环保型可聚合乳化剂在丙烯酸酯乳液压敏胶中的应用

配合使用环保型可聚合阴/非离子乳化剂烯丙氧基脂肪醇聚氧乙烯醚硫酸铵(LR-10)和烯丙氧基脂肪醇聚氧乙烯醚(LG-20)作为乳化剂,通过种子预乳化半连续聚合工艺制备了丙烯酸酯乳液压敏胶(PSA)。探讨了乳化剂的配比、用量及种类对丙烯酸酯乳液性能的影响。结果表明,当m(LR-10)∶m(LG-20)=3∶1且复合乳化剂的质量分数为3%时(以混合单体总质量计),所制备的乳液综合性能最佳,此时,乳胶膜的稳定性、耐水性和粘接性最优,其吸水率为2.78%;GPC分析结果表明,随着复合乳化剂用量的增加,压敏胶溶胶部分的相对分子质量及其分布指数逐渐减小;FTIR结果表明,可聚合乳化剂参与了乳液聚合反应;与传统乳化剂体系相比,通过环保可聚合乳化剂LR-10/LG-20所制备的乳胶膜粘接性能最佳,其持粘力大于72 h。。     

葡萄糖基可聚合乳化剂的合成及其在乳液压敏胶中的应用

丙烯酸酯乳液压敏胶是一类应用广泛的低VOC含量环保胶黏剂。本文合成了一种葡萄糖基可聚合乳化剂-丁基葡萄糖苷马来酸酯（BGMAH）,并采用半连续种子乳液聚合工艺制备了BGMAH改性的丙烯酸酯乳液压敏胶。通过系统考察BGMAH的结构及用量等因素对乳液粒径、乳胶膜耐水性和粘接性能的影响发现,当复合乳化剂质量分数保持3%不变,m(BGMAH):m(OP-10):m(SDS)=2:1.5:0.5时,乳胶膜的粘接性能和耐水性能最佳。红外、热稳定性等分析表明丙烯酸酯乳液在改性过程当中发生了共聚交联反应,且改性后聚合物体系相容性良好,乳胶膜的玻璃化转变温度和热稳定性均提高,同时对聚合体系的反应机理也进行了研究。     

环保型可聚合乳化剂的合成及在压敏胶中的应用

合成了一种葡萄糖基可聚合乳化剂丁基葡萄糖苷马来酸酯(BGMAH),并与传统乳化剂十二烷基硫酸钠、烷基酚聚氧乙烯醚复配使用,采用半连续种子乳液聚合工艺制备了BGMAH改性的丙烯酸酯乳液压敏胶。考察了BGMAH的结构及用量对乳液粒径、乳胶膜耐水性和粘接性能的影响。结果表明:当BGMAH的质量占乳化剂总质量的50%时,乳胶膜的粘接性能和耐水性能最佳:初粘性14号球,持粘性36.4 h,180°剥离强度412.3 N/m,吸水率4.7%。FTIR结果表明:丙烯酸酯乳液在改性过程当中发生了共聚交联反应。DSC结果表明:BGMAH改性后聚合物体系相容性良好,乳胶膜的玻璃化转变温度(Tg)由改性前的-33.6℃提高到改性后的-28.7℃。     

聚丙烯酸酯乳液粒度及其压敏胶粘性能的研究

采用预乳化半连续聚合工艺,制备了乳液型聚丙烯酸酯类压敏胶。讨论了乳化剂用量、引发剂用量、预乳液滴加时间和搅拌速率对乳胶粒粒度以及压敏胶粘接性能的影响。实验表明:在不同影响因素下,乳胶粒的粒度与压敏胶粘接性能之间呈现出不同的变化关系。     

氢化丙烯酸松香/丙烯酸酯复合乳液的制备及其压敏胶的性能

以氢化丙烯酸松香为增黏树脂,将其溶解在丙烯酸酯单体中,预乳化后采用半连续乳液聚合工艺制备了氢化丙烯酸松香/丙烯酸酯复合乳液。研究了氢化丙烯酸松香的用量对单体转化率、凝胶率、溶胶相对分子质量及其分布、乳胶膜的玻璃化温度(Tg)和压敏胶粘接性能等的影响。结果表明,氢化丙烯酸松香对单体聚合具有一定的阻聚作用,随着氢化丙烯酸松香用量的增加,单体转化率、凝胶率及相对分子质量下降,相对分子质量分布变窄。氢化丙烯酸松香的合适用量为8.0%wt,此时压敏胶的初黏力为15#,180°剥离强度为10.6N.25mm-1,持黏力大于120h。     

不同可聚合乳化剂对丙烯酸酯乳液性能的影响

使用3种可聚合乳化剂制备了水基胶粘剂用丙烯酸酯乳液。考查了可聚合乳化剂与单体间的共聚性能,比较了各乳化剂用量对丙烯酸酯乳液的固含量和单体转化率、乳液稳定性(聚合稳定性、贮存稳定性、冻融稳定性)以及乳胶膜的耐水性等性能的影响。结果表明,乳化剂1-烯丙氧基-3-(4-壬基苯氧基)-2-丙醇聚氧乙烯(10)醚(ANPEO10)、烯丙氧基壬基酚聚氧乙烯(10)醚双磷酸(ANPEO10-P2)和烯丙氧基壬基酚聚氧乙烯(10)醚硫酸铵(DNS-86)均成功地聚合到丙烯酸酯聚合物中。用3种乳化剂制备的乳液性能各有特点。使用DNS-86以及ANPEO10-P2制得的乳液的贮存稳定性好;用ANPEO10制得乳液的冻融稳定性最好;使用DNS-86制得的乳胶膜的耐水性最好。3种乳化剂用量均为2.0%时,制得的乳液综合性能最好。     

纳米二氧化硅/聚丙烯酸酯复合乳液的合成及其涂膜性能

以改性硅溶胶与丙烯酸酯类单体原位聚合,采用单体预乳化、半连续滴加法制备了高硅含量纳米SiO2/聚丙烯酸酯复合乳液,研究了纳米SiO2和甲基丙烯酸(MAA)的用量、乳化剂配比和乳液固含量对乳液性能的影响,利用红外光谱、热重分析等方法对乳液结构和热稳定性进行了表征,测试了乳胶膜的性能。当SiO2用量为20%,乳化剂中m(OP-10):m(DNS-86)=1:3,功能性单体MAA用量为5%,乳液固含量为40%时,可制得稳定性良好的纳米SiO2/聚丙烯酸酯复合乳液,其涂膜硬度为6H,附着力1级,耐磨性达2500r,且具有良好的耐水性和耐热性。     

可聚合乳化剂对苯丙乳液胶粘剂性能的影响

采用可聚合乳化剂烯丙氧基壬基酚聚氧乙烯(10)醚硫酸铵(DNS-86),通过半连续法合成了苯丙乳液胶粘剂,探讨了可聚合乳化剂用量的变化对所制备的苯丙乳液胶粘剂性能的影响。结果表明:与常规乳化剂相比,用可聚合乳化剂合成苯丙乳液胶粘剂时,单体转化率提高;初粘力增加较大;随可聚合乳化剂用量增加,乳胶粒平均粒径减小,且皆呈单分散性。当可聚合乳化剂用量为单体总量的2．0％时,制得的苯丙乳液胶粘剂耐水性和粘接性最好,综合性能优异。     

耐水白聚合物乳液压敏胶的制备与性能研究

以丙烯酸异辛酯、丙烯酸丁酯和苯乙烯为主要聚合单体,采用半连续种子乳液聚合法制备了固含量约为50％的苯丙乳液压敏胶粘剂,考察了功能单体丙烯酸羟丙酯和丙烯酸、可聚合乳化剂以及乳液pH、乳胶膜厚度对乳液压敏胶的粘接性能、特别是耐水白性能的影响.研究结果表明:当湿膜厚度为30μm时,自制乳液压敏胶样的初粘力达到11号球,剥离强...     

马来酸酐化聚丁二烯改性丙烯酸酯乳液压敏胶的合成及表征

以马来酸酐化聚丁二烯(MLPB)作为交联改性助剂,通过半连续种子乳液聚合工艺制备了MLPB改性丙烯酸酯乳液压敏胶(PSA)。研究了聚合体系的反应机理、不同用量的MLPB对乳胶膜耐水性能、热稳定性能和粘接性能的影响,并对其结构进行表征。结果表明,当MLPB质量分数为5%时,乳胶膜的粘接性能和耐水性能最佳,此时吸水率为2.86%;红外光谱(FTIR)结果表明,丙烯酸酯乳液在改性过程当中发生了共聚交联反应;接触角测量仪(CA)显示,当MLPB的质量分数为5%时,乳胶膜的水接触角达到最大值,为108°;差示扫描量热分析法(DSC)结果论证,改性后聚合物体系相容性好,且乳胶膜的Tg随着MLPB质量分数的增加逐渐升高;热重分析(TGA)结果表明,MLPB改性后的乳胶膜具备较高的热稳定性。     

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。