聚醚酮酮和磺化聚醚酮酮物理性能的研究

研究了聚醚酮酮(PEKK)和磺化聚醚酮酮(SPEKK)的密度、吸水率、耐溶剂性能和电性能,用X—射线衍射研究了结晶度的大小,用差热分析、差示扫描量热分析和热失重法进行了热性能的研究,并对模压成型条件进行了探讨。与磺化聚醚酮酮相比,聚醚酮酮的密度略大,吸水率较小,耐溶剂性能好,结晶度大,熔点及热分解温度较高。     

特种工程塑料聚醚酮酮的性能

采用国产化聚醚酮酮(PEKK)原料,应用差示扫描量热法、热失重分析法、X射线衍射法、傅立叶变换红外光谱仪等手段对PEKK的耐热性、加工性能、力学性能进行了表征与测量。测试结果显示,PEKK是半结晶聚合物,加工温度范围在360~380℃,热稳定性很好,热分解温度在500℃以上。通过测试获得了较详实的数据,为国产PEKK的工业化应用提供了加工依据。     

高性能材料聚醚酮酮的生产、应用

介绍了高性能材料聚醚酮酮的性能,对亲核取代反应法、亲电取代反应法两种技术路线进行比较,并对聚醚酮酮的发展和应用进行综述。     

聚醚酮酮特性粘度的测定

考查了聚醚酮酮溶于浓硫酸中的时间与特性粘度的关系,探讨了通过不同特性粘度聚醚酮酮的共混来调节共混物特性粘度的方法。比较了用浓硫酸为溶剂时,采用单点法、外推法和算图法测定聚醚酮酮特性粘度时的优、缺点.结果认为算图法是一种快速、较准确的测定特性粘度的方法。     

新型耐高温杂环聚醚砜酮酮材料的研究

合成一种新型热塑性耐高温杂环聚醚砜酮酮材料（ＰＰＥＳＫＫ），研究了材料的热性能、力学性能、电性能、溶解性能、摩擦性能及膜性能。结果表明，ＰＰＥＳＫＫ为一类具有较高耐热性、综合性能优良、成本低的机械工程塑料。     

连续玻璃纤维增强聚醚砜和聚醚酮的力学性能研究

本文通过对制备的连续玻纤增强聚醚砜及聚醚酮这两种热塑性塑料的测试与分析，与连续玻纤增强热固性塑料进行了对比分析。     

高性能航天航空材料——聚醚酮酮

主要综述了聚醚酮酮(PEKK)的物理性能、合成方法和在航天航空领域的应用     

开展我国聚醚酮酮研究的建议

聚醚酮酮(PEKK)是继聚醚醚酮(PEEK)之后国外新开发的又一特殊结构型热塑性塑料。和PEEK比较,PEKK的玻璃化转变温度高10～12℃,拉伸模量高0.7GPa,断裂韧性虽低于PEEK,但和未增韧空间级环氧树脂比较则提高了10倍,用作碳纤维增强复合材料的基体树脂,具有很高的弯曲、剪切和压缩强度,而且对环境的适应性强,耐湿热性、耐燃性优良,有较高的极限氧指数,并具有较低的烟密度等。作者认为组织我国的技术力量,开发研究我国自己的这一具有上述引人注目特点的新型树脂——聚醚酮酮,以适应我国航空和宇航工业等高技术领域的需要,具有重要的意义。     

聚醚酮熔体过滤的研究

为了得到高纯度的聚醚酮产物,建立了一套新型聚醚酮挤出过滤装置对熔体进行过滤,研究了过滤的可行性,通过试验成功实现了聚醚酮产物的过滤,整个试验过程装置运行稳定,为聚醚酮过滤生产装置的研制和操作提供依据。     

聚醚酮酮的合成及性能研究

在温和条件下，以１，２－二氯乙烷为溶剂，无水三氯化铝为催化剂，二苯醚和对苯二甲醚为原料合成了高分子量的聚醚酮酮（ＰＥＫＫ）并找到了用浓盐酸脱除催化剂，乙醇提纯聚合物的有效途径，测试了ＰＥＫＫ的主要物理和化学性能，其中ＰＥＫＫ的特性粘度可达０．８－１．０，达到工程材料的要求。     

Thermal conductivity and diffusivity of carbon-reinforced polyetherketoneketone composites

Heat transfer properties play an important role in processing of polyetherketoneketone (PEKK)/carbon fiber (CF) composites. Accordingly, thermal conductivity and diffusivity of PEKK, PEKK/glassy carbon (GC), and PEKK/CF composites have been studied. Observed increase in conductivity and diffusivity with carbon filler addition was analyzed using the Maxwell–Eucken model. PEKK/GC composites with low carbon fraction indicated good fitting experimental points of the model, indicating good dispersion of particles. For PEKK/CF composites, the thermal conductivity and diffusivity increase is a reflection of a decrease in porosity. Results as observed from the model points to a homogenous dispersion within the PEKK/CF composites as well. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47975.     

Controlling Crystallization: A Key Factor during 3D Printing with the Advanced Semicrystalline Polymeric Materials PEEK,PEKK 6002, and PEKK 7002

Controlling the crystallization of advanced, high-performance polymeric materials during 3D printing is critical to ensure that the resulting structures have appropriate mechanical properties. In this work, two grades of polyetherketoneketone (PEKK 6002 and PEKK 7002) are used to print 3D specimens via a fused filament fabrication process. The samples are compared with polyetheretherketone printed under the same conditions. Two approaches for controlling the crystallization process are undertaken. The first involves adjustment of the chamber temperature between room temperature and 190 °C to create two regions where crystallization is governed by the slow diffusion process and elevated by limiting the nucleation process. The second approach involves selection of PEKK materials with varying crystallization kinetics, namely. Application of this method into 3D-printing process allows for printing semicrystalline materials with tailored mechanical, thermal, and chemical properties as either amorphous or in situ crystallized products. The studies undertaken here provide the basis to eliminate expensive and time-consuming post-processing of 3D fabricated parts. In particular, solutions for the avoidance of poor adhesion to the building plate and weak interlayer adhesion that can lead to warping are described. The materials are divided into three groups, slow, moderate, and too fast crystallization kinetics.     

The effect of titanium surface treatment on the interfacial strength of titanium – Thermoplastic composite joints

Co-consolidated titanium – carbon fibre reinforced thermoplastic composite hybrid joints show potential for application in aerospace structures. The strength of the interface between the titanium and the thermoplastic composite is crucial for the strength of the entire hybrid joint. Application of a surface treatment on the titanium is an effective way to improve this interfacial strength. This paper evaluates the effect of several titanium surface treatments on the interfacial strength between titanium and carbon fibre reinforced polyetheretherketone (PEEK) or polyetherketoneketone (PEKK). Furthermore, the underlying bonding mechanisms, activated by these surface treatments, are studied. The research result shows that the grit blasted titanium – carbon fibre reinforced PEKK interface outperforms the other interfaces.     

Preparation and properties of bisphenol A polyetherketoneketone based phthalonitrile resins

A promising high temperature phthalonitrile (PN) resin composed of a polyetherketoneketone (PEKK) core bridged by two bisphenol A linkers and end capped with PN groups is presented. This PEKK-PN resin was characterized via differential scanning calorimetry, thermogravimetric analysis, proton nuclear magnetic resonance spectroscopy, scanning electron microscopy, dynamic mechanical analysis, attenuated total reflection Fourier transform infrared, and rheometry. The PEKK-PN resin was evaluated with two different compositions containing 1) 70:30 PEKK-PN to bisphenol A PN (n = 0) and 2) pure PEKK-PN. The 70:30 PEKK-PN resin was mixed with bis[4-(3-aminophenoxy)phenyl]sulfone and exhibited a melt viscosity of 271 cP, much lower than the 657 cP viscosity of the pure PEKK-PN mixture. Void-free PEKK-PN polymers were easily prepared by degassing and curing up to 380°C, resulting in fully crosslinked networks exhibiting thermal stability above 500°C and a 75% char yield. Additionally, the cured PEKK-PN polymer samples displayed good mechanical integrity retaining 50% stiffness at 300°C. This combination of properties suggests these new PEKK-PN resins are excellent materials for high temperature thermosets in composite applications.     

Morphologies,Mechanical Properties and Wear of Poly(ether ketone ketone) (PEKK) and its Composites Reinforced with Mica

Poly(ether ketone ketone) (PEKK) composites were developed using mica as a filler. Sulfonated poly(ether ketone ketone) (S‐PEKK), a possible interfacial modifier, was coated on the mica surface with ca. 50 nm thickness, as observed by contact atomic force microscope (AFM). The morphologies of these materials were examined by scanning electron microscopy (SEM). In comparison with PEKK, significantly improved mechanical properties were obtained for the composite materials. With increasing content of mica in the materials, tensile modulus of the materials increased and ultimate elongation decreased. The composites containing 30 wt.‐% of mica exhibited a maximum tensile strength of about 200 MPa while pure PEKK showed a tensile strength of 102 MPa. The composites filled with mica treated by S‐PEKK displayed somewhat higher values of tensile strength and ultimate elongation than those generated using pure mica. The glass transition behavior and thermal stability of PEKK were not affected by the composition of the materials. The amount of mica used in the composites showed some influence on the coefficient of friction and wearing rate of these materials.     

Effect of PEKK oligomers sizing on the dynamic mechanical behavior of poly(ether ketone ketone)/carbon fiber composites

Poly(ether ketone ketone) (PEKK)/unidirectional carbon fiber (CF) composites have a poor interface. Accordingly, PEKK oligomer (PEKKo) sizing with a chemical compatibility with PEKK is proposed for promoting interfacial interactions in order to enhance mechanical performances. The thermal stability until 500 °C has been shown by thermogravimetric analysis (TGA). In order to compare static and dynamic sizing methods, “lab sizing” and “pilot sizing” were carried out. Scanning electron microscopy images of freeze fractures of PEKK/unsized CF, PEKK/PEKKo lab-sized CF and PEKK/PEKKo pilot-sized CF show that the PEKKo sizing causes an improvement of fiber/PEKK interactions, regardless of the sizing method. Indeed, in both cases, there is a continuity of matter at the interface while we observe a poor wetting of CF by matrix in PEKK/unsized CF. Dynamic mechanical relaxations in shear were analyzed as a function of temperature. The increase of storage modulus upon sizing is observed for both methods but it is more important for PEKKo pilot sizing. In the same way, the mechanical energy loss increases, it reflects the optimization of stress transfer between matrix and fibers. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48818.     

离心静电纺丝法制备聚醚酮酮纳米纤维

用离心静电纺丝方法,将国产化的高性能工程塑料聚醚酮酮(PEKK)制备成PEKK纳米纤维。对PEKK离心静电纺丝的可纺性、纺丝规律以及最终纤维的性能进行了研究。结果显示,离心静电纺丝能很好解决溶液浓度高、溶剂挥发困难的问题,PEKK的离心静电纺丝可纺性很好,溶液浓度的控制对于纤维形貌和直径影响明显,纺丝纤维的热性能比原材料有所降低。该研究为PEKK纳米纤维的制备开辟了新方向。     

High-temperature steam-treatment of PBI,PEEK, and PEKK polymers with H2O and D2O: A solid-state NMR study

Polyaryletherketones (PAEK) in blend systems with polybenzimidazoles (PBI) are of commercial interest due to their increased service temperature and reduction in abrasive wear against soft counterfaces when compared to PAEK alone. ASTM standard tensile specimens of PBI, polyetheretherketone (PEEK) and polyetherketoneketone (PEKK) are immersed in stirred D₂O at room temperature, and additional samples are contacted with D₂O steam at temperatures of 150 and 315 °C. All samples are studied by TGA, IR, ¹³C CP/MAS, ¹H wideline, and ²H MAS NMR. Changes in the physical appearance of the samples and the extent of D₂O uptake are described. Different locations, mobilities, and types of water and protons in the polymers are identified and studied and it is proven that PBI contains the largest amounts of D₂O after exposure under all conditions. PEEK and PEKK only incorporate minimal amounts of D₂O even when steam-treated at 315 °C.