聚醚醚酮与酚酞型聚芳醚酮的共混研究

借助DSC、FTIR、PLM(偏光显微镜)、SEM技术研究了聚醚醚酮(PEEK)/酚酞型聚芳醚酮(PEK-C)共混物的相容性特征及结晶行为、结晶形态。结果表明该共混物是部分相容的,其相容程度与共混物的组分比及热历史有关;共混物中PEK-C对PEEK的结晶有阻碍,其阻碍与共混物的组分比及结晶条件有关;共混物的结晶形态对共混组分比有较大的依赖,同时还与结晶温度有关。     

聚醚醚酮与酚酞型聚芳醚酮的共混研究EI

借助DSC、FTIR、PLM(偏光显微镜)、SEM技术研究了聚醚醚酮(PEEK)/酚酞型聚芳醚酮(PEK-C)共混物的相容性特征及结晶行为、结晶形态。结果表明该共混物是部分相容的,其相容程度与共混物的组分比及热历史有关;共混物中PEK-C对PEEK的结晶有阻碍,其阻碍与共混物的组分比及结晶条件有关;共混物的结晶形态对共混组分比有较大的依赖,同时还与结晶温度有关。     

乙炔端基砜和聚醚砜共混物的扭辫分析

用扭辫分析技术研究了双[4-(4-乙炔端基苯氧基)苯基)砜(ATS)和聚醚矾(PES)共混物及其不同条件下固化共混物的相容性及其动态力学行为。未固化共混物的相容性随ATS含量增加从相容体系转变为部分相容体系;在固化过程发生相分离,两相的玻璃化转变温度主要取决于固化条件。     

共聚物组成对PSMA／PSAN共混物相容性的影响

用浊点测定、傅里叶变换红外光谱和微差扫描热分析等方法研究了苯乙烯-顺丁烯二酸酐共聚物(PSMA)与苯乙烯-丙烯腈共聚物(PSAN)共混物的相容性。浊点测定的结果表明部分共混物加热产生相分离,呈LCST行为。从相容的共混物的红外光谱观察到丙烯腈—C≡N基团吸收带频率产生位移。研究结果表明当MA和AN含量差别不大时,PSMA/PSAN共混物相容。这是由于在一定的共聚物组成范围内,PSMA/PSAN共混物中存在较弱的特殊相互作用所致。     

PEN/PBT共混物的结晶行为和热性能

用差示扫描量热量仪(DSC)和热重分析仪(TGA)对聚对萘二甲酸乙二酯(PEN)/聚对苯二甲酸丁二酯(PBT)共混物的相容性、结晶行为和热性能进行了研究。结果表明,PEN/PBT共混物属于热力学相容体系。加入少量PBT会使PEN的冷结晶行为扩大。热稳定性相对较差的PBT的加入会在一定程度上使PEN/PBT共混物的热稳定性下降。     

PEK—C／PEEK共混物的研究

用挤出方法制备了新型聚芳醚酮(PEK-C)和聚醚醚酮(PEEK)共混物。对共混体系的相容性、转变、结晶结构及力学性能等进行了研究。初步结果显示了PEK-C和PEEK具有很好的互补和协同作用,表明该共混物是一种很有前途的工程材料。     

PC／PET共混物相容性和结晶行为的研究

本工作用差动扫描量热计(DSC)、动态粘弹仪(DMA)、密度梯度、激光小角散射仪(SALS)和光学解偏振仪研究了国产聚碳酸酯/聚对苯二甲酸乙二醇酯(PC/PET)共混物的相容性和结晶行为。DSC研究结果表明,共混物中在PET含量为60％以下时,只有一个玻璃化转变温度(T_g),说明共混物是完全相容的;在PET含量大于60％时,共混物呈现出两个玻璃化转变温度,并发生内移,说明共混物是部分相容的。用DMA测试也得到同一结果。共混物中PET的结晶动力学与一般结晶高聚物相似,等温结晶前期符合Avrami方程,等温结晶后期偏离Avrami方程。     

PES—C／PPS共混物结构与性能的研究

研究了聚芳醚砜(PES-C)/聚苯硫醚(PPS)共混物的聚集态结构与熔融流动性以及两者之间的内在关系。结果表明,PES-C/PPS共混体系属于多相体系,PES-C占50％时,PPS成为连续相,共混物在该组成比例下具有良好的熔融流动性。     

ATS／PEK—C共混物的相容性及其相分离

本文用动态力学扭辫分析(TBA)和扫描电镜(SEM)研究了乙炔端基砜(ATS)和酚酞型聚醚酮(PEK-C)共混物的相容性和相分离的行为特征.未固化ATS/PEK-C共混物为相容体系,ATS加入使PEK-C的Tg降低,共混物的Tg与ATS/PEK-C组成比有关.共混物在固化过程中发生相分离而形成两相结构,相分离程度与固化条件有关。     

聚醚砜与热致液晶共混物的相容性

用示差扫描量热器，动态粘弹谱仪和扫描电镜研究了热致液晶与聚醚砜的相容性，当液晶含量小于１０％时，共混物为相容体系，含量在１０％－２０％为部分相容体系，含量超过２０％为相分离体系。     

PEEK modified PLA shape memory blends: towards enhanced mechanical and deformation properties

Polylactic acid (PLA) is one of the most promising shape memory polymers with outstanding biocompatibility, while poly(ether ether ketone) (PEEK) is a special engineering plastic with excellent mechanical performance. In this work, PEEK was selected to modify PLA, and a series of PLA blended with different PEEK contents (PLA/PEEK blends) were obtained. The effects of PEEK on thermodynamic, mechanical and shape memory properties of PLA/PEEK blends were investigated. The results showed that the thermal stability of the PLA/PEEK blend was improved with the PEEK content increase. The tensile strength reached the highest value of 20.6 MPa when the PEEK content was 10%. While the best shape memory performance occurred with the PEEK content of 15%, the shape recovery time was less than 2 s, and the shape fixation/recovery ratio was more than 99%. Furthermore, the programmable mimetic flower opening process was achieved by using PLA/PEEK blends with different PEEK content ratios. The above results indicated that the blend of an appropriate proportion of PEEK had positive effects on mechanical and deformation performances of PLA.     

THERMAL TRANSITIONS AND MORPHOLOGICAL BEHAVIOR OF POLYETHER ETHER KETONE AND LIQUID CRYSTALLINE POLYMER BLENDS

Polyether ether ketone (PEEK) and thermotropic liquid crystalline polymer (TLCP) based on hydroxy benzoic acid and hydroxy naphthoic acid (HBA/HNA) were prepared on a single-screw extruder with rotor speed 45 rpm at 350°C. Thermal analysis data, especially the glass transition temperature (T_g), indicated that the blends were incompatible in the entire range of concentration. Melting temperature (T_m) of the blends was found to be close to melting temperature of pure PEEK. Thermogravimetric analysis data show the poor thermal stability of the blends compared to the parent material. The percent weight loss increased with increasing LCP concentration. Analysis with a scanning electron microscope clearly indicated that a distinctive fibrous morphology was developed in the extruded samples at the low concentration of LCP, but the adhesion of the fiber to the PEEK matrix was poor, with circular voids around the LCP phase at higher concentration.     

热塑性/热固性聚砜共混物的固化及其生成SIPN的热行为特征EI

用乙炔端基砜(ATS)与双酚A型聚砜(PSF)、聚醚砜(PES)、酚酞型聚醚砜(PES-C)制备了热塑性/热固性聚砜共混物及其半互穿聚合性网络(SIPN),并借助DSC技术对ATS及其共混物的固化反应和动态、恒温固化条件对生成SIPN的热行为特征进行了表征。     

Thin film and bulk deformation behaviour of poly(ether ether ketone)/poly(ether imide) blends

The deformation behaviour of amorphous thin films of poly(ether ether ketone) (PEEK)/poly(ether imide) (PEI) blends was investigated over a wide temperature range by optical and transmission electron microscopy. All the materials showed localized shear deformation at temperatures well below Tg. In pure PEI and in blends with up to 60 wt% PEEK content, a transition from shear deformation to disentanglement crazing occurred as the temperature was raised. However, this transition was absent in PEEK, which deformed by shear over the whole temperature range, and similar behaviour was found for PEI/80 wt% PEEK. It is argued that at high PEEK content disentanglement crazing is suppressed by strain-induced crystallization and some evidence for crystalline order in deformed regions of initially amorphous PEEK thin films was obtained by electron diffraction. The thin film deformation behaviour of the blends was also shown to be consistent with their bulk deformation behaviour, a high temperature ductile–brittle transition being observed at low PEEK content in tensile tests. This revised version was published online in November 2006 with corrections to the Cover Date.     

High-performance conductive materials based on the selective location of carbon black in poly(ether ether ketone)/polyimide matrix

A novel high performance conductive material with excellent comprehensive properties was prepared by melt-blending, and its performances were adjusted by controlling the selective location of carbon black (CB) in poly(ether ether ketone) (PEEK)/thermoplastic polyimide (TPI) matrix. With increasing the CB loadings, the morphology of PEEK/TPI blends changed from sea-island to co-continuous structure, which was owing to the selective location of CB in TPI phase. Notably, with the selective location of CB in the induced co-continuous PEEK/TPI matrix, the electrical percolation threshold was reduced to 5 wt%, which was significantly lower than that of binary PEEK/CB (9 wt%) and TPI/CB (10 wt%) composites. And the electrical conductivity of ternary PEEK/TPI/CB composites was 10⁴ to 10⁶ times higher than that of binary composites at identical 7.5 wt% CB loading, which was attributed to the double percolation effect. Moreover, the incorporation of CB could improve the thermal and mechanical properties effectively.     

PP/纳米SiO2粉体共混体系相容机理的研究

研究了偶联剂(KH-560)和偶联剂(KH-560)-增容剂(PP-g-MAH)的增容机理。采用扫描电镜观察纳米SiO2粉体在聚合物PP基体中的分散和界面作用来探讨纳米SiO2粉体与PP的相容机理。并建立了PP/纳米SiO2粉体共混体系的相容性机理的物理模型。     

聚醚醚酮及其共混物的研究EI

综述了高性能树脂聚醚醚酮及其共混物的研究现状，讨论了聚醚醚酮的形态结构、结晶和熔融双峰行为及力学性能的研究，指出了共混物的分子结构对相容性、形态结构及力学性能的影响，说明共混使所得高分子材料的性能更多样化。     

PPS／PBT共混体系的研究

在Ｂｒａｂｅｎｄｅｒ混合仪中，用熔融混合法制备结晶／结晶共混体系ＰＢＴ／ＰＰＳ。采用ＤＳＣ、ＷＡＸＤ和ＳＥＭ对共混物的结晶，熔融，相容性和形态进行了研究。结果表明，ＰＢＴ／ＰＰＳ共混物是不相容的，各自自己的微区内进行结晶。ＰＢＴ加入可使窝本粘度明显上升。     

Effect of carbon nanotubes on the mechanical properties and crystallization behavior of poly(ether ether ketone)

Pristine carbon nanotubes (CNTs) and noncovalently functionalized carbon nanotubes (f-CNTs) were used to prepare poly(ether ether ketone) (PEEK) composites (CNTs/PEEK and f-CNTs/PEEK) via melt blending. Noncovalently functionalized multiwalled nanotubes were synthesized using hydrogen-bonding interactions between sulfonic groups of sulfonated poly(ether ether ketone) (SPEEK) and carboxylic groups of nanotubes treated by acid (CNTs–COOH). The effects of these two kinds of nanotubes on the mechanical properties and crystallization behavior of PEEK were investigated. CNTs improved mechanical properties and promoted the crystallization rate of PEEK as a result of heterogeneous nucleation. Better enhancement of mechanical properties appeared in the f-CNTs/PEEK composites, which is ascribed to the good interaction between f-CNTs and PEEK. However, the strong interaction of f-CNTs and PEEK chains decreased the crystallization rate of PEEK for high content of f-CNTs.