用SRC、ACR、MBS、CPE改性生产的PVC透明制品性能对比

对分别用改性剂SRC、ACR、MBS、CPE生产的PVC透明制品进行了性能检测,结果表明:①塑化性能:CPE＞SRC＞MBS＞ACR;②雾度性能:ACR＞SRC＞CPE＞MBS;③增强、增韧、冲击性能:MBS＞CPE＞SRC＞ACR.     

ACR树脂的生产技术概况及其发展动态

ACR树脂是由甲基丙烯酸甲酯、丙烯酸丁酯经种子乳液聚合得到的热塑性接枝聚合物．主要用作PVC硬制品的抗冲改性剂，可以改善PVC制品的抗冲击性能和其加工性能。本文介绍了PVC抗冲改性剂ACR树脂的国内外生产概况，阐述了ACR树脂的技术概况，并分析了国内有关ACR树脂生产、技术、市场和价格等方面的一些发展动态。     

抗冲击型ACR中试生产技术研究

采用乳液聚合技术,将实验室中的抗冲击型ACR实验结果扩大到中试,选择合理的生产方法和适宜的工艺条件生产抗冲击型ACR。按照国家标准对添加抗冲击型ACR的PVC型材进行性能测试。试验结果表明,所生产的ACR能赋予PVC制品良好的抗冲击性。     

高抗冲ACR接枝VC共聚树脂的应用

比较了ACR接枝VC共聚树脂与CPE对PVC干混料加工性能、给水用PVC-U管材性能的影响。结果表明:①与CPE相比,ACR接枝VC共聚树脂可降低PVC干混料的平衡转矩,缩短塑化时间,节约能源消耗;②对于Φ32、Φ110给水用PVC-U管材,添加ACR接枝VC共聚树脂生产的PVC-U管材性能全部符合国家标准,且综合性能全部优于添加CPE生产的PVC-U管材。     

龙新抗冲ACR性能评价

目前用于PVC异型材生产的抗冲改性剂主要有：EVA、CPE和抗冲型ACR树脂等。其中抗冲ACR系列产品以其优异的增韧性、良好的耐热和成型加工性、以及在很宽的温度范围内保持最佳的冲击性能等优点而倍受关注。本文针对龙新抗冲ACR性能进行评价。     

ACR改性CPVC凝胶化测试及力学性能的研究

采用差示扫描量热法(DSC)和HAAKE流变仪研究了不同用量的抗冲型丙烯酸酯橡胶(ACR)改性氯化聚氯乙烯(CPVC)的凝胶化性能及流变性能,综合力学件能、耐热性能、微观形貌对ACR改性CPVC进行系统研究.结果表明,ACR的加入能极大地提高CPVC的凝胶化度,促进塑化,改善CPVC加工性能,ACR用量6～9份为宜,对CPVC的增韧效果较好.     

（甲基）丙烯酸酯类塑料加工改性剂

概述了(甲基)丙烯酸脂类塑料加工改性剂ACR的性能、生产状况及市场发展趋势，指出开发ACR是(甲基)丙烯酸(酯)化工的重要消耗取向。     

我国ACR发展概况

介绍了我国PVC改性剂ACR的生产、加工情况及对PVC性能的改进     

OFMA／MMA／VCM复合冲击改性剂的制备及其在PVC制品中的应用

通过在ACR聚合过程中加入含氟单体OFMA,从而将氟元素引到ACR聚合物的骨架上,同时用VCM代替部分丙烯酸丁酯（BA）,降低了ACR的成本,制备了性能优良的ACR冲击改性剂。最佳试验方案为：种子乳液的合成,m（MMA）：m（BA）=70：30的混合物为聚合性单体;核壳聚合时,取m（OFMA）：m（MMA）：m（VCM）=3：57：40。生产出的ACR样品抗冲增韧性能和加工流动性能最好,用于生产PVC样品,力学性能最好。     

MBS、ACR对CPVC凝胶化性能及其力学性能的对比分析

采用差示扫描量热法( DSC)分别测定了抗冲改性剂MBS、ACR对CPVC凝胶化性能的影响,综合力学性能、耐热性能对CPVC/MBS和CPVC/ACR共混物进行了系统研究.结果表明:MBS、ACR的加入均能极大地提高CPVC的凝胶化度,相同的改性剂含量下,共混物的凝胶化度差别不大;MBS、ACR均能大幅提高共混物的冲击强度,MBS用量3～6份、ACR 6～9份对CPVC的增韧效果较好,MBS为3～6份时共混物的性能更优,成本更低,但ACR的耐候性制品优于MBS的.     

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。