醋酸丁酸纤维素与聚丙烯酸乙醋共混体系的研究

通过差热分析和拉伸试验研究醋酸丁酸纤维素ＣＡＢ－３５－１与了聚丙烯酸乙醋物理共混，半一互穿网络共混体系的相容性和力学性能，并用扫描电镜观察了共混物的形态。     

反应型增容剂PS-co-GMA在PA1010/ABS共混体系中的增容作用

以ＰＳ－ｃｏ－ＧＡＭ作为ＰＡ１０１０／ＡＢＳ共混体系的增容剂,探讨了增容剂的含量对共混体系力学性能的影响,同时,利用熔融共混法制备了ＰＡ１０１０／ＡＢＳ－ｇ－ＧＭＡ共混体系,比较了两种增容方式对共混体系力学性能的影响。     

SEBS在PP共混物中的研究进展

综述了氢化苯乙烯－丁二烯－苯乙烯嵌段共聚物作为塑料改性剂和共混相容剂，在聚丙烯及其共混物中对共混体系的屈服，冲击，断裂力学等性能的影响及研究进展。     

三元反应型增容剂PS-MAH-GMA在PA1010/ABS共混体系中的增容作用

以PS－MAH－GMA作为PA1010／ABS共混体系的增容剂，探讨了增容剂对共混物的力学性能的影响，结果发现：PS－MAH－GMA作为一种反应型增容剂，对于PA1010／ABS共混体系有较好的增容效果，可提高共混体系的力学性能。     

立构嵌段聚丁二烯的研制Ⅳ．立构二嵌段与三嵌段共混聚丁二烯的研究

在以ｎ－Ｂｕｌｉ为引发剂，环己烷为溶剂，二哌啶乙烷和二乙基锌为调节剂的丁二烯负离子聚合过程中，采用高分子设计，分别以二甲基二氯硅烷、苯甲酸乙酯和乙酸乙酯为偶联剂，合成了不同分子量、不同嵌段比及共混比的１，４－１，２／１，４－１，２－１，４及１，２－１，４／１，２－１，４－１，２立构嵌段聚丁二烯（ＰＢ），考察了共混物的微观相分离、流变性及屈服强度。结果表明，嵌段共混ＰＢ的分子量、嵌段比、共混比值只有在一定范围时，共混物才产生微观相分离，分相的嵌段共混ＰＢ具有较好的流变性、加工性，较小的冷流性和较高的屈服强度。     

LLDPE／LLDPE—g—AA共混物的接触角及红外光谱表征

利用熔融共混的方法制备了红性低密度聚乙烯（ＬＬＤＰＥ）／红性低密度聚乙烯接枝丙烯酸（ＬＬＤＰＥ－ｇ－ＡＡ）共混物。用ＦＴ－ＩＲ和测接角解的方法对不同ＬＬＤＰＥ－ｇ－ＡＡ含量的ＬＬＤＰＥ／ＬＬＤＰＥ－ｇ－ＡＡ共不昆物膜的表面进行了表征。随着共混物中ＬＬＤＰＥ－ｇ－ＡＡ含量的增加,水和甘油等极性液体在共混物表面的接触角下越小,羧基峰强度越大。     

PP—gMAH原位反应增容PP／PA—6共混纤维的研究

为探索聚丙烯（ＰＰ）纤维纺后染色的新途径，将少量尼龙－６（ＰＡ－６）与聚丙烯共混，并用马来酸酐枝聚丙烯（ＰＰ－ｇ－ＭＡＨ）对该共混物进行反应性增容，得到了较为满意的结果。本文着重研究了ＰＡ－６用量在２０％以下时，增容剂用量及不同ＰＰ／ＰＡ－６共混比对共混物的亚微形态，流变性能，结晶性能等的影响，并对共混物的染色性能和了初探讨。     

动态硫化SBR/PP共混物力学性能的研究

研究了不同共混比,不同类型SBR及不同硫化体系对动态硫化SBR／PP共混物力学性能的影响,试验结果表明,SBR／PP共混物的最佳共混比为60／40,E－SBR／PP共混物的力学性能稍好于S－SBR／PP共混物;采用硫黄硫化体系的共混物的力学性能优于采用过氧化物和酚醛树脂硫化体系的共混物;动态硫化SBR／PP共混物的交联密度低于静态硫化SBR母炼胶的交联密度。     

PP—g—AA对PP／云母增容作用的研究

研究了聚丙烯（ＰＰ）与云母共混时，添加第３组分ＰＰ－ｇ－ＡＡ对ＰＰ／云母共混体系的影响。用扫描电镜观察共混体系中云母的分布状况，研究结果表明，加入第３组分增加了共混体系的相容性，使拉伸强度和抗冲击强度均明显提高。     

配合剂和共混工艺对PVC／POM／NBR三元共混弹性体性能的影响

在制备PVC／POM／NBR三元共混弱性体的研究基础上,进一步探讨了防老剂品种及用量、炭黑品种及用量、增塑剂品种、共混工艺等因素对共混物力学性能的影响。结果表明：选择PVC／POM／NBR（20／10／70）100,半补强炭黑30－45,防老剂MB1.0－1.5,硫黄硫化体系及适量DOP,并选择共混温度175－180℃,共混时间4－5min以及采用先将PCV与NBR制成二元共混物再与已塑化的POM共混制成三元共混物为共混工艺,可制得综合性能较佳的PVC／POM／NBR三元共混弹性体。     

Physical properties of poly(ethylene adipate)/low-density polyethylene blends

Mechanical and rheological properties of poly(ethylene adipate) (PEA)/low-density polyethylene (LDPE) blends were investigated. DSC results showed that there is no miscibility between PEA and LDPE. Tensile strength decreases with increasing PEA content, while the modulus increases. Elongation at break decreases with increasing PEA content. A rheological constitutive equation was used for describing and predicting the steady-state shear viscosity of PEA/LDPE blend. The suggested equation was successfully able to describe and predict viscosity of the blend as functions of shear rate and temperature. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:1745–1750, 1997     

Effects of solid substrate on structure and properties of casting waterborne polyurethane/carboxymethylchitin films

We prepared two series of semiinterpenetrating polymer network (semi-IPN) films from cross-linked waterborne polyurethane (WPU) and carboxymethylchitin (CMCH) in the aqueous solution on the glass and Teflon as the hydrophilic and hydrophobic substrates, respectively, by casting method. The chemical compositions, structure and morphologies of the films were examined by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and scanning electron microscopy (SEM). The miscibility, thermal stability and mechanical properties of the films were investigated by density measurement, dynamic mechanical analysis (DMA), ultraviolet (UV) spectroscopy, thermogravimetric analysis (TGA), tensile testing and solvent swelling testing. The results revealed that the semi-IPN films exhibited good miscibility when CMCH content was lower than 35 and 65 wt% for the films prepared on the glass and Teflon, respectively, resulting in higher light transmittance, thermal stability and tensile strength than the WPU film. Interestingly, the films prepared with the Teflon as the substrate possessed better miscibility and higher storage modulus, thermal stability, tensile strength and solvent-resistance than that with the glass as the substrate over the entire composition range studied here. This difference can be attributed that a strong intermolecular interaction occurred between WPU and CMCH to form a dense architecture, owing to that two kinds of macromolecules all were repulsed from the Teflon surface and forced to concentrate into inner surface. It has been confirmed that the hydrophility and hydrophobility of the solid substrate significantly influenced the structures and properties of the casting films, and using Teflon solid substrate can more effectively improve the miscibility and properties of the semi-IPN materials with hydrophilic character than glass one. We proposed a model describing the formation of WPU/CMCH semi-IPN films cast on the hydrophilic and hydrophobic substrates to illustrate the different structures of two types of films.     

水滑石/膨胀型阻燃剂复合体系改性LDPE/EVA共混物研究

以氯磷酸二苯酯、乙二胺等为原料,合成了膨胀型阻燃剂N,N′-双(二苯氧基磷酰基)-2,2′-乙二胺(PEA),水滑石(LDH)与PEA复配阻燃改性低密度聚乙烯(LDPE)/乙烯-醋酸乙烯共聚物(EVA)共混物。结果表明,当LDPE/EVA/LDH/PEA的质量比为80/20/20/10时,所得复合材料的阻燃等级可达到UL94 V-1级别,极限氧指数(LOI)达28.3%;LDH与PEA复配使用提高了LDPE/EVA共混物热分解残留率;LDH和PEA协同作用强化了炭层,提高了复合材料的阻燃性能。     

Synthesis of IPN-related materials from solution of polyacrylates

IPN-related materials were synthesized from solution of two acrylate polymers having epoxide. From the dynamic mechanical spectroscopy, it was difficult to distinguish IPN or semi-IPN from mechanical blend in the case of PEMA/P2EHMA system. But some possibility of IPN phenomenon was observed. In the case of PEMA/PEA system, IPN synthesized from benzene-chloroform mixed solvent showed phase separation with the matrix of PEMA. IPN synthesized from xylene, however, showed phase separation with the matrix of PEA and the transition due to PEA shifted higher by 5°C than that of homo PEA. From the results, we concluded that PEMA/PEA system synthesized by xylene showed JPN phenomenon.     

Miscibility and lower critical solution temperature type phase behavior of poly(ethyl acrylate)/poly(vinylidene fluoride-cohexafluoro acetone) blends

Summary The miscibility of mixtures of poly(ethyl acrylate) (PEA) with poly (vinylidene fluoride-co-hexafluoro acetone) (P(VDF-HFA)) was investigated with optical microscopy and differential scanning calorimetry (DSC). In PEA/P(VDF-HFA) blends with P(VDF-HFA) content of 50 and 70(wt%), the heterogeneous phase morphology was observed on optical micrographs at 210°C. It was found that PEA/P(VDF-HFA) blends showed the lower critical solution temperature type (LCST) phase behavior. The endothermic peak for PEA / P(VDF-HFA) blend observed on DSC thermogram near 200°C corresponded to the liquid-liquid phase transition temperature as shown in the heterogeneous phase morphology with optical microscopy. It was expected that the endothermic peak is the transition temperature from miscibility to immiscibility.     

Miscibility of blends of epoxidized natural rubber and poly(ethylene-co-acrylic acid)

The blends of epoxidized natural rubber (50 mol %) (ENR) and poly(ethylene-co-acrylic acid) (PEA) (6 wt %) are demonstrated to be partially miscible up to 50% by weight of PEA and completely miscible beyond this proportion. The miscibility has been confirmed by a DSC study which exhibits a single second-order transition (T_g) for the 30 : 70 and 50 : 50 (ENR : PEA) blends. For the 70 : 30 (ENR : PEA) blend, the T_g's shift toward an intermediate value but do not merge to form a single T_g, making the blend partially miscible. The miscibility has been assigned to the esterification reaction between – OH groups formed in situ during melt blending of ENR and – COOH groups of PEA. The occurrence of such reactions have been confirmed by UV and IR spectroscopic studies. The existence of a single phase of the blends beyond 50 wt % of PEA has been shown by SEM studies. © 1995 John Wiley & Sons, Inc.     

Mechanical and thermal properties of poly(vinyl chloride)/α‐methyl‐styrene‐acrylonitrile blends prepared by melt extrusion

In this article, we have examined the physical and mechanical properties of poly(vinyl chloride) (PVC)/α‐methyl‐styrene‐acrylonitrile (αMSAN; 31 wt % AN concentrations) blends with different blend ratios. And, we also examined the effect of the molecular weights of PVC on the miscibility and material properties of the blends prepared by melt extrusion blending. Our results showed that the PVC/αMSAN blends have good processing properties and good miscibility over all blend ratios because of the strong interaction between PVC and αMSAN. And, the blends showed enhanced mechanical and thermal properties. In addition, high molecular weight PVC showed reasonable processability when melt blended with αMSAN, which resulted in enhanced mechanical and physical properties. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Morphology and mechanical properties of semi-interpenetrating polymer networks from polyurethane and benzyl konjac glucomannan

A series of semi-interpenetrating polymer network (semi-IPN) films coded as UB from castor oil-based polyurethane (PU) and benzyl konjac glucomannan (B-KGM) were prepared, and they have good or certain miscibility over entire composition range. Morphology, miscibility and properties of the UB films were investigated by using scanning electron microscopy (SEM), differential scanning calorimetry, dynamic mechanical analysis, ultraviolet spectrometer, wide-angle X-ray diffraction and tensile test. The results indicated that the UB films exhibited good miscibility when B-KGM content was lower than 15 wt%, resulting in relatively high light transmittance, breaking elongation and density. With an increase of the B-KGM content from 20 to 80 wt%, a certain degree of phase separation between PU and B-KGM occurred in the UB films. The tensile strength of the films UB increased from 7 to 45 MPa with an increase of B-KGM content from 0 to 80 wt%. By extracting the B-KGM with N, N-dimethylformamide from the semi-IPN, the morphology and phase domain size of the UB films were clearly observed by SEM. A continuous phase and dual-continuous phase model describing the semi-IPN were proposed to illustrate the morphology and its transition.     

The importance of enthalpic interactions in polymeric systems

Enthalpic interactions between blend components primarily determine the state of miscibility and many of the physical properties of the blend. Recent applications of these thermodynamic considerations are reviewed for a variety of systems, including binary and ternary blends of homopolymers, binary blends of copolymers with homopolymers, and polymer-solvent mixtures. Recent advances toward predicting polymer blend miscibility through use of a modified quasichemical thermodynamic model and heats of mixing data for liquids are also discussed.     

Characterization by Fourier transform infrared spectroscopy of polyethylene adipate/cholesteryl palmitate blends

FT‐IR spectroscopy has been employed to study compatibility, melting, and crystallization of the polyethylene adipate (PEA)/cholesteryl palmitate (CP) blends. The changes in FT‐IR spectra were followed by controlled rate of heating and cooling. The bands corresponding to the crystalline structure have been assigned. The accuracy of the transition temperature determination has been improved by fitting the curve of the integral absorbance dependence on temperature with a Boltzmann function. From dependence of the transition temperatures on the composition of the blend, it has been established that for each mixing ratio a certain mass fraction of CP should be dissolved in the PEA matrix. The PEA/CP blends behave as a phase‐separated system with partial miscibility. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1156–1163, 2004