A starlike amphiphilic graft copolymer with hydrophilic poly(acrylic acid) backbones and hydrophobic polystyrene side chains

A well‐defined starlike amphiphilic graft copolymer bearing hydrophilic poly(acrylic acid) backbones and hydrophobic polystyrene side chains was synthesized by successive atom transfer radical polymerization followed by the hydrolysis of poly‐(methoxymethyl acrylate) backbone. A grafting‐from strategy was employed for the synthesis of a graft copolymer with narrow molecular weight distribution. Hydrophobic polystyrene side chains were connected to the backbones through stable C? C bonds. The poly(methoxymethyl acrylate) backbones can be easily hydrolyzed with HCl without affecting the hydrophobic polystyrene side chains. This kind of amphiphilic graft copolymer can form stable sphere micelles in water. The sizes of the micelles were dependent on the ionic strength and pH value. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3687–3697, 2007     

2×2阶上三角算子矩阵的谱扰动

研究了Hilbert空间H⊕K上的2×2阶上三角算子矩阵MC=(A O C B)当A,B给定,C为任意有界线性算子时,对MC的点谱、剩余谱、连续谱的扰动分别给出了描述.     

Bio‐based aromatic copoly(ether ester)s with enhanced toughness and degradability: Influence of insertion of phenoxy‐ether linkage and eugenol‐derived composition on properties

Two series of renewable nipagin and eugenol‐based copoly(ether ester)s, PDN1_1?xE1_x and PDN1_1?xE2_x (x = 0%, 10%, 20%, 30%, 40%, 50%), were prepared in the melt with 1,10‐decanediol as a comonomer. The synthesized poly(ether ester)s have weight‐average molecular weights (M_w) in the range of 20,400–37,200 g mol^?1, and dispersity (D) values between 1.7 and 1.9. Thermal gravimetric analysis (TGA) reveal that all the poly(ether ester)s exhibit a two‐step degradation mechanism with an initial degradation temperature above 350 °C. Results from differential scanning calorimetric (DSC) and wide‐angle X‐ray diffraction (WXRD) analyses demonstrate that the poly(ether ester)s are all semicrystalline materials with glass transition temperature (T_g) values ranging between ?21.3 and ?8.3 °C. The insertions of phenoxy‐ether linkage and eugenol‐derived composition have significant influence on the T_g, crystallinity, Young's modulus, and tensile strength, as well as the toughening effect and degradability. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2171–2183     

Star‐like PAA‐g‐PPO well‐defined amphiphilic graft copolymer synthesized by ATNRC and SET‐NRC reaction

A series of well‐defined amphiphilic star graft copolymers consisting of hydrophilic poly(acrylic acid) backbone and hydrophobic poly(propylene oxide) side chains were synthesized by the sequential reversible addition‐fragmentation chain transfer (RAFT) polymerization and atom transfer nitroxide radical coupling (ATNRC) or single electron transfer‐nitroxide radical coupling (SET‐NRC) reaction followed by the selective hydrolysis of poly(tert‐butyl acrylate) backbone. A Br‐containing acrylate monomer, tert‐butyl 2‐((2‐bromopropanoyloxy)methyl)acrylate, was first homopolymerized via RAFT polymerization using a new star‐like chain‐transfer agent with four arms in a controlled way to give a well‐defined star‐like backbone with a narrow molecular weight distribution (M_w/M_n = 1.23). The grafting‐onto strategy was used to synthesize the well‐defined PtBA‐g‐PPO star graft copolymers with narrow molecular weight distributions (M_w/M_n = 1.14–1.25) via ATNRC or SET‐NRC reaction between the Br‐containing PtBA‐based star‐like backbone and poly(propylene oxide) with 2,2,6,6‐tetramethylpiperidine‐1‐oxyl end group using CuBr/PMDETA or Cu/PMDETA as catalytic system. PAA‐g‐PPO amphiphilic star graft copolymers were obtained by the selective acidic hydrolysis of star‐like PtBA‐based backbone in acidic environment without affecting the side chains. The critical micelle concentrations in aqueous media and brine were determined by the fluorescence probe technique. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2084–2097, 2010     

Thermoresponsive PPEGMEA‐g‐PPEGEEMA well‐defined double hydrophilic graft copolymer synthesized by successive SET‐LRP and ATRP

A series of well‐defined double hydrophilic graft copolymers containing poly[poly(ethylene glycol) methyl ether acrylate] (PPEGMEA) backbone and poly[poly(ethylene glycol) ethyl ether methacrylate] (PPEGEEMA) side chains were synthesized by the combination of single electron transfer‐living radical polymerization (SET‐LRP) and atom transfer radical polymerization (ATRP). The backbone was first prepared by SET‐LRP of poly(ethylene glycol) methyl ether acrylate macromonomer using CuBr/tris(2‐(dimethylamino)ethyl)amine as catalytic system. The obtained comb copolymer was treated with lithium diisopropylamide and 2‐bromoisobutyryl bromide to give PPEGMEA‐Br macroinitiator. Finally, PPEGMEA‐g‐PPEGEEMA graft copolymers were synthesized by ATRP of poly(ethylene glycol) ethyl ether methacrylate macromonomer using PPEGMEA‐Br macroinitiator via the grafting‐from route. The molecular weights of both the backbone and the side chains were controllable and the molecular weight distributions kept narrow (M_w/M_n ≤ 1.20). This kind of double hydrophilic copolymer was found to be stimuli‐responsive to both temperature and ion (0.3 M Cl^? and SO). © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 647–655, 2010     

四苯氧基酞菁镁、锰、铝和锌的合成和性质

合成了新的酞菁配合物４，４，４，４－四苯氧基酞菁镁［ＴＰｈＯＰｃＭｇ（Ⅱ）］，锰［ＴＰｈＯＰｃＭｎ（Ⅱ）Ａｃ］，铝［ＴＰｈＯＰｃＡｌ（Ⅲ）Ｃｌ］，锌［ＴＰｈＯＰｃＺｎ（Ⅱ）］测定了它们的ＩＲ，ＵＶ－Ｖｉｓ光谱，在ＤＭＦ中的氧化还原半波电势（Ｅ１／２），电子转移速度常数，在乙腈中的荧光性质及锰的配合物在不同电位下的光谱变化情况。