Modeling the Synthesis of Butyl Methacrylate Macromonomer by Sequential ATRP‐CCTP

The atom transfer radical polymerization of butyl methacrylate mediated by Cu(I)Br/N,N,N′,N″,N″‐pentamethyldiethylenetriamine in anisole at 70 °C with the subsequent addition of bis(difluoroboryldiphenylglyoximato)cobalt(II) after 2 h is modeled using Predici software, to gain additional insight to the system used experimentally to produce macromonomer chains with narrow dispersity. The mechanistic model, using kinetic coefficients from the literature and activation and deactivation rate coefficients estimated from this work, provides a good representation of experimental results. The simulations demonstrate that the time (conversion) at which cobalt chain transfer agent is added to the system is critical to control the number‐average molar mass of the final product and also confirm that chains of higher length in the final product are more likely to be nonfunctionalized, in agreement with experimental observations. The model predicts the production of a significant fraction of macromonomer oligomers with lengths of 1–3 units, also consistent with experiments.     

分散共聚体系中高分子纳米颗粒的合成与反应机理

用自由基聚合及端基反应法合成了苯乙烯基封端的聚N 异丙基丙烯酰胺和聚乙二醇大分子单体 .核磁共振分析表明 ,基本上每一个大分子单体末端有一个双键 .将大分子单体与苯乙烯进行分散共聚反应 ,一步法制备得到了表面具有接枝链的高分子纳米级颗粒 .研究结果表明 :大分子单体浓度、苯乙烯单体浓度、引发剂浓度、大分子单体末端官能团种类和反应温度等因素对形成微球的直径有明显的影响 ,高分子微球的直径和形态可通过改变上述反应条件加以控制 .通过实验数据计算得出了高分子微球直径与各种反应因素间的定量关系式 ,对不同体系的成核机理进行了比较 ,得到的结果对其它相似共聚反应体系有一定的指导意义 .     

Synthesis and polymerization of oligo(oxyethylene) macromonomer bearing sodium sulfonate

Oligo(oxyethylene) macromonomers bearing sodium sulfonate group have been synthesized through four reactions: (1) ring-opening polymerization of oxirane, (2) etherification of monomethoxyl oligo(oxyethylene) and epichlorohydrin, (3) sulfonation of cycloxyl compound, and (4) end-capping of sodium oligo(oxyethylene) sulfonate by methacrylic group. A desired length of oligo(oxyethylene) in the macromonomers can easily be achieved by controlling the ratio of reactants in the ring-opening step. The structures of the products of each reaction were identified by IR, ¹H-NMR, and GPC. Polymers of the monomers were also characterized by GPC and DSC. © 1993 John Wiley & Sons, Inc.     

丙烯酸酯类微凝胶的制备及其表征

通过１２－羟基硬酯酸的聚合物与甲基丙烯酸缩水甘油酯（ＧＭＡ）的开环加成,制得大分子单体,用此大分子单体与甲丙基烯酸甲酯（ＭＭＡ）、ＧＭＡ共聚制得分散稳定剂。在此分散稳定剂的存在下,通过分散聚合方法,制备了亚微米级的丙烯酸酯类微凝胶。用酸碱滴定、傅立叶变换红外光谱（ＦＴＩＲ）、凝胶渗透色谱（ＧＰＣ）、平均粒径分布等方法对该凝胶进行了测定,并对微凝胶在涂料中的应用进行了测试。结果表明：微凝胶能够显著改     

多组份含金属盐透明树脂的合成

本文将双烯聚醚砜大分子单体(BPS-MA)引入含金属(Pb、Ba等)盐单体的苯乙烯体系中进行聚合,发现单体配比与树脂透明性密切相关。对于Pb(MA)_2/St/MA/BPS-MA四元体系,欲获得透明树脂,BPS-MA用量大于20％时,摩尔比MA/[Pb(MA)_2]可由原来的5.5降至2.2左右,并且可获得n_D>1.60的透明材料。光学性能测试结果表明,Pb(MA)_2、BPS-MA量增加,n_D增大,阿贝数v_D略降低;MA量增加,n_D下降v_D略增加。适当的配比可望制备出性能优异的多组份含金属盐透明聚合物材料。     

Micellar polymerization of amphiphilic poly(vinyl alcohol) macromonomer having a methacrylate end group prepared by aldol‐type group‐transfer polymerization

Amphiphilic and heterotactic‐rich poly(vinyl alcohol) (PVA) macromonomer, that is, PVA having a phenyl or phenoxyethyl methacrylate unit as the polymerizable end group, was synthesized via the aldol‐type group‐transfer polymerization (aldol‐GTP) technique. Aldol‐GTPs of vinyloxytriethylsilane (VOTES) were carried out in dichloromethane with 4‐methacryloylbenzaldehyde and 4‐(2‐methacryloylethoxy)benzaldehyde as the initiators with various Lewis acids. The polymerizations proceeded smoothly to give silylated PVA macromonomers (number‐average molecular weights: 1.3 × 10³–1.96 × 10⁴). Poly(VOTES) was easily desilylated to give heterotactic‐rich PVA macromonomer in good yield. The critical micelle concentration of the PVA macromonomer was determined by surface‐tension measurement. Micellar polymerization of the amphiphilic macromonomer gave comb‐shaped (graft) polymer having PVA side chains effectively (conversion: 80–82%), whereas polymerization in dimethyl sulfoxide (homogeneous state) did not. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 4477–4484, 2002     

Graft copolymers having hydrophobic backbone and hydrophilic branches. X. Preparation and properties of water-dispersible polyanionic microspheres having poly(methacrylic acid) branches on their surfaces

The free radical copolymerization of poly(t-butyl methacrylate) (PBMA) macromonomer with styrene in ethanol give monodispersed microspheres with 0.8-1.6 μm diameter. The resulting microspheres were treated with HCl solution to convert into anionic microspheres having poly(methacrylic acid) chains. ESCA analysis of the microsphere surface suggested that PBMA chains were favorably located on the surface of the microspheres. The particle size of the microspheres decreased with increasing molecular weight and concentration of the macromonomer. Water dispersibilities of the microspheres were evaluated by measuring the relative turbidity of the suspension of microspheres as a function of pH. The results show that they were strongly dependent on pH. © 1995 John Wiley & Sons, Inc.     

Macromolecular engineering of polylactones and polylactides. XV. Poly(D,L)-lactide macromonomers as precursors of biocompatible graft copolymers and bioerodible gels

The functional aluminum alkoxide, Et₂Al? O? (CH₂)₂? O-C(O)? C(CH₃)?CH₂, is a very effective initiator for the (D ,L )-lactide (LA) polymerization in toluene at 707deg;C. The coordination-insertion type of polymerization is living and exclusively yields linear P (D ,L )-lactide macromonomers of a predictable molecular weight and a narrow molecular weight distribution. IR and ¹H-NMR studies show that the methacryloyl group of the initiator is selectively and quantitatively attached to one chain end, whereas the second extremity is systematically a hydroxyl function resulting from the hydrolysis of the living growing site. α,ω-Dimethacryloyl-P(D ,L )-lactides, i.e., α,ω-macromonomers, have also been successfully synthesized by the additional control of the termination step, i.e., by reaction of Al alkoxide end groups with methacryloyl chloride. α-Macromonomer and α,ω-macromonomer P(D ,L )-lactides are easily free-radical copolymerized with 2-hydroxyethyl methacrylate (HEMA), resulting in a hydrophilic poly (HEMA) backbone grafted with hydrophobic P(D ,L )-lactide subchains and a biodegradable amphiphilic network, respectively. © 1994 John Wiley & Sons, Inc.     

热敏性聚(N-乙烯基异丁酰胺)接枝高分子微球的合成

用自由基聚合和端基反应法合成了大分子单体聚 (N 乙烯基异丁酰胺 ) (PNVIBA) ,将其与苯乙烯在乙醇 水的混合溶剂中进行分散共聚 ,得到了PNVIBA接枝聚苯乙烯 (PNVIBA g PSt)高分子微球 .用GPC、激光光散射和电子显微镜等对聚合物的分子量和微球直径及形态进行了表征 .研究结果表明 ,大分子单体PNVIBA和PNVIBA g PSt高分子微球具有明显的热敏性 ,并且发现PNVIBA g PSt微球直径和形态可通过改变反应条件加以控制 ,得到了一种新形态的亚微米级高分子微球     

Synthesis of graft copolymers having phospholipid polar group by macromonomer method and their properties in water

Water-soluble graft copolymers with phospholipid polar group were synthesized by the macromonomer method and their properties in water were investigated by surface tension and fluorescence spectroscopic measurements. At first, 2-methacryloyloxyethyl phosphorylcholine (MPC) was polymerized in the presence of 3-mercapt propionic acid as a chain transfer agent and carboxyl group-terminated oligo (MPC) was obtained. The oligo (MPC) reacted with glycidyl methacrylate to convert the carboxyl group to a polymerizable methacryloyl group. The MPC macromonomer obtained was copolymerized with hydrophobic n-butyl methacrylate (BMA) and a graft copolymer was obtained. The graft copolymer, poly(MPC-graft-BMA), was water-soluble when the MPC unit mole fraction was above 0.40. The surface tension of the aqueous solution of poly(MPC-graft-BMA) did not depend on the polymer concentration below 0.1 wt %. This tendency was the same as that which appeared in aqueous poly(MPC) solution. The fluorescence intensity of hydrophobic probes observed in an aqueous solution of the poly (MPC-graft-BMA) was also the same level as that observed in the case of poly(MPC). These results clearly indicated that the poly(MPC-graft-BMA) took a domain structure like micelle in water, i.e., the hydrophobic poly(BMA) backbone was in the core part and the hydrophilic poly(MPC) chain formed the shell part of the micelle. © 1994 John Wiley & Sons, Inc.