超滤膜改性技术及其应用

综述了超滤膜改性国内外现状及研究进展，介绍了物理共混改性、化学改性、低温等离子体改性、高能射线辐照改性和紫外辐照改性等方法及其改性效果与特点．并指出这些方法的应用前景。     

聚四氟乙烯改性研究进展

从聚四氟乙烯的组成、结构、物理化学特性以及成型加工等方面说明对聚四氟乙烯进行改性的必要性；并对其表面改性、填充改性、共混改性等方法进行了详细的介绍，最后指出了聚四氟乙烯改性的新方向。     

改性聚酰胺纤维的开发现状及发展趋势

介绍了聚酰胺纤维的改性品种;详述了聚酰胺纤维的改性方法,其中物理改性主要有共混纺丝法、复合纺丝法、异形纺丝法及静电纺丝法,化学改性主要有共聚改性、交联改性、表面化学改性及络合改性,生物改性包括生物酶改性及生物基聚酰胺的合成;指出我国聚酰胺纤维的改性今后将朝着改性技术的多元化、服用性能的提升及产业用高性能纤维等方面发展,同时应加强改性产品的应用研究。     

酚醛树脂增韧及耐热改性研究进展

介绍了酚醛树脂在增韧改性、耐热改性等方面的研究进展。增韧改性方法包括:腰果油改性、丁腈橡胶改性、聚醚改性、聚酰胺改性等方法;耐热改性方法包括:硼酸改性、钼改性、有机硅改性、磷改性、聚砜改性等方法。     

我国改性聚氨酯的研究现状

综述了我国改性聚氨酯的主要分类,重点介绍了环氧树脂改性聚氨酯、聚丙烯酸酯改性聚氨酯、无机碳纳米管改性聚氨酯、有机硅改性聚氨酯等的研究进展,最后指出了我国改性聚氨酯今后发展方向。     

白炭黑表面改性处理的述评

文章介绍了白炭黑表面改性处理的机理,表面改性的方法与进展,从而述评了表面改性的紧迫性和可行性。     

聚丙烯的改性研究进展

文章介绍了聚丙烯(PP)化学改性和物理改性的各种方法,其中包括共聚改性、接枝改性、交联改性、共混改性、增强改性、填充改性,综述了各种改性方法的最新成果和研究进展。     

改性聚丙烯纤维研究进展

介绍了聚丙烯纤维改性方法 ,重点阐述了等离子体改性法、助剂改性法和共混改性法对聚丙烯纤维的改性以及改性后的聚丙烯纤维所具有的新性能 ;强调应加强等离子体改性法、助剂改性法等新型方法的研究 ,以便开发出多功能聚丙烯纤维。     

粉煤灰改性方法及其在废水处理中的应用

阐述了改性粉煤灰在污水处理的应用,分别从酸改性、碱改性、盐改性、联合改性以及其他改性方法5个方面介绍了粉煤灰的改性方法.综述了改性粉煤灰在处理染料污水、含重金属离子污水以及含氮含磷污水的应用进展.     

聚氯乙烯增韧改性研究新进展

综述了聚氯乙烯增韧改性的2种改性方法即物理共混改性法和化学交联改性法的研究进展,并介绍了聚氯乙烯增韧改性的机制。     

Competition between microphase separation and crystallization in self-assembly sPS/PS-PEP blends

The crystallization and the self-assembly of blending system, syndiotactic polystyrene/polystyrene-block-poly(ethylenepropylene) (sPS/PS-PEP), were investigated by transmission electron microscopy (TEM), polarized light microscopy, small angle X-ray scattering and differential scanning calorimetry (DSC). Spherical microdomains with sPS embedded in PS-PEP matrix were obtained after melt mixing as evidenced by TEM observations combined with DSC analyses. The size of spherical microdomains is in the order of tens nanometer. This unique morphology provides an appropriate system to examine the effect of crystallization on microphase-separated morphology. The driving force of sPS crystallization leads the growth of sPS crystals to overcome the effect of spatial confinement and the repulsive barrier of immiscibility, and thus to go across the surrounding PEP domains. As a result, the growth of crystallization interconnects sPS microdomains and forms crystalline lamellae. The overall crystallization rate of sPS in self-assembly sPS/PS-PEP blends increases with increasing the content of sPS. We suggest that the increase on the crystallization rate is attributed to the decrease on the crossing-distance between the crystallizing sPS domains due to an increase on the size of spherical microdomain.     

sPS/PBA-aPS共混物的结晶与熔融行为

通过熔融共混法制备了间规立构聚苯乙烯/聚丙烯酸丁酯无规立构聚苯乙烯核壳乳胶粒子（sPS/PBA-aPS）共混物,采用差示扫描量热仪、X射线衍射仪和偏光显微镜研究了PBA-aPS对sPS结晶性能、结晶形态的影响,以及共混物在不同降温速率下、等温结晶条件下所得试样的熔融行为。结果表明, PBA-aPS的引入对sPS的结晶起阻碍作用,sPS及其共混物存在明显熔融重结晶再熔融现象,sPS平衡熔点为293.2 ℃,共混物的平衡熔点随PBA-aPS含量增加而降低,sPS形成β型大球晶完善性变差,sPS/PBA-aPS共混物的冲击强度明显提高,sPS/PBA-aPS质量比为80:20时,冲击强度提高了117 %。     

Grafted syndiotactic polystyrene synthesized via melting graft copolymerization used as a compatibilizer for immiscible syndiotactic polystyrene/polyadimide 66 blends

A new grafted syndiotactic polystyrene (g‐sPS), to be used as a compatibilizer for syndiotactic polystyrene (sPS)/polyadimide 66 blends, was prepared by the melting graft copolymerization of sPS and monomers composed of itaconic acid and dibutyl maleate with dicumyl peroxide as an initiator. The resulting g‐sPS possessed a side‐chain structure identified by IR spectra, and the results of mechanical testing show that a good impact strength and tensile strength were obtained for g‐sPS at a 7.16‐phr addition of monomer with a 3:1 proportion of dibutyl maleate and itaconic acid. Differential scanning calorimetry and scanning electron microscopy analysis indicated that the g‐sPS maintained a high glass‐transition temperature and a crystalline structure. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1659–1666, 2005     

Syndiotactic polystyrene‐b‐atactic polypropylene block copolymer alloy as a compatibilizer for syndiotactic polystyrene/isotactic polypropylene blends

A polymeric alloy (SP–A) containing syndiotactic polystyrene (sPS), atactic polypropylene (aPP), and about 66 wt % sPS‐b‐aPP diblock copolymer, was prepared by the sequential feed of monomers in the presence of the half‐titanocene Cp*Ti(OBz)₃ (where Cp* is C₅Me₅ and Bz is PhCH₂), modified methylaluminoxane, and external triisobutylaluminum. The effects of the SP–A alloy as a compatibilizer for sPS and isotactic polypropylene (iPP) blends were evaluated. The blending of sPS and iPP, with and without SP–A, was performed in a single‐screw miniextruder with a side channel that allowed the continuous recycling of materials. The influence of SP–A on the mechanical and thermal properties of the immiscible sPS/iPP blends was investigated over a range of composition. The presence of the SP–A alloy resulted in a significant improvement of the impact strength of the blends compared with that of pure sPS and their pure blends. This improvement was particularly obvious in the sPS/iPP (90/10 wt %) blend containing 5 wt % SP–A. Morphological analysis of the impact‐fractured surface of the ternary blends indicated that the sPS‐b‐aPP diblock copolymer contained in the SP–A alloy acted as an efficient compatibilizer by decreasing the dispersed‐phase iPP particle size, improving the interfacial adhesion, and generating a stable microphase‐separated state. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1596–1605, 2003     

Effect of heat treatment on the microstructural change of syndiotactic polystyrene/poly(styrene-co-vinyloxazolin)/clay nanocomposite

The fabrication of a syndiotactic polystyrene (sPS)/organoclay nanocomposite was conducted via a stepwise mixing process using poly(styrene-co-vinyloxazolin) (OPS), i.e. melt intercalation of OPS into organoclay followed by blending with sPS. The effects of several parameters, including type of organoclay and mixing temperature on the microstructure of the nanocomposite were investigated through X-ray diffraction patterns and rheological properties. The microstructure of the nanocomposite mainly depended on the arrangement type of the organic modifiers in the clay gallery. Using organoclays having lateral a bilayer arrangement exfoliated structure was obtained, whereas intercalated structure were obtained when organoclay with a paraffinic monolayer arrangement was employed in our sPS/OPS/organoclay system. In this work, a simple heat treatment on a previously prepared OPS/organoclay nanocomposite induced microstructural evolution with a favorable direction from intercalation to exfoliation. This phenomenon is attributed to a strong interaction between OPS and the clay surfaces, which is revealed by plateau behavior of the storage modulus in rheological properties. When heat is applied to the OPS/organoclay, the OPS chains and clay layers move together by promoted thermal motion of OPS chains, which results in disordering of stacked clay layers and exfoliation.     

Carbon nanocapsules-reinforced syndiotactic polystyrene nanocomposites: Crystallization and morphological features

Syndiotactic polystyrene (sPS) composites filled with well-dispersed carbon nanocapsules (CNC) were prepared through solution blending along with ultrasonication. Several analytic techniques, including DSC, FTIR, PLM, WAXD, TEM, and TGA were performed to reveal the CNC effects on the crystallization, morphology and the thermal degradation of the as-prepared sPS/CNC composites. Addition of CNC was found to favor the crystalline modification of β-form sPS and depress the α-form ones. For the dynamic crystallization, a gradual reduction of cold-crystallization temperature of the α-form sPS was observed by increasing the CNC content although the glass transition temperature remained unchanged (∼96 °C). In contrast, the melt-crystallization temperature of the β-form sPS was elevated from 238 °C for the neat sPS to 251 °C for the 99/5 composite in spite of the fact that the equilibrium melting temperature (∼290 °C) determined from the linear Hoffman-Weeks plot was irrelevant with CNC concentrations. The former was attributable to the formation of an effective heat-conduction path to trigger an earlier overall crystallization. On the other hand, the latter resulted from the enhanced nucleation sites due to the presence of uniformly dispersed CNCs. Results of the isothermal crystallization of the β-form sPS concluded that the presence of 1% CNCs led to a significant increase in the crystallization rate as much as an order of magnitude. Moreover, the Avrami exponent changed to ∼2.0 from a value of 2.8 for the neat sPS, suggesting a different crystallization mechanism involved. At a given crystallization temperature, PLM results showed a negligible variation in the crystal growth rates and a decrease in spherulitic sizes, indicating that nucleation played the key role in enhancing the crystallization rate. For samples isothermally crystallized at 260 °C, the lamellar thickness was constant to be ∼7.2 nm regardless of the CNC content. Due to the enhanced nucleation, however, lamellar stacks were more randomly oriented and its lateral dimensions became shorter with increasing CNC contents. For composites with more than 1 wt% CNC, the crystallizability of sPS chains was reduced and the annealing peak located ca. 4 °C higher than the crystallization temperature became more evident, suggesting the plausible formation of micro-crystals in between the lamellar stacks. The TGA results illustrated that a better thermal stability was reached for the CNC-filled sPS composites.     

纳米SiO2改性丙烯酸酯乳液的工艺研究

采用水溶性环氧树脂对纳米S iO2进行化学改性,有效改善了纳米S iO2的表面性能。通过原位聚合法和共混法制备纳米S iO2/聚丙烯酸酯复合乳液,发现纳米S iO2的加入明显改善了涂膜的硬度、附着力、拉伸强度和耐候性,原位聚合法制备的复合乳液综合性能优于共混法。     

乳液型聚丙烯酸酯医用压敏胶的改性研究

分别采用多步乳液聚合法和乳液共混法改性制备粘接性能较好的乳液型聚丙烯酸酯医用压敏胶。分析讨论了种子乳液的组成、预溶胀时间和预溶胀次数、引发剂种类、原位聚合温度等因素对压敏胶粘接性能的影响。结果表明,多步乳液聚合法是全面提高粘接性能的有效方法;而基于预乳化半连续聚合工艺的乳液共混法,仅在一定范围内有改性效果。     

纳米Si02改性丙烯酸酯乳液的工艺研究

采用水溶性环氧树脂对纳米SiO2进行化学改性，有效改善了纳米SiO2的表面性能。通过原位聚合法和共混法制备纳米SiO2／聚丙烯酸酯复合乳液，发现纳米SiO2的加入明显改善了涂膜的硬度、附着力、拉伸强度和耐候性，原位聚合法制备的复合乳液综合性能优于共混法。     

Structure and mechanical properties of uniaxially oriented films of syndiotactic polystyrene and poly(2,6‐dimethyl‐1,4‐phenylene oxide) blends

The structure and mechanical properties of highly oriented films of a miscible blend of syndiotactic polystyrene and poly(2,6‐dimethylphenylene‐1,4‐oxide) (sPS/PPO) were studied in the composition range of sPS/PPO = 10/0 to 5/5. The oriented films were prepared by stretching the amorphous films of the blends. Wide‐angle X‐ray diffraction and polarized FTIR spectroscopy were used to analyze the amount of mesophase and molecular orientation. Drawing of the amorphous films of sPS and sPS/PPO blend induced a highly oriented mesophase. The mesophase content increases with increasing draw ratio and becomes nearly constant above a draw ratio of 3. Under the same draw ratio, the mesophase content decreases with increasing PPO content. The orientation function in the mesophase is as high as 0.95–0.99 irrespective of the composition and draw ratio. On the other hand, the orientation of molecular chains in the amorphous phase and mesophase increases with increasing draw ratio, and it decreases with increasing PPO content. The drawn films of pure sPS show high strength and high modulus in the drawing direction, but exhibit low strength in the direction perpendicular to the drawing. In the case of sPS/PPO = 7/3 blend, however, the ultimate strength in the perpendicular direction was dramatically improved compared with that of pure sPS and the ultimate strength in the parallel direction was similar to that for the oriented pure sPS. The improved mechanical properties in the sPS/PPO blends were discussed in relation to the structural characteristics of the sPS/PPO blend system. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91:2789–2797, 2004