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1.
Amanda K. Pearce Jeffrey C. Foster Rachel K. O'Reilly 《Journal of polymer science. Part A, Polymer chemistry》2019,57(15):1621-1634
Entropy‐driven ROMP (ED‐ROMP) involves polymerization of olefin‐containing macrocyclic monomers under entropically favorable conditions. Macrocycles can be prepared from a variety of interesting molecules which, when polymerized, impart unique functionality to the resulting polymer backbone such as degradable linkages, biological moieties, crystallizable groups, or supramolecular hosts. In addition, the sequence of atoms in the cyclic monomer is preserved within the polymer repeating units, allowing for facile preparation of sequence‐defined polymers. In this review article, we consider how the mechanism of ROMP applies to ED polymerizations, how olefinic macrocycles are synthesized, and how polymerization conditions can be tuned to maximize conversion. Recent works in the past 10 years are highlighted, with emphasis on methods which can be employed to achieve fast polymerization kinetics and/or selective head‐to‐tail regiochemistry, thus improving polymerization control. ED‐ROMP, with its unique capability to produce polymers with well‐defined polymer backbone microstructure, represents an essential complement to other, well‐established, metathesis methodologies such as ROMP. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1621–1634 相似文献
2.
The ring-opening metathesis polymerization (ROMP) reaction is extraordinarily useful for the preparation of a large variety of polymers. We report that the length (n = 25-50) of high-substituent-density oligopeptide polymers synthesized by ROMP is dramatically improved upon addition of LiCl to reduce polymer and oligopeptide aggregation. This methodology should significantly expand the variety of polymers that may be prepared by ROMP and be of general use with norbornyl oligopeptides of any sequence. 相似文献
3.
Kang S Berkshire BM Xue Z Gupta M Layode C May PA Mayer MF 《Journal of the American Chemical Society》2008,130(46):15246-15247
A bis-phenanthroline [2]catenane copper complex, consisting of one olefinic macrocycle and one nonolefinic macrocycle, underwent an entropy-driven ring-opening olefin metathesis polymerization (ROMP) to provide a polypseudorotaxane. The polymerization featured an average degree of polymerization of ca. 63 wherein the polymer was effectively saturated with threaded macrocycles. Removal of the copper led to near complete release of the macrocycles from the polymer backbone. 相似文献
4.
综述了过渡金属均相催化的炔烃复分解反应进展,主要分为两部分:一是炔烃复分解反应在炔烃合成中的应用,即从六、七十年代Mortreux催化剂的发现能均相催化炔烃的歧化反应,经过一系列的条件改造,合成了炔醚和二芳基乙炔等化合物,并提出了可能的两种机理:金属卡宾和金属卡拜机理;金属钼和钨的卡拜络合物相继合成,发现此类络合物能够催化官能化的二炔的复分解反应,合成一系列的大环化合物。二是炔烃复分解反应在合成高聚物中的应用,即钙和钨的卡拜络合物被用来催化ROMP和ADIMET反应合成高聚物,改良了的Mortreux催化剂也能催化高聚物的生成,这些高聚物在发光器件、有机"塑料"激光、液晶显示器上都有应用。 相似文献
5.
环状聚合物具有不同于线性高分子的独特性质,是一类具有应用前景的新型聚合物材料,但复杂的结构导致其合成过程复杂繁琐."点击"化学由于其高效、可靠、高选择性的特点已成为拓扑高分子合成的新方法,活性自由基聚合(ATRP、RAFT和NMP)具有聚合物结构可控等特点,二者联用为环状聚合物的合成拓宽了思路.本文就近几年"点击"反应、"点击"反应与活性自由基聚合联用以及其他方法联用在环状聚合物中的应用进行综述."点击"反应与这些方法的结合将在功能性环状聚合物的设计与合成中发挥积极的作用. 相似文献
6.
Jinwoong Choi Hyunjoo Kim Taeyang Do Junsoo Moon Youngson Choe Jeung Gon Kim Joona Bang 《Journal of polymer science. Part A, Polymer chemistry》2019,57(6):726-737
Bottlebrush polymers (BBPs) are three‐dimensional polymers with great academic and industrial potential owing to their highly tunable and intricate architecture. The most popular method to synthesize BBPs is ring‐opening metathesis polymerization (ROMP) with Grubbs' catalyst, allowing living grafting‐through polymerization of macromonomers of up to ultrahigh molecular weights with narrow molecular weight distribution. In this case, it has been well recognized that the purity of macromonomers (MMs) is critical for a successful ROMP reaction. For MMs synthesized from reversible‐deactivation radical polymerization, Grubbs and Xia demonstrated that the better control of ROMP reaction can be achieved when they are prepared via “growth‐then‐coupling” method that is coupling a norbornenyl group to end‐functionalized prepolymers. However, these MMs can also contain various residual impurities from previous synthetic steps, which can potentially poison the catalyst and hamper the ROMP reaction. Herein, we intentionally doped possible impurities into purified MMs to identify the most poisoning species. As a result, it was found that alkyne‐functionalized norbornene most significantly retarded the ROMP reaction due to a formation of Ru‐vinyl‐carbene intermediates having low catalytic reactivity, whereas the other reagents such as solvent, Cu‐catalyst, ligands, and azido‐terminated prepolymers were relatively inert. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 726–737 相似文献
7.
Synthesis of cyclic polybutadiene via ring-opening metathesis polymerization: the importance of removing trace linear contaminants 总被引:1,自引:0,他引:1
The synthesis of cyclic polybutadienes using ring-opening metathesis polymerization (ROMP) was accomplished. A cyclic Ru alkylidene catalyst, where a terminal ligand was covalently linked to the Ru alkylidene, was used to polymerize either 1,5-cyclooctadiene (COD) or 1,5,9-trans-cis-trans-cyclododecatriene (CDT). Trace amounts of an acyclic impurity, 4-vinylcyclohexene, found in the COD led to samples which were contaminated with linear polymer. In contrast, CDT, which was free of the impurity, afforded pure cyclic polymer. These results provide a convenient method for discerning samples of pure cyclic polymer from those which contain trace to large amounts of linear polymer. Furthermore, they emphasize the need to use monomers that are free of acyclic impurities when preparing cyclic polymers using ROMP. 相似文献
8.
Pontrello JK Allen MJ Underbakke ES Kiessling LL 《Journal of the American Chemical Society》2005,127(42):14536-14537
We report a general method for the solid-phase synthesis of polymers via the ring-opening metathesis polymerization (ROMP). The method involves polymerization in solution to form a block copolymer, immobilization of the polymer via reaction of one block with a resin-bound functional group, modification of the other block, and liberation of the polymer from the resin. We demonstrated the utility of this approach by generating a block copolymer with an N-hydroxysuccinimidyl ester-substituted block (for on-resin functionalization) and a maleimide-substituted block (for conjugation to the resin). We showed that the Diels-Alder reaction can be employed to immobilize the polymers and that amines of diverse structure can be used to modify the resin-bound polymers. The reversibility of the furan-maleimide Diels-Alder adduct was exploited to liberate the polymer from the support. Specifically, treatment of the resin with cyclopentadiene resulted in complete polymer release. The resulting polymers are functional: they were as potent in assays with the lectin concanavalin A as polymers generated by traditional solution routes. We anticipate that this method can be used for the rapid synthesis of diverse polymers via ROMP. 相似文献
9.
Controlled preparation of brush polymers is important in the design of functional materials. In this study, poly(tert-butyl acrylate) macromonomers functionalized with norbornenyl end group(NB-PtBA) were synthesized via atom transfer radical polymerization in three different molecular weights, 2000(NB-PtBA-2k), 3000(NB-PtBA-3k), and 8000(NB-PtBA-8k). Additionally, brush polymers with PtBA as side chains were synthesized via ring-opening metathesis polymerization(ROMP). Kinetic studies on ROMP of NB-PtBA showed that there was a ceiling degree of polymerization(CDP) for the brush polymers, beyond which the polymerization of NB-PtBA was out of control. For brush polymers of P[NB-PtBA-2k] and P[NB-PtBA-3k], CDPs were estimated to be ca. 400, but the value of P[NB-PtBA-8k] was ca. 100. Therefore, the controlled ROMP of brush polymers was critical at the CDP limit with increased macromonomer molecular weight. 相似文献
10.
Influence of topology on the gelation behavior of coordination polymers prepared via ROMP of macrocyclic olefins
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Simone Albano Alessio Fantozzi José Augusto Berrocal Stefano Di Stefano 《Journal of polymer science. Part A, Polymer chemistry》2017,55(7):1237-1242
This work reports on the consequences of concatenation of two twin macrocycles on the gelation behavior of coordination polymers obtained via ring‐opening metathesis polymerization (ROMP) initiated by 2nd generation Grubbs' catalyst. The influence of concatenation is evaluated by comparison with the behavior of a non‐interlocked model complex under the same reaction conditions. The suitability of the choice of the non‐interlocked model complex is discussed in terms of molecular structure and effective molarity (EM). It is found that concatenation has a primary role in the gelation process, resulting in lower critical gelation concentrations for the endotopic, interlocked complex compared with the exotopic, non‐interlocked one. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 55, 1237–1242 相似文献
11.
[reaction: see text] Ring-opening metathesis polymerization (ROMP) of a photochromic 1, 2-bis(3-thienyl)cyclopentene monomer generated a series of novel polymers. All polymers exhibit reversible light-activated interconversion between their colorless-open and their colored-closed forms. 相似文献
12.
Franz Stelzer 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(7):941-952
Abstract Several transition metal alkylidene complexes are first discussed as catalysts for the ring-opening metathesis reaction. A new ruthenium catalyst with a slightly enhanced reaction rate is introduced. The stereochemistry and kinetics of the catalysts are investigated with different norbornene derivatives. Then it is shown that MgCl2 alone is a good heterogeneous catalyst for the ring-opening polymerization (ROMP) of norbornene compounds. This is the first catalyst which does not need activation by a transition metal compound or another organometallic cocatalyst. Applications of the ROMP reaction for the synthesis of polymer specialities covering conjugated liquid crystals and optically active polymers are shown. Poly(cyclopentadienylene vinylene) and sidechain liquid crystal polymers are discussed in more detail. Finally, the synthesis of liquid crystalline elastomers by incorporation of bifunctional monomers during the ROMP reaction is described. It is shown that this kind of polymer can be used for the fabrication of optically anisotropic materials. 相似文献
13.
Cyclic polymers have attracted more and more attentions in recent years because of their unique topological structures and characteristic properties in both solution and bulk state. There are relatively few reports on cyclic polymers, partly because of the more demanding synthetic procedures. In recent years, “click” reaction, especially Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC), has been widely utilized in the synthesis of cyclic polymer materials because of its high efficiency and low susceptibility to side reactions. In this review, we will focus on three aspects: (1) Constructions of monocyclic polymer using CuAAC “click” chemistry; (2) Formation of complex cyclic polymer topologies through CuAAC reactions; (3) Using CuAAC “click” reaction in the precise synthesis of molecularly defined macrocycles. We believe that the CuAAC click reaction is playing an important role in the design and synthesis of functional cyclic polymers. 相似文献
14.
《Journal of polymer science. Part A, Polymer chemistry》2018,56(6):645-652
This contribution describes our recent efforts geared toward the use of a general, thio‐bromo “click” reaction as a post‐polymerization method for the preparation of flame‐resistant polymeric materials. α‐bromo ester‐containing polymers could easily be prepared using ROMP and a subsequent, facile thio‐bromo click reaction was used for the installation of a phosphorus‐moiety that was shown to impart flame‐resistant/self‐extinguishing properties to these polymers. The extent of their flame resistance was then ascertained by treating paper (previously coated with polymer) to standard burn tests as well as measuring the limiting oxygen index (LOI). © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 645–652 相似文献
15.
Recent results for synthesis of end-functionalized polymers (EFP) by using olefin metathesis polymerization have been introduced including basic characteristics in ring-opening metathesis polymerization (ROMP) of cyclic olefins and acyclic diene metathesis (ADMET) polymerization for synthesis of conjugated polymers. Several approaches were demonstrated for synthesis of EFP by living ROMP using molybdenum (exclusive coupling with aldehyde) and ruthenium catalysts (sacrificial ROMP, chain transfer). Cis specific (Z selective) ROMPs were achieved by molybdenum, ruthenium, and vanadium catalysts by the ligand modification. The catalytic synthesis of EFP with high cis selectivity has been achieved by combined ROMP with chain transfer by V(CHSiMe3)(N-2,6-Cl2C6H3)[OC(CF3)3](PMe3)2. The ADMET polymerization using molybdenum and ruthenium catalysts afforded defect-free, high molecular weight poly(arylene vinylene)s containing all trans olefinic double bonds. The methods for precise synthesis of EFPs, exhibiting unique optical properties combined with the end groups, were developed. The catalytic one-pot syntheses for EFPs have also been developed. 相似文献
16.
Alkene metathesis is a superb methodology. We report the progress using alkene metathesis in the synthesis of polymeric organic semiconductors. Three classes of polymers have been synthesized using acyclic diene metathesis (ADMET) or ring opening metathesis polymerization (ROMP), viz., poly(acetylene)s (PA), poly(arylene‐vinylene)s (PAV), and organometallic polymers. For PAs, ROMP of cyclooctatetraenes is best, whereas for PAV, both ADMET and indirect and direct ROMP are viable. Metathesis performs flawlessly with the correct monomers, as molybdenum and particularly the robust Ru carbenes demonstrate. When performing ROMP, one is often rewarded with structurally uniform polymers that can display very low polydispersities. Overall, metathesis is a powerful tool for the preparation of semiconducting polymers. 相似文献
17.
《Journal of molecular catalysis. A, Chemical》2002,190(1-2):131-143
The reaction of norbornene (NBE) and norbornadiene (NBD) in the presence of seven-coordinate tungsten(II) and molybdenum(II) complexes of the [(CO)4M(μ-Cl)3M(SnCl3)(CO)3] and [MCl(M′Cl3)(CO)3(NCMe)2] (M=W, Mo; M′=Sn, Ge) types leads to ring-opening metathesis polymerization (ROMP) and to the formation of high molecular weight polymers. The geometric structure of these polymers was determined by means of 1H- and 13C-NMR spectroscopy. The monitoring of the reaction between cyclic olefins and the metal complex by means of 1H-NMR spectroscopy allowed us to observe the coordination of NBD to metal atoms in the initiation step of the polymerization process. Compounds of the [MCl(SnCl3)(CO)3(η4-NBD)] type prepared directly from [(CO)4M(μ-Cl)3M(SnCl3)(CO)3] or [MCl(M′Cl3)(CO)3(NCMe)2] (M=W, Mo) in the presence of an excess of NBD initiate the ROMP reaction immediately. The detection of the first-formed products in the reaction between the metal complex and cyclic olefins provides valuable information concerning the nature of the initiating species. 相似文献
18.
We present two novel allyl-based terminating agents that can be used to end-functionalize living polymer chains obtained by ring-opening metathesis polymerization (ROMP) using Grubbs' third generation catalyst. Both terminating agents can be easily synthesized and yield ROMP polymers with stable, storable activated ester groups at the chain-end. These end-functionalized ROMP polymers are attractive building blocks for advanced polymeric materials, especially in the biomedical field. Dye-labeling and surface-coupling of antimicrobially active polymers using these end-groups were demonstrated. 相似文献
19.
Synthesis and electrochemical properties of novel redox‐active polymers with anthraquinone moieties by Pd‐catalyzed cyclopolymerization of dienes
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Kenya Motokuni Bernard Häupler René Burges Martin D. Hager Ulrich S. Schubert 《Journal of polymer science. Part A, Polymer chemistry》2016,54(14):2184-2190
Redox‐active polymers enhanced the focus of attention in the field of battery research in recent years. Anthraquinone is one of the most generic redox‐active functional compounds for battery applications, because the quinonide structure undergoes a redox reaction involving two electrons and features stable electrochemical behavior. Although various redox‐active polymers have been developed, the polymer backbone is mostly based on linear alkyl chains [e.g., poly(methacrylate)s, poly(ether)s]. Polymers featuring ring structures in the backbone are limited due to the restricted availability of suitable polymerization techniques [e.g., poly(norbornene)s by ROMP]. The cyclopolymerization of dienes with pendant redox‐active anthraquinone moieties by Pd catalysis represents a novel approach to synthesize redox‐active polymers featuring cyclic structures in the backbone. Electrochemical investigations, in particular cyclic voltammetry, of these new diene monomer, polymers and the corresponding polymer supported carbon paper composites were conducted in different organic electrolytes. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2184–2190 相似文献
20.
The ruthenium-catalyzed ring-opening polymerization (ROMP) of 1-cyclobutenecarbonyl glycine methyl ester provides translationally invariant, head-to-tail ordered polymers. This polybutadiene backbone contains (within the limits of detection) only E-trisubstituted olefins, and it has no stereocenters that would serve as a source of structural ambiguities. Characterization of the polymer products indicates that they have polydispersities ranging from 1.2 to 1.6 and suggests that they are the products of a "living" polymerization. 1-Cyclobutenecarboxamide-derived ROMP polymers are excellent prospects for applications that require stereoregular chains functionalized with polar ligands. 相似文献