原子转移自由基聚合(ATRP)在星形聚合物合成中的应用

综述了近10 年来采用原子转移自由基聚合(ATRP) 法合成星形聚合物的研究进展。从聚合单体、引发剂、聚合方法和反应条件以及聚合物性质等方面讨论了原子转移自由基聚合在星形聚合物合成中的应用,并根据聚合方法和引发剂对各种反应进行了分类。对原子转移自由基聚合技术在合成功能性复杂星形聚合物中的应用进行了展望。     

非线形嵌段共聚物的合成

主要介绍了非线形嵌段共聚物,如星型嵌段共聚物、杂臂星型共聚物、梳型聚合物等的合成方法,包括多官能团引发剂法、大分子引发剂法等。各种活性聚合方法,如阳离子开环聚合、原子转移自由基聚合(ATRP)和氮氧稳定自由基聚合等都可以用于合成非线形嵌段共聚物。     

开环歧化聚合——高分子结构设计与裁制的一种极其有用的工具

在纵观近年来国际上关于开环歧化聚合（ROMP）反应研究成果的基础上，木文旨在指出这一聚合反应已成为高分子结构设计与裁制的一种极其有用的工具。     

卟啉四臂星型聚乳酸的制备与表征

利用本体聚合方法,采用辛酸亚锡为催化剂,四氨基苯基卟啉为引发剂,引发丙交酯开环聚合,制备四臂星型聚乳酸功能高分子材料.采用1 H-NMR,FTIR,GPC等对星型聚合物的分子结构、分子量及其分布等进行了研究.利用溶液浇铸成膜方法,制备了聚乳酸薄膜材料;并利用XRD方法,研究了聚乳酸薄膜的结构.研究表明,利用四氨基苯基卟啉为引发剂,合成了以卟啉为核的四臂星型聚合物,其溶液浇铸薄膜具有正交晶系α晶型结构,而线型聚乳酸呈非晶态结构.利用紫外可见吸收光谱研究了星型聚乳酸的光谱性质,结果表明合成聚合物具有锡卟啉的光学特性.     

星型三杂臂共聚物的合成及其自组装性能研究

通过将点击化学,原子转移自由基聚合与阳离子开环聚合相结合,合成了一种含亲水性聚乙二醇(PEG),疏水性聚四氢呋喃(PTHF)和环境响应性聚甲基丙烯酸N,N-二甲氨基乙酯(PDMA)的ABC星型杂臂聚合物MPEG-PTHF(-PDMA).通过FTIR、1H-NMR和凝胶渗透色谱/多角度激光光散射联用(SEC/MALLS)对其结构进行了表征.通过激光粒度仪和透射电子显微镜测试,并研究其在溶液中的自组装行为,分别在pH为5.0、7.4和9.5的缓冲溶液中测试了这种星型三元共聚物自组装性能,其可表现出温度响应性.     

烯烃易位聚合研究新进展 在合成嵌段共聚物及功能高分子上的应用

本文详述了利用环烯烃开环易位聚合合成，ＡＢ，ＡＢＡ和星形嵌段共聚物，接枝共聚物，氧化还原性聚合物，侧链液晶高分子，导电高分子及含金属纳米聚合物材料，并对其具体合成线路作了概述。     

含偶氮苯侧基接枝共聚物的可控合成及其光响应性能研究

以引发单体为基础,通过两种可控聚合方法,即原子转移自由基聚合(ATRP)和开环易位聚合(ROMP)的联用,合成一种新型侧链含偶氮苯基团的接枝聚合物刷.含叔溴的降冰片烯引发剂首先引发偶氮苯单体的ATRP反应,生成聚合物接枝链,每条接枝链上都带有偶氮苯基团;然后,将具有高环张力降冰片烯的ATRP聚合物作为大分子单体,在第三代Grubbs催化剂的引发下进行ROMP反应,生成结构明确的新型接枝共聚物.其主链每个单体单元上均含有一条带偶氮苯基团的接枝链.最后,研究此类接枝共聚物在紫外与可见光照射下的光响应性能,并用UV-Vis分光光度计研究其在溶液中的顺反异构化过程.     

原子转移自由基法合成八臂星型聚苯乙烯

设计合成了星型聚合物引发剂四(2,2-二氯乙酸)季戊四醇酯(TDCAP), 并通过原子转移自由基聚合合成了八臂星型聚苯乙烯. 用FTIR, 1H NMR和GPC等手段对引发剂和星型高分子的结构进行了表征.     

7-氧杂降冰片烯的官能化及其开环易位聚合

设计合成了含氧化乙烯重复单元和咪唑盐侧基的降冰片烯类单体,用Grubbs催化剂(PCy3)2Ru(CHPh)Cl2(1)和(SIMes)(PCy3)Ru(CHPh)Cl2(2)对单体进行了开环易位聚合(ROMP).考察了单体在不同条件下(溶剂、温度等)的聚合反应,尤其是在离子液体中ROMP的聚合特征.结果表明,2的催化活性比1的高;2催化单体在有机溶剂中聚合所得聚合物的分子量不可控,而在离子液体[BMIm]PF6中能够顺利进行均相聚合反应,且对聚合物的分子量可控性较好.用核磁共振谱(NMR)对合成的单体及聚合物的结构进行了表征.用差示扫描量热法(DSC)测定聚合物的玻璃化转变温度为-17.34℃,采用循环伏安法测得聚合物的电化学稳定窗口为3.0V.     

多力响应基团聚合物合成的研究进展

多力响应基团聚合物(MMPs)的设计与合成为高灵敏地观察和定量力化学转变及高效利用机械能提供了新机遇,推动了聚合物力化学的发展.本文主要介绍了后聚合改性、逐步聚合、开环易位聚合和活性/可控自由基聚合等4种MMPs的合成方法,分别对这些方法的特点、优势和适用体系进行了论述,期望为新型机械力响应性聚合物的制备和应用提供新思路.     

A convenient synthesis of high-loaded palladium(II) ROMP polymers

Bis[1-(5-norbornen-2-yl)butan-1,3-dionato]palladium(II) was conveniently prepared from 5-acetoacetyl-2-norbornene and sodium tetrachloropalladate. The former could be subjected to ROMP to give a highly-loaded palladium(II) ROMP polymer with a palladium loading of 23% by weight.     

Xanthene dye functionalized norbornenes for the use in ring opening metathesis polymerization

A convenient synthetic route towards polymerizable fluorescein, dicholorofluorescein, and eosin dyes is presented. Polymerizability was provided by linking 2‐norbornene carboxylic acid, 11‐bromo‐undecyl ester to the dye's carboxylate functionality. Although the monomers bearing dichlorofluorescein and eosin were obtained in high yield, the related fluorescein bearing monomer could only be obtained in low yield. In the latter case, concurring etherification and esterification led to a product mixture of the desired carboxy modified monomer and a double substituted by‐product. The dye‐monomers were used successfully for the preparation of statistical copolymers with endo,exo‐2,3‐norbornene dicarboxylic acid dimethylester by ROMP. Absorption and luminescence characteristics and, in particular, the acid/base sensitive behavior of the parent dyes were preserved in the monomers and copolymers. The absorption and emission maxima in THF solution and in the solid state were red shifted in comparison to the aqueous samples of the parent dyes. Dye‐copolymers exhibited good film forming properties. Solid state luminescence studies of the copolymers revealed an increasing sensitivity towards NEt₃ vapor in the order fluorescein < dichlorofluorescein < eosin bearing copolymer. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1336–1348, 2007     

Synthesis of reactive poly(norbornene): Ring‐opening metathesis polymerization of norbornene monomer bearing cyclic dithiocarbonate moiety

A norbornene monomer bearing cyclic dithiocarbonate moiety (NB‐DTC) was successfully synthesized from the corresponding precursor having epoxy moiety by its reaction with carbon disulfide. NB‐DTC underwent the ring‐opening metathesis polymerization (ROMP) catalyzed by a ruthenium carbene complex to give the corresponding poly(norbornene). The dithiocarbonate moiety incorporated into the side chain of the obtained poly(norbornene) reacted with amine to afford the corresponding thiourethane moiety with thiol group, which underwent oxidative S‐S coupling and/or addition reaction to the C‐C double bond in the main chain, leading to formation of a cross‐linked polymer. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011.     

1,1-(1-Propene-1,3-diyl)-ferrocene: modified synthesis, crystal structure, and polymerisation behaviour

The dehydro[3](1,1^′)ferrocenophanes, 1,1^′-(1-propene-1,3-diyl)-ferrocene (3a), and 1,1^′-(3-phenyl-1-propene-1,3-diyl)-ferrocene (3b) were synthesised under Shapiro conditions from the tosylhydrazones of the corresponding α-oxo-[3](1,1^′)ferrocenophanes. Electrochemistry shows 3a is oxidised at smilar potential to ferrocene; according 3a can be chemically oxidised using silver trifluoromethanesulfonate. The structure of 3a shows a ring tilt of 11.3°. Attempts to polymerise 3a using the ROMP initiator Mo(CHCMe₂Ph)[N(2,6-ⁱPr₂C₆H₃)][OCMe(CF₃)₂]₂ led to a mixture of insoluble material and a soluble mixture of apparently cyclic oligomers ([3a]_n).     

Novel doubly polymerizable functional norbornene: Its synthesis,reactivity, and macromolecular architectures from a dual cure via ring‐opening metathesis polymerization and radical photopolymerization

A novel doubly polymerizable functional norbornene, 5‐(methacryloyloxyethylamino carboxylmethyl)bicyclo[2.2.1]hept‐2‐ene (NBMOACM), was prepared. The ring‐opening metathesis polymerization (ROMP) of NBMOACM was carried out to prepare polymers with crosslinkable side chains with the Grubbs catalyst. No gel formation occurred during the ROMP of NBMOACM. The ¹H NMR spectrum of poly(NBMOACM) showed broad signals between 5.10 and 5.40 ppm, corresponding to the vinyl protons of the cis and trans double bonds of the ring‐opened polymer. Increasing the ratio of the monomer concentration to the catalyst concentration resulted in the formation of higher molecular weight polymers. Poly(NBMOACM) was incorporated into poly(methyl methacrylate) [poly(MMA)] to produce AB crosslinked materials. These crosslinked materials [1 wt % poly(NBMOACM), 10% weight loss temperature = 300 °C in air] had higher thermal stability than pure poly(MMA) (10% weight loss temperature = 276 °C in air). © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6287–6298, 2006     

Novel active ester‐bridged copolynorbornene materials containing terminal functional hydroxyl,amino, methacryloyl,or ammonium groups via ring‐opening metathesis polymerization

Several random and block copolynorbornenes with side chains containing terminal hydroxyl, amino, methacryloyl or ammonium groups were derived from the functional alkyl ester‐containing norbornenes by ring‐opening metathesis polymerization (ROMP). The main chain of ROMP‐type polynorbornene had a more important role for glass‐transition temperature in comparison with vinyl addition polymerization. There is little effect on glass‐transition temperature (about ?39 °C) of polynorbornenes with different length of alkyl side chain. The organosoluble copolynorbornenes with active crosslinkable methylacryloyl side chains derived from functional hydroxyl group were prepared to improve the thermal stability of poly(methyl methacrylate) [decomposition temperature (T_d)^10% = 325 °C in nitrogen] by forming networked AB crosslinked polymer (T = 367 °C in nitrogen). The sizes of nanometer‐scale polymeric micelles of block copolymers having hydrophobic alkyl ester and hydrophilic ammonium groups were measured in the range of 11–25 nm by scanning electron microscopy. These polymeric materials with various functional groups or amphiphilic architectures are accessible by ROMP, whose topology makes them particularly attractive for application potential such as biomedical and photoelectric materials. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4233–4247, 2005     

Cure characterization and viscosity development of ring-opening metathesis polymerized resins

The ring-opening metathesis polymerization (ROMP) kinetics of three different norbornene-based monomers, ethylidene norbornene (ENB), endo-dicyclopentadiene (DCPD) and exo-DCPD, in the presence of Grubbs’ catalyst are examined using differential scanning calorimetry and rheokinetic viscosity measurements. Several different parameters were considered, such as, the monomer healing agents (including different monomer mixtures), the catalyst concentration, and test temperature to determine how these parameters influence cure development. The polymerization kinetics, quantified by exothermic peak locations in the case of differential scanning calorimetry and rheokinetic transition times in the case of viscosity measurements, are shown to be highly dependent on monomer type and catalyst concentration. The ENB monomer had the fastest kinetics even at the lowest catalyst concentration compared to the other diene monomers and mixtures.     

Preparation of Hydroquinone‐Containing Polymers by ROMP

Polymers containing ortho‐ and para‐hydroquinone moieties 5a,b and 6a are prepared in good yields by ROMP from hydroquinone‐fused norbornadiene derivatives 1a,b and 2a . Oxidation of 5b yielded a quinone derivative 7 , which is evidenced by a strong absorption at 1656 cm^?1 in infrared spectrum.