粉末NBR和超细碳酸钙填充粉末NBR硫化胶力学性能的研究*

以高分子树脂膜为包覆剂,采用凝聚共沉法制备非填充型粉末ＮＢＲ和超细碳酸钙填充粉末ＮＢＲ。研究了包覆剂及超细碳酸钙的用量对产物粒径及其硫化胶力学性能的影响。结果表明,当包覆剂用量为１０份时,粒径≤０９ｍｍ的产物占９９８％,加入超细碳酸钙后可进一步减小产物的粒径;极性适宜的包覆剂及超细碳酸钙对粉末ＮＢＲ硫化胶有显著的补强作用,故非填充型粉末ＮＢＲ及超细碳酸钙填充粉末ＮＢＲ均有良好的力学性能。扫描电镜分析表明,极性适宜的包覆剂与ＮＢＲ有一定的相容性,并以粒径约０５μｍ的微粒均匀分布于ＮＢＲ基体中;超细碳酸钙则以原生粒子和粒径≤０５μｍ的团粒存在,它在粉末ＮＢＲ中的分散性比块状ＮＢＲ／超细碳酸钙混炼体系有显著改善     

超细碳酸钙填充粉末NR的制备及其硫化胶的力学性能

用高分子树脂作包覆剂、超细碳酸钙作填充剂,以凝聚共沉法制备了填充型粉末ＮＲ。研究了产物的粒径及其硫化胶力学性能的影响因素。结果表明,产物的粒径与包覆剂用量及超细央酸钙填充量有关,当包覆剂用量不小于２０份、超细碳酸钙填充量不小于１００份的,粒径不大于２．０ｍｍ的产物产率达９５％以上。在填充量相等的条件下,超细碳酸钙填充粉末ＮＲ硫化胶的力学性能比块状ＮＲ与超央酸钙机械混炼硫化胶有大幅度提高。ＳＥＭ分析     

高耐磨炉黑填充粉末丁腈橡胶的制备及性能

研究了利用高分子树脂凝聚包覆法制备高耐磨炉黑填充粉末丁腈橡胶的制备过程及其影响硫化胶物理机械性能的因素。结果表明，当分散剂／包覆剂(质量比)为4／6或10／4时，粒径不大于0．90mm的粉末丁腈橡胶粒子的质量分数为100．0％，相应硫化胶的物理机械性能达到块状丁腈橡胶硫化胶的。高耐磨炉黑填充粉末丁腈橡胶硫化胶的物理机械性能极大地依赖于高耐磨炉黑粒子在基体橡胶中的分散程度及其与基体黏结的紧密性。     

共凝聚法PSBR改性PVC的研究

试验研究包覆剂和超细碳酸钙对粉末丁苯橡胶（PSBR）粒径分布和PSBR／PVC共混物性能的影响。结果表明，以自制的Coron树脂[苯乙烯-马来酸酐（MA）共聚物，简称SMA]作包覆剂时，PSBR的粒径较小，PSBR／PVC共混物的拉伸强度和缺口冲击强度较大；当超细碳酸钙／丁苯胶乳质量比为3．5／6．5时，包覆剂SMA的适宜用量为0．8份，MA／苯乙烯的适宜质量比为0．56／0．24；当包覆剂SMA用量为0．5份时，加分散剂CH1-A的超细碳酸钙填充的PSBR粒径较小，对PVC的改性效果较好，超细碳酸钙的适宜用量为3．5～4份。     

超细碳酸钙超充粉末丁苯橡胶的制备

将高分子电解质包覆剂和超细碳酸钙加入丁苯胶乳中，通过共凝聚法制得粉末丁苯橡胶（PSBR）。实验结果表明，PSBR粒径不大于0．9mm,具有良好的力学性能。PSBR的粒径主要由包覆剂的用量决定，超细碳酸钙对橡胶粒子有隔离作用。     

活性剂FT对NR和BR及SBR胶料性能的影响

研究了橡胶活性剂ＦＴ与氧化锌不同并用比对ＮＲ,ＢＲ和ＳＢＲ胶料硫化特性和硫化胶物理性能的影响。试验结果表明,在ＮＲ和ＢＲ及ＳＢＲ胶料配方中活性剂ＦＴ可以等量替代４０％～６０％的氧化锌（即活性剂ＦＴ／氧化锌的最佳并用比为２．０／３．０～３．０／２．０）,而胶料的硫化特性基本保持不变,硫化胶物理性能稍有改善。     

白炭黑和炭黑在轮胎胎面胶配方中的比较

首先，我们通过比较ＳＢＲ炭黑和ＳＢＲ白炭黑硫化胶的各种物理性能，研究了ＳＢＲ炭黑硫化胶的滚动阻力［ｔｇδ（５０℃，１５Ｈｚ）］和耐湿滑性［ｔｇδ（０℃，１５Ｈｚ）］的实验室指标是否也适用于ＳＢＲ白炭黑硫化胶。ＳＢＲ白炭黑硫化胶的移动因子（ｌｏｇａＴ）、ｔｇδ值（０℃，１５Ｈｚ）以及摩擦系数μ值对温度的依赖关系几乎与ＳＢＲ炭黑硫化胶的相同。因此，我们决定将这些指标用作ＳＢＲ白炭黑硫化胶性能实验室试验的量度。接着，我们研究了ＳＢＲ的微观结构及其改性方法对ＳＢＲ白炭黑硫化胶的这些指标和蓝朋（Ｌａｍｂｏｕｒｎ）磨耗性能的影响。苯乙烯含量及玻璃化温度（Ｔｇ）对ｔｇδ（５０℃，１５Ｈｚ）和蓝朋磨耗性能有影响。分批聚合溶液丁苯橡胶（Ｓ－ＳＢＲ）的ｔｇδ（５０℃，１５Ｈｚ）比乳液丁苯橡胶（Ｅ－ＳＢＲ）和连续聚合Ｓ－ＳＢＲ低。Ｔｇ对０℃，１５Ｈｚ时的ｔｇδ具有显著影响。在ＳＢＲ白炭黑硫化胶中未观察到改性方法对物理性能的影响。这是ＳＢＲ白炭黑硫化胶和ＳＢＲ炭黑硫化胶的主要差别。通过Ｓ（动态应变振幅），Ｇ′（动态贮存模量）和ｔｇδ（１５０℃）可以解释ＳＢＲ白炭黑硫化胶的滚动阻力为何较低。     

超细碳酸钙填充粉末丁苯橡胶的制备

将高分子电解质包覆剂和超细碳酸钙加入丁苯胶乳中，通过共凝聚法制得粉末丁苯橡胶（PSBR）。实验结果表明，PSBR 粒径不大于0.9mm，具有良好的力学性能。PSBR的粒径主要由包覆剂的用量决定，超细碳酸钙对橡胶粒子有隔离作用。     

非硫黄调节型粉末CR的制备与性能

采用凝聚包覆法制备非硫黄调节型粉末CR，研究包覆剂的玻璃化温度(L)和用量对粉末CR性能的影响，并对粉末CR的粒子形貌进行了分析。结果表明，采用L为55．3或84．2℃的包覆剂制备的粉末CR的平均粒径较小，且粒径分布较窄；随包覆剂用量的增大，粉末CR的平均粒径减小，硫化胶的物理性能提高SEM分析表明，粉末CR的宏观粒子由多颗细小的初级粒子聚集而成，宏观粒子中存在大小不一的空洞，这些空洞有利于粉末CR的快速干燥。     

高岭土填充型粉末丁苯橡胶的制备与性能的研究

以SBR胶乳为原料，经表面改性的高岭土（MO）为填料，高分子树脂为包覆剂，以凝聚共沉法研制高岭土填充型粉末SBR[P(SBR/MO)]。研究了影响产物粒径及硫化胶力学性能的因素，并与块状SBR／MO1机械混炼胶料硫化胶的力学性能进行比较。结果表明：当高岭土用量≥100质量份、包覆剂用量≥5质量份时，可获得粒径≤0.9mm的P（SBR／MO1）达100％；当高岭土的用量为100质量份及其表面改性剂用量的4质量份、Tg为18℃的包覆剂的用量为5质量份时，所获得的P（SBR／MO1）硫化胶力学性能最好。     

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。