纳米SiO2改性疏水缔合聚合物基的合成及性能评价

本文以丙烯酰胺(AM)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)和丙烯酸(AA)为亲水单体,十六烷基二甲基烯丙基氯化铵(CDMAAC)为疏水单体,在纳米SiO2的存在下,以EDTA/VA044/过硫酸铵/抗坏血酸为引发剂,通过自由基聚合法,合成了具有核壳结构的纳米SiO2改性疏水缔合聚合物.分别通过红外光谱和扫描电镜...     

疏水缔合两性聚丙烯酰胺的合成与性能研究

利用疏水单体苯乙烯能够提高分子链刚性,可以与丙烯酰胺进行共聚,并且苯乙烯与丙烯酰胺共聚物在水溶液中存在疏水缔合作用的特性,将苯乙烯、丙烯酰胺和3-[2-(N-甲基丙烯酰胺基)-乙基二甲基铵基]丙基磺酸盐采用反相乳液聚合的方式进行聚合反应得到一种疏水缔合的两性聚丙烯酰胺。聚合物结构经过核磁和红外验证,并对其耐盐性能进行验证,着重研究了其耐温性能,该种聚合物耐温性能有显著提高。该聚合物经100℃老化48h后剪切黏度保留率达到63%,而80℃老化48 h后剪切黏度保留率则高达87%。     

阳离子型聚合物稠化剂的合成与性能评价

以丙烯酰胺、30%丙烯酰胺/甲叉双丙烯酰胺(29∶1)、甲基丙烯酰氧乙基三甲基氯化铵、十六/十八烷基二甲基烯丙基氯化铵为主要合成单体,聚合引发剂为水溶性2,2-偶氮二(2-甲基丙基脒)二盐酸盐,合成疏水缔合型阳离子聚合物稠化剂(PASM)。对产物进行结构表征及性能测试,结果表明,稠化剂PASM的临界缔合浓度为0.5%,分子量为417.3×10⁴,耐Na⁺和Ca²⁺能力强,并且随着矿化度的增加,起初体系的粘度呈现出上升趋势,表现出优异的增稠性能。低浓度使用状态下即可达到较好的防膨效果,悬砂性能优异,经过硫酸铵破胶后无残渣,破胶液不会对地层造成二次伤害,具有广阔的工业化前景。     

新型疏水缔合水溶性聚合物的合成及溶液性能研究

以四甲基乙二胺分别与溴代正十四烷/溴代正十六烷反应得到单季铵盐,再与溴丙烯反应即得到2种新型疏水单体十四烷基烯丙基二溴化四甲基乙二铵(C14PDBTMN)和十六烷基烯丙基二溴化四甲基乙二铵(C16PDBTMN)。用1HNMR和IR对单体结构进行表征,结果表明为目标化合物。以C16PDBTMN为功能性单体,和丙烯酰胺进行共聚得到新型疏水缔合物P(C16PDBTMN/AM),研究表明,新型疏水缔合物具有其独特的抗盐、抗剪切性能。     

反相乳液聚合制备疏水缔合聚合物AAMS-2及其压裂液性能评价

采用反相乳液聚合方法制备了AM(丙烯酰胺)/AMPS(2-丙烯酰胺-2-甲基丙磺酸)/疏水单体M(二甲基十八烷基烯丙基氯化铵)/刚性单体S(4-丙烯酰基氨基苯磺酸钠)的四元疏水缔合聚合物AAMS-2,并用红外光谱对聚合物进行了表征。热重分析(TGA)表明聚合物在240℃下化学结构稳定。利用扫描电镜(SEM)清晰观察到AAMS-2的乳液颗粒和水溶液形成的网状结构。AAMS-2压裂液具有良好的粘弹特性、携砂、破胶和岩心低伤害特性。耐温耐剪切测试表明体系具有优良的耐温能力,0.6%的AAMS-2压裂液在150℃、170 s^(-1)条件下剪切2 h,表观粘度保持在50 mPa·s以上。     

超临界CO2下三元含氟疏水缔合聚合物的合成及溶液性能研究

设计聚合物的分子结构并在超临界CO2下以丙烯酰胺(AM)、2-甲基-2-丙烯酰胺基丙磺酸(AMPS)及甲基丙烯酸十二氟庚酯(G04)为单体合成三元含氟疏水缔合聚合物,并用FTIR和元素分析对结构进行表征。研究反应温度、压力及引发剂加入量对产物聚合反应转化率及相对分子量的影响,并对三元含氟疏水聚合物浓度对溶液表观粘度的影响进行研究。结果表明:在超临界CO2体系下可制备三元共聚含氟聚合物,且由于含氟疏水基团的存在,该聚合物水溶液具有明显的疏水缔合作用。     

耐盐型疏水缔合聚合物的制备及流变性能

采用丙烯酰胺(AM)、丙烯酸(AA)、2-丙烯酰胺-2-甲基丙烷磺酸(AMPS)和水溶性阴离子疏水单体S-18制备了新型耐盐疏水缔合聚合物S-18HPAM。聚合放热测试表明:疏水单体含量的增加导致放热时间的延长,更有利于疏水结构的形成。微观结构测试表明:聚合物具有复杂的网状结构,在NaCl溶液中网状结构更为明显。流变测试结果表明:聚合物在盐溶液中具有良好的耐温和抗剪切性能。聚合物质量分数为0.3%(基于溶液总质量),温度90℃,剪切速率170 s–1和NaCl质量浓度20000 mg/L条件下,剪切后表观黏度大于70 mPa·s。在总矿化度20000 mg/L模拟地下水条件下,S-18HPAM质量分数为0.3%,剪切后黏度为70 mPa·s,加入质量分数0.5%表面活性剂十二烷基硫酸钠(SDS)后,黏度增加到170m Pa·s。储能模量G'随着聚合物质量分数的增加而增大,体系弹性增强,同时疏水结构单元数量增加,形成致密的空间网络结构。     

疏水缔合聚丙烯酰胺的合成及性能评价

以丙烯酰胺(AM)、丙烯酸(AA)、甲基丙烯酰氧乙基二甲基十六烷基溴化铵(C16DM)为单体合成了疏水缔合聚丙烯酰胺(HAPAM)。最佳的反应条件为:w(引发剂)=0.3%(以单体总质量计),x(C16DM)=0.5%,x(AA)=25%,w(总单体)=20%,pH=7～8,反应温度50℃,反应时间8 h。采用元素分析和红外光谱对其结构进行表征,同时研究表明,质量浓度1 g/L时溶液表面张力可降至42.2 mN/m,接近3 g/L时出现临界缔合浓度;黏度随温度上升缓慢下降,溶液具有剪切稀释性。     

反相乳液聚合制备疏水缔合聚合物AAMS-2及其压裂液性能评价

采用反相乳液聚合方法制备了AM(丙烯酰胺)/AMPS(2-丙烯酰胺-2-甲基丙磺酸)/疏水单体M(二甲基十八烷基烯丙基氯化铵)/刚性单体S(4-丙烯酰基氨基苯磺酸钠)的四元疏水缔合聚合物AAMS-2,并用红外光谱对聚合物进行了表征。热重分析(TGA)表明聚合物在240℃下化学结构稳定。利用扫描电镜(SEM)清晰观察到AAMS-2的乳液颗粒和水溶液形成的网状结构。AAMS-2压裂液具有良好的粘弹特性、携砂、破胶和岩心低伤害特性。耐温耐剪切测试表明体系具有优良的耐温能力,0.6%的AAMS-2压裂液在150℃、170 s~(-1)条件下剪切2 h,表观粘度保持在50 mPa·s以上。     

耐温疏水缔合聚合高分子制备及流变性能研究

以丙烯酰胺（AM）?2-丙烯酰胺-2-甲基丙磺酸（AMPS）为原料,引入长链疏水单体DAB和刚性疏水单体Ars,采用自由基水溶液聚合得到耐温型疏水缔合聚合高分子PAS,使用红外光谱仪和扫描电镜表征PAS分子结构并观察分子链的聚集状态,使用热重仪测试聚合高分子的耐热性,RS6000流变仪测试PAS的流变性能并与常规疏水缔合聚合物对比。结果表明：PAS干粉372℃失重50%,具有良好耐热性;聚合高分子PAS具有复杂空间网络结构并观察到疏水侧链的缔合微区,经流变仪频率扫描与应力扫描,聚合高分子PAS表现出良好的触变性和黏弹性,聚合高分子PAS在170 s-1条件下耐温达150℃可保持121 mPa·s,在100℃条件下剪切1.5h,黏度为198mPa·s,经过不同速率剪切后黏度恢复率为78.5%,与常规的疏水缔合型聚合物相比具有更好的耐温性和抗剪切性能。     

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。