CH_2CHCH_2Cl/MoO_2Cl_2/PPh_3引发丁二烯原子转移自由基聚合(英文)

以MoO2Cl2/PPh3为催化剂、CH2CHCH2Cl为引发剂,引发丁二烯进行原子转移自由基聚合,并用称量法、凝胶渗透色谱、核磁共振氢谱和傅里叶变换红外光谱对聚合产物的产率、相对分子质量及其分布和化学结构进行表征。结果表明,聚合产物的数均分子量与单体转化率呈线性增加关系,分子量分布较窄(1.4～1.6),聚合反应具有活性聚合特征,符合原子转移自由基聚合机理,所得聚丁二烯呈无规结构。     

Reverse atom transfer radical polymerization of styrene initiated with AIBN/Ni ( naph ) 2/PPh3 catalyst system

以AIBN/Ni(naph),/PPh3为均相引发剂引发苯乙烯聚合,所得试样相对分子质量与转化率呈线性增加,相对分子质量分布约为1.5.紫外光谱分析表明,聚合机理为反向原子转移自由基聚合.     

苄氯/MoCl3(OC8H17)2/PPh3引发丁二烯和苯乙烯的原子转移自由基共聚合

研究了以苄氯／MoCl3（OC8H17）2／PPh3,引发丁二烯和苯乙烯的原子转移自由基共聚合,所得聚合物的相对分子质量与转化率的增大呈线性增加,相对分子质量分布约2．0。紫外光谱分析表明,聚合机理符合原予转移自由基共聚合机理。差示扫描量热法分析表明,所得聚合物为无规共聚物。     

AIBN／Ni（naph）2／PPh3催化体系引发苯乙烯反向ATRP

以AIBN／Ni(naph)2／PPh3为均相引发剂引发苯乙烯聚合，所得试样相对分子质量与转化率呈线性增加，相对分子质量分布约为1．5。紫外光谱分析表明，聚合机理为反向原子转移自由基聚合。     

用偶氮二异丁腈/MoCl_3(OC_8H_(17))_2/三苯基膦催化苯乙烯-丁二烯反向原子转移自由基共聚合(英文)

以MoCl3(OC8H17)2/三苯基膦作为催化剂,用偶氮二异丁腈引发苯乙烯与丁二烯的反向原子转移自由基共聚合,分别通过称重法、凝胶渗透色谱分析及核磁共振分析对聚合物的产率、相对分子质量及其分布和结构进行了测定和表征。结果表明,所得聚合物的相对分子质量与单体转化率呈线性增加关系,相对分子质量分布较宽(多分散性指数为1.7～2.0),表明该反应具有活性特征。反应溶液的紫外可见光谱分析表明该聚合机理符合反向原子转移自由基共聚合机理。所得丁二烯-苯乙烯共聚物为无规共聚物。     

FeCl2/亚氨基二乙酸催化的原子转移自由基聚合制备苯乙烯/甲基丙烯酸甲酯嵌段共聚物

将催化剂FeCl2/亚氨基二乙酸用于原子转移自由基聚合制备PS-b-PMMA嵌段共聚物.大分子引发剂和嵌段共聚物的相对分子质量及其分布用GPC测定,共聚物的结构用红外光谱表征,玻璃化转变温度用DSC测定.     

丙烯酸酯原子转移自由基聚合多官能引发剂

分别用乙二醇和三羟甲基丙烷与二氯乙酰氯反应合成了双(二氯乙酸)乙二醇酯和三羟甲基丙烷三(二氯乙酸酯),通过测定它们与单官能团引发剂2-氯乙酸乙酯共同引发的丙烯酸酯原子转移自由基聚合所得聚合物的相对分子质量和相对分子质量分布,证明它们分别是丙烯酸酯原子转移自由基聚合的四官能团和六官能团引发剂.     

超高相对分子质量聚(甲基)丙烯酸酯的制备及应用

介绍了制备超高相对分子质量聚(甲基)丙烯酸酯的常用方法,如等离子体引发自由基聚合、单电子转移-衰减链转移自由基聚合、反向原子转移自由基聚合、可逆加成-断裂链转移聚合、高压原子转移自由基聚合、金属催化活性自由基聚合等,分析了单体含量、催化剂种类和用量、引发剂种类和含量、反应温度、反应时间、反应压力等对合成超高相对分子质量聚(甲基)丙烯酸酯的影响,介绍了其良好的机械强度和透光性能以及其应用情况。认为超高相对分子质量聚(甲基)丙烯酸甲酯其韧性不足,极大地限制了其适用范围,如果将其与纳米材料复合改性将可以弥补这个缺点。复合改性的超高相对分子质量聚(甲基)丙烯酸甲酯将在有机玻璃及包覆材料等领域中具有非常广泛的应用前景。     

三氯化苄/CuCl/Cu/2,2′-联吡啶引发的甲基丙烯酸甲酯原子转移自由基聚合(英文)

以三氯化苄为引发剂,对甲基丙烯酸甲酯的原子转移自由基聚合进行了研究。结果表明,在ＣｕＣｌ／２,２′－联吡啶催化下聚合速率很慢,加入铜粉可以大大提高聚合速率,所得聚合物的数均相对分子质量随单体转化率呈线性增加,相对分子质量分布指数小于１．３０,三氯化苄的引发效率约为０．７０。     

原子转移自由基聚合制备超支化聚合物进展

介绍了原子转移自由基聚合(ATRP)制备超支化聚合物的原理以及近年来采用ATRP方法制备的各种支化/超支化聚合物,展望了ATRP的发展趋势.ATRP是目前可控,活性聚合最成功的方法之一,它以过渡金属配合物为催化剂,通过有机卤化物引发乙烯基单体的自由基聚合,合成相对分子质量可控、相对分子质量分布窄的多种聚合物.     

ICAR ATRP of methyl methacrylate catalyzed by FeCl3·6H2O/succinic acid

In this work, methyl methacrylate (MMA) was polymerized by initiator for continuous activator regeneration (ICAR) atom transfer radical polymerization (ATRP) method to obtain low molecular weight living polymers. The ATRP initiator was ethyl 2‐bromoisobutyrate, the catalyst ligand complex system was FeCl₃·6H₂O/succinic acid, and the conventional radical initiator 2,2′‐azobisisobutyronitrile was used as a thermal radical initiator. Polymers with controlled molecular weight were obtained with ppm level of Fe catalyst complex at 90°C in N,N‐dimethylformamide. The polymer was characterized by nuclear magnetic resonance (NMR). The molecular weight and molecular weight distribution of the obtained poly (methyl methacrylate) were measured by gel permeation chromatography method. The kinetics results indicated that ICAR ATRP of MMA was a “living”/controlled polymerization, corresponding to a linear increase of molecular weights with the increasing of monomer conversion and a relatively narrow polydispersities index. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Photo‐Induced atom transfer radical polymerization with nanosized α‐Fe2O3 as photoinitiator

Photo‐induced atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) was achieved in poly(ethylene glycol)‐400 with nanosized α‐Fe₂O₃ as photoinitiator. Well‐defined poly(methyl methacrylate) (PMMA) was synthesized in conjunction with ethyl 2‐bromoisobutyrate (EBiB) as ATRP initiator and FeCl₃·6H₂O/Triphenylphosphine (PPh₃) as complex catalyst. The photo‐induced polymerization of MMA proceeded in a controlled/living fashion. The polymerization followed first‐order kinetics. The obtained PMMA had moderately controlled number‐average molecular weights in accordance with the theoretical number‐average molecular weights, as well as narrow molecular weight distributions (M_w/M_n). In addition, the polymerization could be well controlled by periodic light‐on–off processes. The resulting PMMA was characterized by ¹H nuclear magnetic resonance and gel permeation chromatography. The brominated PMMA was used further as macroinitiator in the chain‐extension with MMA to verify the living nature of photo‐induced ATRP of MMA. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42389.     

2-甲基-3-丁烯-2-醇合成3-甲基-2-丁烯-1-醇

[目的]2-甲基-3-丁烯-2-醇是异戊二烯间接皂化法生产3-甲基-2-丁烯-1-醇过程中产生的副产物,废物回收再利用是节能减排的有效措施.[方法]2-甲基-3-丁烯-2-醇经氯化、酯化和皂化得到3-甲基-2-丁烯-1-醇.[结果]结果表明:在优化条件下,氯化反应的产率可达87.25％,酯化和皂化反应的产率可达84.53％.[结论]该方法是2-甲基-3-丁烯-2-醇再利用的有效方法.     

Nd(opr~i)—AlR_3二元体系催化异戊二烯聚合活性

Nd(opr~1)Cl_2与AIR3组成的催化体系为一类新型异戊二烯定向聚合二元稀土催化剂。本文研究了该二元体系催化异戊二烯聚合的规律,结果表明,它能引发异戊二烯高顺式—1,4定向聚合,且其催化聚合活性受烷基铝的影响很大,AIEt3与Nd(opr~1)Cl_2组成的催化剂活性较高,而Al(i-Bu)_3活性很低,几乎不能引起聚合。     

Reverse atom‐transfer radical polymerization of acrylonitrile catalyzed by FeCl3/iminodiacetic acid

FeCl₃ coordinated by iminodiacetic acid (IMA) was Changed used for the first time as the catalyst in azobisisobutyronitrile‐initiated reverse atom‐transfer radical polymerization (ATRP) of acrylonitrile (AN). An FeCl₃ to IMA ratio of 1:2 not only gave the best control of molecular weight and its distribution but also provided a rather rapid reaction rate. The effects of solvents on the polymerization of AN were also investigated. The rate of the polymerization in N,N‐dimethylformamide (DMF) was faster than in propylene carbonate or toluene. The molecular weight of polyacrylonitrile agreed reasonably well with the theoretical molecular weight in DMF. The rate of polymerization increased with increasing polymerization temperature and the apparent activation energy was calculated to be 54.8 kJ mol⁻¹. The reverse ATRP of AN did not show obvious living characteristics with CuCl₂ instead of FeCl₃. Copyright © 2005 Society of Chemical Industry     

Preparation of vinyl polymers bearing photo‐labile diethylthiocarbamoylthiyl (S2CNEt2) groups via ATRP

Direct synthesis of vinyl polymers functionalized with photo‐labile diethylthiocarbamoylthiyl (S₂CNEt₂) groups was reviewed via three living polymerization procedures: normal atom‐transfer radical polymerization (ATRP), reverse ATRP and photo ATRP. The S₂CNEt₂ group was transferred by mediating the dormant–active species equilibrium in the course of polymerization and eventually ω‐terminating the resulting polymer chain. ATRP of methyl methacrylate (MMA) was successfully performed with a p‐toluenesulfonyl chloride/Cu(S₂CNEt₂)/2,2′‐bipyridine(bpy) or benzoyl peroxide (BPO)/Cu(S₂CNEt₂)/bpy initiation system. The oxidized complex, Cu(S₂CNEt₂)Cl/bpy, catalyzed the reverse ATRP of vinyl monomers initiated with BPO or 2,2′‐azobisisobutyronitrile (AIBN), producing tailor‐made polymers with ω‐S₂CNEt₂ groups and a narrow molecular‐weight distribution. Without external ligands, the living polymerization of vinyl monomers was achieved under the thermal initiation of diethyl 2,3‐dicyano‐2,3‐diphenylsuccinate (DCDPS) in conjunction with Fe(S₂CNEt₂)₃ catalyst. Photo ATRP of MMA and styrene was first realized in the presence of 2,2‐dimethoxy‐2‐phenylacetophenone (DMPA)/Fe(S₂CNEt₂)₃ under UV irradiation at ambient temperature. Copyright © 2004 Society of Chemical Industry     

ATRP of acrylonitrile catalyzed by FeCl2/succinic acid under microwave irradiation

A single‐pot atom‐transfer radical polymerization (ATRP) under microwave irradiation was first used to successfully synthesize polyacrylonitrile. This was achieved by using FeCl₂/succinic acid as the catalyst and 2‐chloropropionitrile as the initiator. Using the same experimental conditions, the apparent rate constant under microwave irradiation was found to be higher than that under conventional heating. The FeCl₂/succinic acid ratio of 1 : 2 not only gives the best control of molecular weight and its distribution but also provides rather rapid reaction rate. When FeCl₂ was replaced with CuCl, ATRP of AN does not show an obvious living characteristics. To demonstrate the active nature of the polymer chain end, the polymers were used as macroinitiators to proceed the chain‐extension polymerization. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1598–1601, 2006     

α‐Bis and α,ω‐tetrakis(4‐dimethylaminophenyl) functionalized polymers by atom transfer radical polymerization using 1,1‐bis[(4‐dimethylamino)phenyl]ethylene as tertiary diamine initiator precursor and functionalizing agent

The quantitative syntheses of α‐bis and α,ω‐tetrakis tertiary diamine functionalized polymers by atom transfer radical polymerization (ATRP) methods are described. A tertiary diamine functionalized 1,1‐diphenylethylene derivative, 1,1‐bis[(4‐dimethylamino)phenyl]ethylene (1), was evaluated as a unimolecular tertiary diamine functionalized initiator precursor as well as a functionalizing agent in ATRP reactions. The ATRP of styrene, initiated by a new tertiary diamine functionalized initiator adduct (2), affords the corresponding α‐bis(4‐dimethylaminophenyl) functionalized polystyrene (3). The tertiary diamine functionalized initiator adduct (2) was prepared in situ by the reaction of (1‐bromoethyl)benzene with 1,1‐bis[(4‐dimethylamino)phenyl]ethylene (1) in the presence of a copper (I) bromide/2,2′‐bipyridyl catalyst system. The ATRP of styrene proceeded via a controlled free radical polymerization process to afford quantitative yields of the corresponding α‐bis(4‐dimethylaminophenyl) functionalized polystyrene derivative (3) with predictable number‐average molecular weight (M_n) and narrow molecular weight distribution (M_w/M_n) in a high initiator efficiency reaction. The polymerization process was monitored by gas chromatography analysis. Quantitative yields of α,ω‐tetrakis(4‐dimethylaminophenyl) functionalized polystyrene (4) were obtained by a new post ATRP chain end modification reaction of α‐bis(4‐dimethylaminophenyl) functionalized polystyrene (3) with excess 1,1‐bis[(4‐dimethylamino)phenyl]ethylene (1). The tertiary diamine functionalized initiator precursor 1,1‐bis[(4‐dimethylamino)phenyl]ethylene (1) and the different tertiary amine functionalized polymers were characterized by chromatography, spectroscopy and non‐aqueous titration measurements. Copyright © 2012 Society of Chemical Industry     

均相Nd(Oct)_3/Al(i-Bu)_3/AlCl_3用于异戊二烯聚合

采用Nd(Oct)3、Al(i-Bu)3、AlCl3,AlCl3溶解于Al(i-Bu)3中配制成一定浓度的溶液作为氯配体。Nd(Oct)3与AlCl3在室温(20℃)下反应后,再加入一定量的Al(i-Bu)3,可配制成均相高效催化剂体系。所得聚合物同时具备顺-1,4含量高(96%)、高分子质量(105)、相对较窄的分子质量分布(Mw/Mn=2.1~3.0)等特征。更重要的是,证明了一些活性聚合的特征:a)无链终止反应;b)Mn和转化率线性相关;c)"种子"聚合中分子质量逐渐增加。虽然与典型的"种子"聚合有一些偏离,比如分子质量分布稍宽,Mn~转化率曲线不过原点,但仍然可认为是可控聚合。     

Synthesis and characterization of fluorescent perylene bisimide-containing glycopolymers for Escherichia coli conjugation and cell imaging

Fluorescent glycopolymers were prepared via combined atom transfer radical polymerization (ATRP) and ‘Click Chemistry’ in one-pot synthesis, in the presence of 2-azidoethyl methacrylate (AzEMA), 2-propynyl α-d-mannopyranoside, N,N′-bis{2-[2-[(2-bromo-2-methylpropanoyl)oxy]ethoxy]ethyl}perylene-3,4,9,10-tetracarboxylic acid bisimide (PBI-Br), copper (I) bromide catalyst and pentamethyldiethylenetriamine (PMDETA) ligand. Simultaneous ATRP and ‘Click Chemistry’ is an attractive method for the synthesis of functional glycopolymers as the reaction conditions are compatible with ATRP of an azide monomer, as long as an alkynyl-functionalized carbohydrate is available for click coupling reaction. The fluorescent glycopolymers were characterized by ¹H NMR, FT-IR, UV-visible absorption, fluorescence and X-ray photoelectron spectroscopies, as well as by gel permeation chromatography. Incubation of Escherichia coli (E. coli DH5α) with the fluorescent glycopolymers yielded green fluorescent bacterial clusters. The low cytotoxicity level of the fluorescent glycopolymers was revealed by incubation with 3T3 fibroblasts, macrophages and KB cells in 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays in vitro. Subsequently, the water-soluble, biocompatible and fluorescent glycopolymers were used as effective fluorescent cell labeling agents.