自交联型含氟丙烯酸酯改性聚氨酯乳液制备及性能研究

本文以含氟丙烯酸酯对聚氨酯进行了改性,并将双丙酮丙烯酰胺引入改性的聚氨酯链段,合成了自交联型氟化丙烯酸酯改性聚氨酯乳液(FPUA),利用红外光谱(FT-IR)分析、粒径分布分析、接触角测试对FPUA胶膜的结构与性能进行了表征。探讨了氟单体含量对胶膜的性能的影响。实验结果表明,乳液的粒径随着PUA预聚体用量的增加而增大,接触角随着含氟单体的增加而增大,吸水率随着含氟单体的增加而减小。考虑到成本问题,当氟单体含量为10%时,胶膜的综合性能最好,水接触角可达到108°,吸水率仅为10.19%。     

含氟丙烯酸酯核壳乳液的制备与性能研究

以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)为主单体,分别加入丙烯酸六氟丁酯(HFBMA)和甲基丙烯酸十二氟庚酯(DFHM)作为聚丙烯酸酯改性剂,制备了2种含氟丙烯酸酯核壳乳液。采用1H-NMR、TEM、DSC、EDS-SEM、Zeta电位及纳米激光粒度仪等表征了乳胶粒子的组成、结构、粒径及其分布以及乳胶膜表面氟元素的含量。研究了2种含氟单体的用量对乳液稳定性、乳胶膜吸水率、单体转化率、乳胶膜表面疏水疏油性等的影响;研究结果表明:DFHM的改性效果明显好于HFBMA。当DFHM的加入量为4%时,乳胶膜对水的接触角达到93.5°,吸水率降为11.54%,对正己烷的接触角达到82.0°;乳胶粒子的平均粒径70.02 nm,粒径分布窄(PDI=0.082),且具有核壳结构;SEM-EDS测试结果显示,制备的含氟聚合物在成膜过程中,氟元素更易向表面迁移,从理论的5.70%上升到13.47%,从而使乳胶膜具有更好的疏水和疏油性能。     

乳液聚合交联改性提高疏水性氟代丙烯酸酯的力学性能

为了改善丙烯酸酯的力学性能,以丙烯酸酯为主要单体,甲基丙烯酸十二氟庚酯为功能单体,1,4-丁二醇二丙烯酸酯(BDDA)为交联剂,采用核壳乳液聚合法合成了水性含氟丙烯酸酯。考察了反应条件,并对乳液的稳定性、粒径,以及乳液膜的拉伸强度、断裂伸长率、硬度、水接触角和化学结构进行了表征。结果表明,BDDA的加入可以有效提高乳液膜的拉伸强度、断裂伸长率及硬度。当BDDA占单体质量3%时,乳液的平均粒径为63.8 nm,转化率为99.2%,乳液膜的综合性能最好,分别为:吸水率4.9%,水接触角98.8°,拉伸强度1.94 MPa,断裂伸长率743.6%,硬度45.6 HA。其拉伸强度和断裂伸长率分别是未改性含氟丙烯酸酯乳液膜的1.73倍和1.46倍。     

含氟丙烯酸酯共聚物无皂乳液的粒子形态与性能研究

研究了通过半连续滴加法制备的无皂含氟丙烯酸酯聚合物乳液乳胶粒形态、聚合条件对乳胶粒粒径的影响,测定了乳液性能和乳胶膜的表面性能。制备的含氟乳液的乳胶粒呈圆形,粒径分布窄。乳液稳定性好,含氟乳胶膜对水的接触角为110.2°,吸水率低,表现出优异的表面性能。     

核壳型含氟丙烯酸酯乳液的合成及表征

以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、甲基丙烯酸六氟丁酯(HFMA)等为主要原料,采用多步乳液聚合法,合成了具有核壳结构的含氟丙烯酸酯乳液。实验结果表明,主要单体质量比m(MMA)∶m(BA)=45∶55,核壳单体质量比为6∶4,含氟单体质量分数为7%,乳化剂质量分数为3%~4%时,制备得到的含氟丙烯酸乳胶粒子具有软核/硬壳结构,粒径为120 nm,乳胶膜吸水率为7%。通过傅里叶红外光谱法(FTIR)对乳液结构进行表征,结果表明,含氟单体参与了有效聚合;差示量热扫描(DSC)和热重分析法(TG)分析结果表明,聚合物存在两个玻璃化温度(-10.2℃和58.4℃),且热分解温度比不含氟的聚合物提高了59℃;接触角测试结果表明,当w(HFMA)≥7%时,乳胶膜正面与水的接触角为98.2,°说明所合成的核壳结构含氟丙烯酸酯乳液中有机氟富集于壳层,涂膜的耐热、疏水性良好。     

细乳液聚合制备纳米SiO2／含氟丙烯酸酯复合乳液及其性能研究

采用溶胶-凝胶法,以正硅酸乙酯为前驱物,在丙烯酸酯单体为油相介质中原位生成纳米SiO2粒子,并通过细乳液聚合,制备出纳米Si02／含氟丙烯酸酯复合乳液。研究了含氟单体和SiO2的用量对复合乳胶膜性能的影响,并采用FT-IR,DSL等分析手段对产物进行了表征。结果表明：该乳液具有良好的稳定性,粒径分布较窄。当（甲基丙烯酸十二氟庚酯）FA与SiO2的用量分别为6％和5．5％时,乳胶膜表现出良好的疏水性能,对水的接触角达到了102．7°,吸水性降低到6．9％。     

核壳型短链含氟丙烯酸酯乳液的合成及表征

该文研究了核壳型短链含氟丙烯酸酯乳液的合成与表征。以甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA)的共聚体为核,短氟碳链2-(全氟己基)乙基甲基丙烯酸酯(FMA6)和非氟烷基丙烯酸酯的共聚体为壳,采用多步乳液聚合法,合成系列具有核壳结构的含氟丙烯酸酯乳液,研究了壳相中氟单体用量和非氟烷基丙烯酸酯的烷基链长度n(链长n=4、8、12、16、18)对产物疏水疏油性能的影响,并对产物进行表征。结果表明:当采用氟单体用量为总单体质量的8.5%,甲基丙烯酸十六酯(CMA)的共聚体为壳层时,由合成乳液制得的乳胶膜的疏水疏油性最佳,对水接触角为124.67°,对二碘甲烷接触角为112.76°。FTIR、TEM和DSC/TGA表征表明,原料单体均参加了反应;乳液颗粒具有明显的核壳结构;聚合物存在两个玻璃化温度(-18.87℃和32.08℃),热分解温度比不含氟的聚合物提高了近20℃。由此说明,用合成的核壳型短链含氟丙烯酸酯乳液制得的涂膜具有优异的疏水疏油性和耐热性能。     

耐污涂料用氟改性纯丙交联乳液的制备及其性能

引入含氟和交联单体,制备耐污涂料用氟改性丙烯酸酯交联乳液,考察氟单体、交联单体种类及含量对乳胶膜和漆膜接触角和耐污性能的影响。FTIR分析表明甲基丙烯酸全氟庚酯（DFMA）单体成功接枝到聚合物主链上。粒径分析表明制得的氟改性纯丙乳液粒径为90nm时,涂膜耐污性能最优。当引入6.0%DFMA,乳胶膜和漆膜与水、油的接触角都显著增大。当引入交联体系为双丙酮丙烯酰胺和已二酰肼（DAAM/ADH）,且用量为4.0%时,涂膜的综合耐污性达到11.9%。     

含氟丙烯酸酯乳液合成及其内墙涂料防涂鸦性的研究

以烯丙氧基羟丙基磺酸钠(COPS-1)、壬基酚聚氧乙烯醚硫酸铵(CO-436)和NP-10为复合乳化剂,过硫酸铵为引发剂进行了含氟丙烯酸酯乳液聚合研究,测定不同含氟单体含量制备的乳液干膜及漆膜与水、油的接触角,比较含氟单体含量、不同交联单体及含量对涂膜耐污性能的影响。研究结果表明:随含氟单体含量增加,乳液干膜及涂膜与水、油接触角增大;由12%甲基丙烯酸十二氟庚酯、5%双丙酮丙烯酰胺所合成的含氟丙烯酸酯乳液,稳定性高,耐沾污性好;当乳液含量为涂料配方总量的36%时,涂膜对水彩污迹的耐污性能明显改善,且遮盖力好。     

半连续细乳液聚合制备含氟乳胶粒子及性能研究

以甲基丙烯酸十二氟庚酯(DFM)单独作为助稳定剂进行苯乙烯半连续细乳液聚合,并对其最终乳液成膜表面进行疏水性能研究。考察了不同DFM用量作为助稳定剂对苯乙烯细乳液聚合过程中单体转化率、初始单体液滴粒径和数目、最终乳胶粒子粒径和数目的影响及成核机理研究;并采用含氟混合单体的细乳液组分进行半连续细乳液聚合。结果表明:细乳液聚合中,当DFM用量在15%(wt)时,最终乳胶粒子数目和初始液体数目比值为1.03,说明细乳液聚合以单体液滴成核为主体。在半连续聚合中,在苯乙烯94.0%转化率滴加细乳液组分产生次生粒子的比例仅为0.05;对其乳胶粒子成膜表面进行研究,发现水接触角可达113±2°。半连续细乳液聚合有效降低DFM用量,成膜表面疏水性良好。     

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。