SYNTHESIS OF NOVEL BI-FUNCTIONAL COPOLYMER BEARING STERICALLY HINDERED PHENOL AND HINDERED AMINE GROUPS VIA RING-OPENING METATHESIS POLYMERIZATION

Norbornene derivatives exo,endo-2-[2-(3,5-di-tert-butyl-4-hydroxyphenoxy)-acetoxy]methyl-5-norbornene(M1) and 3,3,5,5-tetramethyl-4-piperidinyl 5-norbornene-exo,endo-2-carboxylate(M2)were synthesized and polymerized by RuCl_2(=CHPh)(PCy_3)_2 to prepare a novel kind of bi-functional polymer bearing sterically hindered phenol(SHP)and hindered amine(HLAS)groups via ring-opening metathesis polymerization(ROMP).The resulting copolymers were characterized by gel permeation chromatography(GPC),~1H-NMR and differen...

Synthesis,Structure,and Ring-opening Metathesis Polymerization of η~5-Pentamethylcyclopentadienyl-(η~5-exo-tricyclo [5.2.1.0^(2,6)]deca-2,5,8-trien-6-yl) Iron

η^5-Pentamethylcyclopentadienyl-（η^5-exo-tricyclo[5.2.1.0^2,6]deca-2,5,8-trien-6-yl） iron（3） was synthesized and characterized by ^1H NMR, ^13C NMR, MS, elemental analysis, IR, UV and X-ray diffraction analysis. Compound 3 was polymerized with ring-opening metathesis polymerization（ROMP） initiator （PCy3）2Cl2Ru=CHPh. ^1H NMR and IR spectra revealed the presence of CH=CH units in the polymer and supported the ROMP mechanism. GPC analysis of the polymer showed that the weight-average molecular weights（Mw） was 5967, and the polydispersity index（PDl） was 1.16. The polymer was also investigated by UV and cyclic voltammetry.

Synthesis of New Polymer Ionomers via Ring-Opening Metathesis Polymerization

The N-pentafluorophenyl-exo-endo-norbornene-5,6-dicarboximide (2a) and N-phenyl-exo-endo-nor-bornene-5,6-dicarboximide (2b) monomers were synthesized and polymerized via ring-opening metathesis polymerization (ROMP) using bis(tricyclohexylphosphine) benzylidene ruthenium(IV) dichloride (I) and tricyclohexylphosphine [1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene][benzylidene] ruthenium dichloride (II). Both catalysts were used to synthesize random and block high molecular weight copolymers which were further hydrogenated using a Wilkinson’s catalyst. Then, the saturated copolymers were modified by reacting with sodium 4-hydroxybenzene-sulfonate dihydrate to generate new ionomers with fluoro-sulfonic acid pendant groups.

RUTHENIUM CARBENE INITIATED RING-OPEN METATHESIS POLYMERIZATION OF ENDO-BICYCLO[3.2.0]HEPT-6-EN-3-YL BENZOATES WITH TACTICITY STUDIES

After tentative ring-opening cross metathesis （ROCM） of endo-bicyclo[3.2.0]hept-6-en-3-yl 4-bromobenzoate with PhCH = CH2 initiated by （Cy3P）2Cl2Ru = CHPh in CH2Cl2, ring-opening metathesis polymerization （ROMP） of a series of endo-bicyclo[3.2.0]hept-6-en-3-yl benzoates was achieved under the same conditions, furnishing a variety of the corresponding polymers. Then some of them were selected to hydrogenate the C=C double bonds in their backbone with p-tosylhydrazide, affording saturated and thus more flexible polymers. All of these polymers were well characterized by spectroscopic means including GPC, UV-Vis, NMR and IR, based on which the tacticity of these polymers was investigated together with nonlinear optical （electric-field-induced second-harmonic generation, EFISH）） analysis.

Synthesis of Cobalt Containing Block Copolymers Via Ring Opening Metathesis Polymerizastion (ROMP)

In order to realize a metal containing nano-structure, a block-copolymer containing alkynyl groups in one block was designed and synthesized by living ring opening metathesis polymerization (ROMP) technique. The newly developed bis-3-bromopyridine complex of Grubbs catalyst was employed in the series of polymerization and it yielded the desired polymers with great molecular weight control and narrow polydispersities. The characteristics of the block copolymers were investigated by gel permeation chromatography, H- and 13H- NMR spectroscopy. Complexation of the alkynyl group containing block copolymers by treatment with dicobalt octacarbonyl occurred smoothly in 5 min at room temperature. GPC analysis before and after cobalt complexation indicated a significant increase of the hydrodynamic volume. AFM images of the films before and after the complexation also showed a noticeable change in its morphology where grain sizes become smaller and more regular upon complexation.

(Arylimido)vanadium(V)-Alkylidene Complexes as Catalysts for Ring-opening Metathesis Polymerization(ROMP) of Cyclic Olefins: Ligand Design for Exhibiting the High Activity

(Imido)vanadium(V)-alkylidene complexes of type V(CHSiMe3)(NR)(OR?)(PMe3)2 [R = Ad, C6H5, 2,6-Me2C6H3, 2,6-Cl2C6H3;R?= 2,6-Me2C6H3, 2,6-i Pr2C6H3, 2,6-F2C6H3, C6F5, C6Cl5] exhibited from moderate to remarkable catalytic activities for ringopening metathesis polymerization(ROMP) of norbornene(NBE). The catalytic activities were affected by the ligand substituents, and V(CHSiMe3)(N-2,6-Cl2C6H3)(OC6X5)(PMe3)2(X = F, Cl) demonstrated the exceptionally high catalytic activities for ROMP of NBE.The complexes polymerized cycloheptene(CHPE) and cis-cyclooctene(COE), and ROMP of COE by the OC6 Cl5 analogue proceeded in a living manner even at 80℃, and the activity increased with increasing the temperature up to 120 ℃. Highly active catalysts for ROMP of cyclic olefins(NBE, cyclopentene, and CHPE) can be generated in situ by premixing isolated V(CHSiMe3)(NC6F5)(O-2,6-iPr2C6H3)(PMe3)2 with 1.0 equiv. of C6F5OH or C6Cl5OH via immediate phenoxy exchange;the activity was affected by the kind of phenol added [TOF in the ROMPs of NBE: 4.62 × 10^4 min^–1(upon addition of C6F5OH) versus 37.3 min^–1(none)].

From Polymerization Inhibition to Controlled Ring-Opening Metathesis Polymerization of Macromonomers with Tertiary Amine Groups:The Effect of Spacer Chain

Main observation and conclusion Ring-opening metathesis polymerization(ROMP)is a powerful toolbox in preparation of bottlebrush polymers for its high activity.However,the ROMP of macromonomers with repeating tertiary amine groups,for example,poly(2-(dimethylamino)ethyl methacrylate)(PDMAEMA).

Ring-opening Metathesis Polymerization of Cis-5-norbornene-endo-2,3-dicarboxylic Anhydride Derivatives Using the Grubbs Third Generation Catalyst

A series of cis-5-norbornene-endo-2,3-dicarboxylic anhydride （NDCA, M1） derivatives （M2-M4） with different types of nonpolar substituted groups were synthesized and characterized by 1H/13C-NMR and mass spectrometry （MS）. Ring- opening metathesis polymerization （ROMP） of these monomers using the Grubbs third generation catalyst （G3） generated high molecular weight polymers with much improved solubility compared with the NDCA＇s homopolymer. It was found that the solubility of these polymers increased with increased substituent＇s steric hindrance. The living polymerization of NDCA derivative containing the bulkiest substituent （M4） catalyzed by G3 in tetrahydrofuran was confirmed by the kinetic studies with low polydispersity indices （PDI） （〈 1.30）. By using sequential ROMP, well-defined diblock copolymers containing anhydride groups were synthesized.

Ring-opening metathesis polymerization of cyclopropene derivatives towards polyolefin elastomer analogues

Polyolefin elastomers(POEs) are important reprocessable industrial materials with high strain-recovery performance. Traditional POEs are prepared from transition-metal-catalyzed polymerization of ethylene and α-olefins, while because of the complicated coordination polymerization mechanism, defining the actual distribution and length of alkyl branches in POEs is extremely challenging. We herein propose an alternative approach of synthesizing POE analogues from ring-opening metathesis polymerization(ROMP) of highly strained 3,3-alkyl-substituted cyclopropenes(CPEs). The structures of monomers and the substituents of Ru-catalysts are investigated in detail to evaluate the homobenzyl-substituted CPE derivative as a new living ROMP monomer. After copolymerization with cyclooctene and backbone hydrogenation, POE analogues with well-defined alkyl branches are prepared. Since the ROMP reactions have little isomerization and can also give good control of molecular weight and copolymer composition, it is hypothesized that this synthetic approach provides a novel platform to assist understanding the influence of branches on the properties of POEs.

Polymerization of Dicyclopentadiene by Reaction Injection Molding

Dicyclopentadiene was polymerized by reaction injection molding (RIM) using a catalyst system based on molybdenum (V) chloride and anhydrous aluminum chloride and triethylaluminum. The effect of the reaction temperature on the polymer network and the type of the polymerization were discussed.

可化学降解类聚烯烃材料的制备及性能研究

聚烯烃(主要是聚乙烯和聚丙烯)是应用最为广泛的高分子材料之一,但其广泛的使用也带来了日益严重的环境污染,为人类生存和地球生态圈带来了前所未有的挑战。通过开环易位聚合(ROMP)的方法合成“类聚烯烃”,合成步骤简单,在控制聚合物组成、分子量和分散性等方面具有显著优势,可以通过引入极性官能团合成对环境友好、绿色的可降解“类聚烯烃”材料。以二醇和十一烯酰氯为原料,合成了3种双烯酯类单体,在GrubbsⅡ催化剂的作用下分别与环辛烯(COE)、二聚环戊二烯(DCPD)生成热塑型和热固型2种类聚烯烃,并进行了结构表征和性能测试。研究结果表明,所合成的类聚烯烃材料的力学性能良好且可化学降解。

eROP结合ROMP合成嵌段聚合物PCL-b-PB-b-PCL

采用新型化学酶法——开环易位聚合反应(ROMP)与酶促开环聚合反应(eROP)联用合成嵌段聚合物PCL-b-PB-b-PCL,用核磁共振氢谱(1 H NMR)、凝胶渗透色谱(GPC)和差示扫描量热法(DSC)表征产物的结构并进行性能测试.结果表明:GPC数据向高分子量移动,即成功合成了嵌段聚合物;嵌段聚合物可完全水解,且GPC数据向低分子量移动,表明该方法可行、有效.

Synthesis of Polynorbornene-Poly(ethylene-co-propylene)Diblock Copolymer

Transformation of living ring-opening metathesis polymerization into coordination polymerization by converting the titanacyclobutane group attached to a polynorbornene chain into titanocene alkoxide has been used for the synthesis of polynorbornene-poly(ethylene-co-propylene) block copolymer. Preliminary characterizations of the copolymerization products by solvent extraction and C-13 NMR spectrum are reported.

Ceiling Degree of Polymerization for Brush Polymers Prepared via ROMP of Poly（tert-Butyl Acrylate） Macromonomers

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.

两亲性ABA三嵌段共聚物的合成及其自组装行为研究

用Grubbs第二代催化剂引发降冰片烯类单体(NBEDE)和链转移剂在离子液体[bmim][BF4]中的开环易位聚合(ROMP)反应,反应体系保持均相,无聚合物析出,得到两端为叔溴的遥爪型官能化聚合物(Br-PNBEDE-Br).以Br-PNBEDE-Br作为大分子引发剂,在离子液体介质中引发甲基丙烯酸2-(二甲氨基)乙酯(DMAEMA)的原子转移自由基聚合(ATRP),制得分子量分布较窄的两亲性三嵌段共聚物(PDMAEMA-PNBEDE-PDMAEMA).利用动态激光光散射(DLS),原子力显微镜(AFM),透射电镜(TEM)等技术,考察嵌段共聚物在选择性溶剂/共溶剂(H2O/THF)中的胶束行为,以及溶液pH值对胶束的影响.结果表明,TEM观察到胶束为球形,由于TEM和AFM是在干态下测得胶束的粒径,而DLS是在溶液中测定胶束的流体力学直径,所以TEM和AFM得到的胶束粒径小于DLS的结果.不同pH值对胶束尺寸大小有明显的影响,胶束微粒随着pH值的增大而增大.

含吡啶配体的钌催化剂合成及在离子液体中开环易位聚合反应

合成了离子液体负载的钌催化剂,考察了该催化剂在离子液体中对极性环烯烃单体的开环易位聚合(ROMP)反应规律.首先设计合成含离子液体的吡啶配体1,2-二甲基-3-己氧基吡啶六氟磷酸盐咪唑离子液体配体,利用其与Grubbs第二代催化剂配位反应,制备离子液体负载的钌催化剂,通过1H,13CNMR等方法对合成的化合物和催化剂进行表征.催化剂中与钌连接的苯亚甲基上氢(RuCH—Ph)的振动峰由原来Grubbs第二代催化剂的δ19.2移至δ18.6,表明得到了新的催化剂,ICP测定催化剂混合物中纯催化剂的质量分数为36.2%.该催化剂易溶于丙酮、甲醇及咪唑类离子液体等极性溶剂,解决了Grubbs催化剂不溶于离子液体的问题,实现了在纯离子液体中均相ROMP反应.考察了催化剂对极性单体5-羟基环辛烯在离子液体[BMIm]BF4中的ROMP反应规律,研究了离子液体中ROMP反应动力学.

含咪唑离子盐的环辛烯在离子液体中开环易位聚合微观研究

用核磁共振方法研究了带电荷的环辛烯单体在离子液体和CDCl3中开环易位聚合反应的微观特征，根据单体在化学位移δ=5．66～5．58处双键氢积分峰面积的减少和聚合物主链上不饱和双键氢移至高场δ=5．38～5．39处峰面积积分的增加来表征聚合反应的情况．检测和记录了单体在有离子液体参与的条件下均相聚合反应和在CDCl3中的异相聚合反应过程，根据在不同反应体系中Grubbs第二代崔化剂中与Ru相连的苯亚甲基上氢在核磁图谱上δ=19．2处的峰型变化，探讨在两种介质中的不同聚合行为．研究表明，该单体在离子液体介质中的均相聚合有可控聚合的微观特点，并通过ln[M]0/[M]与反应时间的关系曲线，证实了反应的活性特征．

双环戊二烯催化开环移位聚合研究进展

环烯的开环移位聚合已经成为高分子工程领域的一个研究热点。其中,双环戊二烯由于具有来源方便、价格低廉,聚合后力学性能优异等优点而成为开环移位聚合热点研究对象之一。许多过渡金属化合物都可以作为双环戊二烯开环移位聚合的催化剂,通过采用不同的催化体系,可以得到不同结构的聚合物。介绍了双环戊二烯移位聚合反应机理及催化体系的研究进展。

降冰片烯及其衍生物开环易位聚合的研究进展

环烯烃开环易位聚合(ROMP)是指在金属催化剂存在下,环烯烃中的碳碳双键断裂并重新结合形成新的分子,得到的聚合物中留有不饱和双键,具有活性聚合的特点。ROMP是改造碳碳双键最有效的手段之一,极具特色且广泛应用于高分子材料与有机分子的合成。关于环烯烃ROMP研究早在20世纪50年代就已开始,当时的研究主要集中在以Ti、Re、W、Mo等过渡金属配合物组成的Ziegler-Natta催化体系引发环烯烃ROMP。20世纪80年代中期以后,研究则以亚烷基类或卡宾型类催化剂为主,其引发环烯烃ROMP的机理更加清晰。随着结构明确、稳定高效的环烯烃ROMP催化剂的开发与完善,该领域的研究焦点开始转向环烯烃ROMP适用单体的拓展以及所得聚合物的应用。在环烯烃ROMP研究中,降冰片烯及其衍生物是研究最多和应用最广的一类单体,这是因为它们的反应活性较高,来源丰富,价格也不昂贵。除研究拓展ROMP适用单体外,研究者主要从降冰片烯基单体的空间位阻、化学构型、侧基极性以及与其他环烯烃或降冰片烯基单体共聚改性等方面不断进行尝试,同时充分发挥环烯烃ROMP优势,与其他聚合方法联用,不断改善所得聚合物的性能并将其应用于不同研究领域。降冰片烯及其衍生物ROMP在阻燃材料、交换膜、纳米材料、生物医药等领域已取得一系列研究成果,其中在阻燃材料领域研究最早且许多产品已经工业化。在交换膜领域,由于降冰片烯基聚合物膜的热稳定性、耐酸碱性和电导率均较好,目前的研究主要是探索如何在燃料电池中获得应用。纳米材料是近年来最热门的研究领域之一,降冰片烯基纳米金属聚合物材料和纳米磁性聚合物材料等已有初步应用。在生物医药领域,降冰片烯及其衍生物极具发展前景,目前的研究主要集中在药物传输材料,已有初步的研究成果,但要实现工业化尚待进一步研究。此外,基于降冰片烯及其衍生物的接枝聚合物、嵌段聚合物、液晶聚合物、导电聚合物等也获得人们越来越多的关注。本文简要介绍了降冰片烯及其衍生物ROMP的反应机理,以及ROMP催化剂从多组分到钼、钨系再到钌系等几个发展阶段,详细综述了降冰片烯及其衍生物ROMP在上述若干领域的研究进展,并在此基础上简要探讨了今后研究与开发应用的新方向。

Synthesis of Single-stranded Polynorbornene with Pendant Group Bearing Benzenedicarboxaldehyde and Long Alkyl Chain

An unprecedented single-stranded polynorbornene with the pendant group containing benzenedicarboxaldehyde and a long alkyl chain（12） was synthesized by ring-open metathesis polymerization（ROMP） of the corresponding monomer（11）,which was obtained via the esterification of two crucial intermediates,namely,2-hexadecyloxy-5-hydroxymethyl-1,3-benzenedicarboxaldehyde（7,obtained via 6 steps） and 4-（4-aza-tricyclo[5.2.1.0 2.6 ]-dec-8en-4-yl）benzoic acid（10）.The target compound and all the intermediates were characterized by infrared（IR）,1 H NMR and high resolution mass spectroscopy（HRMS） analysis.