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1.
制备了5种以烷氧基镁为载体的负载型BCM系列催化剂,粒径可在25.0~70.0μm调整,且用其制备的聚丙烯(PP)粉料的颗粒形态优良,流动性好。与NG型催化剂相比,BCM-100和BCM-200催化剂活性高20%以上且氢调敏感性相当,BCM-300催化剂活性高40%以上且不含邻苯二甲酸酯类化合物,BCM-400催化剂活性高50%以上且氢调敏感性好。与用NG型催化剂制备的PP(简称NG-PP)相比:用BCM-300催化剂所制PP的相对分子质量分布(Mw/Mn)宽30%;用BCM-400催化剂所制PP的Mw/Mn和重均分子量(Mw)都低约20%、等规指数接近98.0%、熔体流动速率(MFR)可达53.1 g/10 min,而NG-PP的MFR为22.0 g/10 min;用BCM-500催化剂所制PP的Mw高,Mw/Mn宽。  相似文献   

2.
从常规物性、流变性、加工稳定性等几个方面,对Innovene气相工艺氢调法生产的K9928H、降解法生产的K9928进行对比分析,结果表明:K9928H密度、常温冲击性、维卡软化点与K9928相接近,刚性、耐热性、加工性及外观颜色优于K9928,且气味低于K9928,但低温冲击性及光泽度略低于K9928。  相似文献   

3.
在200 kt/a气相法聚丙烯(PP)装置上采用氢调法成功开发了汽车内饰件专用高流动性抗冲击共聚PP YPJ-630H,考察了YPJ-630H的各项性能,并与用降解法生产的PP YPJ-630及进口同类PP的性能进行了对比。结果表明:YPJ-630H各项性能均达到设计指标要求,与YPJ-630和进口同类PP相比,YPJ-630H的冲击强度提高了5%~10%,相对分子质量分布更宽,加工性能更优,具有很强的应用潜力。  相似文献   

4.
通过差示扫描量热法研究了高流动高抗冲聚丙烯专用料K9928的非等温及等温结晶行为,并与国内市场典型牌号K7726H进行了对比分析。结果表明,K9928与K7726H的结晶度非常接近;K9928的起始结晶温度比K7726H高出3~5 ℃,低降温速率下的结晶速率较高,降温速率为50 ℃/min以上时,结晶温度区间较大;K9928内嵌段共聚物含量较多且组成相近,在韧性方面具有优势。  相似文献   

5.
以均聚聚丙烯(PP)为基础树脂,采用可控降解法生产了具有超高流动性的熔喷专用PP树脂RP1200,并通过了工业化应用试验。采用流变仪、凝胶渗透色谱仪、偏光显微镜及差示扫描量热仪对RP1200和进口同类树脂进行了对比研究。结果表明:RP1200与进口PP试样在相对分子质量及其分布、流变性能、微观结晶形态等方面较接近,但在结晶和熔融性能方面有较明显的差别;RP1200的结晶峰温度显著高于进口试样,且结晶峰较窄,即结晶速率更快;RP1200的熔融峰温度与进口试样较接近,但熔融峰较进口试样稍宽,说明其结晶完善程度的差异较大。在工业化应用中,RP1200的使用性能与进口PP树脂类似。  相似文献   

6.
将核磁序列分析法、傅里叶变换红外光谱法与聚合物流变学方法相结合,研究了典型的高流动抗冲共聚聚丙烯的相结构。结果表明:高流动抗冲共聚聚丙烯K9928和K7726H的乙烯-丙烯无规共聚物的结构非常接近;乙烯总含量不同导致乙烯-丙烯无规共聚物含量的差异,以及乙烯-丙烯嵌段共聚物含量和结构的差异;K9928和K7726H属于具有低共熔温度的共聚物,利用时温叠加原理流变学黏弹性评价方法可知,K9928的相分离温度较K7726H低,相同温度下,K9928较K7726H的相分离现象显著。  相似文献   

7.
通过分析高流动抗冲击共聚聚丙烯(PP)专用树脂的应用要求,确定PP K9928的乙烯质量分数需达到9.5%~11.5%,其橡胶相的乙烯质量分数需达到52.2%~56.3%。采用红外分析、升温淋洗分级、差示扫描量热法、凝胶渗透色谱法等分析了K9928的橡胶相含量、化学组成、熔融和结晶、长链立构规整性、相对分子质量及其分布等。结果表明:K9928的乙烯质量分数较高,达10.4%;丙烯高立构规整长序列含量较高,乙烯序列分布较为均匀;产品兼具良好的刚性和韧性。  相似文献   

8.
在500 kt/a的Novolen气相聚丙烯(PP)装置上进行PG型催化剂工业应用试验,生产均聚PP 1102K。考察了催化剂活性、聚合反应动力学及其与装置的适应性,并与进口催化剂进行了对比。采用凝胶渗透色谱法和差示扫描量热法等表征了分别用PG型催化剂和进口催化剂所制1102K的结构并研究了其性能。结果表明:PG型催化剂活性、氢调敏感性与进口催化剂接近,所制1102K粉料粒径分布集中、等规指数高;用这两种催化剂制备的1102 K的力学性能相当,微观结构基本一致。  相似文献   

9.
选择合适的基础树脂、降解剂,在国产第二代环管聚丙烯(PP)装置上采用可控流变工艺生产无纺布专用树脂。以熔体流动速率(MFR)为(6±1)g/10 min的PP粉料为基础树脂,采用降解剂B成功生产了MFR达(37±7)g/10 min的无纺布专用PP树脂H30S。产品应用试验表明:H30S等规指数大于96.0%,拉伸弹性模量大于1 200 MPa,性能指标优良,用户使用后反馈良好。  相似文献   

10.
通过熔融共混法制备聚丙烯/碳酸钙(PP/CaCO_3)复合材料。利用电子万能试验机、冲击试验机、差示扫描量热仪(DSC)和熔融流变仪等测试复合材料的熔体流动速率(MFR)、力学性能等。结果表明:在CaCO_3的添加量为5%时,MFR增加近20%,PP基体的加工流动性明显改善,复合材料的结晶度得到提升,材料的冲击强度最大,达到2.2 kJ/m~2,断裂为韧性断裂。加入适量的CaCO_3可以有效增强PP的综合性能。同时,将改性后的PP纤维应用于混凝土的增强,混凝土的弯曲承载力提高近24.14%。  相似文献   

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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.  相似文献   

13.
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.  相似文献   

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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.  相似文献   

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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.  相似文献   

19.
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。  相似文献   

20.
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.  相似文献   

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