2-乙烯基-2-噁唑啉的合成及聚合

通过亚氨酸酯合成制备了２－乙烯基－２－唑啉（ＶＯＺＯ）单体，对合成过程中的溶剂及分离等问题进行了讨论；进一步在苯溶液中自由基聚合ＶＯＺＯ得到聚乙烯基唑啉（ＰＶＯＺＯ）。用元素分析和红外光谱表征的方法，证实了所得单体和聚合物的分子结构；发现聚合物ＰＶＯＺＯ为分子中仍保留有唑啉环侧基，对水和有机溶剂都有着良好溶解性的线型大分子。     

“活性”原子转移自由基聚合向活性正离子开环聚合转化制备苯乙烯-2-甲基-2-噁唑啉嵌段共聚物(英文)

以苯乙烯的ATRP聚合制备含卤端基的聚苯乙烯，再以此含卤端基的聚苯乙烯引发2－甲基－2－唑啉的正离子开环聚合，合成了苯乙烯与2－甲基－2－唑啉嵌段共聚物，并用IR，GPC对开环产物进行了表征。     

2，2-双（2-噁唑啉）改性回收PET的研究

以扩链剂2，2-双(2-噁唑啉)对回收PET进行扩链增粘，从特性粘度和羧值的变化考察了其扩链效果，并用DSC法研究了不同添加量噁唑啉对PET热性能的影响。结果表明：双噁唑啉对PET有一定的扩链效果，且影响PET的冷结晶行为。     

2-乙烯基-2-噁唑啉的合成及聚合

通过亚氨酸酯合成了２ 乙烯基 ２ 口恶唑啉（ＶＯＺＯ）单体。对合成过程中的溶剂及分离等问题进行了讨论。ＶＯＺＯ在苯溶液中自由基聚合生成聚乙烯基口恶唑啉（ＰＶＯＺＯ）。用元素分析和红外光谱表征的方法,证实了所得单体和聚合物的分子结构;发现聚合物ＰＶＯＺＯ为分子中仍保有口恶唑啉环侧基的对水和有机溶剂都有着良好溶解性的线型大分子。     

2-甲基-2-噁唑啉的合成研究

以N-(2-羟基乙基)乙酰胺为原料,在二水乙酸锌的催化作用下,脱水缩合生成2-甲基-2-噁唑啉,考察了温度、催化剂用量、压力、时间对反应的影响。最佳工艺条件为:m(催化剂):m(N-(2-羟基乙基乙酰胺))=0.15∶1,反应温度为185℃,压力为0.01 MPa,反应时间为2 h,收率可达到95%。并考察了催化剂的重复使用情况。产物经质谱进行了结构表征。     

2-丙烯酰胺基-2-甲基丙磺酸共聚物的水溶液性质研究

以2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为基料，用水溶液引发聚合的方法合成了AMPS／AM／AA／DEAM(2-丙烯酰胺基-2-甲基丙磺酸／丙烯酰胺／丙烯酸／二乙基丙烯酰胺)四元共聚物，对其水溶液性质进行了研究。结果表明此共聚物具有较好的抗高温、抗高盐能力，是一种新型的耐温抗盐驱油用聚合物。     

2－噁唑啉化合物与环氧树脂固化反应研究（Ⅰ）

研究双－２－唑琳和２－乙基－２－唑啉（ＯＸＡ）对环氧树脂（ＥＰＯ）的固化反应，用溶剂萃取法考察ＯＸＡ／ＥＰＯ，反应温度和加速剂对固化反应的影响。结果指出：固化速度随ＯＸＡ用量增加而增大，但当ＯＸＡ／ＥＰＯ＞０．２，ＯＸＡ量对固化速度的影响逐渐减小，已二酸、三嗅酚和对苯二酚对此固化体系有一定的加速作用，其效果取决于固化条件。     

无毒粘合剂的合成研究

本文研究了以醋酸乙烯酯、丙烯酸２－乙基己酯和丙酸为单 过氧化苯甲酰为引发剂,以抽提油为溶剂,经聚合而得到一种无毒的软质材料粘合剂。本文对原料配比及聚合条件进行了讨论。     

本体共聚法合成噁唑啉官能化聚苯乙烯的研究

本文以2—乙烯基—2—(口恶)唑与苯乙烯自由基本体共聚合制得(口恶)唑啉官能化聚苯乙烯(RPS).考察了引发剂、单体比、反应条件对共聚合的影响.RPS用IR、1~H—NMR (13)~C—NMR等方法进行表征并测定其拉伸性能和MFR.     

2,2-双(2-噁唑啉)与苯酐联用改性回收PET的动态热性能研究

以扩链剂2,2 双(2 噁唑啉)(BOZ)与苯酐(PA)联用改性回收PET,系统地考察了增黏改性后回收PET动态流变性能和动态力学性能的影响。结果表明,BOZ与PA联用的改性效果明显优于单用BOZ改性回收PET体系;但因扩链剂的加入,在PET分子链中引入的柔性链段而导致聚合物弹性模量下降。     

Cationic polymerization of 2,4,4-trimethyl-2-oxazoline

Summary The cationic homopolymerization of 2,4,4-trimethyl-2-oxazoline using BF₃Et₂O as initiator at different initiator concentrations, temperatures, times and solvents of polymerization were carried out. The effect of these variables on the polymerization yield and viscosity of the polymers were studied. Polymers were characterized by IR.¹H NMR and¹³C NMR which support that the polymerization reaction occurs by ring opening of oxazoline through oxazolinium intermediates.     

Star poly(2‐ethyl‐2‐oxazoline)s—synthesis and thermosensitivity

A series of star‐shaped poly(2‐ethyl‐2‐oxazoline)s was prepared by cationic polymerization. The polymerization was initiated by dipentaerythrityl hexakis(4‐nitrobenzene sulfonate) and a tosylated hyperbranched polymer of glycidol. The polymerization proceeded in a controlled manner. The star structure of the products was determined by nuclear magnetic resonance. The molar mass distributions that were measured by gel permeation chromatography with multiangle laser light scattering were narrow, and the experimental values of the molar masses were close to those predicted. The very compact structure of the polymers obtained (compared with the linear counterparts) confirmed the star formation. The star poly(2‐ethyl‐2‐oxazoline)s show a phase transition temperature in the range 62–75 °C. Comparison of this phase transition temperature with that of the linear poly(2‐ethyl‐2‐oxazoline)s with the same molar masses indicates the influence of molar mass and topological structure of the macromolecule on temperature behavior. The prepared copolymers are spherical, which might be useful for the controlled transport and release of active compounds. Copyright © 2011 Society of Chemical Industry     

Polymerization of methyl and phenyl oxazoline initiated with carboxylic acid chlorides

Methyl and phenyl oxazoline were polymerized using carboxylic acid chlorides as initiators. The first step of the reaction was shown to consist in a fast reaction of the carboxylic acid chloride with the oxazoline. Resulting product, which was isolated and identified, act as the proper initiator of the polymerization of the oxazoline, which proceeds via covalent or, when chloride counter ion is replaced with iodide or triflate, ionic active species. Apparent rate constants of the chain growth were determined. When methacryloyl chloride is used as initiator macromonomers are obtained, which were copolymerized with styrene. Macromolecular carboxylic acid chlorides initiate the polymerization of oxazolines, yielding graft polymers. Received: 7 October 1996/Accepted: 15 October 1996     

Factorial design optimization of polystyrene microspheres obtained by aqueous dispersion polymerization in the presence of poly(2‐ethyl‐2‐oxazoline) reactive stabilizer

The present study highlights the use of statistical design to establish an effective model for the synthesis of polystyrene microspheres by aqueous dispersion polymerization using poly(2‐ethyl‐2‐oxazoline) reactive stabilizer. The significant parameters (e.g. solvent polarity, stabilizer and initiator concentration) influencing the characteristic responses of the process such as yield, particle size and size distribution, as well as the interactions between the variables, were identified. The macromonomer concentration and solvent polarity influence both particle size and size distribution, whereas initiator concentration influences the yield. Analysis of the variance of process variables indicates that the models can be successfully used to describe the dispersion polymerization process. Moreover, the factorial design allows the development of microspheres with optimal properties with respect to size and size distribution. The experimental data regarding yield, particle size and size distribution of the optimized dispersion polymerization shows less than 7% difference compared with the predicted responses. In view of these results, the implementation of statistical design models represents an efficient solution for optimizing microparticle synthesis while aiming for industrial applications. © 2020 Society of Chemical Industry     

Synthesis of amphiphilic silane coupling agents based on poly(2-ethyl-2-oxazoline) and their reactions with tetraethoxysilane

Summary Ring-opening polymerization of 2-alkyl-2-oxazoline (alkyl=ethyl,n-butyl,n-octyl) was carried out with an initiator of methyl tosylate followed by the treatment with 3-aminopropyltriethoxysilane to produce a novel type of polymeric silane coupling agents. Similary, telechelic triethoxysilyl-terminated poly(2-alkyl-2-oxazoline)s were prepared by using a bifunctional initiator. The molecular weights of the produced polymers could be effectively controlled by the feed ratio of the initiator to the monomer. These end-functionalized polymers were reacted with tetraethoxysilane with an acid catalyst by the solgel method. In the case of poly(2-ethyl-2-oxazoline), a homogeneous and transparent polymer hybrid was obtained. This polymer hybrid absorbed both of water and organic solvents, which showed amphiphilic adsorption property.     

Influence of initiators on the growth of poly(ethyl 2-cyanoacrylate) nanofibers

The type of anionic initiator used to polymerize ethyl 2-cyanoacrylate was found to influence the morphology of the polymer formed via vapor phase polymerization. Depending upon the type of initiator, polymerization of ethyl 2-cyanoacrylate resulted in either the formation of neat polymer nanofibers (～200 nm in diameter) or thin films. Based on the classification of anions using Hard Soft Acid Base principles, we found that harder anions favored polymer film formation while softer ones favored polymer nanofibers. Infrared (IR) spectroscopy, scanning electron microscopy (SEM) and gel permeation chromatography (GPC) were used to characterize the structure, morphology and molecular weight of the synthesized polymers, respectively. Finally, a mechanism of formation of different polymer morphologies is proposed.     

Synthesis, characterization, and controllable drug release of dendritic star-block copolymer by ring-opening polymerization and atom transfer radical polymerization

A series of well-defined dendritic star-block copolymers were successfully synthesized by combination of living ring-opening polymerization (ROP) and atom transfer radical polymerization (ATRP) with the hydroxyl-terminated dendrimer polyester. Dendritic star-shaped poly(l-lactide)s (PLLAs) were prepared by bulk polymerization of l-lactide (l-LA) with dendrimer polyester initiator and tin 2-ethylhexanoate catalyst. The number-average molecular weight of these polymers linearly increased with the molar ratio of l-LA to dendrimer initiator. Dendritic star-shaped PLLA was converted into a PLLABr macroinitiator with 2-bromopropionyl bromide. Dendritic star-block copolymers could be obtained via ATRP of 2-(N,N-dimethylamino)ethyl methacrylate (DMAEMA). The molecular weight distributions of these copolymers were narrow. The molecular weights of dendritic star-shaped polymers and star-block copolymers could be controlled by the molar ratios of monomer to initiator and monomer conversion. The thermal properties of these dendritic star-shaped polymers and star-block copolymers were investigated. The behavior of model drug chlorambucil release from the copolymer indicated that the rate of drug release could be effectively controlled by altering the pH values of the environment.     

Electropolymerization of 2‐methacryloyloxy(ethyl) acetoacetate on aluminum using a novel initiation method

Electropolymerization has been used as a method to form polymers on graphite fibers and metals. Most of the previous studies have involved either the use of sulfuric acid as an initiator or direct reduction or oxidation of monomers to form the polymers. In this article, α‐bromoisobutyronitrile (BrIBN) was used as a new electrochemical initiator to form polymer coatings on an aluminum cathode. The reduction of BrIBN on a glassy carbon electrode was examined using cyclic voltammetery. It was found that BrIBN could be reduced to isobutyronitrile radicals at potentials below the reduction potential of water. The reduction behavior of BrIBN was found to be similar in aqueous, semiaqueous, and nonaqueous solutions. 2‐Methacryloyloxy(ethyl) acetoacetate was then electropolymerized on aluminum using the BrIBN as the initiator and lithium perchlorate as a supporting electrolyte. Defect‐free coatings were formed at half‐cell potentials of less than −1.20 V. The effect of various process variables on the polymerization kinetics under potentiostatic conditions is reported. The coating thickness increased with polymerization time, monomer concentration, and initiator concentration. A strong dependence of thickness on monomer concentration was observed. As expected, there was weak dependence on the initiator concentration. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 1665–1675, 1999     

Synthesis of telechelic polyacrylates with unsaturated end-groups

A convenient, one-pot synthesis of telechelic and semi-telechelic polyacrylates with unsaturated end-groups has been developed. Atom transfer radical polymerization of methyl or n-butyl acrylate was initiated with either ethyl α-bromomethylacrylate or methyl dichloroacetate, as a monofunctional or difunctional initiator, respectively, and mediated with various Cu/amine complexes. Addition of excess ethyl 2-bromomethylacrylate was found to not only immediately quench the polymerization but also installed 2-carbethoxyallyl moieties on the ends of the polymer chains. The telechelic polymers were found to undergo thermally or photochemically induced crosslinking reactions.     

Synthesis and characterization of poly(2-methylaziridine)

Summary The cationic polymerization of 2-methylaziridine using boron trifluoride etherate as initiator at different monomer/initiator ratios, temperatures, solvents, and times of polymerization was carried out. The effect of these variables on the polymerization yield and viscosity of the polymers was studied. All the polymers were characterized by elemental analysis, FT-IR, ¹H-NMR, ¹³C-NMR spectroscopy, thermogravimetric analyses and differential scanning calorimetry.