吸水树脂PAA／AM的合成研究

以N，N-亚甲基双丙烯酰胺（Bis）为交联剂，过硫酸钾（KPS）做引发剂，以丙烯酸（AA），丙烯酰胺（AM）为反应单体水溶液聚合法合成了适用于淡水和盐水的吸水膨胀聚合物。采用正交实验法对最佳吸水膨胀配方进行了优选：单体浓度[M]=30％；单体中和度N=75％；引发剂浓度[I]=0．15％；交联剂浓度[C]=0.011％；反应温度为75℃及反应时间3h。对PAA的吸液速率进行了测定，并讨论了它的反复吸液能力。     

负载钛酸酯催化剂催化合成己二酸二异辛酯

聚乙烯醇与四氯化钛在二甲基亚砜和无水乙醇的混合溶剂中反应，制得负载钛酸酯催化剂PVAC-1，用红外光谱对其进行了表征。结果表明：合成中投入3g聚乙烯醇，3mL四氯化钛时，过程容易控制，且催化剂的活性已达很高。确定了在PVAC-1催化作用下，合成己二酸二异辛酯的最佳反应条件及结果：即200℃～210℃下，加入0.3g催化剂，0．1mol己二酸与0．3mol异辛醇反应60min后，己二酸的转化率可达99．7％，PVAC-1重复使用16次后，己二酸的转化率仍保持在96％以匕。     

Large macro-dipoles generated in a supramolecular polymer of N,N′,N″-tris(3,7-dimethyloctyl)benzene-1,3,5-tricarboxamide in n-decane

A supramolecular polymer formed by N,N′,N″-tris(3,7-dimethyloctyl)benzene-1,3,5-tricarboxamide (DO₃B) in n-decane (C₁₀) possesses large macro-dipoles naturally generated by three-fold inter-molecular hydrogen bonding aligned along its helical columnar structure connected by defective portions, which are DO₃B molecules containing failure in the hydrogen bond formation, in the order of head to tail arrangement without dipole inversion like type-A polymers.     

Amphiphilic segmented polymer networks based on poly(2-alkyl-2-oxazoline) and poly(methyl methacrylate)

Amphiphilic segmented polymer networks (SPNs) have been prepared by free radical copolymerization of methyl methacrylate with α,ω-bisacrylate terminated poly(2-methyl-2-oxazoline) and poly(2-ethyl-2-oxazoline). DSC and DMTA analysis demonstrated the influence of the copolymer composition, the molecular weight and nature of the poly(2-alkyl-2-oxazoline)s and the polymerization conditions on the final phase morphology of the networks. A comparative phase morphology study of the polymer blends and SPNs revealed the more compatible phase morphology of the networks. The compatibility could be further increased by UV-induced network formation. The investigation of the solvent uptake in different solvents clearly demonstrated the amphiphilic nature of the SPNs.     

新型合成聚合物重金属离子吸附剂及其吸附性能

阐述了新型聚合物重金属离子吸附剂的合成与改性及其对水溶液中Cd(Ⅱ)、Pb(Ⅱ)、Cu(Ⅱ)、Hg(Ⅱ)等重金属离子的吸附性能。这些聚合物重金属离子吸附剂对低浓度的重金属离子表现出了较好的吸附能力，其中聚合物吸附剂PGHyFeO—COOH对mg／L级的Pb(Ⅱ)、Cd(Ⅱ)、Hg(Ⅱ)的最大吸附量分别为211．4mg／g、155．0mg／g、147．2mg／g。这些吸附剂的吸附速度也较快，平衡吸附时间一般在60min左右，有的甚至只有几分钟。新型聚合物重金属离子吸附剂在水处理工业中具有广阔的应用前景。     

Structure and properties of nanocomposites based on poly(butylene succinate) and organically modified montmorillonite

Poly(butylene succinate) and organically modified montmorillonite nanocomposites with there different compositions were prepared via melt blending in a twin‐screw extruder. The structure of the nanocomposites was studied with X‐ray diffraction and transmission electron microscopy, which revealed the formation of intercalated nanocomposites, regardless of the silicate loading. Dynamic mechanical analysis revealed a substantial increase in the storage modulus of the nanocomposites over the entire temperature range investigated. The tensile property measurements showed a relative increase in the stiffness with a simultaneous decrease in the yield strength in comparison with that of neat poly(butylene succinate). The oxygen gas barrier property of neat poly(butylene succinate) improved after nanocomposite preparation with organically modified montmorillonite. The effect of the layered‐silicate loading on the melt‐state linear viscoelastic behavior of the intercalated nanocomposites was also investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 777–785, 2006     

Electrochemical characteristics of phase-separated polymer electrolyte based on poly(vinylidene fluoride-co-hexafluoropropane) and ethylene carbonate

A polymer electrolyte based on microporous poly(vinylidene fluoride-co-hexafluoropropane) (PVdF-HFP) film was studied for use in lithium ion batteries. The microporous PVdF-HFP (Kynar 2801) matrix was prepared from a cast of homogeneous mixture of PVdF-HFP and solvents such as ethylene carbonate (EC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC). After evaporation of DMC and EMC, a sold film of the PVdF-HFP and the EC mixture was obtained. EC-rich phase started its formation in the PVdF-HFP/EC film at EC content of about 60 wt.% based on the total weight of PVdF-HFP and EC. The formation of the new phase resulted in the abrupt increase of the porosity of the PVdF-HFP matrix from 32 to 62%. The ionic conductivity of the film soaked in 1 M LiPF₆-EC/DMC=1/1 was significantly increased from order of 10⁻⁴ S/cm to order of 10⁻³ S/cm at the EC content of 60 wt.%. Thermal and spectroscopic investigations showed that most of the EC interact with PVdF-HFP with the EC content being below 60 wt.%. MCMB/polymer electrolyte/LiCoO₂ cells employing the microporous PVdF-HFP polymer film showed stable charging/discharging characteristics at 1C rate and good rate capability.     

Enhanced thermal stability of poly(lactide)s in the melt by enantiomeric polymer blending

Poly(l-lactide) (i.e. poly(l-lactic acid) (PLLA)) and poly(d-lactide) (i.e. poly(d-lactic acid) (PDLA)) and their equimolar enantiomeric blend (PLLA/PDLA) films were prepared and the effects of enantiomeric polymer blending on the thermal stability and degradation of the films were investigated isothermally and non-isothermally under nitrogen gas using thermogravimetry (TG). The enantiomeric polymer blending was found to successfully enhance the thermal stability of the PLLA/PDLA film compared with those of the pure PLLA and PDLA films. The activation energies for thermal degradation (ΔE_td) were evaluated at different weight loss values from TG data using the procedure recommended by MacCallum et al. The ΔE_td values of the PLLA/PDLA, PLLA, and PDLA films were in the range of 205-297, 77-132, and 155-242 kJ mol⁻¹ when they were evaluated at weight loss values of 25-90% and the ΔE_td value of the PLLA/PDLA film was higher by 82-110 kJ mol⁻¹ than the averaged ΔE_td value of the PLLA and PDLA films. The mechanism for the enhanced thermal stability of the PLLA/PDLA film is discussed.     

Crystallization kinetics of low‐density polyethylene and polypropylene melt‐blended with a low‐Tg tin‐based phosphate glass

The nonisothermal and isothermal crystallizations of low‐density polyethylene (LDPE) and polypropylene (PP) in phosphate glass (Pglass)–polymer hybrid blends were studied through differential scanning calorimetry (DSC). As the Pglass volume fraction was increased, the percentage crystallinity decreased. The half‐time for crystallization decreased as the propagation rate constant rose, for both of the polymer matrices, with increasing Pglass concentrations. The Pglass was observed to be a nucleating agent for formation of two‐ or three‐dimensional spherulites in the hybrids. Tensile modulus improved for both of the Pglass–polymer hybrids up to 40% Pglass, but the energy to break decreased. Tensile strength changed slightly with the addition of Pglass to the LDPE matrix, exhibiting a larger value than that of pure LDPE at 30%. The tensile strength decreased as more Pglass was added to the PP matrix. The observed differences between tensile properties of the Pglass–PP and Pglass–LDPE hybrids at identical Pglass volume concentration were found to be consistent with that of the crystallization behavior of the hybrids. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3445–3456, 2003     

微孔发泡过程中聚合物/超临界CO2均相体系形成的研究

阐述以超临界CO2为发泡剂的微孔发泡中均相体系的形成过程，研究聚合物熔体和气体的混合机理，并分析影响均相体系形成过程的因素。结果表明，聚合物和气体本身的结构和性质、工艺条件、加工设备、外力场等均影响均相体系的形成，振动力场的引入可以提高多相体系的混合程度，在聚合物／气体均相体系的形成过程中引入振动力场是一个全新的研究方向。