高盐沙地固沙用阴离子型P(VAc-DBM-AN)乳液生态固沙性能的研究

采用种子乳液聚合法,以醋酸乙烯酯(VAc)、马来酸二丁酯(DBM)、丙烯腈(AN)为共聚单体,制备了P(VAc-DBM-AN)三元共聚阴离子型乳液,并首次将其用于高盐沙地固沙。详细考察了P(VAc-DBM-AN)共聚乳液用于高盐沙地固沙时,其固沙强度、耐热老化,保水性及生态效应。结果表明,相比于P(VAc-DBM)共聚乳液而言,通过AN功能单体的引入,阴离子型P(VAc-DBM-AN)乳液具有更高的固沙强度和优异的抗热老化及冻融稳定性,且具有良好的生态效益。     

IA/ASP/AMPS三元共聚物合成及阻垢性能

以衣康酸(IA)、天冬氨酸(ASP)和2-丙烯酰胺-2-甲基丙磺酸(AMPS)为单体,在过硫酸铵引发下采用水溶液自由基聚合方法制备了新型IA/ASP/AMPS三元共聚物阻垢剂,并利用红外光谱仪对其结构进行分析表征。通过正交实验和单因素实验考察单体摩尔配比、引发剂用量、反应温度及反应时间对共聚产物阻垢性能的影响,确定其最佳合成条件。实验结果表明:共聚单体的摩尔比nIA:nASP:nAMPS为3:1:0. 5,引发剂用量占单体总质量的10%,反应温度为85℃,反应时间为4 h时,合成三元共聚物对碳酸钙、硫酸钙及磷酸钙的阻垢性能最好,阻垢率分别达91%、95%及96%以上;此共聚物的固含量和黏均相对分子质量分别为30. 5%、1402。静态阻垢法评价温度对IA/ASP/AMPS共聚物阻垢性能的影响,结果表明,IA/ASP/AMPS共聚物适用于含碳酸钙、磷酸钙的高温循环冷却水体系。     

蒽醌型蓝色扩链剂及其PUA共聚物乳液的制备与性能

首先以1-甲氨基-4-溴-蒽醌和2-氨基-2-甲基-1,3-丙二醇为原料,通过取代反应合成了蒽醌型蓝色扩链剂1-(1,1-二(羟甲基))乙氨基-4-甲氨基蒽醌(HMEMAQ),并将其与N,N-二(2-羟乙基)丙烯酰胺作为扩链剂合成出聚氨酯预聚体,然后经与甲基丙烯酸甲酯和丙烯酸丁酯的接枝乳液共聚合制备出了性能稳定的共聚型蓝色聚氨酯-丙烯酸酯共聚物(PUA)乳液.然后用1H-NMR、FTIR、UV-Vis吸收光谱、粒度和电位分析、氙灯老化等方法对HMEMAQ的化学结构、PUA乳液及乳胶膜的性能进行了表征.研究发现,在N2气氛下,用偶氮类AIBN作为引发剂可以有效避免PUA乳液合成过程中生色基团的氧化变色现象.当AIBN用量达到不饱和单体的2 wt%时,接枝反应的单体转化率可达到99.9%.HMEMAQ用量对乳液的胶体性质和单体转化率没有明显影响.PUA聚合物和HMEMAQ的UV-Vis吸收光谱保持一致,最大吸收波长均为640.8 nm.与具有相同生色基团的共混型蓝色PUA乳胶膜相比,共聚型PUA乳胶膜的耐光色牢度和耐溶剂色牢度有明显的提高.     

高固含量低粘度丙烯酸酯乳液压敏胶的制备

采用常规种子乳液聚合法合成出了固含量为65%、粘度小于400mPa·s的乳液压敏胶,研究了共聚单体、乳化剂、引发剂、缓冲剂及种子乳液量对丙烯酸酯共聚物乳液粘度和聚合稳定性的影响。结果表明:含羧基和羟基的功能单体对乳液的粘度和聚合稳定性影响较大;乳液压敏胶粘度随乳化剂量在预乳化液中所占比例增大及种子乳液量的增大而增大,随引发剂过硫酸铵(APS)用量增大而降低,随缓冲剂碳酸氢钠在预乳化液中所占比例增大先增大后减小;乳液压敏胶的聚合凝胶率随乳化剂量在预乳化液中所占比例增大及种子乳液量降低而减小,当APS为单体量的0.3%,NaHCO3在预乳化液和反应中的比例为2/4时,乳液凝胶率最低。     

离子型表面活性单体存在下的MMA/BA乳液聚合(Ⅰ)——表面活性单体的合成及其(共)聚合活性

合成了两种离子型表面活性单体(Surfmer)磺化-十二醇-烯丙基甘油-丁二酸酯钠盐(ZC-L)和磺化-十二醇-甲基丙烯酰甘油-丁二酸酯钠盐(ZD-L).着重研究了ZC-L的结构、表面张力行为、均聚及共聚能力.实验结果表明,不同Surfmer用量以及不同固含量下,MMA/BA/Surfmer,MMA/Surfmer及BA/Surfmer共聚乳液的表面张力较高,说明Surfmer已通过共聚结合在乳胶粒上,乳液中残留甚少.对MMA/BA体系,ZC-L的共聚性能比ZD-L好.     

P(AMPS-co-HEMA)凝胶的合成与吸银性能研究

以2-丙烯酰胺基-2-甲基丙磺酸(AMPS)和甲基丙烯酸羟乙酯(HEMA)为单体,N,N′-亚甲基双丙烯酰胺(MBA)为交联剂,过硫酸钾(KPS)为引发剂,采用自由基水溶液聚合法制备P(AMPS-co-HEMA)共聚凝胶,通过傅里叶红外光谱(FT-IR)对材料结构进行了表征.研究单体配比、交联剂的用量、引发剂的用量对共聚凝胶吸水性能的影响,并在此基础上对凝胶的溶胀、吸银及消溶胀性能进行研究.结果表明,当单体摩尔比n(AMPS)∶n(HEMA)=2∶1,交联剂用量ω(MBA)=0.6％,引发剂用量ω(KPS)=0.8％,所制得的凝胶吸水性能最好;凝胶在蒸馏水中的溶胀过程属于松弛平衡扩散;凝胶在AgNO3溶液中60min左右达到消溶胀平衡,且当AgNO3溶液的浓度为0.05mol/L时,银离子吸附量最大,为0.04g/g,消溶胀速率最快.     

乳胶附聚型阴离子交换固定相的制备及表征

以烯丙基缩水甘油醚（AGE）为乳胶聚合单体,制备了一种乳胶附聚型阴离子交换固定相。通过无皂化乳液聚合法,以AGE和苯乙烯（ST）为共聚单体制备AGE-ST共聚乳胶。将该乳胶季铵化后附聚在磺化的聚苯乙烯-二乙烯苯（PS-DVB）微球表面,制备一种乳胶附聚型阴离子交换色谱固定相。通过扫描电镜（SEM）、傅里叶红外光谱（FT-IR）和元素分析（EA）等对该乳胶附聚型阴离子交换色谱固定相的理化性质进行表征,结果显示季铵化的AGE-ST共聚乳胶成功附聚在磺化的PS-DVB微球表面,并通过分离常规阴离子和有机酸对制得的阴离子交换剂的色谱性能进行评价。AGE以其良好的pH耐受性和活泼的反应活性为离子交换色谱固定相的制备提供一个新的选择。     

乙烯气相法制醋酸乙烯钯金催化剂的研究进展

醋酸乙烯(Vinyl Acetate VAc)又称醋酸乙烯酯,是世界上用量最大的有机化工原料之一,广泛用于生产聚醋酸乙烯乳液与树脂(PVAc)、聚乙烯醇(PVA)、乙烯-醋酸乙烯共聚乳液(VAE)、氯乙烯-醋酸乙烯共聚物(EVC)、聚丙烯腈共聚单体以及缩醛树脂等衍生物,在涂料、浆料、粘合剂、维     

新型可聚合蒽醌染料单体及其共聚物乳液的制备及性能

通过多步有机反应合成了新型蒽醌染料单体1-(间(2-(2-(丙烯酰氧基)乙氧基)乙基砜基)苯胺基)蒽醌(AVSAQ),对其化学结构进行了表征;然后将其与苯乙烯(St)、丙烯酸丁酯(BA)和甲基丙烯酸(MAA)进行半连续乳液共聚合,制备出了共价键合型P(St-BA-MAA-AVSAQ)橙红色聚合物乳液,并对乳液以及乳胶膜的性能进行了表征,系统考察了AVSAQ和过硫酸铵(APS)用量对单体总转化率以及乳液胶体性质的影响.结果表明,当AVSAQ用量不高于单体总量的4.0 wt%、APS用量不低于单体总量的0.5 wt%时,聚合反应可以平稳进行,所得乳胶粒水合粒径均在60 nm左右.总单体转化率和AVSAQ转化率随着AVSAQ用量的增加而降低,当AVSAQ用量达到4.0 wt%时,二者分别为95.0%和93.6%.P(St-BA-MAA-AVSAQ)的UV-Vis吸收光谱特性与AVSAQ完全一致,最大吸收波长均为486.8 nm.与相应非共价键合型橙红色聚合物乳液相比,P(StBA-MAA-AVSAQ)聚合物乳液具有良好的储存稳定性和保色性,乳胶膜的光色牢度和耐溶剂牢度也显著提高.     

含氟共聚乳液改善浸渍滤纸抗水抗油性的研究

用核/壳乳液聚合工艺,通过改变单体组成、设计乳胶粒子的形态结构和在乳胶粒子的壳层中引入含氟丙烯酸酯单体,制备具有核/壳结构的含氟丙烯酸酯的共聚乳液。并通过FTIR1、3C-NMR、TEM等手段对共聚乳液的化学结构以及乳胶粒子形态结构进行了表征。同时研究了含氟单体种类和用量、乳化剂种类以及单体加料方式对其聚乳液性能以及浸渍滤纸抗水/油性的影响。     

AMPS/MMA二元共聚微球的超声无皂乳液制备与表征

将超声辐射无皂乳液聚合作用于含有2-丙烯酰胺基-2-甲基丙磺酸（AMPS）和甲基丙烯酸甲酯（MMA）的水溶液中,在不加任何引发剂和乳化剂的条件下合成AMPS/MMA二元共聚高分子微球,考察了超声反应时间对单体转化率的影响,用FTIR、TGA-DSC、TEM和粒度分析仪等技术进行了表征,并初步探讨了聚合反应机理。结果表明,合成得到的高分子微球粒径在0.77μm左右,分散均匀,且具有较好的热稳定性     

A novel route to prepare highly surface active nanogel particles based on nonaqueous emulsion polymerization

The motivation of the current work has stemmed from the fact that the selection of suitable stabilizers for nonaqueous emulsions is still challenging because of lack of general knowledge about the underlying stabilization mechanisms. The preparation and surface activity of new amphiphilic gel nanoparticles in organic solvents were investigated. A new bifunctional surfmer was prepared by reacting polyoxyethylene 4‐nonyl‐2‐propylene‐phenol nonionic reactive surfactant with maleic anhydride followed by esterification with poly(ethylene glycol). This surfmer was used as stabilizer to prepare amphiphilic crosslinked N‐isopropylacrylamide (NIPAm) and 2‐acrylamido‐2‐methylpropane sulfonic acid (AMPS) copolymer nanogel on the basis of nonaqueous radical copolymerization temperature modified method in the presence of toluene and formamide (FA) as solvents and N, N‐methylene bisacrylamide as a crosslinker. The chemical structure of the prepared nanogels was determined by Fourier transform infrared spectroscopy analyses. The morphologies of the prepared nanogels were detected by transmission electron microscopy and scanning electron microscopy techniques. The surface tension of colloidal NIPAm/AMPS dispersions was measured in FA as functions of surface age (time), temperature, and the morphology of the NIPAm/AMPS nanogels. The NIPAm/AMPS nanogels reduced the surface tension of FA from 58.2 to about 30.2 mN/m at 25°C, and a little increase in the surface tension was observed at 40°C. The prepared nanogels show great reduction in interfacial tension values between FA and styrene. The NIPAm/AMPS dispersions exhibited high surface activity and used as stabilizers to prepare crosslinked styrene‐co‐AMPS microgel in the presence of divinylbenzene and FA as organic solvents based on nonaqueous emulsion crosslinking polymerization technique. Copyright © 2013 John Wiley & Sons, Ltd.     

微米级单分散共聚物微球的制备

用分散聚合法制备了苯乙烯 甲基丙烯酸甲酯微米级单分散共聚物微球 ,粒径为 5 4 μm .将分散聚合体系与乳液聚合体系进行了比较 ,并对共聚物微球的形貌、粒径分布及共聚情况进行了表征研究 .     

Noncovalent modification of self-assembled functionalized COF by PNIPAM and its properties of Pickering emulsion

Based on a facile and universal method using noncovalent bonding, here, polymer-modified covalent organic framework materials (COFs) were rapidly prepared. PNIPAM-modified COF (COF-PNIPAM) was synthesized by electrostatic self-assembly between COF prepared by low-cost melamine and terephthalaldehyde and carboxyl-terminated poly(N-isopropylacrylamide) (PNIPAM) prepared via reversible addition-fragmentation chain transfer polymerization. The carboxyl-terminated PNIPAM was characterized by Gel Permeation Chromatography and Ultraviolet and Visible Spectroscopy (UV–vis). COF and COF-PNIPAM were characterized by Fourier Transform Infrared Spectroscopes, Scanning Electron Microscope, Transmission Electron Microscope, X-Ray Diffractomer (XRD), and Brunner-Emmet-Teller (BET) measurements. The results showed that the COF-PNIPAM was successfully prepared. The Pickering emulsion properties of the COF-PNIPAM in a water-to-toluene mixed system were studied, and when the water-to-oil ratio is 2:1, a stable emulsion can be obtained. However, the results show that the PNIPAM chains of COF-PNIPAM nearly lose their temperature responsiveness.     

Temperature and pH sensitive ionic hydrogels based on new crosslinkers

New crosslinkers were synthesized from reaction of melamine with acryloyl and methacryloyl chloride in the presence of 1‐methyl‐2‐pyrrolidone as a solvent and triethyl amine as acid acceptor. The chemical structures of the prepared crosslinkers were elucidated from FT‐IR, ¹H‐NMR and ¹³C‐NMR analyses. Linear 2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid and methacrylic acid (AMPS/MAA) copolymers were prepared and their viscometric properties in aqueous solution were investigated. Different weight percentages of the prepared crosslinkers were used as crosslinking agent (AMPS/MAA) to prepare ionic copolymers using ammonium persulfate as initiator. The percentage of crosslinkers was varied from 0.5 to 4 wt%. The swelling behaviors of crosslinked AMPS/MAA gels in deionized water were measured at different pH and temperatures. All AMPS/MAA copolymers exhibit faster deswelling rate at 50°C except for the copolymer containing 0.9 (mol ratio) AMPS. Copyright © 2005 John Wiley & Sons, Ltd.     

Studies on the Preparation of Stable and High Solid Content Emulsifier-Free Poly(MMA/BA/HEA) Latex with the Addition of AMPS and Characterization of the Obtained Copolymers

The 2-acrylamido -2-methylpropane sulfonic acid (AMPS) was used as a reactive comonomer for the methyl methacrylate (MMA), n-butyl acrylate (BA) and 2-hydroxyethyl acrylate (HEA) emulsifier-free emulsion copolymerization system to obtain latices of stable and high-solid content (50 wt%).The polymerization and storage process is very stable, and the emulsion could store at room temperature for more than six months with the addition of AMPS. Properties of the latices, such as stability, flow behavior, particles diameter and morphology were studied. In addition, physical properties of the obtained copolymers, such as water resistance, glass transition temperature (T_g) were also investigated. The final size of the latex particles is 200～300 nm in diameter. Compared with the copolymers that were prepared by surfactant emulsion polymerization water resistance is greatly improved.     

Adsorption of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and related compounds onto montmorillonite clay

Sodium montmorillonite clay (Na-MMT) was modified using 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS). The objective of this study was to determine which chemical group is the 'driving force' leading to the adsorption of AMPS inside the clay galleries. AMPS has been reported to be a good candidate as a clay modifier for the preparation of polymer-clay nanocomposites by in situ free radical polymerization in emulsion. However, the way in which AMPS interacts with the surface of MMT has not yet been studied. The type of interaction between organic modifiers and clay plays a determining role in the successful preparation of polymer-clay nanocomposite materials. The adsorption ability of three other organic compounds similar to AMPS, namely sodium 1-allyloxy-2-hydroxypropyl sulfonate (Cops), N-isopropylacrylamide (NIPA) and methacryloyloxyundecan-1-yl sulfate (MET), was also evaluated. These selected compounds also have functional groups potentially able to interact with the clay surface (i.e., a sulfonate group, an amido group, or a sulfate group, respectively). Results of FT-IR, TGA and SAXS analyses showed that AMPS, NIPA, Cops and MET all interacted with clay, but to various extents.     

Molecularly imprinted polymer membranes for substance-selective solid-phase extraction from water by surface photo-grafting polymerization

Hydrophilized polyvinylidene fluoride microfiltration membranes were surface-modified in the presence of a template (terbumeton) in methanol with a graft copolymer of a functional monomer (2-acrylamido-2-methyl-1-propane sulfonic acid, AMPS, methacrylic acid, MAA, or acrylic acid, AA) and a cross-linker (N,N'-methylene-bis-acrylamide) using UV irradiation and benzophenone as photoinitiator. As result, membranes covered with a thin layer of imprinted polymer selective to terbumeton were obtained. Blank membranes were prepared with the same monomer composition, but in the absence of the template. The membranes' capacity to adsorb terbumetone from aqueous solution was evaluated yielding information regarding the effect of polymer synthesis (type and concentration of functional monomer, concentration of cross-linker) on the resulting membranes' recognition properties. UV spectroscopic studies of the interactions with terbumetone revealed that AMPS forms a stronger complex than MAA and AA. In agreement with that finding, imprinting with AMPS gave higher affinities than with MAA and AA. The terbumeton-imprinted membranes showed significantly higher sorption capability to this herbicide than to similar compounds (atrazine, desmetryn, metribuzine). With the novel surface modification technology, the low non-specific binding properties of the hydrophilized microfiltration membrane could successfully be combined with the receptor properties of molecular imprints, yielding substance-specific molecularly imprinted polymer composite membranes. The high affinity of these synthetic affinity membranes to triazine herbicides together with their straightforward and inexpensive preparation provides a good basis for the development of applications of imprinted polymers in separation processes such as solid-phase extraction.     

无皂乳液聚合制备含铕荧光共聚物乳液的研究及其表征

以丙烯酸(AA)为第一配体、邻菲罗啉(Phen)为第二配体、Eu3+为中心离子,合成了一种可聚合的稀土铕配合物.以配合物单体、甲基丙烯酸甲酯、丙烯酰胺和对苯乙烯磺酸钠为共聚单体,通过无皂乳液聚合的方法,制备了含铕荧光共聚物乳液.采用红外光谱对共聚物的结构进行了表征,并探讨了配合物单体含量对共聚物乳液性能的影响.透射电子显微镜(TEM)和激光光散射粒度仪(PCS)测试结果表明,共聚物乳液形成了相对均一的球状结构,但随着配合物单体含量增加,共聚物微球粒径逐渐增大、分散性变差.采用荧光分光光度计测试了共聚物乳液的荧光性能,在594和619 nm处出现Eu3+的特征发射光谱,且荧光强度随着配合物单体含量增加而增强.     

Synthesis of amphiphilic tri-block copolymerpoly(vinylpyrrolidone)-b-poly(methyl methacrylate)-b-poly(vinylpyrrolidone) for the modification of polyethersulfone membrane

Well-defined amphiphilic tri-block copolymer PVP-b-PMMA-b-PVP was prepared for the first time via successive reversible addition fragmentation chain transfer(RAFT) polymerization using carboxyl-terminated trithiocarbonate as the RAFT agent.The structure of the copolymer was characterized using FTIR,GPC and ~1H NMR.The block copolymer could be directly blended with polyethersulfone(PES) as a macromolecule additive using N-methyl-2-pyrrolidone(NMP) as the solvent to prepare membranes. The water contact angles for the modified membranes decreased obviously,and therefore,the protein adsorption amount on the membrane surface decreased.