湿法碳酸钙生产工艺及其在粉末涂料中的应用研究

介绍了重质碳酸钙的干法、湿法生产工艺,并将其与轻质碳酸钙进行了对比;研究了湿法超细重钙和轻质纳米碳酸钙在粉末涂料中的应用情况。结果表明:湿法研磨重度碳酸钙应用于粉末涂料中,其涂膜光泽,耐冲击等性能优于轻质碳酸钙。     

超细重质碳酸钙在PVC电缆护套料上的应用

探讨了重质碳酸钙、轻质碳酸钙和活性碳酸钙的工艺性能特点、选择了试验配方、用超细重质碳酸钙取代了轻质碳酸钙、生产并检测了粒料性能。结果表明：采用超细重质碳酸钙后,其它组分和用量不变时,其环保性、加工流动性、物理力学性能都满足指标要求。     

超细重质碳酸钙表面改性及在硅橡胶中的应用研究

选用硬脂酸钠、硅烷偶联剂及钛酸酯偶联剂对超细重质碳酸钙通过湿法进行接枝改性,采用傅里叶变换红外光谱、热失重分析仪和粒径分析对超细重质碳酸钙进行了表征。研究了3种改性超细重质碳酸钙对室温硫化硅橡胶流变性能及力学性能的影响。结果表明,改性后的超细重质碳酸钙能够很好地在硅橡胶中进行分散,经硅烷偶联剂改性的超细重质碳酸钙填充的硅橡胶呈现出了较佳的力学性能。     

超细重质碳酸钙填充聚氨酯合成革的研究

通过力学测试和SEM，考察了超细重质碳酸钙(下简称超细重钙)填充的湿法聚氨酯合成革的力学性能和微观结构，结果表明：超细钙能够均匀地分散于聚氨酯树脂中，填充性能优于轻质碳酸钙填充的革，和木质素相当，超细重钙是聚氨酯合成革(下简称PU革)良好的填充剂。     

改性聚丁二烯在超细重质碳酸钙表面活化中的应用

研究了改性聚丁二烯在超细重质碳酸钙表面活化中的应用效果。试验结果表明,经改性聚丁二烯改性的超细重质碳酸钙填充SBR胶料的硫化速度明显加快,硫化胶的拉伸强度、定伸应力和撕裂强度提高1倍以上,耐屈挠龟裂性能提高3～5倍,在改性聚异戊二烯、改性聚丁二烯、钛铝偶联剂,钛酸酯TM-S和TM-38S中以改性聚丁二烯对超细重质碳酸钙的改性效果最好。当改性聚丁二烯的质量分数为0.02～0.03时,改性超细重质碳酸钙填充SBR胶料的各项性能最佳。     

碳酸钙产品分类与命名建议

碳酸钙产品广泛应用于塑料、造纸、涂料、橡胶、日化、医药、食品、饲料等行业.根据加工方法不同可分为重质碳酸钙(GCC)、轻质碳酸钙(PCC);根据是否改性可分为普通碳酸钙和活性碳酸钙;根据用途不同可分为专用碳酸钙.为了方便行业管理,便于统计,有利于用户选用,建议按产品加工方法及其平均粒径大小分为轻质和重质两大类.轻质碳酸钙分为轻质碳酸钙(＞2.0μm)、超细碳酸钙(0.1～2.0μm)、纳米级碳酸钙(≤0.1μm )等3个级别,每个级别中分为活性与普通产品、各种专用产品等;重质碳酸钙分为重质碳酸钙(＞10μm)、微细重质碳酸钙(2.0～10μm)、超细重质碳酸钙(0.1～2.0μm)等3个级别,每个级别中分为活性与普通产品、各种专用产品等.各类各种碳酸钙产品物理及化学指标分别符合国家、行业或企业标准要求.     

碳酸钙产品及其展望

介绍几种碳酸钙产品:轻质碳酸钙、重质碳酸钙、活性碳酸钙、纳米碳酸钙,并且从理化性质、制备方法、颗粒形状以及应用等方面对重质碳酸钙与轻质碳酸钙进行了比较,并对轻质碳酸钙、重质碳酸钙、纳米碳酸钙三者的生产工艺以及发展前景作了简单介绍。     

水中悬浮法表征碳酸钙的活化效果

研究了水中悬浮法对碳酸钙活化效果的表征。结果表明，该方法适于表征活性轻质碳酸钙和颗粒极细的活性重质碳酸钙。     

碳酸钙在我国橡胶工业中的应用和发展

介绍了我国碳酸钙品种，性能及在橡胶工业中的应用和发展。碳酸钙分为重质碳酸钙，轻质碳酸钙和活性碳酸钙[主要指超细活性碳酸钙（又称纳米碳酸钙）]，广泛应用于轮胎，胶管，胶带，胶鞋，电线电缆，密封制品，胶数量级和胶布等橡胶制品中，采用先进的表面改性方法和开发多品种，针对性强，性能优异的改性剂，以使纳米碳酸钙真正发挥纳米级粒子的作用，以及扩大超细活性碳酸钙在轮胎和艳色橡胶制品中的应用是扩大碳酸钙在橡胶工业中应用的有效途径。     

国内外简讯

日本白石钙工业株式会社和备兆粉化株式会和共同开发1um的重质碳酸钙,并开始生产。重质碳酸钙用天然石灰石粉碎制得2um级以下产品困难。以上两个公司共同开发湿法粉碎制得微粒子膏状物,干燥得1um重质碳酸钙。能够代替合成轻质碳酸钙,价格降低50％。碳酸钙有机械粉碎的重质碳酸钙和化学合成后轻质碳酸钙二种。1um以下后轻质碳酸钙用于塑料、涂料,造纸作填料。重质碳     

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。