构与剥离结构共存的纳米复合材料。     

专利

<正>本发明涉及聚氨酯-纳米高岭土复合材料的制备方法。该复合材料主要由聚氨酯、纳米高岭土组成,先将纳米高岭土进行有机插层改性以获得层间距较大的有机改性纳米高岭土,然后采用本体-原位插层聚合法制备聚氨酯-纳     

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。