原子转移自由基聚合进展及其在新型聚合物制备中的应用

概述了原子转移自由基聚合(ATRP)的机理及其在引发体系、单体、反应温度和介质等方面的进展;着重论述了ATRP在进行聚合物分子设计,制备具有特定结构的聚合物,如无规、梯度和交替共聚物,嵌段共聚物,末端官能团聚合物,接枝和梳状聚合物,星型高支化聚合物等方面的应用。     

原子转移自由基聚合进展

综述了原子转移自由基聚合(ATRP)的发展：引发剂、过渡金属络合物的发展,低温下的反应可节省能源,水分散体系的ATRP也是发展的方向ATRP可合成结构清晰的嵌段、接枝、星型、超支化高聚物,大大拓宽了高聚物的应用范围。     

原子转移自由基聚合研究进展

综述了原子转移自由基聚合的研究进展。     

原子转移自由基聚合法合成星形聚合物

将偶联技术应用于原子转移自由基聚合领域合成了星形聚苯乙烯、星形聚丙烯酸甲酯、星形聚苯乙烯聚丙烯酸丁酯嵌段聚合物,其中星形聚苯乙烯臂数可达２８。     

原子转移自由基聚合制备生物材料的研究进展

原子转移自由基聚合(ATRP)在制备生物材料方面起着非常关键的作用,很多分散度低、结构规整、分子量可控的聚合物材料被制备并广泛应用于生物材料领域。基于ATRP技术,人们制备了各种各样的药物传输、基因传递、可降解聚合物、防污表面、医疗成像、抗菌表面、聚合物-蛋白杂合物等生物材料。     

原子转移自由基聚合在聚合物分子设计中的应用

原子转移自由基聚合反应 ( ATRP)是一种新的活性自由基聚合方法 ,自 1995年提出后 ,引起高分子合成化学及工业界的关注。本文详细介绍了 ATRP在端功能基聚合物、大分子单体、嵌段共聚物、接枝共聚物、星形聚合物、梯度共聚物、超支化聚合物等聚合物分子设计中的应用     

原子转移自由基聚合研究进展及其在聚合物制备中的应用

概述了原子转移自由基聚合(ATRP)的机理及其在引发体系、单体等方面的进展。论述了ATRP反应在进行聚合物分子设计,制备具有特定结构的聚合物,如梯度共聚物,嵌段共聚物,末端官能团聚合物,接枝聚合物,星型超支化聚合物,响应型聚合物等方面的应用。     

原子转移自由基聚合研究进展

原子转移自由基聚合(ATRP)反应是实现活性聚合的一种颇为有效的途径,可以合成分子量可控、分子量分布窄的各种聚合物.介绍了ATRP的研究进展,包括ATRP反应的特点、聚合反应机理、应用、研究现状及前景展望.     

原子转移自由基聚合最新研究进展

概述了原子转移自由基聚合（ATRP）在引发体系、反应温度、反应介质、实施方法等方面的进展；介绍了3种不同催化剂脱除技术；结合最新的研究成果，着重论述了ATRP在进行聚合物分子设计，制备窄分子量分布聚合物、无规、梯度和交替共聚物，嵌段共聚物，末端官能团聚合物，接枝和梳状聚合物，星型及高支化聚合物等方面的应用。     

原子转移自由基聚合在树形聚合物合成中的应用

原子转移自由基聚合(ATRP)技术是一种新型的可控/活性聚合技术,可有效地对聚合物的分子结构进行设计,制备出各种不同性能、不同组成、不同功能化的结构确定的聚合物。综述了利用ATRP技术合成树枝状-线性嵌段共聚物、类树枝状聚合物(dendrimer-like polymer)、具有刺激-响应性末端基团的树枝状聚合物、树枝状-星型嵌段共聚物和基于树枝状聚合物的聚合物刷的研究进展。     

Preparation of hyperbranched polymers by atom transfer radical polymerization

A cheap acrylic AB* monomer, 2‐(2‐chloroacetyloxy)‐isopropyl acrylate (CAIPA), was prepared from 2‐hydroxyisopropyl acrylate with chloroacetyl chloride in the presence of triethylamine. The self‐condensing vinyl polymerization by atom transfer radical polymerization (ATRP), a “living”/controlled radical polymerization, has yielded hyperbranched polymers. All the polymerization products were characterized by proton nuclear magnetic resonance spectroscopy (¹H NMR). CAIPA exhibited distinctive polymerization behavior that is similar to a classical step‐growth polymerization in the relationship of molecular weight to polymerization time, especially during the initial stage of the polymerization. However, a significant amount of monomer remained present throughout the polymerization, which is consistent with typical chain polymerization. Also, if a much longer polymerization time was used, the polymer became gel. As a result of the unequal reactivity of group A* and B*, the polymerization is different from an ideal self‐condensing vinyl polymerization: the branch structures of polymers prepared depend dramatically on the ratio of 2,2'‐bipyridyl to CAIPA. Hyperbranched polymers exhibit improved solubility in organic solvent, however, they have lower thermal stability than their linear analogs. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2114–2123, 2002     

Synthesis and characterization of hyperbranched azobenzene-containing polymers via self-condensing atom transfer radical polymerization and copolymerization

We report on the synthesis of an azobenzene-containing inimer 6-{4-[4-(2-(2-bromoisobutyryloxy)hexyloxy)phenylazo]phenoxy}hexyl methacrylate (I) and used it to prepare hyperbranched homopolymer and copolymers by self-condensing vinyl polymerization (SCVP) and copolymerization (SCVCP) with its precursor 6-{4-[4-(6-hydroxyhexyloxy)phenylazo]phenoxy}hexyl methacrylate (M) using atom transfer radical polymerization (ATRP). Depending on the comonomer ratio, γ=[M]₀/[I]₀, branched polymethacrylates with number-average weights between 8000 and 20,000 and degree of branching (DB) between 0.08 and 0.49 were obtained by SCVCP, as evidenced by GPC and ¹H NMR analysis. In addition, the photochemical properties of the polymers were also studied by UV-vis spectra and found the structure of polymers affect obviously the trans-cis isomerization properties of the branched polymers.     

Star polymers via atom transfer radical polymerization from adamantane-based cores

A series of novel multifunctional initiators derived from adamantane-based derivatives have been used in the syntheses of various styrenic and (meth)acrylic star polymers by atom transfer radical polymerization (ATRP). Conditions were identified in each system to produce star polymers with nearly monomodal molecular distributions. These synthesized star polymers have glass transition temperatures similar to those known for high-molecular-weight linear polymers. We obtained a series of adamantane-contained star polymers covering a wide range of molecular weights by adjusting the monomer-to-initiator ratio and the solvent polarity. Because of reaction heterogeneity and inevitable termination processes, the occurrence of star-star coupling led to a lower than predicted molecular weight polydispersity. When hydrolyzed from their cores by NaOH, the values of M_w of the arms of the PMMA star polymer did not change with reaction time, at least for the first 48 h of the reaction, which implies that no significant PMMA hydrolysis occurs within this interval of time.     

Grafting polymers from cellulose nanocrystals via surface-initiated atom transfer radical polymerization

Cellulose nanocrystals (CNC) are rod-like nanoparticles extracted from cellulose. Due to their fascinating properties—renewable, biocompatible, non-toxic, biodegradable, excellent mechanical performances, high specific surface area, water dispersible, can be assemble in chiral nematic phases—CNC have shown promise in various fields, including oil recovery, polymer composites reinforcing, hydrogels, aerogels, supercapacitors, energy saving buildings, cosmetics, papermaking, coatings, liquid crystals, and waste water treatment. However, the hydrophilic surface of CNC hinders their broader applications. In this context, surface modification of CNC via polymer grafting can be used to finely tune their surficial properties and endow CNC with a variety of functionalities, such as conductivity, pH or temperature responsiveness, reactivity…In particular, surface-initiated atom transfer radical polymerization (SI-ATRP) is a powerful tool to graft various polymers with a high grafting density and controlled chain length. In this review, the precise control of grafted polymers from CNC via SI-ATRP is first discussed, including issues related to the polymer grafting density, chain length and possibility to perform an asymmetric grafting. Then, the properties and applications of CNC grafted with a variety of polymers are presented. Finally, some challenges and outlook related to the SI-ATRP method applied to the field of CNC is discussed.     

原子转移自由基聚合法合成PS-g-PMMA

以氯乙酰化聚苯乙烯微球（PS-acyl-Cl）为大分子引发剂,甲基丙烯酸甲酯（MMA）为单体,CuCl/CuCl₂及N,N,N′,N′-四甲基乙二胺（TMEDA）为催化体系的原子转移自由基聚合反应,成功在PS-acyl-Cl表面接枝上PMMA分子链而获得聚苯乙烯 接枝 聚甲基丙烯酸甲酯（PS-g-PMMA）。考察了催化剂、反应温度、溶剂用量等条件对接枝反应的影响,优化的反应条件下,使用氯乙酰基担载量3.44 mmol.g^-1的PS-acyl-Cl,15 h可获得增重率687% 的PS-g-PMMA,且反应表现出一级动力学特征（k=513×10^-5 s^-1）。通过改变反应条件,可得到不同PMMA接枝链长的PS-g-PMMA。反应得到的PS-g-PMMA经水解后有望作为高担载量弱酸型离子交换树脂或进一步功能化后作为酶的柔性固定化载体。     

原子转移自由基聚合催化体系的研究进展

采用原子转移自由基聚合(ATRP)、反相ATRP(R-ATRP)可以对聚合物进行分子设计,制备结构和相对分子质量可控的均聚物、嵌段共聚物、接枝和梳状聚合物以及星形和一些高支化的聚合物.该类反应中,催化体系是研究的重点和热点.着重介绍了ATRP和R-ATRP聚合催化体系的研究进展,并且针对其催化剂脱除困难的问题,介绍了催化剂分离方面的最新研究进展.     

Synthesis of triphenyl phosphine oxide‐containing polymers via atom transfer radical polymerization

Bis[(4 ‐β‐(2‐bromopropanoate)ethoxy)phenyl]phenylphosphine oxide was used for the first time as the initiator of atom transfer radical polymerization of styrene and methyl methacrylate in the presence of CuBr/N, N,N′, N″, N″‐pentamethyldiethylenetriamine as catalyst/ligand and dimethyl sulfoxide as solvent. The presence of phosphine oxide linkages in the backbone gives the polymers special properties; low T_g, high char yield, and decreases the oxygen induction time value. A linear increase of number average molecular weight (M_n) versus monomer conversion was observed, and the molecular weight distribution was relatively narrow (M_w/M_n = 1.1–1.3). FTIR, ¹HNMR, gel permeation chromatography, ultraviolet spectroscopies were used for the characterization of the related polymers. The thermal properties of these polymers were investigated by differential scanning calorimetry and thermogravimetric analysis. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

聚丙烯的原子转移自由基接枝共聚

将商品氯化聚丙烯还原后作为原子转移自由基聚合的引发剂,在溴化铜/2,2'－联吡啶的催化下与聚苯乙烯接枝共聚.核磁共振氢谱分析结果表明聚丙烯与聚苯乙烯发生了接枝共聚;接枝率随聚合时间的增加而增大.     

原子转移自由基聚合法制备星形聚苯乙烯

采用原子转移自由基聚合（ATRP）法,以三羟甲基丙烷为核制备引发剂,以苯乙烯为单体,合成三臂聚苯乙烯星形聚合物,并用傅里叶变换红外光谱（FTIR）、核磁共振氢谱（1H-NMR）、凝胶渗透色谱（GPC）对所得引发剂和聚合物的结构进行了表征。结果表明,FTIR证实了三臂引发剂和聚苯乙烯的存在。1H-NMR分析证实,采用ATRP法可以成功合成出目标产物星形聚苯乙烯。GPC分析证明了所得产物的数均分子量为2 700~9 460,基本符合预期值;多分散性指数仅为1.01~1.05,具备活性聚合特征。     

Well-defined dibenzocyclooctyne end functionalized polymers from atom transfer radical polymerization

The dibenzocyclooctyne end functionalized agent 1 was designed as atom transfer radical polymerization (ATRP) initiator. The ATRP was then explored on three types of monomers widely used in free radical polymerization: methyl methacrylate, styrene, and acrylates (n-butyl acrylate and tert-butyl acrylate). The living polymerization behaviors were obtained for the methyl methacrylate and styrene monomers. The SPAAC click reactivity of dibenzocyclooctyne end group were demonstrated by successfully reacting with azide functionalized small chemical agents and polymers. Various topological polymers such as block and brush polymers were produced from strain-promoted azide-alkyne cycloaddition reaction (SPAAC) using the resultant dibenzocyclooctyne end functionalized poly(methyl methacrylate)/polystyrene as building blocks. For the acrylates, however, the polymerization did not hold the living characteristics with the dibenzocyclooctyne end functionalized ATRP initiator 1.