Effectiveness test of alginate‐derived polymeric surfactants

A series of alginate‐derived polymeric surfactants (APSs) with a linear alkyl group (C8, C12, C16) was synthesized by oxidation followed by reductive amination of 2,3‐dialdehydic alginate. The products were characterized by measuring IR spectra, NMR spectra, surface tension and critical micelle concentration (cmc). They were also tested for the solubilization of azobenzene and adsorption of heavy metal. In the case of 40% CHO‐C8 APSs, the lowest interfacial tension value (31.5 m Nm^?1) was obtained at the cmc value of 1.35 g dm^?3. The dissolving capacity of 40% CHO‐C8 APS towards azobenzene was 27 times greater than that of alginate. The overall cobalt (Co²⁺) removal efficiency by adsorption using APSs was high compared with that of sodium alginate at pH 3, 5 and 7. Equilibrium aspects of cobalt adsorption onto 10% CHO‐APSs were studied, and the results show that APSs had high equilibrium capacities for cobalt uptake, 115.5 mgg^?1. © 2002 Society of Chemical Industry     

对氨基苯甲酸生产废水的树脂吸附预处理

采用超高交联吸附树脂处理芳香两性化合物对氨基苯甲酸(PABA)生产废水,通过静态吸附、动态吸附-脱附实验,研究确定了最佳的吸附-脱附工艺条件。结果表明,在常温和2 BV/h的吸附流量条件下,原废水不用调节pH值,直接经JX-101树脂吸附处理20 BV后,CODC r可从6 000 mg/L左右降至700 mg/L左右,CODC r去除率达88%以上,PABA的吸附去除率达99%以上。采用1 BV 8%氨水溶液 1 BV 4%氨水溶液 2 BV水作脱附剂,在313 K脱附温度和1 BV/h脱附流量的条件下,树脂脱附性能良好。该工艺简单,运行稳定,操作简便,可回收有用物质,有望实现工业化。     

Environmentally benign precipitation copolymerization of methacrylate ester and styrene to make polymeric microspheres in supercritical carbon dioxide

The polymeric microspheres were synthesized by the precipitation copolymerization of glycidyl methacrylate (GMA) with methacrylic acid(MAA) or 2‐hydoxyethyl methacrylate (2‐HEMA) containing styrene (ST) in SC‐CO₂. Scanning electron microscopy (SEM) showed that the products were spherical microparticles, with the addition of MAA and/or 2‐HEMA as the monomer, with diameter of 0.2–2 μm. The effects of copolymerization pressure, temperature, and ratios of GMA/MAA, ST, and/or GMA/2‐HEMA, on the particle size and morphology were investigated in detail. A new experiment setup is proposed for the large amount of production, based on the rule of lower monomer concentration, more stable system, and better use of the present polymerization apparatus. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2425–2431, 2007     

Synthesis and characterization of polystyrene initiated using polymeric peroxide

Polymer peroxides were synthesized by copolymerizing tert‐butyl‐3‐isopropenylcumylperoxide (D‐120) with styrene (St). Exothermic peak at 192.7°C in DSC thermogram indicated that peroxy bonds in D‐120 remained intact during the copolymerizing process. The polymeric peroxide was used to initiate polymerization of St. GPC results showed that polystyrene (PS) initiated by the polymeric peroxides was composed of both linear and branched molecules. In addition, the rheology test showed that PS samples initiated by polymeric peroxide contained branched structure and had lower shear viscosities. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 197–202, 2006     

Surface activity and solubilization of a novel series of functional polyurethane surfactants

Functional polyurethane surfactants (di‐block and tri‐block) were synthesized by addition polymerization of 2,4‐toluenediisocyanate with poly(propylene oxide) and monoallyl‐end‐capped poly(ethylene oxide). The chemical structure of the polyurethane surfactants was confirmed by Fourier transform infrared and ¹H NMR spectroscopy. These polymeric surfactants were found to have excellent surface activity. The lowest surface tension of polyurethane surfactant aqueous solutions could be reduced to 37.6 mN m^?1. All the polyurethane surfactants synthesized had low critical micelle concentrations and could reduce the surface tension even at very low concentration levels (10^?6–10^?5 mol L^?1). The solubilization of toluene in micelles of the synthesized polyurethane surfactants was studied using UV‐visible spectroscopy, and the results showed that they all exhibited good solubilization capacity. Possible solubilization positions of toluene in the micelles are conjectured. Copyright © 2006 Society of Chemical Industry     

异养菌与自养菌对好氧颗粒污泥稳定性的影响

研究了异养菌和自养菌颗粒污泥的特性：与异养菌相比,自养菌颗粒污泥粒径小、密度大、胞外多聚物（EPS）含量高但强度小。通过对粒径、EPS等特性与密度的变化规律分析,研究发现,自养菌颗粒污泥的粒径与密实度呈现出一致性,颗粒趋于稳定;而异养菌颗粒污泥粒径成长同时伴随着密度减小,粒径与密实度呈现不一致性,颗粒容易解体。颗粒强度的分析结果表明：在自养菌系统中EPS与孔隙率能够达到动态平衡是其长期维持稳定的主要原因,而异养菌中粒径与孔隙率无法达到平衡,操作条件无法控制高强度丝状菌的繁殖是其不稳定的主要因素。     

偕胺肟基功能高分子膜吸附铀量的测定

以偶氮氯膦Ⅲ(CPAⅢ)作为显色剂,研究可见光分光光度计测定含偕胺肟基功能高分子膜螯合电极对铀酰离子的吸附量的实验方法。确定了分光光度法测定的铀酰离子吸附量的实验条件:吸收光波长670 nm,CPAⅢ标准溶液(0.001 mol.L-1)的用量3mL,测定体系的最佳pH值1.0,室温下显色时间2 min。在此实验条件下,绘制了铀的工作曲线,并得到摩尔吸光系数为ε=29 750 mol-1.L.cm-1。对比电子能谱法所测定的脱附铀前后的螯合电极表面的铀含量(脱附前后亮区铀含量分别为38.12%和6.29%,暗区铀含量都为零),得到分光光度计法测定的铀含量并不是螯合电板表面的真实铀含量,但却是脱附下来的铀的真实量,这肯定了分光光度法测定铀的吸附量优势所在。     

铌酸锂铁电薄膜的制备与表征

采用柠檬酸盐法制备铌酸锂铁电薄膜。探讨了柠檬酸（CA）和乙二醇（EG）的用量、pH和水浴温度等工艺参数对溶胶性能的影响。采用XRD和TG—DTA研究了铌酸锂（LiNbO3）晶相的形成过程，用XRD和AFM对所制得薄膜的物相组成和表面形貌进行了表征。结果表明，当前驱体溶胶的pH为7．5，水浴温度大于80℃，n（CA）：n（Li＋Nb）=3：1，n（CA）：n（EG）=1：2时，可以获得稳定性好的溶胶。薄膜经缓慢升温至800℃热处理，可以获得单相、表面光滑、晶粒大小均匀、晶粒大小为70nm的LiNbO3铁电薄膜。     

超临界条件下苯酚在NKA-Ⅱ树脂上的吸附相平衡

测定了苯酚在常规条件 (以水作为流体 )下在极性、弱极性和非极性吸附树脂上的吸附等温线 ,研究了“苯酚 +NKA -Ⅱ树脂 +超临界CO₂ ”体系的吸附相平衡关系 ,测定了苯酚在NKA -Ⅱ树脂上的超临界吸附等温线 ,考察了超临界条件下乙醇作为添加第三组分的对苯酚在NKA -Ⅱ树脂上的吸附等温线的影响 .结果表明 :苯酚在极性吸附树脂上的平衡吸附量要远大于在弱极性和非极性吸附树脂上的平衡吸附量 ,在超临界条件下 ,苯酚在树脂上的吸附量远小于在常规条件 (如水作为流体 )苯酚在树脂上的吸附量 ,而且乙醇的添加又将能改变超临界吸附相平衡 ,使苯酚在NKA -Ⅱ树脂上的平衡吸附量进一步减少 .可以利用这些特性开发超临界流体再生吸附剂技术     

反应型聚合物稳定剂的研究进展

通用塑料在阳光作用下都会降解，添加稳定剂可成功地解决此问题。但是，在某些情况下普通的稳定剂不能满足这种要求，这就促进了新的反应型稳定剂的发展。低分子稳定剂的接枝可克服草取问题。研究反应型稳定剂是提高聚合物的耐热性和耐草取性的一种发展趋势。按反应性基团的不同，该类稳定剂可分为乙烯基型、丙烯酰基型和其他类型。文章综述了反应型稳定剂的合成和应用，还介绍了其中一些商业化的品种。