氧化石蜡微乳液的研制

对氧化石蜡制备微乳液进行了研究，考察了微乳液的配方组成、乳化工艺条件及石蜡氧化改性程度对制备氧化石蜡微乳液的影响，结果表明：石蜡通过适当的氧化改性，在乳化剂D用量超过改性石蜡重量的60％，乳化温度超过改性石蜡熔化温度的条件下，可以制备氧化石蜡微乳液。     

助乳化剂对双连续微乳液聚合稳定性的影响

采用电导法确定单相微乳液的相区发现，水相分率＜18wt%为反相微乳液，水相分率在18－80wt%的区域是双连续相，水相分率大于80wt%则为正相微乳液区。利用高效的KMnO4-H2C2O4氧化还原引发体系引发双连续微乳液聚合，通过改变体系中助乳化剂的含量，考察了微乳液聚合的稳定性，得到了透明多孔的聚合物材料，并对双连续微乳液初始组成对聚合产物孔结构的影响进行了初步探讨。     

环氧基改性有机硅乳液聚合中乳化剂对聚合物乳液稳定性的影响

采用微乳液聚合法由D4开环聚合，含环氧基团的硅烷偶联剂共聚改性，合成了透明的环氧基改性有机硅微乳液。讨论了乳化剂对聚合反应速率、聚合物乳液粘度、乳胶粒径、聚合物乳液稳定性的影响。结果表明，采用阳／非离子型复合乳化剂10％(对乳液质量)有利于聚合反应进行，得到的环氧基改性有机硅乳液稳定。该环氧基改性有机硅乳液已经投产使用。     

氨基硅油微乳液的制备

微乳液是现在有机硅助剂的主要应用形式。综述了氨基硅油微乳液的制备;介绍了低变黄、亲水性和季铵化等再改性氨基硅油微乳液;指出了改性硅油微乳液存在的问题;并提出了在氨基硅油改性及其微乳液制备中面临的新课题。     

微乳液在化妆品及洗涤剂中的应用

阐述了微乳液的性能，用Winsor的R比理论解释了微乳液的形成机理，简述了微乳液的制备；详细综述了微乳液在化妆品及洗涤剂当中的应用。利用微乳液的一些特殊的性质，如超低的界面张力、增溶性、热力学稳定和光学上透明，将其用于化妆品和洗涤剂中可以制得性能优良的产品。同时概述了无中等链长醇的微乳液在洗涤剂中的应用。     

氨基改性有机硅微乳液的制备及应用进展

着重阐述了氨基改性有机硅微乳液的各种制备方法以及它们各自的特点。氨基改性有机硅微乳液兼具聚硅氧烷和氨基的双重性质,从而具有链段柔顺性、耐热性、润滑性、反应性和吸附性等特点。介绍了氨基改性有机硅微乳液在化妆品、织物整理、皮革涂饰、纸浆造纸和汽车抛光等方面的应用。     

氨基有机硅微乳液的合成及性能研究

本语文介绍了通过预乳化再开环聚合制得氨基改性有机硅微乳液合成工艺,并对所得微乳液的性能进行了测试,指出了预乳化,滴加速度、乳化剂的选择与复配、ＰＨ值及水硬度均影响氨基改性有机硅微乳液的形成。     

涂料用有机硅改性丙烯酸酯乳液的研究进展

介绍了合成丙烯酸酯乳液的原料以及方法、有机硅改性丙烯酸酯乳液(硅丙乳液)的改性方法,以及有机硅改性丙烯酸酯微乳液的发展状况,并对硅丙乳液的发展前景进行展望.     

改性石蜡微乳液的制备

采用聚乙烯蜡对石蜡进行催化氧化改性,对改性石蜡制备微乳液进行了研究,考察了微乳液的配方组成以及乳化条件对制备微乳液的影响.结果表明当蜡样、乳化剂的质量比为1:0.60,乳化时间为50 min,乳化温度为90～95 ℃,搅拌速度为1 200～1 500 r/min 时可得到稳定的蜡微乳液.     

改性皂化蜡微乳液的制备

将皂化蜡进行催化氧化改性,对改性皂化蜡制备微乳液进行了研究,考察了微乳液的配方组成以及乳化条件时制备氧化皂化蜡微乳液的影响.研究结果表明:当m(改性皂化蜡):m(乳化剂):m(助乳化剂)=1:0.40:0.02,乳化时间为30 min,乳化温度为85～90℃,搅拌速度为(1 000～1 200)r/min,得到稳定的蜡微乳液.     

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.     

Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.     

Highly moisture-proof polysilsesquioxane coating prepared via facile sol-gel process

A highly moisture-proof polysilsesquioxane coating was obtained from a new bis-silylated precursor, which was synthesized from 3-aminopropyltriethoxysilane (APTES) and m-xylylene diisocyanate (m-XDI) in tetrahydrofuran (THF) and verified by ¹H MAS NMR. For direct comparison purposes, an SiO₂ coating was also prepared by the Stöber method using tetraethoxysilane (TEOS) as the reactant. Interestingly, the coating obtained from the polysilsesquioxane sol exhibited a much higher moisture resistance capability than its counterpart, which was attributed to its more compact feature between nanoparticles as characterized by N₂ absorption experiment and transmission electron microscopy (TEM). Furthermore, its high transparency of about 92% showed potential for application in the protection of optical crystals.