Semi-continuous emulsion copolymerization of butyl methacrylate with polymerizable anionic surfactants

Two polymerizable anionic surfactants sodium 4-(ω-acryloyloxyalkyl)oxy benzene sulfonate (SABS-n, n=8 or 10) have been successfully used in the semi-continuous emulsion copolymerization with butyl methacrylate (BMA). After generating seeding particles in an emulsion consisting SABS-8 or SABS-10 and small amount of BMA using a redox initiator ammonium persulfate (APS)/tetramethylethylenediamine (TMEDA) at room temperature, most of BMA was added drop-wise to the polymerizing emulsion system during a period of 4-8 h. These emulsion copolymerizations produced nanosized latexes with high polymer/surfactant weight ratios up to about 12/1 and nearly monodisperse particles ranging from 18 to 33 nm in diameter. X-ray photoelectron spectroscopy results showed that SABS-n was significantly enriched on the surface of latex particles. The effects of concentrations of SABS-n, BMA, and APS/TMEDA and the latex characteristics during the continuous addition of monomer were studied. A possible polymerization mechanism was proposed.     

Near infrared light-induced disassembly of polymeric micelles based on methylene blue conjugated polyethylene glycol

Light-sensitive drug delivery systems are considered ideal for applications in the biomedical fields for their ability to release the payload in an on-demand spatiotemporal controlled manner through the manipulation of the light source. Among the broad radiation spectrum, near infrared (NIR) light is considered advantageous compared to UV and visible light, due to its inherently lower photodamage to normal tissues and deeper penetration to lesion areas. In this study, we report a successful synthesis of a polymer capable of undergoing partial degradation upon irradiation with NIR light by conjugating 10-N-carbamoyl linkage methylene blue (MB) moiety, a NIR photocleavable ligand, with polyethylene glycol (PEG). Through effective coupling of MB, a hydrophobic moiety, to the hydrophilic PEG molecule, an amphiphilic polymer was synthesized, as demonstrated by a lowered surface tension (55 mN/m at 0.1% wt/vol). Subsequently, photo-induced reversal of surface activity associated with self-assembled structure disruption, was displayed by surface tension measurements, size distribution analysis, and burst release profile of paclitaxel (PTX) from polymeric micelles upon the exposure to NIR irradiation.     

氟硅酸钠的防结块研究

分折了氟硅酸钠结块的原因，介绍了防结块的措施，并对表面活性剂和惰性物质应用于氟硅酸钠的防结块进行了研究。结果表明，硫酸巴盐或磺酸盐型表面活性剂应用于氟硅酸钠的防结块效果显著，选用复配型表面活性剂，即磺酸盐和脂肪酸盐等的复配液效果更佳，用量为0．12％时能确保氟硅酸钠70d不结块。     

脂肪醇聚氧乙烯-3-醚琥珀酸单酯磺酸盐泡沫性能研究

用罗氏法对脂肪醇聚氧乙烯 3 醚琥珀酸单酯磺酸钠(AESM 3)表面活性剂的泡沫性能进行了系统研究,测定了其在不同浓度、不同温度、不同硬度水中的泡沫性能,并与两种同类表面活性剂的泡沫性能进行了对比。结果表明,AESM 3是一种起泡性与稳泡性皆优的高泡性表面活性剂品种。     

甲烷水合物储气实验研究

利用甲烷水合物储气的实验装置，对高纯度甲烷（甲烷的体积分数为99.9%)气体的水合物形成过程进行了初步的实验研究，获得了水合物形成过程的耗气速度、储气密度与水合物形成条件（压力、表面活性剂种类、水量）的关系。研究结果有利于水合物储存天然气技术的推广和应用，对实现水合物技术的开发、利用和进一步研究水合物形成动力学具有重要价值。     

阴离子表面活性剂测定过程中有关问题的探讨

就亚甲蓝分光光度法测定阴离子表面活性剂应注意的有关问题进行了探讨，改进了测定的方法，具有简便良好的准确度和精密度。     

表面活性剂催化硝化TAIW制备CL-20

针对工业混酸法制备CL-20废酸污染大及N2O5/HNO3法收率低的现状,研究将成本低廉的表面活性剂引入到CL-20制备中,可大幅度提高产品收率。文章考察了表面活性剂种类、用量、反应时间及反应温度的影响,当反应温度为80℃,反应时间为4 h,物料比m(SDSN)m(TAIW)m(N2O5)V(HNO3)=0.3 g3.0 g4.0 g15.0 m L时,CL-20收率为89.6%,纯度为95.1%。该方法收率高,成本低,污染小,催化剂无需回收,有较强的应用前景。     

Improving the properties of water-borne pressure sensitive adhesives by using non-migratory surfactants

The adhesive performance of high solids content water-borne acrylic pressure sensitive adhesives synthesized using polymerizable surfactants (Latemul^®PD-104 and Sipomer^®Pam-200) or a polymerizable stabilizer (Sipomer^®Cops-1) has been studied. The use of a high pH during the polymerization process has a deleterious effect on the final adhesive properties because gel polymer is not formed. Interestingly, at low pH it is found that the surfactant concentration used during the polymerization process has also an effect on the polymer microstructure; the higher the surfactant concentration, the higher the final gel content of the latex. When polymerizable surfactants or a stabilizer are used the peel strength of the final films is considerably improved due to the surfactant incorporation into the polymer backbone and hence reduced surfactant migration to the air-film interface. Work of adhesion and shear adhesion failure temperature (SAFT) are not noticeably affected by surfactant migration but their performance is affected by the surfactant employed.     

Synthesis of Quaternary,Long-Chain N-Alkyl Amides and Their Corrosion Inhibition in Acidic Media

New cationic surfactants were synthesized by the quaternization of a number of straight-chain amide derivatives with triethylamine or pyridine. The corrosion inhibition tests of the surface-active compounds were performed at room temperature for 24 h on carbon steel coupons in acidic media using the gravimetric method. The acidic media used were 1.5 M HCl and 1.5 M H₂SO₄. Almost all of the synthesized cationic surfactants showed efficient inhibition of corrosion in the test. To establish the inhibition efficiencies of the inhibitors, surface characterization studies (contact angle measurements, SEM analysis and optical profilometer images) of the metal coupons used were performed.