TA-EG-GMA合成超支化碱溶性感光聚合物

通过1,2,4-偏苯三酸酐和乙二醇反应合成超支化聚合物,利用合成聚合物分子外围的羧基与甲基丙烯酸缩水甘油酯反应,在超支化聚合物分子外围引入反应性甲基丙烯酰氧基.研究了树脂组成对感光性和碱溶性的影响.结果表明:调整反应物料配比及反应性甲基丙烯酰氧基含量,可以获得较好的碱溶性和光固化性能.     

偏苯三酸酐-环氧丙烷丁基醚合成超支化碱溶性聚酯

通过1,2,4 偏苯三甲酸酐(TA)和环氧丙烷丁基醚(BGE)合成超支化碱溶性聚酯,利用合成聚合物分子外围的羧基与烯丙基缩水甘油醚(AGE)反应,在超支化聚合物分子外围引入反应性烯丙基醚.研究了树脂组成对感光性和碱溶性的影响;结果表明:调整反应物料配比,可以获得较好的碱溶性和光固化性能,其树脂的反差γ可达到3.92.     

超支化聚(酰胺-酯)的合成及其光致变色性能研究

采用丁二酸酐、三羟甲基氨基甲烷为主要原料,在冰水浴条件下合成AB_3型单体,然后进行熔融缩聚制得超支化聚(酰胺-酯)(HBP);再将含羧基的螺吡喃光致变色基元通过反应活性基团羧基与AB_3超支化聚合物末端羟基的反应而引入到AB_3超支化聚合物末端上,得到具有光致变色性能的超支化聚合物(MHBP)。利用红外、核磁等对其结构进行了表征,利用紫外可见分光谱对超支化聚合物光致变色性进行了研究。结果表明:MHBP同时具有超支化聚合物的性能和光致变色性能。     

3-(2''-甲基)丙烯酰氧基-5-甲基异恶唑的合成

本文合成了3－（2’－甲基）丙烯酰氧基－5－甲基异恶唑，给出了优化合成条件，就3－羟基－5－甲基异恶唑与甲基丙烯酰氯的O－／N－酰化反应的影响因素进行了讨论，并初步测定了3－（2’－甲基）丙烯酰氧基－5－甲基异恶唑的生物活性。     

γ-甲基丙烯酰氧基丙基三甲氧基硅烷的合成研究

以甲基丙烯酸烯丙酯与三氯氢硅为原料,通过硅氢加成反应得到甲基丙烯酰氧基丙基三氯硅烷,再将它与甲醇醇解反应制备甲基丙烯酰氧基丙基三甲氧基硅烷,讨论了影响硅氢加成反应、醇解反应的主要因素,并得出最佳合成工艺条件。     

一代端羧基超支化聚合物的制备与表征

首先采用二乙醇胺(DEA)与丙烯酸甲酯(MA)反应得到AB2型单体N,N-二羟乙基-3-氨基丙酸甲酯;然后以三羟甲基丙烷为核,在对甲苯磺酸的催化下,与N,N-二羟乙基-3-氨基丙酸甲酯反应得到端羟基超支化聚合物(HPAE-OH);最后采用顺丁烯二酸酐对端羟基超支化聚合物进行端基改性,制得端羧基超支化聚合物(HPAE-C)。优化的一代端羧基超支化聚合物的合成条件为:催化剂质量分数0.7%(基于反应物料总质量),反应投料比n(OH)∶n(马来酸酐)=1∶1.1,反应时间4 h,反应温度80℃。采用IR、1HNMR和13CNMR对端羧基超支化聚合物的分子结构进行了表征,采用表面张力仪研究了聚合物的表面活性。     

一种新型阳离子聚丙烯酰胺的合成及表征

将具有球型分子结构的超支化聚合物接枝到阳离子聚丙烯酰胺上,目的是当用阳离子聚丙烯酰胺处理油田污水时,抑制分子的卷曲速度,提高絮凝性能。作者首先以二甲基二烯丙基氯化铵(DMDAAC)、丙烯酰胺(AM)和丙烯酸(AA)为单体,聚合得阳离子聚丙烯酰胺,该聚合物具有线型分子结构。再以甲基丙烯酰氧乙基三甲基氯化铵(DMC)与端部氨基的超支化聚合物反应,得到端部带有阳离子的超支化聚合物,该聚合物具有类似球型的分子结构。然后将阳离子超支化聚合物接枝到线形阳离子聚丙烯酰胺上,得到一种接枝改性的阳离子聚丙烯酰胺。用红外分光光度仪分析证明得到了预期的产物结构,并测定了产物的特性粘度、阳离子度。     

一代端羧基超支化聚合物的制备与表征

首先采用二乙醇胺(DEA)与丙烯酸甲酯(MA)反应得到AB2型单体N,N-二羟乙基-3-胺基丙酸甲酯,然后以三羟甲基丙烷为核,在对甲苯磺酸的催化下,与N,N-二羟乙基-3-胺基丙酸甲酯反应得到端羟基超支化聚合物（HPAE-OH）,最后采用顺丁烯二酸酐对端羟基超支化聚合物进行端基改性,制得端羧基超支化聚合物（HPAE-C）。优化了一代端羧基超支化聚合物的合成条件：催化剂用量为0.7%,反应投料比n(OH) ∶n(马来酸酐)=1∶1.1,反应时间为4h,反应温度为80℃。采用 IR、1H-NMR和13C-NMR仪器分析法对端羧基超支化聚合物的分子结构进行了表征,采用表面张力仪研究了聚合物的表面活性。     

高硅烷含量有机硅-丙烯酸酯聚合物的制备研究

采用溶液聚合法以偶氮二异丁腈为引发剂,用γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)、γ-甲基丙烯酰氧基丙基甲基二甲氧基硅烷(KH-571)、(甲基)丙烯酸酯类单体,合成有机硅单体含量为45%的有机硅-丙烯酸酯聚合物.考察了引发剂用量及其种类与转化率之间的关系,硅烷配比、溶剂配比对体系的影响.FT-IR表明:有机硅单体参与了共聚.     

端羧基超支化聚(胺-酯)合成及对环氧树脂的增韧

基于迈克尔加成、酯交换和巯基-烯点击化学反应,合成了第三代端羧基超支化聚(胺-酯),对其结构进行表征,并将其用于环氧/甲基四氢苯酐固化体系的增韧研究。研究结果表明:该端羧基超支化聚合物G3可加快固化反应;当添加w(G3)=3%(相对于环氧树脂质量而言)时,固化物在保持弯曲强度和耐热性不下降的前提下,冲击强度显著提高。     

Molecular dynamics simulation for investigating and assessing reaction conditions between carboxylated polyethersulfone and polyethyleneimine

Recently, nano-filtration membranes are made by the reaction between a reactive functional group on the surface of a tight ultrafiltration membrane and a charged branched polymer. This reaction makes the selective layer of the nanofiltration membrane, which plays an essential role in membrane performance. A molecular dynamics simulation with a reactive force field was used to investigate the reaction of carboxylated polyethersulfone as the functional group of the ultrafiltration membrane with polyethyleneimine. Experimental elucidation of the reaction between the PEI amine and carboxyl groups is challenging, and an MD simulation was thus employed. Furthermore, the simulation results show that the PEI and carboxylated polyethersulfone polymers react with each other in a temperature-dependent manner. While no reaction occurs at 298 K, carboxylated polyethersulfone and PEI begin to react when the temperature is increased from 298 to 323 K. Furthermore, a reversible reaction was observed with a subsequent increase in temperature to 353 K.     

Preparation and properties of benzophenone chromophoric group branched polymer for self‐decontamination

To prepare self‐decontamination materials with highly reactive chemical species, such as radicals, the benzophenone chromophoric group branched polymer was synthesized by Friedel–Crafts acylation of polystyrene with benzoyl chloride. The resultant polymer could be prepared into a casting film, and the polymer solution and film were characterized by FTIR, NMR, UV–VIS, XRD, and DSC. From the analyses, it was verified that the benzophenone chromophoric group branched polymer was successfully prepared, and the resultant polymer revealed radical reactivities such as antibacterial effect and decoloration of dye, under UV irradiation. POLYM. ENG. SCI., 47:1750–1755, 2007. © 2007 Society of Plastics Engineers     

Synthesis of biocompatible dendrimers with a peripheral network formed by linking of polymerizable groups

Toward the production of unimolecular nanocapsules with biocompatible surface, we prepared a fourth generation polyamidoamine dendrimer having both a poly(ethylene glycol) (PEG) with the number average molecular weight of 2000 and a methacryloyl group at every chain end of the dendrimer through an l-lysine residue. The introduced methacryloyl groups of the dendrimer were successfully polymerized by using free radical initiators, such as azobisisobutyronitrile and dibenzoyl peroxide, as judged by ¹H NMR. GPC revealed that the molecular weight of the dendrimers having the polymerizable groups did not change after their polymerization, indicating that the polymerization of the methacryloyl groups took place within the single dendrimer. Polymerization of the methacryloyl groups resulted in a significant reduction of the affinity of the dendrimer to a guest molecule, rose bengal, suggesting that the peripheral network formed by the linking of methacryloyl groups hides the dendrimer interior. In addition, when the methacryloyl groups of the dendrimer were polymerized in the presence of rose bengal, the guest molecule was found to be tightly associated with the dendrimer.     

Controlled radical polymerization of p-(iodomethyl)styrene—a route to branched and star-like structures

p-(Iodomethyl)styrene was polymerized under the action of a radical initiator (AIBN). The polymerization proceeds with degenerative chain transfer and leads to well defined branched polymers with functional primary and secondary iodomethyl groups as revealed by NMR studies. The obtained polymer can be further used as macroinitiator for radical polymerization of styrene. This polymerization proceeds in controlled way to polystyrene star polymers with reactive groups at the end of their arms. The characterization of branched and star structures was performed by NMR and GPC with absolute molar mass detection (MALLS).     

A new approach to functionalize multi-walled carbon nanotubes by the use of functional polymers

A new method to graft a large number of long polymer chains or small functional molecules onto multi-walled carbon nanotubes (MWNTs) indirectly is reported. First, MWNTs were slightly functionalized by reversible addition-fragmentation chain transfer (RAFT) copolymerization of styrene and maleic anhydride using the dithioester groups attached to MWNTs as RAFT agents. The highly reactive maleic anhydride groups could further react with a large number of long polymer chains or small functional molecules with hydroxyl or amino group easily. The resulted MWNTs have good solubility in organic solvents and water; the perfect structure of MWNTs is altered very little from the information of Raman spectra.     

Esterification and transesterification of 9(10)-carboxystearic acid and its methyl esters. Kinetic studies

9(10)-Carboxystearic acid and its mono- and dimethyl esters were esterified and transesterified with 1-butanol, 2-methoxyethanol, 2-chloroethanol, 2,2-dimethylpentanol, 2-ethylhexanol and 1-octanol. Rate studies for the sulfuric acid-catalyzed esterification of 9(10)-carboxystearic acid to alkyl 9(10)-carboxystearate and alkyl 9(10)-carboalkoxystearate indicate than on an average the terminal carboxyl is approximately 26–27 times more reactive than the branched carboxyl group. Esterification is highly dependent on catalyst concentration. Steric hindrance in 2,2-dimethylpentanol and the electrophilic character of 2-methoxyethanol and 2-chloroethanol markedly retard the rate. In addition to the expected diesters, 2-chloroethanol yields esters containing extra-O-CH₂CH₂- groups. The rate of transesterification of the terminal ester group of mono- and dimethyl esters of 9(10)-carboxystearic acid is about two times faster than the rate of esterification of the branched carboxyl group. Transesterification of the branched 9(10)-ester group is extremely slow. Presented at the AOCS Meeting, Atlantic City, October 1971. N. Market. Nutr. Res. Div., ARS, USDA.     

Reaktive Mikrogele,X. Anionische Polymerisation von 1,4-diisopropenylbenzol und 1,4-Divinylbenzol in verdünnter lösung

By anionic polymerization of 1,4-divinylbenzene reactive microgels were obtained having an unusual high amount of pending vinyl groups. With low initiator concentration weakly branched or even linear polymers were formed. The tendency of the second double bond to react during polymerization is still less in 1,4-diisopropenylbenzene, where essentially linear polymers could be isolated. The difference to radical emulsion polymerization of these monomers is emphasized and the unusual behaviour of tetrafunctional monomers in anionic polymerization is discussed.     

Photovernetzung von Siliconen. VII. Zum Einfluß der Siliconkette – eine kinetische Studie

Photocrosslinking of Silicones. VII. The Influence of the Silicone Backbone – a Kinetic Study The photo-induced radical crosslinking of silicone containing pendant acrylate groups was investigated by nanosecond flash photolysis and photocalorimetry. From the results of the flash photolysis is inferred that the photochemically formed benzoyl radicals react with the acrylate groups of the system. A possible H-abstraction from the methyl groups of the silicone backbone was not observed. The silicone backbone functions only as an internal solvent. Calorimetric measurements with model systems support these results. The polymerization process is inhibited by oxygen. From calorimetric results is inferred that oxygen both inhibits and terminates the polymerization process. Due to their high oxygen solubility the silicone units increase the oxygen influence on the crosslinking. The calorimetric measurements shows also that a direct bond between silicone backbone and the acrylate group reduces the oxygen influence. Also, in absence of oxygen a direct bonded acrylate group accelerates the polymerization rate.     

蔗渣浆制造黏液纤维的研究

<正>在黏液纤维制造中,用蔗渣浆代替木浆作原料,常被人怀疑甚至否定其可能性,其主要根据为草类纤维的形态结构不同於木材纤维,而以天然纤维的形态结构作为对原料适合与否的判断标准。我们认为:黏液丝浆的良好制备条件均应最大限度地破坏了天然纤维的形态结构,主要是细胞壁的组织。後者的存在影响丝光化与黄酸化的反应     

Modification of isotactic polypropylene by a cold plasma or an electron beam and grafting of the acrylic acid onto these activated polymers

Surface grafting of polymeric materials, such as films and fibers, may improve their reactive surface properties. Polypropylene active sites that should initiate a surface postgrafting can be formed by either nitrogen cold plasma or an electron-beam irradiation. The plasmamodified polymer surface is cross-linked and functionalized with primary amino groups and with oxidized groups, and it is almost not degraded. Electron-beam-modified polypropylene is also functionalized through an aging reaction, emphasized by a high radical concentration. In both cases, active surface films are susceptible to react with monomers in a postgrafting reaction. The grafting yield and rate of acrylic acid were shown to be dependent on the formed amino group concentration: The hydrophilic character of the modified polypropylene surface enhances the acrylic acid approach. The electron-beam treatment leads also to a reactive surface that can initiate a grafting reaction. But its yield and rate are dependent on the radical concentration: radicals formed during the irradiation. © 1994 John Wiley & Sons, Inc.