Functional copolymer/organo‐MMT nanoarchitectures. II. Dynamic mechanical behavior of poly(MA‐co‐BMA)s‐organo‐MMT clay nanocomposites

Functional copolymer/organo‐silicate [N,N′‐dimethyldodecyl ammonium cation surface modified montmorillonite (MMT)] layered nanocomposites have been synthesized by interlamellar complex‐radical copolymerization of preintercalated maleic anhydride (MA)/ organo‐MMT complex as a ‘nano‐reactor’ with n‐butyl methacrylate (BMA) as an internal plasticization comonomer in the presence of radical initiator. Synthesized copolymers and their nanocomposites were investigated by dynamic mechanic analysis, X‐ray diffraction, SEM, and TEM methods. It was found that nanocomposite dynamic mechanical properties strongly depend on the force of interfacial MA … organo‐MMT complex formation and the amount of flexible n‐butyl ester linkages. An increase in both of these parameters leads to enhanced intercalation and exfoliation in situ processes of copolymer chains and the formation of hybrid nanocomposites. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

用高纯膨润土制备无机凝胶的工艺研究

以莱西钙基膨润土为原料,经二次湿法提纯-2μm的膨润土,钠化改型,制备了高纯度的钠基膨润土,在此基础上,探索了无机凝胶的制备工艺,考察了不同磷化剂和胶化剂对无机凝胶的影响。提出了以0.7%焦磷酸钠为磷化改性剂,1.5%CaO为胶化剂制备无机凝胶的新工艺。希望能代替进口的VEEGUM系列应用于日化工业。     

钠型累托石处理印染废水

文章的正交实验研究表明:(1)用改性累托石处理印染废水中的浊度及COD,在废水pH为5,改性累托石用量为110 mg/L,搅拌时间为20 min,搅拌速率为50 r/min时,最优化条件下,经验证实验,COD去除率可达50%。浊度去除率可达96,71%。(2)影响浊度去除率的因素主次顺序是:改性累托石用量pH搅拌速率搅拌时间。影响COD去除率的因素主次顺序是:改性累托石用量pH搅拌时间搅拌速率。     

一种重防腐涂料用复合流变剂的制备及性能研究

文章介绍了一种新型胶体复合流变剂的制备以及在重防腐涂料等高固含涂料体系中的应用。结果表明,该防沉剂能够有效的提高重防腐涂料的储存稳定性,提高防沉抗流挂效果,与普通膨润土流变剂相比,该防沉剂能够降低对涂料光泽度的影响。     

SRK方程结合超额Gibbs自由能规则预测汽液平衡

SRK方程结合范德华混合规则应用于极性体系会产生较大误差,而结合超额Gibbs自由能(GE)型混合规则能得较好的结果。Wong-Sandler(WS型)混合规则是基于无穷大压力的GE型混合规则,文中对提出一种基于常压的改进型WS(MWS型)混合规则,利用SRK方程分别结合WS型和MWS型混合规则对多个二元极性体系汽液平衡进行预测。比较结果表明,采用SRK方程结合MWS型混合规则预测汽液平衡结果一般优于WS型混合规则。     

改性聚苯胺膜在CO_2/CH_4分离中的应用研究

合成了一种由N-乙基苯胺和苯胺共聚的高聚物,并制备了其4种掺杂态共聚物膜。实验中在不同压力、不同进料组成下测试了共聚物膜及聚砜膜对CO2/CH4混合气的分离性能。实验结果表明:掺杂态不同对气体的分离性能有很大影响,其中二次掺杂态的分离系数最高,可达70,而去掺杂态的渗透速率最高,CO2可达2.15 GPU[1 GPU=7.501×10-10cm3/(cm2.s.Pa)],CH4达到0.049 GPU,均高于聚砜膜和文献中报道的聚苯胺膜的值,这是由于N-乙基的引入,改变了聚合物链的柔韧性。     

改性聚四氟乙烯膜精细过滤器处理油田含油污水探索性试验研究

试验根据大庆油田含油污水的水质特性,开展改性聚四氟乙烯膜精细过滤技术处理油田含油污水的探索性小型试验装置现场试验,通过试验确定改性聚四氟乙烯膜精细过滤应用于大庆油田含油污水处理技术上是可行的。现场试验结果表明,经改性聚四氟乙烯膜精细过滤处理后的出水水质能够达到大庆油田低渗透率油层回注水水质控制指标(即:含油质量浓度≤8.0mg/L、悬浮固体质量浓度≤3.0mg/L、颗粒粒径中值≤2.0μm),并初步确定了改性聚四氟乙烯膜精细过滤器的结构和设计参数,为下一步的放大试验奠定了基础。     

Promethazine determination in plasma samples by using carbon paste electrode modified with molecularly imprinted polymer (MIP): Coupling of extraction, preconcentration and electrochemical determination

A promethazine (PMZ) molecularly imprinted polymer (MIP) and a non-imprinted polymer (NIP) were synthesized by two different formulations of methacrylic acid-ethylene glycol dimethacrylate (MAA-EGDMA) and vinyl benzene-divinyl benzene (VB-DVB). Then, the MIPs were used to modify the carbon paste electrode (CP). The response difference between MIP-CP and NIP-CP electrodes, containing VB-DVB polymer, was higher than that for MIP-CP and NIP-CP modified with polymer of MAA-EGDMA, indicating the lower nonselective surface adsorption property of the VB-DVB based MIP. The MIP, incorporated in the carbon paste electrode, functioned as selectively recognition element and pre-concentrator agent for PMZ determination. The prepared electrode was used for PMZ measurement by the three steps procedure including analyte extraction in the electrode, electrode washing and electrochemical measurement of PMZ. It was shown that the electrode washing, after PMZ extraction, led to enhanced selectivity. Square wave voltammetry (SWV) for PMZ determination by proposed electrode was proved to be better than that of differential pulse voltammetry. Some parameters, effective on the electrode response, were optimized and then a calibration curve was plotted. Two dynamic linear range of 7 × 10⁻⁹ to 4 × 10⁻⁷ and 4 × 10⁻⁷ to 7 × 10⁻⁶ mol L⁻¹ were obtained. The detection limit of the method was calculated equal to 3.2 × 10⁻⁹ mol L⁻¹. This method was used successful for PMZ determination in blood serum sample.     

Highly Enantioselective Epoxidation of Unfunctionalized Olefins Catalyzed by Chiral Jacobsen’s Catalyst Immobilized on Phenoxy‐Modified Zirconium Poly(syrene‐phenylvinylphos‐ phonate)phosphate

Chiral Jacobsen’s catalyst was axially immobilized onto phenoxy‐modified zirconium poly(styrene‐phenylvinylphosphonate)phosphate (ZPS‐PVPA). The immobilized catalysts show comparable ee values for asymmetric epoxidation of styrene and much higher ee values for α‐methylstyrene (73.7% vs. 54.0%) and indene (99.9% vs. 65.0%) than the homogeneous Jacobsen’s catalyst. Moreover, the as‐synthesized catalysts are relatively stable and can be recycled at least five times without significant loss of activity and enantioselectivity. A point worth emphasizing is that the heterogeneous catalysts afforded remarkable increases of conversion and ee values in the absence of expensive O‐coordinating axial bases for the asymmetric epoxidation of olefins, especially for the epoxidation of α‐methylstyrene (conversion: from 24.3% to 99.9%; ee: from 29.4% to 73.7%), which may overcome the last obstacle for the potential industry application of chiral Jacobsen’s catalyst.     

纳米TiO_2改性有机硅粘接涂层的制备

用硅烷偶联剂对纳米TiO2进行表面改性,制备了具有亲油性的纳米TiO2粉体,并采用红外光谱(FT-IR)和电子扫描探针显微镜(AFM)对其结构进行了表征。将改性后的纳米TiO2通过机械共混的方式添加到有机硅粘接涂层中,研究了改性纳米TiO2对粘接涂层性能的影响,并对改性后的粘接涂层进行人工老化和自洁性检测。结果表明:当添加w(纳米TiO2)=1%~2%时,粘接涂层的综合性能最好;改性后的粘接涂层具有自洁性和超强的耐候性,经人工加速老化1 200 h后具有不变色、不起泡和不脱落等优点。