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芳香环状聚醚酮的合成是应现代高技术领域对先进复合材料的需求而发展起来的研究领域。综述了芳香环状聚醚酮的合成研究进展、合成方法,并分析各种合成方法的优势。 相似文献
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脂肪族环状碳酸酯的合成及其开环聚合研究进展 总被引:1,自引:0,他引:1
脂肪族聚碳酸酯是生物医用材料中的一个重要组成部分,而脂肪族环状碳酸酯开环聚合是制备脂肪族聚碳酸酯的一类重要方法。本文介绍了近年来不同大小和种类的脂肪族环状碳酸酯单体的合成及其聚合物的制备,并对其阳离子开环聚合、阴离子开环聚合和配位聚合的机理进行了讨论。 相似文献
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以2,2-二甲基-1,3-丙二醇和氯甲酸乙酯为原料合成了环状碳酸酯5,5-二甲基-1,3-二口恶烷-2-酮(DTC),并对DTC在食品添加剂乳酸锌引发下的微波开环聚合进行了研究.结果表明:在170 W的微波辐照下,辐照时间对聚合物的分子量有较大影响,当辐照时间为17 min时,聚合物的分子量达到最大,Mw、 Mn分别达到208 000和127 000. 相似文献
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以苯乙烯的ATRP聚合制备含卤端基的聚苯乙烯,再以此含卤端基的聚苯乙烯引发2-甲基-2-恶唑啉的正离子开环聚合,合成了苯乙烯与2-甲基-2-恶唑啉嵌段共聚物,并用IR,GPC对开环产物进行了表征。 相似文献
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从聚丁二酸丁二醇酯(PBS)的环状低聚物中分离提纯出了PBS的环状二聚物〔cyclic dimer of poly(butylenesuccinate),CDBS〕,采用核磁、质谱对该环状二聚物进行了表征,研究表明,通过分离纯化得到了纯度高的PBS的环状二聚物。以纯化的CDBS为原料、十二醇为初始剂、辛酸锡作催化剂,采用开环聚合的方法合成了PBS,采用核磁、红外光谱对合成的PBS的结构进行了表征,并研究了开环聚合温度、聚合时间以及催化剂用量对PBS的分子量、单体转化率的影响,结果表明,开环反应温度220℃左右,反应3 h,PBS的相对分子质量(简称分子量,下同)可达到63 300,与直接酯化-缩聚法相比,采用开环聚合法能提高PBS的制备效率。 相似文献
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Well‐crystal macrocyclic (arylene thioether ketone) oligomers were synthesized under high dilution condition by the reaction of Na2S with bis(4‐fluoro‐phenyl)‐methanone in 1‐methyl‐pyrrolidone (NMP). The oligomers were fully characterized by Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectra (MALDI‐TOF‐MS), high‐pressure liquid chromatography (HPLC), gel permeation chromatography (GPC), 1H NMR, 13C‐NMR, and differential scanning calorimetry (DSC). According to DSC studies, uncatalyzed and rapid ring‐opening polymerization (ROP) of the oligomers took place instantly when they were heated to melting point. Extracted by dichloro‐methane, the obtained polymer neither loses any weight nor dissolves in boiling 1‐chloro‐ naphthalene. These facts indicated that there are no residual oligomers within the resultant polymer. The as‐prepared oligomers could be potentially used as high‐temperature hot‐melt adhesive at a high temperature > 350°C, and matrices for high‐performance composites and nanocomposites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 161–166, 2006 相似文献
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The ROP of cyclic ethers, carbonates and esters in the presence of commercially available methylaluminoxane/trimethylaluminum system has been studied. MALDI-ToF end groups analysis indicates that in a majority of systems considered, the polymerization process is initiated by insertion of a monomer into the Al-O-Al bond, generating alkoxide species, which are active sites in coordination polymerization. The polymerization of six-membered carbonates proceeds selectively, forming linear polydiols with high yields at moderate temperatures. The polymerization of oxiranes and lactones is, however, accompanied by back-biting reactions leading to cyclic oligomers. The interaction of oxirane with aluminoxane electrophilic sites causes also the formation of cationic species, which initiate the polymerization of THF. The cationic species formed in those systems were trapped by triphenylphosphine and identified by 31P NMR spectra. 相似文献
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This paper describes the preparations and lithium-ion conductivities of various solid polymer electrolytes for potential use in high-energy density lithium-ion batteries. The ring opening polymerization of epoxides (M1–M6), catalyzed by Zn(II), Cu(II) and Cd(II) complexes in the presence of tetrabutylammonium bromide (TBAB), yielded polyethers (P1–P6) in which phosphates were attached as pendant groups. A reaction condition where Zn(II) catalyst used slightly excess to TBAB increased the polymerization rate remarkably and yielded the polyethers with higher molar masses in a short time. These polymerizations proceeded following a “monomer activated anionic ring opening polymerization” mechanism. These living like polymerizations also progressed according to “formation of polymer chain per initiator” model. The solid-state lithium-ion conductivities of these polymers were examined using lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). The conductivity of one of the solid polymer electrolytes with 40 wt% of LiTFSI was 5.2 × 10−5 S cm−1 at room temperature and 2.9 × 10−4 S cm−1 at 80 °C. 相似文献
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Ankit Vora 《Polymer》2009,50(13):2768-490
The synthesis of AB2-type miktoarm star polymers using a combination of reversible addition-fragmentation chain transfer (RAFT), ring opening polymerization (ROP) and “Click” chemistry was demonstrated in this work. An azide functional RAFT agent was used to polymerize butyl acrylate, polyethylene glycol acrylate and N-isopropylacrylamide monomers. Propargylamine was reacted with glycerine carbonate to obtain a dihydroxy functional alkyne compound which was used for the ring opening polymerization of ?-caprolactone (?-CL) and lactide. The resulting alkyne functional polycaprolactone (PCL) and polylactide (PLA) polymers were reacted with azide functional polymers in the presence of copper bromide (CuBr) catalyst to obtain miktoarm star polymers. The polymers were characterized by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. The star polymers had low polydispersity (∼1.3) with well-defined structures. These polymers have a number of potential applications including crosslinking agents for polyurethane (PU) coatings for biodegradable and fouling release applications. 相似文献
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Phosphonated polymers with a well-defined molecular weight, composition and architecture have been prepared via ring opening metathesis polymerization (ROMP) of phosphonated and non-phosphonated norbornene imides at room temperature for the first time. ROMP was proven to be living and versatile. This enabled preparation of a broad range of phosphonated homopolymers, statistical copolymers, AB diblock as well as ABA and BAB triblock copolymers based on poly(norbornene imide)s with low polydispersity (1.09–1.32). Complete hydrolysis of phosphonated poly(norbornene imide)s under mild conditions yielded the phosphonic acid derivatives. Thermogravimetric analysis indicated high thermal and thermo-oxidative stability of the polymers. Free standing and transparent films with good mechanical stability were obtained from the phosphonic acid functional homopolymers, diblock and triblock copolymers. Combining these basic properties with the advantages mentioned above makes ROMP a promising pathway for accessing a wide diversity of phosphonated macromolecular structures. These new phosphonated polymers will open new perspectives in advanced application areas, which require a high level of control over polymer structure. 相似文献
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Online monitoring of reaction temperature during cationic ring opening polymerization of epichlorohydrin in presence of BF3 and 1,4‐butanediol 下载免费PDF全文
This work introduces cationic ring opening polymerization of polyepichlorohydrin (PECH) produced under various reaction conditions (set temperature: ?10 to 40°C, [C]/[I] ratio: 0.1–1, monomer feed rate: 1–4 mL/min). In addition, a correlation between the exothermic reaction temperature and the performance of the PECH was obtained by utilizing a reaction temperature monitoring system, GPC, 1H‐NMR, and FTIR. During the polymerization, an induction period which affects the polydispersity was observed below 10°C. At lower temperatures and lower [C]/[I] ratios, a higher induction period was observed. The monomer feed rate did not affect the induction period but it highly affected the polydispersity when the induction period occurred. The total molecular weight of PECH increased with decreasing set temperature even though the amount of low molecular weight cyclic oligomer increased. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39912. 相似文献
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A series of macrocyclic(arylene multisulfide) oligomers were synthesized under high dilution conditions by reacting diphenyl ether/diphenyl/diphenyl disulfide/diphenyl methane with dichloro disulfide in the presence of a trace amount of iron powder by a one‐step reaction. From MALDI‐TOF mass spectra, it was established that the repeating units of the cyclization ranged from two to seven and the unit of macrocyclic(arylene multisulfide) oligomers had one to seven sulfur atoms. The macrocyclic oligomers readily underwent ring‐opening polymerization in the melt, resulting in linear, high molecular weight polymultisulfides. DSC thermograms demonstrated that the four polymultisulfides, derived from the macrocyclic(arylene multisulfide) oligomers, are amorphous in nature. The macrocyclic(arylene multisulfide) oligomers and polymers were analyzed by MALDI‐TOF‐MS, IR, HPLC, NMR, DSC, and TGA methods. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 735–741, 2004 相似文献
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Poly(dimethyl trimethylene carbonate) (PDTC) and poly(trimethylene carbonate) (PTMC) were synthesized by ring‐opening polymerization (ROP) of dimethly trimethylene carbonate (DTC) and trimethylene carbonate (TMC) in the presence of five kinds of natural amino acids (L ‐alanine, L ‐valine, L ‐leucine, L ‐proline, and L ‐phenylalanine). PDTCs with number‐average molecular weight (Mn) from 6700 to 18,900 g/mol and PTMCs with Mn from 7200 to 17,800 g/mol were obtained at a feed ratio of [monomer]/[L ‐phenylalanine] ranging from 50 to 200. The results of 1H nuclear magnetic resonance and titration proved amino acid connecting onto the polymer backbone. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献