硅烷交联聚乙烯电力电缆绝缘料的研制

采用两步法制备了硅烷交联聚乙烯（PE）电力电缆绝缘料。以双螺杆挤出机为反应器,以低密度聚乙烯（LDPE）和线型低密度聚乙烯（LLDPE）为基础树脂,考察了影响PE接枝交联的主要因素（如基础树脂的配比,交联剂的用量及种类,引发剂、抗氧剂的用量等）,得出了具有良好性能的硅烷交联PE电力电缆绝缘料的配方（质量份数）：LDPE为85．00phr,LLDPE为15．0H0phr,硅烷W为0．60phr,硅烷Q为1．40phr,引发剂为0．12phr,抗氧剂为0．20phr。     

可剥离交联型EVA半导电绝缘屏蔽料的研制

采用混炼方法研究了基础树脂、导电材料、交联剂、润滑剂、抗氧剂对可剥离交联型EVA半导电绝缘屏蔽料性能的影响,确立乙烯-醋酸乙烯共聚物(EVA)半导电绝缘屏蔽料配方(质量份数):EVA为100份,导电炭黑为60份,交联剂为2.1份,润滑剂为8.0份,抗氧剂为0.8份.对产物性能的表征表明,该绝缘屏蔽料20 ℃体积电阻率为52.6 Ω·cm,剥离强度为18.4 N/cm,热延伸试验载荷下伸长率为75%.     

PP无纺布辐射接枝MMA的研究

采用聚丙烯(PP)无纺布为基材,甲基丙烯酸甲酯(MMA)为单体,~(60)Co-γ射线预辐射接枝共聚的方法制备接枝共聚物,讨论了辐射剂量、反应温度、反应时间、单体浓度、阻聚剂和交联剂的用量等对接枝率的影响。结果表明,接枝反应的最佳条件为:辐射剂量60 kGy以上、接枝温度65℃、接枝时间2 h、MMA质量分数20%、交联剂质量分数5%、阻聚剂用量0．3g,该条件下PP的接枝率为6．5%。     

反应挤出法制备LLDPE-g-(GMA-co-St)的研究

以甲基丙烯酸缩水甘油酯(GMA)为接枝单体,苯乙烯(St)为接枝共单体,在双螺杆挤出机上对线型低密度聚乙烯(LLDPE)进行熔融接枝,制备了LLDPE-g-(GMA-co-St).研究了引发剂用量、单体用量、共单体用量和抑交联剂亚磷酸三苯酯等对LLDPE接枝物接枝率和熔体质量流动速率的影响,利用红外光谱对接枝物进行了表征.研究表明,St的加入能有效提高GMA的接枝率,亚磷酸三苯酯有效抑制了LLDPE的交联.最佳配方为:过氧化二异丙苯(DCP)为0.15份,GMA为3份,St为3份,亚磷酸三苯酯为1份.     

给水用钢丝增强聚乙烯复合管道粘接树脂的研究

利用反应性接枝和物理共混两种技术,制备了一种适合于粘接聚烯烃树脂和金属铜的粘接树脂。主要研究了反应性接枝配方和物理共混配方对树脂粘接性能的影响。采用接触角、扫描电子显微镜、能谱等表征和测试手段,对最终的接枝树脂和粘接树脂的极性、粘接性能进行了研究。结果表明,聚乙烯接枝马来酸酐(PE-g-MAH)的最佳配方为:线型低密度聚乙烯90份,高密度聚乙烯10份,马来酸酐1.5份,过氧化二异丙苯0.08份,抗氧剂1010和抗氧剂168分别为0.2份。最高接枝温度为180℃。粘接树脂的最佳配方为:PE-g-MAH 100份,增粘树脂6份,调节剂15份。研制的粘接树脂具有和聚烯烃一样的加工性能和条件,同时表现出极佳的粘接性能,主要用于给水用钢丝增强聚乙烯复合管道。     

中国塑料专利

<正>专利名称:一种交联聚乙烯电缆绝缘材料申请公布号:CN103483662申请公布日:2014.01.01本发明提供一种交联聚乙烯电缆绝缘材料,其配方包括:低密度聚乙烯50~80份,聚丙烯10~30份,EVA树脂1~10份,交联剂1~7份,润滑剂4~16份,抗氧剂1~3份,助剂1~3份。所述低密度聚乙烯的相对分子量分     

钢塑复合管专用交联HDPE的研制

研制了钢塑复合管专用交联高密度聚乙烯(HDPE),并研究了其性能。结果表明．交联后的HDPE具有更加优异的力学性能;随着交联剂(VS—1)用量的增加,交联HDPE的拉伸强度、冲击强度、凝胶率增加,但其断裂伸长率和流动性下降,当VS—l质量分数为1．8％时,交联HDPE的性能最佳：拉伸强度为40．8MPa,冲击强度为117J／m^2,凝胶率为73．8％,断裂伸长率为280％,熔体流动指数为0．3g／10min;将5000S与2480共混,并添加质量分数不低于1．0％的流变剂YL—1,其加工流动性最佳;用二月桂酸二丁基锡作催化剂使HDPE的交联反应在5h后就完成了90％以上．比不加催化剂提前15h。     

过氧化物交联HDPE材料的研究

研究了交联用高密度聚乙烯(HDPE)的种类、交联剂二叔丁基过氧化物(DTBP)、助交联剂T的用量对交联HDPE复合材料结构和性能的影响。选用辛烯为共聚单体和支化度(每1000C中的甲基数)为3.2的HDPE为原料树脂,主交联剂DTBP和助交联剂T的质量分数分别为0.15%,0.20%时,材料的各项性能符合交联HDPE管材的要求。     

马来酸酐辐照接枝三元乙丙橡胶的研究

采用辐照技术,用马来酸酐(MAH)对三元乙丙橡胶(EPDM)进行接枝改性,测定接枝物的交联度和接枝率.分析了辐照剂量、马来酸酐用量以及阻交联剂用量对接枝物交联度和接枝率的影响.同时,采用正交试验优化了试验参数.结果表明,当辐照强度为0.3 kGy/h、辐照剂量为0.15 kGy、MAH与EPDM的质量比为0.025:1以及阻交联剂的质量分数为0.02%时,接枝率达到1.35%.     

辐照交联聚乙烯管材专用树脂的研制

通过对辐照交联管材基体树脂及助剂体系的配方研究,讨论了敏化剂品种、用量及抗氧剂用量对体系交联度的影响,确定了辐照交联管材专用树脂的最佳配方,即高密度聚乙烯(6366M)和线形低密度聚乙烯(7042)的配比为80/20,敏化剂M-1和抗氧剂的加人量分别为2.5%和2.5%。还考察了辐照剂量对体系力学性能及结晶度的影响。结果表明:随着辐照剂量的增加,拉伸强度、断裂伸长率下降,材料发生交联的同时也发生了降解。随着辐照剂量的增加,结晶度基本没有发生变化,这说明交联只是发生在非晶区或晶区与非晶区的边缘。加工应用实验表明,专用树脂的各项性能达到进口树脂ME2592的水平。     

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。