交联型单分散聚苯乙烯微球的制备

以聚乙烯吡咯烷酮（PVP）为分散剂，偶氮二异丁腈（AIBN）为引发剂，乙醇为分散介质，二乙烯基苯（DVB）为交联剂进行了苯乙烯（St）的分散聚合；讨论了引发剂、交联剂、分散剂、单体用量对聚合物粒径及分布的影响，制备了交联型单分散聚苯乙烯微球。实验表明：当交联剂质量分数达到单体质量分数的1％时，微球依然可以保持良好的单分散性。在聚合体系中引入抗坏血酸，使其与微量的氧结合，有效地提高了微球的均匀度。     

种子溶胀法制备单分散交联聚苯乙烯微球

采用分散聚合法制备了聚苯乙烯(PS),并以此作为种子,与溶胀剂和单体、交联剂的混合物经二步溶胀聚合法,制备了单分散交联PS微球.讨论了溶胀剂用量、交联剂用量和单体用量对溶胀微球粒径和粒度分布的影响,以及交联剂用量对溶胀微球形貌的影响.结果表明,当溶胀剂的用量为3 g,交联剂为1 g,单体用量为7 g时可制得平均粒径为6.84 μm且单分散性较好的交联PS微球.     

溶液/乳液二次聚合制备单分散微米级交联聚苯乙烯微球的研究

尝试一种不同于以往传统方法合成单分散微米级 (6-1 0μ)交联聚苯乙烯微球—溶液 /乳液二次聚合法。研究了引发剂、溶剂、交联剂、稳定剂、乳化剂含量对聚合物微球粒径的影响 ,得出最佳的反应条件。研究发现粒径随引发剂和交联剂浓度的增加而增大。随介质水用量的增加而增大 ,随乙醇用量增加而减小 ,随稳定剂和乳化剂浓度的增加而减小。     

交联聚苯乙烯的合成及力学性能研究

以苯乙烯为单体,二乙烯基苯为交联剂,采用自由基交联共聚合的方法合成出交联聚苯乙烯热固性塑料,并运用红外光谱、差示扫描量热分析对其进行了表征。研究了交联剂用量及后期热处理对其力学性能的影响。结果表明,交联聚苯乙烯的力学性能随着二乙烯基苯用量的增加呈先增后减变化,其含量在1.6～1.8 质量%时交联聚苯乙烯具备最佳综合力学性能,适当的后期热处理使得交联聚苯乙烯的拉伸强度及断裂伸长率分别提高12 %和20 %。     

溶剂在交联硅橡胶中无限稀释扩散系数测定

气相色谱法测定溶剂与聚合物材料之间的相互关系是一个快速、准确、方便的方法，为此利用气相色谱法测定了小分子溶剂在不同交联剂含量的交联硅橡胶中的无限稀释扩散系数，并研究了交联剂用量对无限稀释扩散系数的影响，这为研究交联硅橡胶特性提供了新方法。     

聚氨酯／聚苯乙烯共交联树脂研究

采用同步交联的方法，制备了一系列的蓖麻油聚氨酯／聚苯乙烯（COPU／PS）交联聚合物，并且研究了它们的力学性能和溶胀性能。结果表明，当PS／COPU、BPO／Sf（苯乙烯）质量比分别为30％和1．5％时，OH TMP／OHco、NCO／OH摩尔比分别为0．2和1．3时，材料的相容性好，协同效应明显，此时力学性能最佳。溶胀实验表明，当COPU／PS材料中PS质量分数为20％以上或PU质量分数为60％以上时，由于两相互穿作用使共交联材料分别对二甲苯和二甲基甲酰胺的溶胀趋缓：并且随着交联剂三羟甲基丙烷（TMP）的增加，平衡溶胀度增幅变小，到TMP羟基和蓖麻油羟基摩尔比值大于0．2后，平衡溶胀度变化不大。     

低温复合交联凝胶体系的制备与评价

针对春风油田低温、高矿化度的储层条件,以部分水解聚丙烯酰胺(HPAM)为主剂、J1和J2为交联剂制备了聚合物凝胶体系调剖体系。凝胶配方包括:1.0%HPAM、0.1%～0.5%无机交联剂J1、0.5%～2.5%有机交联剂J2、0.2%除氧剂D3。研究了聚合物浓度、交联剂浓度和矿化度对体系成胶时间及强度的影响。结果表明,该复合凝胶可在30℃下成胶,通过调节交联剂的用量可使成胶时间控制在10～72 h。当单独使用0.5%J1交联剂时,凝胶的黏度为9 756 mPa·s,当交联剂用量为0.5%J1、2.5%J2时凝胶黏度达到了28 576 mPa·s,复合交联的方法使凝胶性能得到大幅度提高。室内实验封堵率达到95.88%,表明该凝胶体系具有良好的封堵性能。     

笼型聚倍半硅氧烷交联聚苯乙烯微球疏水性的研究

采用分散聚合法制备聚苯乙烯微球,以甲基丙烯酸为交联剂、过硫酸铵为引发剂,将聚倍半硅氧烷与聚苯乙烯微球进行交联,并对交联后的聚苯乙烯微球进行红外光谱表征和热重分析。探讨了聚合温度对聚苯乙烯微球粒径的影响,着重分析了影响微球疏水性能的聚乙烯和十二烷基硫酸钠的因素。研究结果表明:聚乙烯对交联微球的浸润接触角以及十二烷基硫酸钠对交联微球的吸湿率影响显著;当w(聚乙烯)=40%(相对聚苯乙烯总质量而言)时,接触角为最大值146°,疏水性能较佳;当w(十二烷基硫酸钠)=1.5%(相对于乳液总质量而言)时,吸湿率较低为7.3%。     

高热稳定性和可逆交联性质的含新型偶氮发色团电光聚合物的研究

制备了两种新型的分别含有以三苯胺为电子给体的偶氮类发色团作为特征活性官能团和3-呋喃甲酸及受保护的马来酰亚胺的可交联型聚合物体系．通过研究表明利用该制备方法，发色团在聚合物中的含量得到了极大的提高，分别达到32．1％（NLO1_P1）和44．4％（NLO1_P2）．该聚合物体系以“DielsAlder”[4＋2]环加成反应作为其交联特征，具有高温非交联、低温交联的特点，其过程与以往的热交联型聚合物相反，可解决传统电光交联聚合物中存在的热交联对极化效率影响的问题并用热失重分析法（TGA）和差示扫描量热法（DSC）分析了这一过程．此外DA交联型聚合物，不需要引入额外的助交联剂，克服了传统热交联聚合物分离难的问题，最大程度的保证了材料的纯度．     

交联型P（AN-MA）凝胶聚合物电解质的制备与性能研究

采用丙烯腈（AN）和丙烯酸甲酯（MA）溶液聚合的方法合成了轻度交联的P（AN-MA）共聚物自支撑膜，可用做锂离子电池聚合物电解质膜基体。通过FTIR、IXSC、SEM等测试方法对交联共聚物的结构进行了表征，利用交流阻抗等电化学方法对电解质膜的导电性能进行了研究。结果表明：当交联剂用量为1．5％时，轻度交联的P（AN-MA）共聚物膜形成立体网状结构且富含大量纳米、超微米孔洞，有利于大量锂离子的嵌入；室温下该聚合物膜的电导率可达3．50×10^-4S／cm，达到聚合物锂离子电池电解质的电导率要求。     

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。