醋酸纤维素／聚乙烯基吡咯烷酮共混体系的相容性研究（Ⅰ）

 用ＤＳＣ，ＤＭＴＡ研究了醋酸纤维素（ＣＤＡ），聚乙烯基吮咯烷酮（ＰＶＰ）及ＣＤＡ／ＰＶＰ共混体系的玻璃化转变行为．用精密量热法测定了该体系的混合热焓．结果表明：共混体系只存在一个玻璃化转变温度（Ｔｇ），其值随共混组成的变化而改变；共混体系的混合热焓为负值，其绝对值随组成中ＰＶＰ含量的增加而减少．力学性能研究表明，共混体系具有协同效应．上述试验结果证明，ＣＤＡ和ＰＶＰ是一对相容性高聚物．     

纤维素/甲壳素共混膜的结构表征与抗凝血性能

以 6wt %NaOH 4wt%尿素为纤维素的新溶剂 ,采用溶液共混法制备出纤维素 甲壳素共混膜 ,为甲壳素在碱性溶液中制膜提供了新的方法 .红外光谱、X 射线衍射、扫描电镜和力学性能、抗凝血性能测试结果表明 ,共混膜中甲壳素含量低于 4 0wt%时 ,纤维素与甲壳素分子间具有良好的相容性 ;在纤维素中引入适量甲壳素可提高共混膜的抗张强度 ,共混膜的干、湿态抗张强度在甲壳素含量 10wt%时最大 ,其值分别为 89 1MPa和 4 3 7MPa ,比纯态纤维素膜的干、湿态抗张强度分别提高了 6 7%和 11 5 % ;甲壳素的引入可明显降低血小板在共混膜表面的粘附、凝聚与变性 ,增大共混膜的抗凝血参数 ,甲壳素含量达到 5 0wt%时 ,该共混膜具有良好的抗凝血性能     

再生纤维素／聚乙烯醇共混膜的研究

由纤维素铜氨溶液与不同体积比（１－１０％）的聚乙烯醇（ＰＶＡ）水溶液共混制备了一系列再生纤维素共混膜．扫描电镜结果表明ＰＶＡ含量大于８％时，该共混膜产生明显相分离．当ＰＶＡ低于５％时，共混膜相容性较好．膜的结晶度，抗张强度，直角撕裂强度，断裂伸长及耐热性均优于单独用钢氨液制备的再生纤维素膜．此外，用流动速率法和超滤法测定了膜的孔径，渗透性及纯水通量，结果表明共混膜的孔性没有明显变化．本文得出：再生纤维素与５％ＰＶＡ共混能改善力学性能，并且能保持其生物降解性．     

聚氧化乙烯-聚苯乙烯-聚氧化乙烯三嵌段共聚物/聚苯醚共混物的相容性和结晶行为

 本工作对聚氧化乙烯-聚苯乙烯-聚氧化乙烯(PEO-PS-PEO)三嵌段共聚物与聚苯醚(PPO)均聚物共混物的相容性及结晶行为进行了研究。结果表明,共混体系的相容性与嵌段共聚物中苯乙烯段的含量有关,PS含量越高,PPO与共聚物PS段的相容性越好。共混体系的结晶行为也明显不同于一般均聚物共混体系。在DSC降温结晶过程中最多可出现三个结晶峰。     

聚合物共混物的相容性及相分离

综述了聚合物共混物相容性和相分离的研究现状。介绍了聚合物共混物的相容性理论,影响相容性的因素及改善和相容性的方法和表征相容性的手段。聚合物共混物的相分离机理制约着材料的性能,旋节分离和成核－增长相分离分别形成不同的形态结构。旋节分离和成核－增长相分离所对应的动力学过程是不同的,散射光强与相分离时间分别满足指数和幂指数关系。     

苯乙烯－甲基丙烯酸共聚物和聚环氧丙烷共混体系的相容性研究

 本文用傅里叶交换红外光谱法（ＦＴＩＲ）表征了苯乙烯－甲基丙烯酸共聚物Ｐ（Ｓ－ＭＡＡ）和聚环氧丙烷（ＰＰｒＯ）共混体系的相容性．用谱带分离的技术比较准确地测定了共混体系中几种羰基的吸光系数比，并且用简明的方法定量计算了它们之间平衡的平衡常数．同时实验还表明共混组分中聚醚的分子量、分子结构、Ｐ（Ｓ－ＭＡＡ）中ＭＡＡ的含量以及共混组分的比例和体系的相容性有密切的关系．     

聚甲基丙烯酸甲酯与聚醋酸乙烯酯共混的红外光谱研究

用红外光谱(FTIR)研究了聚甲基丙烯酸甲酯(PMMA)与聚醋酸乙烯酯(PVAc)共混体系相容性,在160℃以上共混体系发生相分离;分相体系与非分相体系的FTIR谱明显不同;共混体系的FTIR谱不能从两统组分红外光谱简单加和得到;结果表明大分子构象发生了变化,PMMA/PVAc体系相容可能是大分子构象熵变所致。     

梳型聚醚-聚磺酸锂共混物的锂离子导电性

本工作合成了聚甲基丙烯酸齐聚氧化乙烯酯和聚甲基丙烯酸己磺酸锂两系列聚合物,研究共聚物结构对共混物的相容性和锂离子导电性的影响.结果表明,共混物的相容性是决定离子电导率的主要因素;共混物内锂离子传导发生在非晶区,聚合物的链段运动是离子传导的主要推动力.     

HQ-PPEK/PC共混物的相容性与流变性

聚芳醚酮;聚碳酸酯;共混物;流变性能;HQ-PPEK/PC共混物的相容性与流变性     

聚氧化乙烯-聚苯乙烯-聚氧化乙烯三嵌段共聚物/聚苯醚共混物的相容性和结晶行为

本工作对聚氧化乙烯-聚苯乙烯-聚氧化乙烯(PEO-PS-PEO)三嵌段共聚物与聚苯醚(PPO)均聚物共混物的相容性及结晶行为进行了研究。结果表明,共混体系的相容性与嵌段共聚物中苯乙烯段的含量有关,PS含量越高,PPO与共聚物PS段的相容性越好。共混体系的结晶行为也明显不同于一般均聚物共混体系。在DSC降温结晶过程中最多可出现三个结晶峰。     

PA-130/CA合金膜材料的研制及其性能

采用溶液共混和液-固相转变法(L-S)制备了用于高效液相色谱(HPLC)柱填料的共聚尼龙/醋酸纤维素共混物(PA-130/CA)。以小分子量化合物为探针分子,用HPLC数据表征了PA-130/CA合金膜材料的界面性能,并研究了其合金膜材料的相容性和热稳定性。结果表明:PA-130与CA有很好的相容性;该合金膜的热稳定性比纯CA膜的有所提高;质量比为30/70的PA-130/CA合金膜对不离解极性有机物的分离效率更高。     

聚乳酸/纳米SiO_2共混物的热性能

以两种含有不同功能团的纳米SiO2对聚左旋乳酸(PLLA)进行了共混改性,从而提高了PLLA的性能。在纳米SiO2的质量分数为0.5~5%范围内,PLLA与之是相容的,其中含有—NH2功能团的RNS型纳米对PLLA的Tg有一定的影响,加入质量分数为5%的RNS型纳米SiO2后,PLLA的Tg降至52℃。由于RNS纳米SiO2中的—NH2与PLLA分子链中的—C=O形成了弱的氢键,因此在相同质量分数下,对PLLA热稳定性的影响要高于含—CH3功能团的DNS纳米SiO2,质量分数为5%的纳米SiO2与PLLA共混后,PLLA/RNS纳米SiO2共混物的热失重起始温度为370℃,而PLLA/RNS纳米SiO2共混物的则为365℃。     

聚己内酯和乙基纤维素共混体系的环带球晶及液晶形态

聚己内酯（ＰＣＬ）中加入与其有一定混溶性的非晶组分乙基纤维素（ＥＣ）,可明显影响其长环带球晶的行为．表明具有低混溶性及某种分子间相互作用的二元共混体系ＰＣＬ／ＥＣ仍能在一定温度范围内形成环带球晶;良好的混溶性,强的分子间相互作用并非是二元共混体系中ＰＣＬ长环带球晶不可缺少的因素．通过偏光显微镜发现ＰＣＬ的加入有利于乙基纤维素／二氯乙酸溶液中液晶相的形成,用Ｆｌｏｒｙ关于棒状分子无规线团溶剂三元体系的理论对其进行了讨论．     

MISCIBILITY, THERMAL STABILITY AND RETENTION OF PVP FOR CROSSLINKED PVA/PVP BLENDS

The thermal behavior, miscibility, crystallite conformation and thermal stability ofcrosslinked(CL-) PVA/PVP blends were studied by DSC and TG methods, respectively. DSCresults showed that in the blend, the crystallinity,T_m and T_c of PVA were obviously lower thanthose of pure PVA; the crystal growth changed from three dimensional to two dimensional andonly a single T_g was detected. These facts demonstrated that this crystalline and amorphousblend have good miscibility. TG curves showed that providing the quantity of K_2S_2O_8 added ismore than 3 wt%,in the blends PVA will form a stable CL-network, whose thermal degradationtemperature was near to that of PVP. But crosslinking reaction will not take place for PVP. Theprocesses of thermal degradation of CL-blends are based on combining both the thermaldegradation of PVP and that of PVA crosslinked with corresponding quantity of K_2S_2O_8 CL-agent, respectively. The UV measurements showed that 75 wt% of PVP may be remained in CL-blend hydrogelscrosslinked by adding (3--5 wt% )K_2S_2O_8. This is mainly due to the stable CL-network formed and the good compatibility and properentanglement between the composites in the CL-blends.     

Compatibilization of polypropylene/poly(glycolic acid) blend with maleated poe/attapulgite hybrid compatibilizer: Evaluation of mechanical,thermal, rheological,and morphological characteristics

In this work, the compatibilization effects of hybrid maleated POE/attapulgite hybrid compatibilizer (M-POE/ATP) on the immiscible polypropylene/poly(glycolic acid) (PP/PGA) blends was investigated. The hybrid compatibilizer integrating strengthening, toughening and compatibilization functions was prepared via one-step reactive extrusion using peroxidated ATP as the initiator. Then, the effects of compatibilizer dosage on the mechanical, thermal, rheological and morphological characteristics of blends were evaluated in detail. It was found that the hybrid compatibilizer resulted in the significantly enhanced compatibility and mechanical performance. Increased amount of compatibilizer content fractionated and almost wholly suppressed the crystallization process of PGA. The compatibilized blends showed higher thermal stability than pure PGA, and lower storage modulus and complex viscosity at higher shearing frequency. PGA in the blends presented a much lower degradation rate, which lead to the higher strength retention of 81% for the blend with 4 wt% of compatibilizer in buffer solution after 35 days.     

Structure and properties of blend membranes prepared from cellulose and alginate in NaOH/urea aqueous solution

Regenerated cellulose (RC)/alginic acid (AL) blend membranes were satisfactorily prepared from 6 wt % NaOH/4 wt % urea aqueous solution by coagulating with 5 wt % CaCl₂ aqueous solution, and then treated with 3 wt % HCl. Morphology, crystallinity, mechanical properties, and thermal stability of the membranes were investigated by scanning electron microscopy (SEM), IR and UV spectroscopes, X‐ray diffraction, tensile tests, and thermogravimetric analysis (TGA). The RC/AL blends were miscible in all weight ratios of cellulose to alginate. The membranes have homogeneous mesh structures, and the mesh sizes of the blend membranes (200–2000 nm) significantly increased with increasing alginate content. The crystalline state of the AL membrane prepared from 6 wt % NaOH/4 wt % urea aqueous solution was broken completely, and the crystallinity of the blend membranes decreased with an increase of AL. Comparing with AL membranes, the tensile strength and breaking elongation of the blend membranes were obviously improved in dry and wet states. Therefore, the RC/AL blends offer a promising way of alginate as separate and functional materials used in the wet state. © 2001 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 451–458, 2001     

Miscibility and interfacial property studies of the blends of ethyl cellulose with copolyamide6/66/1010

Interfacial properties governing reverse osmosis separations were studied by using liquid chromatography data with respect to ethyl cellulose/copolyamide6/66/1010 (EC/PA-130) blends. The miscibility of ethyl cellulose/copolyamide6/66/1010 (EC/PA-130) blends was investigated by using differential scanning calorimetry (DSC) and Fourier transform infrared, while the interfacial properties of the blends, including the interfacial adsorption, hydrophobicity, polar and non-polar parameters and β-parameters, were studied by using liquid chromatography. The results show that EC and PA-130 are miscible at compositions of (80/20), (70/30) and (50/50). The hydrophobicity of EC/PA-130 increases with the of PA-130 content. The EC/PA-130(70/30) is superior to the other blends for separating non-dissociable polar organic solute and is more suitable for use as desalting membrane material. It seems that liquid chromatography is an effective tool for studying the interfacial properties of polymer blend materials and selecting high performance of membrane materials.     

Thermogravimetric analysis and differential scanning calorimetric studies on nanoclay-filled TPU/PP blends

Thermal stability of ester-thermoplastic polyurethane (TPU)/polypropylene (PP) and ether-TPU/PP blends was evaluated by thermogravimetric studies. Thermal studies were made as a function of blend ratio. Effects of compatibilization using MA-g-PP and nanoclay addition on thermal stability were evaluated. Mass loss at 400 °C was found to decrease with increasing PP content were determined. Finally the compatibility and crystallization behavior of the blends were studied by differential scanning calorimetry. Compared to the ether-TPU blend nanocomposites, the ester-TPU blends showed better compatibility and thermal stability.     

Blend films of natural wool and cellulose prepared from an ionic liquid

Natural wool/cellulose blends were prepared in an ionic liquid green solvent, 1-butyl-3-methylimidazolium chloride (BMIMCl) and the films were formed subsequently from the coagulated solutions. The wool/cellulose blend films show significant improvement in thermal stability compared to the coagulated wool and cellulose. Moreover, the blend films exhibited an increasing trend of tensile strength with increase in cellulose content in the blends which could be used for the development of wool-based materials with improved mechanical properties, and the elongations of the blends were considerably improved with respect to the coagulated films of wool and cellulose. It was found that there was hydrogen bonding interaction between hydroxyl groups of wool and cellulose in the coagulated wool/cellulose blends as determined by Fourier transform infrared (FTIR) spectroscopy. The ionic liquid was completely recycled with high yield and purity after the blend film was prepared. This work presents a green processing route for development of novel renewable blended materials from natural resource with improved properties.     

Cellulose acetate blends with acrylonitrile/N-phenyl maleimide copolymers morphological and thermal properties

Cellulose acetate (CA) was blended in different compositions with various acrylonitrile-N-halo phenyl maleimide (AN-XPhM) copolymers to improve the thermal and mechanical properties of cellulose acetate. The structure, morphology, thermal stability, and crystallinity of the blend films were characterized by infrared spectroscopy, scanning electron micrographs, thermogravimetry/differential thermal analysis, differential scanning calorimetry, and X-ray diffraction. The results revealed that the thermal stability was improved by the increase in AN-XPhM content, irrespective of the type of the N-halo phenyl maleimide. The CA/AN-4BrPhM blend films possessed the highest thermal stability compared to the other CA/AN-XPhM blend films. Blending CA with AN-4BrPhM yielded the most homogeneous blend films, irrespective of the composition ratio. The mechanical properties of various compositions of the CA/AN-4BrPhM blend films were also discussed.