利用粉体助剂制备高抗冲聚丙烯的表征

利用粉体助剂的特殊表观性能,将其引入到丙烯聚合反应体系,显著提高了高抗冲聚丙烯颗粒的流动性,得到了高抗冲聚丙烯颗粒,对所得产品进行表征。结果发现,颗粒表面均匀地分布着粉体助剂,产品乙烯质量分数可达22.10%,橡胶相含量可达33.1%,简支梁低温冲击强度为14.10 kJ/m²同时能保持较好的刚性。利用¹³CNMR对产品进行分析,明确了所得产品的序列结构。     

BR/EVA/HIPS TPV的制备和性能研究

采用苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)改善BR/乙烯-乙酸乙烯酯共聚物(EVA)/高抗冲聚苯乙烯(HIPS)共混物的界面相容性,通过动态硫化法制备BR/EVA/HIPS TPV,并对其性能进行研究.结果表明:未加入SBS的BR/EVA/HIPS共混物未表现出橡胶类弹性体特征,而加入适量SBS的共混物表现出典型橡胶类弹性体特征;当SBS用量为8～12份时,BR/EVA/HIPS TPV的综合物理性能较好,拉伸断面平滑,界面相容性良好.     

聚丙烯抗冲共聚产品2500H的开发

采用反应器串联操作的方式,在气相反应器中聚合生成高抗冲的共聚聚丙烯2500H.结合Novolen聚丙烯工艺特点,通过试生产确定出生产工艺条件和反应物的性能：高抗冲共聚聚丙烯的MFR为1.5-2.5 g·（10min）-1,乙烯含量为9％～13％,二甲苯可溶物含量为18％～23％,产品低温抗冲击性能优良.     

高性能乙华平（EVM）橡胶的特性及应用

1　前言乙华平橡胶是乙烯和醋酸乙烯的共聚物。其化学名称为乙烯醋酸乙烯橡胶 ,简称 EVM。乙华平是德国拜耳公司生产的该种橡胶的注册商标 ,在中国已有销售。乙华平橡胶属于特种橡胶 ,它在耐高温( 175°C) ,耐油 (相当于丙烯腈 ACN含量 2 6-34 %的丁腈橡胶 ) ,耐天候老化 (仅次于EPDM)以及阻燃方面都非常优秀。近年来在电缆、胶辊、家用电器及汽车橡胶配件等产品上的应用非常广泛 ,已经成为某些特殊橡胶产品所不可取代的新型原材料。2　乙华平橡胶的商品牌号商品牌号 VA% 门尼粘度ML(1 4) 1 0 0°C熔融指数MFI 1 90 /21 6KP(g/1 0…     

抗冲聚丙烯的结构与性能

用FTIR,Cryst-EX对MFR相近的两种市售抗冲聚丙烯结构与性能进行表征,发现乙烯含量更低的进口产品常温和低温抗冲击性能更佳。通过分析认为,乙烯链段在聚丙烯链上分布更加均匀,能生成更多的橡胶相,所以产品抗冲性能更好,综合性能更优。其中,国产料MFR为34.1 g/10 min,乙烯质量分数为11.3%,橡胶相含量为19.7%,橡胶相中乙烯含量为36.9%,常温简支梁冲击强度为11.2 k J/m2,低温简支梁冲击强度为6.5 k/m2。进口料MFR为33.2 g/10 min,乙烯质量分数为9.2%,橡胶相含量为27.7%,橡胶相乙烯含量为26.2%,常温简支梁冲击强度为15.3 k J/m2,低温简支梁冲击强度为7.5 k J/m2。     

高流动高刚抗冲共聚聚丙烯聚合工艺与结构和性能关系研究

采用两步法在Spheripol聚丙烯中试装置进行高流动高刚抗冲共聚聚丙烯中试开发，获得三种刚韧平衡的中试产品。对产品进行力学性能、乙烯含量、橡胶相含量、DSC测试，采用偏光显微镜（POM）、扫描电子显微镜（SEM）对结晶及脆断面形貌进行观察。结果表明：提高产品中乙烯含量、降低气相反应器中气相比和氢气/乙烯比、提高橡胶相的分子量、细化橡胶相尺寸、改善橡胶相的分散性，均有利于提高产品的冲击强度。降低橡胶相含量、细化球晶尺寸、提高产品结晶度，尤其是均聚部分的结晶度有利于提高产品刚性。降低中试气相比，将产品的乙烯含量控制在4.5%左右，橡胶相含量为9.5%左右，橡胶相尺寸为0.5μm左右，可获得刚韧平衡的高流动高刚抗冲共聚聚丙烯产品。     

高抗冲聚苯乙烯体系中橡胶相的粒径及其控制

在高抗冲聚苯乙烯(HIPS)体系中,橡胶相的粒径一般在0.5微米以上。若橡胶相的形态基本上保持圆形,并具有适当的交联度,则橡胶相的粒径对熔融指数和加工性能影响不大,但对抗冲强度和制件外观有较大的影响。在一般情况下,橡胶相的种类及数量、树脂的分子量及其分布都是确定的,因此抗冲性能则主要取决于橡胶相的粒径大小。     

抚顺石化研发聚丙烯纤维料

<正>近日,抚顺石化开发出应用广泛、附加值高的高熔融指数聚丙烯(PP)纤维树脂L5D49,目前装置以35 t/h的负荷稳定生产。该公司烯烃厂30万t/a PP装置采用美国Uniplo气相法生产工艺,可生产均聚、无规共聚和乙烯含量17%的产品。在装置开车的一年多时间里,技术人员在该装置上已成功开发出应用于洗衣机缸体、汽车的高橡胶含量抗冲PP LC7749-35N等多个牌号PP产品。为进一步发挥装置的技术优势,增产高附加值     

聚丙烯超高抗冲共聚产品SP179生产和微观分析

通过确定气相反应器中的乙烯/乙烯+丙烯和氢气/乙烯的组分,生成较多的乙丙橡胶,使聚丙烯抗冲共聚产品SP179具有较高的抗冲强度.通过对产品的微观分析,指出橡胶相含量、乙烯含量、平均橡胶粒子粒径、橡胶粒子分散情况是影响产品冲击强度的因素.     

抗冲共聚聚丙烯在Novolen装置上的生产

对Novolen工艺中抗冲共聚聚丙烯生产的共聚反应机理、产品质量控制原理、工艺调节措施进行了综述。影响抗冲共聚物产品质量的主要因素有均聚物MFR、粉料总MFR、乙烯总含量和橡胶相中乙烯含量。只有对每个影响因素进行仔细选择和控制才能得到高质量的抗冲共聚聚丙烯产品。此外,以抗冲共聚聚丙烯2500H生产为例,对抗冲共聚聚丙烯产品的生产过渡步骤进行了研究,并对得到的产品进行了分析讨论。     

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。