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1.
PPEKK/PEI共混物的相容性及拉伸性能   总被引:3,自引:0,他引:3  
作为相容体系 ,聚芳醚酮与聚醚酰亚胺 (PEI)共混物体系的研究受到了研究者的重视[1~ 4] .由于现在已商品化的聚芳醚酮基本上都是半结晶型聚合物 ,所以有有关无定型聚芳醚酮与聚醚酰亚胺共混物的研究鲜见报道 .含二氮杂萘酮结构聚芳醚酮酮 (PPEKK)是一种新型耐高温聚合物 ,相比于已经商品化的各种聚芳醚酮 ,PPEKK除具有优异的综合性能外 ,它最大的特点表现在以下两方面 ,PPEKK耐热性突出 ,玻璃化转变温度 (Tg)为 2 4 5℃左右 ,远高于各种商品化的聚芳醚酮 ;PPEKK为无定型聚合物 ,易溶于多种有机极性溶剂 ,大大的扩…  相似文献   

2.
由自制的二甲基取代类双酚4-(3,5-二甲基-4-羟基苯基)-2,3-二氮杂萘-1-酮(DM-HPPZ)单体和4,4'-二氟二苯酮、4,4'-二氯二苯砜进行亲核缩聚反应,制备了一类新型的二甲基取代聚芳醚酮、聚芳醚砜及其共聚物聚芳醚砜酮树脂材料.在适宜的聚合条件下,获得了高分子量的聚合物,其特性粘度为0.44~0.75DL·g-1.利用DSC和TGA研究了聚合物的耐热性能,结果表明,新型聚芳醚玻璃化温度高(568~595K),耐热稳定性好(5%热失重温度大于416℃);拉伸强度为45.4~85.0MPa,力学性能优良.新型聚芳醚在氯仿、DMAc等极性有机溶剂中可溶解并浇铸得到透明、韧性高的薄膜.共聚物结合了聚醚酮好的力学性能和聚醚砜高的耐热性的特点,因此综合性能更佳.  相似文献   

3.
本文通过对聚芳醚酮亚胺和聚芳醚砜亚胺两类聚合物的裂解色谱质谱的解析,归纳出适合于正确鉴定这两类新型聚合物的表征化合物。  相似文献   

4.
利用双酚A型聚芳醚酮与联硼酸频哪醇酯在[Ir(COD)Cl]2和4,4'-二叔丁基-2,2'-联吡啶催化下反应,制备了新型含硼酸酯双酚A型聚芳醚酮,通过控制联硼酸频哪醇酯的投入量来实现硼酸酯的定量引入.再经过高碘酸钠作用得到含硼酸双酚A型聚芳醚酮,最后,通过高效Suzuki-Miyaura反应将偶氮定量引入到聚芳醚酮主链.利用核磁共振(1H NMR)确定了聚合物的结构,利用凝胶渗透色谱(GPC)确定了聚合物的分子量,利用差示扫描量热分析(DSC)和热失重分析(TGA)研究了聚合物的热性能,利用紫外-可见光谱(UVVis)研究了偶氮聚芳醚酮的光谱学性能.  相似文献   

5.
半结晶的聚芳醚酮类聚合物 ( PAEKs)因其性能优异而在机械、航天等高技术领域中得到广泛应用 .有关其晶体结构的研究亦有许多文献报道[1~ 11] ,而醚基与酮基在晶体结构方面是否等效一直存在争议 .虽然醚酮等效性的观点已被广泛接受 [4~ 8] ,但对于聚合物主链中含联苯基团的 PAEKs的醚酮等效性的研究则复杂得多 .文献 [1 ]报道醚酮等效性在主链含有联苯基团时不再成立 .本文首次发现醚酮等效性在主链含有联苯基团时在适当条件下仍可成立 ,并对聚芳醚酮类聚合物晶体结构的醚酮等效性问题进行了系统阐述 .1 实验部分  样品联苯聚醚酮 …  相似文献   

6.
聚芳醚酮树脂的分子设计与合成及性能   总被引:1,自引:0,他引:1  
聚芳醚酮树脂是20世纪发展起来的重要特种工程塑料.因其优良的耐热、耐腐蚀、耐摩擦及生物相容性好等特点,在国防军工、武器装备、航空航天、电子、汽车、机械、石油工业、核能及理疗卫生等高技术领有广泛的应用.此类材料大都采用双酚单体和双氟单体通过A2+B2型亲核缩聚反应制备.这类聚合物的分子结构对材料的性能影响较大,一般情况下分子链由醚、酮、苯三元规整结构构成时,聚合物为半结晶态;然而,当分子结构中存在侧基或其他非规整结构往往破坏聚合物的结晶结构,聚合物呈现无定型态.半结晶聚芳醚酮聚合物具有非常优异的耐热、耐化学稳定性一般作为结构型材料使用;无定型聚芳醚酮具有良好的加工性能,并且可进行一些功能化成为一类优异的功能型材料.本文从结构与性能关系出发,介绍了聚芳醚酮树脂种类,聚芳醚酮树脂的发展历程及合成方法;探讨了聚芳醚酮材料结构与性能关系;总结了功能性聚芳醚酮材料的前沿进展;最后结合实际展望了聚芳醚酮的应用发展方向.  相似文献   

7.
制备了新型可溶性含氟聚芳醚酮高性能材料, 使该材料结合了含氟聚合物与聚芳醚酮两种材料的优点, 既具有很好的热稳定性、溶解性和阻燃性, 又有较低的介电常数和吸湿性[5,9,10]. 对于提高聚芳醚酮类材料的性能, 拓展其使用范围和加工方法具有很大的开发前景和实用价值.  相似文献   

8.
以4,4'-二羟基苯基正戊酸和4,4'-二氟二苯酮为原料, 二甲基亚砜(DMSO)为溶剂, 采用亲核取代反应合成侧基含羧基的聚芳醚酮均聚物, 进一步与1-萘酚和2-萘酚接枝制备新型含萘可交联聚芳醚酮. 用核磁共振(NMR)、红外光谱(FTIR)、示差扫描量热(DSC)和热重分析(TGA)表征其结构和性能, 含萘聚芳醚酮在常用有机溶剂如N,N-二甲基乙酰胺(DMAc)、DMSO, 四氢呋喃(THF)中有良好的溶解性, 并具有很好的成膜性. DSC测试结果显示, 在170℃热处理2 h的交联聚合物的玻璃化转变温度(Tg)提高40℃. TGA数据显示接枝后的聚合物的5%热失重温度提高40~50℃, 证明其发生交联反应. 结果表明, 新型含萘可交联聚芳醚酮具有热固性树脂的耐溶剂和耐高温特性, 进一步拓宽了聚芳醚酮的应用前景.  相似文献   

9.
聚醚醚酮(PEEK)自八十年代初由英国ICI公司开发并工业化以来,由于其优异的性能已在机械、航天等领域得到广泛应用.但PEEK的Tg只有143℃,影响了使用范围.因此其它聚芳醚酮类聚合物相继被开发出来.但这些聚芳醚酮的主链结构大都为全对位连接,使其熔点较高以至加工难度增大.因此,高Tg和低Tm的聚芳醚酮的合成是一项很有意义的工作.如果在聚合物的主链结构中引入间位结构,则可在对Tg影响较小的情况下降低熔点来改善加工条件[1,2].新型间位聚醚酮醚酮酮(PEKEKK(T/I))也是其中一种.本文主要研究PEKEKK(T/I)的合…  相似文献   

10.
文章主要介绍了聚芳醚酮的合成路线与性质,讨论了对其改性的方向和进展,如共聚共混改性,在聚芳醚酮的主链中引入大的侧基破坏其规整性,以及研制含氟的新型聚合物。  相似文献   

11.
通过模型化合物ArOArCOArArCOArOAr(Ar为苯基或1,4-亚苯基)的全优化模型,得到芳环之间的平均二面角为37.5°,由其结构参数建立了刚性链聚芳醚酮(砜)类均聚物分子结构与其熔点及玻璃化温度的关系式,据此较好地了预测了新品种均聚物的热性能。  相似文献   

12.
The synthesis and characterization of new di‐ and tetra‐sulfonated ether diketone monomers are described. From these monomers, a wide series of sulfonated poly(arylene ether ketone)s (SPAEK) are synthesized by varying the sulfonic acid repartition along the polymer backbones. Their chemical structures are thoroughly characterized by NMR. From these polymers tough membranes are obtained from solution casting method and their water uptake, ionic conductivity, and water/gas permeation properties are determined and compared with those of Nafion membrane. Preliminary fuel cell tests show that SPAEK membranes are promising candidates for fuel cell application. This work brings new insights concerning the beneficial effects of introducing densely sulfonated monomers in a polyarylether macromolecular structure along with fluorinated groups improving conductivity while reducing unwanted excessive swelling. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 771–777  相似文献   

13.
Techniques for chloromethylation of polyarylether sulfones, poly-phenylene oxide, phenolic resin, and a model compound for the polyarylether sulfone are described. The rates of quaternization of chloromethylated polyarylether sulfone, I, and the corresponding model compound, II, with triethylamine, tri-n-butylamine, and quinuclidine in either DMSO or DMSO/dioxane are reported. Second-order kinetics are observed in the quaternization of II for the entire range of substitution. In contrast, quaternization of I followed second-order kinetics during the initial 35–60% of reaction only; higher degrees of quarternization occurred at reduced rates. After evaluating the potential impact of steric hindrance, added electrolyte, and initial extent of chloromethylation, the decrease in quaternization rate at high degrees of substitution is attributed to steric effects imposed by restricted rotation of the polymer chain. Comparable retardations are not observed during the quaternization of chloromethylated polystyrene under identical conditions.  相似文献   

14.
A new synthesis of DL-ar-turmerone starting from DL-curcumone is described.

The aromatic ketone DL-ar-turmerone (I) occurs with turmerone (II) a monocyclic sesquiterpene ketone, as chief component of the essential oil from the rhizomes of Curcuma longa Linn.  相似文献   


15.
Much effort has been dedicated to the molecular design and synthesis of model proteins to define protein folding interactions and to develop protein-based materials. Among them, the ring-opening polymerization of -amino acid-N-carboxyanhy- drides (NCAs) has drawn much attention because the resulting artificial polypeptides have wide applications in biotechnology, biomineralization and diagnostics1, 2. It is well known that dendrimers are hyperbranched macromolecules possessing a very high co…  相似文献   

16.
A new debenzylation of aromatic benzyl ethers by silica-supported sodium hydrogen sulfate is described. The process proceeds selectively and efficiently in good to excellent yields without affecting sensitive functional groups such as nitro, COOMe, aldehyde, ketone, and tosyl.  相似文献   

17.
A new AB(4)-type hypermonomer with four activated aromatic fluorines was prepared and converted to hyperbranched poly(ether ketones) by nucleophilic aromatic substitution of these fluorine atoms with phenolates. The preparation and application of the AB(4) hypermonomer for the accelerated synthesis of a family of poly(ether ketone) dendrons G2-G4 in good yield are described.  相似文献   

18.
A range of new C-4 heteroaromatic acromelic acid analogues has been synthesized in a parallel fashion from (-)-alpha-kainic acid 1. Protection of the amine and carboxylate groups of 1 followed by ozonolysis gave methyl ketone 8. A silyl enol ether 9, generated regiospecifically from the methyl ketone 8 using "kinetic" conditions, was brominated in situ with phenyltrimethylammonium perbromide to give the key alpha-bromo ketone 10. Parallel cyclization reactions of bromo ketone 10 with thioamides and thioureas were then performed. The aromatic heterocyclic derivatives 11a-d and 19 produced were deprotected to give the new kainoid amino acids 6a-d and 25 in excellent yield. Compounds 6a and 6c show strong binding to the kainate receptor. Reaction of 10 with alternative condensing agents was also briefly investigated.  相似文献   

19.
A highly selective and atom efficient ‘trifluoroacetic ester/ketone metathesis’ has been sincerely witnessed. Enolizable alkyl (at least two non-hydrogen atoms) aryl ketones were found to react readily with ethyl trifluoroacetate under the promotion of NaH to afford trifluoroacetic ester/ketone exchange products, trifluoromethyl ketones (TFMKs), and aromatic acid esters, which were quite different from the general Claisen condensation products, 1,3-diketones. The outcome of the reaction between ketone and ethyl trifluoroacetate is strongly related to the structures of substrates, the steric congestion caused by alkyl group is in favor of the C–C bond cleavage. DFT investigation further disclosed that the metathesis reaction was a kinetically favored pathway. Using only a slight excess of cheap trifluoromethylation reagent, simple operation and mild conditions make it a practical method for preparation of TFMKs on large scale, as well as a new choice of converting aryl alkyl ketones to aromatic acid esters.  相似文献   

20.
In the present paper, the ab initio molecular orbital method is employed to study the structures of the adducts of borane and aromatic ketone to chiral cyclic sulfur‐containing oxazaborolidine used as a catalyst in the enantioselective reduction of aromatic ketone. The catalyst–borane–ketone adducts have four different structures. All the structures are optimized completely by means of the Hartree–Fock method at 6‐31g* basis sets. The structure which is of the greatest advantage to a hydride transfer from the borane moiety to the carbonyl carbon of aromatic ketone is the one with the next lowest formation energy, and the plausible transition state for the hydride transfer is predicted to be of a twisted boat structure. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 78: 252–260, 2000  相似文献   

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