氯化聚丙烯接枝马来酸酐的研究

为了进一步提高氯化聚丙烯接枝马来酸酐的接枝率,优化工艺条件和不同组分的用量,采用正交实验法,研究了马来酸酐(MAH)用量、引发剂过氧化苯甲酰(BPO)用量、反应温度和反应时间对氯化聚丙烯接枝马来酸酐接枝率的影响。结果表明,引发剂BPO用量对接枝率的影响最为明显,而反应时间相对最弱。4种因素的极差递减顺序为:引发剂BPO用量、MAH用量、反应温度和反应时间。     

聚乙烯蜡溶液接枝马来酸酐工艺优化的研究

以BPO为引发剂、聚乙烯蜡（PEW）和马来酸酐（MAH）为反应物，采用溶液法合成聚乙烯蜡接枝马来酸酐（PEW-g-MAH），使用L。（3。）正交实验表考察不同反应温度、时间、MAH和BPO用量对PEW-g-MAH接枝率的影响。红外分析表明MAH已经接枝到PEW分子链上；在PEW用量为10g、MAH为1．40g、BPO为0-10g、温度100℃、反应时间60min条件下，可得到接枝率为2．95％的PEW—g—MAH。     

工艺和配方对熔融法制备丁苯橡胶接枝马来酸酐的影响

采用熔融接枝法制备了丁苯橡胶接枝马来酸酐（SBRgMAH）,讨论了马来酸酐（MAH）和第三组分的用量、转子转速、反应时间以及引发剂的种类及用量对SBRgMAH接枝率和接枝效率的影响。用化学滴定法测试SBR-g-MAH的接枝率和接枝效率。结果表明,在引发剂BPO用量为0．25份、MAH用量为5．0份、第三组份用量为6．0份,反应温度135℃,转子转速40r／min,反应时间3min的条件下SBR-g-MAH的接枝率最大,达到3．21％。     

MAH溶液法接枝SBS的研究

采用马来酸酐（MAH）作为接枝单体,对苯乙烯—丁二烯—苯乙烯三嵌段共聚物（SBS）进行溶液接枝。研究了反应温度、反应时间、马来酸酐用量、引发剂种类及用量对接枝率的影响。得到最佳反应条件为：m（SBS）/m（MAH）/m（BPO）/m（溶剂）=100：10：0.8：400,反应温度75℃。反应时间3 h;红外光谱图证实了接枝物的生成。     

聚丙烯（PP）／黏土复合材料熔融剂的研究

以马来酸酐（MAH）等为单体接枝聚丙烯作为聚丙烯（PP）／黏土复合材料熔融剂,考察了马来酸酐用量、引发剂过氧化苯甲酰（BPO）用量、反应时间、温度等因素对产物接枝率的影响,并通过红外光谱图对PP-g-MAH进行表征。结果表明,当m（PP）：m（复配单体）：m（BPO）=10．0：2．0：0．6、反应温度控制在120℃左右、复配单体为马来酸酐／苯乙烯时,熔融剂PP-g-MAH的接枝率可获得较大值3．9％。实验同时表明,反应时间对接枝率的影响不大;苯乙烯的加入对接枝率有较大的影响,与普通单体单一马来酸酐相比,加入苯乙烯的接枝率明显提高。     

马来酸酐接枝乙烯-丙烯酸丁酯共聚物的研究

以过氧化物为引发剂、马来酸酐（MAH）为单体,采用溶液法对乙烯-丙烯酸丁酯共聚物（EBA）进行接枝改性,并用傅立叶红外光谱技术对接枝物（EBA—g—MAH）进行了表征。系统考察了引发剂种类及用量、反应温度、反应时间、单体用量等因素对接枝率及熔体流动速率的影响。实验结果显示,EBA接枝MAH的优化反应条件是：原料配比为m（EBA）：m（MAH）：m（BPO）=100：2：0．28,反应时间为4h,反应温度为90℃,接枝率可达0．78％。随着反应温度的升高,接枝物的熔体流动速率急剧下降。不同的过氧化物引发剂对接枝反应的影响明显不同,与过氧化二异丙苯（DCP）相比,选择过氧化二苯甲酰（BPO）为引发剂,接枝效果较好,同时所得接枝物的MFR值适中。     

ABS树脂熔融接枝马来酸酐的研究

研究了在双螺杆挤出机中使用自制的引发剂进行马来酸酐（MAH）熔融接枝（丙烯腈／丁二烯／苯乙烯）共聚物（ABS）的反应，对反应机理进行了讨论，红外光谱分析证明，MAH成功地被接枝到ABS的主链上，对ABS的组分分离证明接枝发生在ABS的丁二烯部分。研究了MAH用量，引发剂含量，反应温度和螺杆转速及溶剂对接枝反应的影响，发现接枝率随着MAH用量的增加，反应时间和螺杆转速的增加而增大；当增大引发剂含量时，接枝率呈现先增加后降低的趋势，自制引发剂比常用的过氧化二异丙苯（DCP）或过氧化苯甲酰（BPO）引发剂接枝效果要好得多，而且受加工条件的影响小。     

功能化聚乙烯蜡的制备与表征

用溶液接枝法制备了马来酸酐（MAH）和马来酸酐／苯乙烯（St）双单体接枝的功能化聚乙烯蜡（PEW），考察了反应时间、温度、引发剂、单体用量对产物接枝率的影响。结果表明，接枝改性的最佳条件为温度110－120℃，反应时间2h，原料质量比为m(PEW)/m(MAH)/m(BPO)r=100/4/2/0.3。用傅立叶红外光谱和差示扫描量热分析表征了接枝产物的结构。     

低相对分子质量反式聚丁二烯接枝马来酸酐的研究

研究了在二甲苯溶剂中，以过氧化二苯甲酰(BPO)为引发剂，低相对分子质量反式．1，4-聚丁二烯(LMTPB)接枝马来酸酐的反应。考察了引发剂用量、反应时间、马来酸酐用量、抗凝胶剂用量、溶剂用量对接枝反应的影响。结果表明：聚合物的接枝率随引发剂用量的增大、反应时间的延长、马来酸酐用量的增大和溶剂用量的减小而增大。聚合产物的凝胶含量随引发剂用量的增加、反应时间的延长、溶剂用量的减小逐渐增大，而随马来酸酐用量的增大变化不大。加入适量的抗凝胶剂，不仅可减少凝胶含量，还可提高接枝率。IR分析表明，马来酸酐确已接枝在LMTPB上。而DSC测试结果表明，接枝聚合物的结晶度和熔点均下降。     

聚丙烯熔融挤出接枝马来酸酐的研究

研究了通过双螺杆挤出机聚丙烯熔融挤出接枝马来酸酐制马来酸酐接枝聚丙烯（PP—g—MAH）的工艺，包括单体马来酸酐（MAH）、引发剂DCP的用量及熔融反应温度和时间对聚丙烯（PP）熔融接枝MAH的接枝率的影响。结果表明：DCP、MAH的用量对PP—g—MAH接枝率影响比较明显，其最佳配比为DCP0．15份、MAH2份；最佳工艺条件为挤出螺杆转速40r／min，反应温度195-200℃。     

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.     

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。     

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.