废聚苯乙烯泡沫塑料接枝丙烯酸丁酯改性白乳胶的研制

通过对聚苯乙烯泡沫塑料进行乳化研究，获得了稳定的聚苯乙烯乳液。再采用丙烯酸丁酯（BA）和功能单体对聚苯乙烯进行接枝改性，制成水乳型胶粘剂。研究了溶剂比、乳化剂与稳定剂用量、改性单体及功能单体的用量、引发剂及交联剂用量等因素对粘接性能的影响。     

低烟阻燃高抗冲聚苯乙烯的研究

用氢氧化镁（MH）和硼酸锌（ZB）与十溴二苯醚（DBDPO）－氧化锑或包覆红磷共同使用以阻燃高抗冲聚苯乙烯（HIPS）可使燃烧过程中的发烟量降低40％左右。与十溴二苯醚－氧化锑和包覆红磷体系相比，聚苯醚（PPO）和一种磷酸酯阻燃剂配合作用时HIPS的阻燃、抑烟作用以及对力学性能有较大改善作用。     

对塑料“白色污染”的认识及治理对策

塑料“白色污染”的治理对策应当是在所谓的“白色污染”持正确看法的前提下,以发展回收和再利用技术为主,辅之以社会行为和其他技术,针对不同种类的废弃塑料,提出相应的解决办法。最后还就聚苯乙烯（PS）泡沫塑料消泡回收及再利用的新技术做了介绍。     

Transitions from solid to liquid in isotactic polystyrene studied by thermal analysis and X-ray scattering

A three-phase model, comprising mobile amorphous fraction (MAF), rigid amorphous fraction (RAF) and crystalline fraction (C), has been applied to interpret the thermal transitions and structure of cold-crystallized isotactic polystyrene (iPS) from below the glass transition temperature, T_g, to above the melting point. Quenched amorphous iPS films were isothermally crystallized at different temperatures for 12 h. The fraction of crystalline phase, ?_c, was measured by differential scanning calorimetry (DSC), wide angle X-ray scattering and Fourier Transform infrared spectroscopy. The fraction of the mobile amorphous phase, ?_MAF, was obtained from the heat capacity increment at the glass transition temperature. In the three-phase model, the fraction of the rigid amorphous phase, ?_RAF, was found from 1−?_MAF−?_c. Specific heat capacity measurements by standard DSC confirm that the experimental baseline heat capacity conforms to a three-phase model for temperatures ranging from below T_g, up to the relaxation of RAF. The relaxation of RAF appears as a sigmoidal change in heat capacity accompanied by excess enthalpy, in which solid-like RAF is converted to an identical amount of liquid-like MAF.At temperatures above the relaxation of RAF, either one or two major crystal melting endotherms are observed in standard DSC, dependent upon crystallization temperature. However, using quasi-isothermal temperature modulated DSC, we always observed two reversing melting endotherms. The effects of annealing on iPS structure during the quasi-isothermal measurement were assessed using small angle X-ray scattering (SAXS). Combining the DSC and SAXS results, a model for the melting of iPS lamellae at low heating rates is presented.     

纳米TiO2／HIPS复合体系流变性能研究

研究了纳米TiO2含量、EvA蜡对纳米TiO2／HIPS体系的流变性能影响，以原子力显微镜表征样品表面质量及母料分散性，以UV-Vis表征样品表面的吸收谱图。结果表明复合体系的表观粘度受纳米TiO2含量的影响较小，在低含量的情况下，复合体系的表观粘度优于纯HIPS。EVA蜡可以在较大范围内调整复合体系的流变性能，在流动过程中，复合体系内纳米TiO2聚集结构可以被逐步破坏，从而使纳米TiO2得到良好分散。原子力显微镜测试表明，采用6份以上EVA蜡改性的纳米TiO2／HIPS体系做母料，可得到表观及分散性良好的制品。低纳米TiO2含量HIPS制品依然呈现纳米TiO2本体的光学吸收特性，其表面对可见光仍有较强的反射能力，而对紫外光却有较强的吸收能力。     

Preparation of a self‐compatibility alloy via a seed‐graft concentrated‐emulsion pathway

A novel polymerization procedure, the concentrated‐emulsion graft polymerization of styrene monomer with poly(butyl acrylate) seed, was proposed for the production of a self‐compatibility macromolecule alloy. The effects of the butyl acrylate content, sodium dodecyl sulfate concentration, and polymerization temperature on the graft ratio were investigated. Scanning electron microscopy, transmission electron microscopy, and impact strength were used to characterize the microstructure and mechanical performance of the self‐compatibility macromolecule alloy. The results showed that increasing the butyl acrylate content, reducing the sodium dodecyl sulfate concentration, and improving the polymerization temperature all favored an increased graft ratio, which resulted in increased impact strength of the self‐compatibility macromolecule alloy. Therefore, the concentrated‐emulsion polymerization method is particularly suitable for seed‐graft polymerization. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2915–2920, 2002; DOI 10.1002/app.10288     

CO2‐assisted polymer processing: A new alternative for intractable polymers

CO₂‐assisted polymer processing is proposed as an alternative route for intractable and high molecular weight polymers based on the plasticization effects of CO₂ and its direct effect on the melting behavior of semicrystalline polymers. A modified processing system was used to process a variety of polymers in the presence of high‐pressure CO₂. The system includes an extruder that was modified to allow for high pressures created by the injection of CO₂. The new design includes a modified feed section that allows a given mass of polymer to interact with CO₂ before and during the extrusion process. The inherent shear mixing and the presence of CO₂ allow for a specific control over the extrudate morphology. Results suggest that this alternative design provides a new and easy route to melt process high melt viscosity polymers of commercial importance, such as polytetrafluoroethylene (PTFE), fluorinated ethylene propylene copolymer (FEP), and syndiotactic polystyrene (s‐PS). The increased processability of these systems in CO₂ is related to the plasticization effect of CO₂ that was quantified through a depression in the glass‐transition temperature according to the Chow model. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1501–1511, 2004     

On‐line determination of the conversion in a styrene bulk polymerization batch reactor using near‐infrared spectroscopy

A fast on‐line method for measuring the monomer conversion of a styrene batch polymerization reaction with near‐infrared spectroscopy (NIR) has been developed. Multivariate calibration was performed, using polymer samples having temperatures around the set point of the batch reactor (75–85°C) and monomer conversions up to 35%. The calibration model was built in such a way that the effect of the temperature on the predicted conversion of the sample was minimized. The method was validated in a number of batch runs. In these runs, the batch temperature and molar mass distributions of the polymer were varied. At‐line size‐exclusion chromatography was used as a reference method for measuring the monomer conversion. Results show that on‐line conversion monitoring with NIR offered overall an excellent accuracy (～ 0.32% conversion). For high and low monomer conversions a small bias in the predicted conversion is present. The method proved to be insensitive to both relative large changes (10°C) of the batch temperature and to considerable changes of the molar mass distribution of the polymer. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 90–98, 2002; DOI 10.1002/app.10241     

Synthesis and dielectric properties of polystyrene‐clay nanocomposite materials

Polystyrene‐clay nanocomposite (PsCN) materials were synthesized and their properties of crystallinity, thermal behavior, and dielectric characteristics were investigated. A polymerizable cationic surfactant, [2‐(dimethylamino)ethyl]triphenylphonium bromide, was used for the intercalation of montmorillonite (MMT). The organophilic MMT was prepared by Na⁺‐exchanged MMT and ammonium cations of a cationic surfactant in an aqueous medium. Organophilic styrene monomers were intercalated into the interlayer regions of organophilic clay hosts followed by a free‐radical polymerization. Exfoliation to 2 wt % MMT in the polystyrene (PS) matrix was achieved as revealed by X‐ray diffraction (XRD) and transmission electron microscopy (TEM). Thermal properties by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were also studied. The dielectric properties of PsCNs in the form of film with clay loading from 1.0 to 5.0 wt % were measured under frequencies of 100 Hz–1 MHz at 25–70°C. A decreased dielectric constant and low dielectric loss were observed for PsCN materials. The dielectric response at low frequency that originated from dipole orientation was suppressed due to the intercalation of clay materials. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1368–1373, 2004     

夏热冬冷地区双面保温体系传热系数研究

本文通过改变挤塑式聚苯乙烯保温板的位置和厚度,测定了普通砖墙双面保温体系的传热系数.研究结果表明：设置双面保温体系的普通砖墙受热桥影响很小,能够较好地满足夏热冬冷地区的建筑节能标准和要求.