丙烯酸酯和甲基丙烯酸酯基团转移共聚研究

研究了三种丙烯酸酯分别和四种甲基丙烯酸酯的基团转移共聚，用１Ｈ ＮＭＲ法测定共聚物组成，扩展的Ｋｅｌｅｎ Ｔｕｄｏｓ法测定竞聚率，结果为γＭＡ＝９２３、γＭＭＡ＝００６；γＥＡ＝１４１５、γＭＭＡ＝００１；γＢＡ＝７５１、γＭＭＡ＝００２；γＭＡ＝１４４１、γＥＭＡ＝００１；γＭＡ＝１３９６、γＢＭＡ＝０２３；γＭＡ＝８６６、γｉ ＢＭＡ＝００８，表明基团转移聚合同阴离子聚合有明显的相似之处．     

Neutral Pd(II) and Ni(II) acetylide complexes as single‐component initiators for polymerizations of butyl methacrylate and acrylates

Homogeneous polymerization of butyl methacrylate (BMA) using Pd(II)‐ and Ni(II)‐based acetylide complexes as single‐component initiators has been investigated in CHCl₃ at 60°C. M(PPh₃)₂(C = CR)₂ (M = Pd, Ni; R = Ph, CH₂OH, CH₂OOCCH₃) were found to be a novel type of effective initiators for the polymerization of butyl methacrylate. Among them, Pd(PPh₃)₂(C‐CPh)₂ (PPP) shows the highest activity. Besides, PPP alone can also initiate the homogeneous polymerizations of acrylates, e. g., methyl acrylate (MA), and n‐butyl acrylate (BA). The present type of polymerization is not hindered by the incorporation of hydroquinone.     

含疏水链节的聚N-异丙基丙烯酰胺共聚物的温敏性

采用溶液聚合法合成了一系列N-异丙基丙烯酰胺(NIPAM)与甲基丙烯酸甲酯、丙烯酸乙酯、丙烯酸丁酯或甲基丙烯酸丁酯的无规共聚物,用浊度观测法和光散射法测定了不同共聚物水溶液的温敏相转变行为.结果表明:所得共聚物的低临界溶解温度(LCST)均低于均聚物PNIPAM的,酯类单体的结构和含量对共聚物的LCST有显著影响,其中酯基上的烷基对共聚物LCST的影响能力大于丙烯酸酯α位上的烷基,前者对增大共聚物的疏水性有更大贡献.通过NIPAM与特定丙烯酸酯单体进行无规共聚可以合成转变温度低于PNIPAM均聚物且具有预设LCST数值的水溶性温敏聚合物.     

Degradation of poly(butyl methacrylate) model compounds studied via high‐resolution electrospray ionization mass spectrometry

This study investigates the degradation behavior of poly(n‐butyl methacrylate) ( p(nBMA) ), poly(tert‐butyl methacrylate) ( p(tBMA) ), and poly(hexafluoro butyl methacrylate) ( p(HFBMA) ) on a molecular level under extreme environmental conditions. The polymers chosen are readily applicable in the formulation of surface coatings and were degraded under conditions which replicated the harsh Australian climate, in which surface coatings may reach temperatures of up to 95 °C and are exposed to broad‐spectrum UV radiation of up to 1 kW m^?2. The degradation profiles were mapped with high‐resolution electrospray ionization mass spectrometry (ESI‐MS) with a LCQ quadrupole ion trap mass analyzer, with the peak assignments confirmed to within 3 ppm using ESI‐MS with a LTQ‐Orbitrap mass detector. It was found that in all the butyl ester polymers analyzed herein—regardless of their tertiary side‐chain structure—the loss of the butyl ester group and subsequent formation of acid side groups are a component of the overall degradation pathway of poly(butyl methacrylate)s under these harsh conditions. However, it is also demonstrated that the magnitude of this pathway is intimately linked to the side‐chain structure with the propensity for degradation decreasing in the order p(tBMA) > p(nBMA) > p(HFBMA) . The degradation mechanisms identified in this study, in combination with the previous end‐group degradation studies of poly(methyl methacrylate) and poly(n‐butyl acrylate), have allowed a much deeper understanding of the molecular degradation behavior of poly(acrylate)s and poly(methacrylate)s in an extreme natural environment. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Fluorinated and ring‐substituted bisbenzimidazole copper complexes for ethylene/acrylate copolymerization

Bisbenzimidazole copper dichloride complexes (CuBBIMs), when activated with methylaluminoxane, catalyze the random copolymerization of ethylene with acrylates to produce highly linear functional copolymers. To probe the sensitivity of the copolymerization to the catalyst structure, a series of CuBBIM catalysts with various steric, electronic, and geometric ligand characteristics was prepared, including CuBBIMs having benzimidazole ring substituents and ligand backbones of various lengths. Four different acrylates were also evaluated as comonomers (t‐butyl acrylate, methyl acrylate, t‐butyl methacrylate, and methyl methacrylate). Although no obvious ligand‐based influences on copolymerization were identified, the structure of the acrylate comonomer was found to exert significant effects. Copolymers prepared with t‐butyl methacrylate comonomer exhibited the highest ethylene contents (31–63%), whereas those prepared with methyl acrylate contained only minor amounts of ethylene (<15%). Copolymerizations carried out at lowered acrylate feed levels generally had increased ethylene contents but showed smaller yields, lowered molecular weights, and increased branching. Unusual ketoester structures were also observed in the methyl acrylate and methyl methacrylate containing copolymers, suggesting that the acrylate ester group size may be an important controlling factor for copolymerization. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1817–1840, 2006     

顶空气相色谱-质谱联用法测定胶粘剂中的残余单体

建立了一种测定胶黏剂中6种丙烯酸酯和甲基丙烯酸酯类残余单体的分析方法。样品经100 ℃、30 min顶空加热后,通过DB-WAX色谱柱(30 m×0.25 mm×0.25 μm)分离和质谱选择离子模式检测,内标法定量。结果表明,6种残余单体能达到良好的分离,检出限(信噪比为3)为0.069～0.096 mg/kg,定量限(信噪比为10)为0.23～0.32 mg/kg,平均回收率为96.0%～104.6%,相对标准偏差(RSD)小于7.2%。该方法操作简便、准确、重复性好、灵敏度高,可用于胶黏剂中丙烯酸酯和甲基丙烯酸酯类残余单体的快速测定。     

Synthesis of core-shell polymer microspheres by two-stage distillation-precipitation polymerization

Narrow- or monodisperse core-shell polymer microspheres with a dense core and a lightly crosslinked shell with different functional groups, such as ester, hydroxyl, cyano, were prepared by two-stage distillation-precipitation polymerization without any stabilizer. Commercial divinylbenzene (DVB), containing 80% of DVB was polymerized by distillation-precipitation polymerization with 2,2′-azobis(2-methyl propionitrile) (AIBN) as initiator in neat acetonitrile in the absence of any stabilizer as the first stage polymerization and used as the core. When the conversion of DVB was about 35% in the first stage, the second-comonomers with different functional groups, such as methyl methacrylate (MMA), ethyl methacrylate (EMA), butyl methacrylate (BMA), 2-hydroxyethyl methacrylate (HEMA), i-octyl acrylate (i-OA), dodecyl acrylate (DA), methyl acrylate (MA), ethyl acrylate (EA), ethylene glycol dimethacrylate (EGDMA), triethyleneglycol dimethacrylate (TEGDMA), trimethylolpropane trimethacrylate (Trim), and acrylnitrile (AN) together with AIBN were introduced, respectively, into the reaction system and copolymerized with unreacted DVB on the core surface to form a lightly crosslinked functional shell. The resulting core-shell polymer particles were characterized with scanning electron microscopy (SEM) and FT-IR spectra.     

甲基丙烯酸酯和丙烯酸酯基团转移共聚的竞聚率

甲基丙烯酸酯和丙烯酸酯基团转移共聚的竞聚率邹友思郭金全戴李宗潘容华（厦门大学化工系，厦门，３６１００５）基团转移聚合是制备极性单体的嵌段或无规共聚物的有效方法。如用甲基丙烯酸甲酯（ＭＭＡ）和丙烯酸丁酯（ＢＡ）进行嵌段共聚，可制得热塑性弹性体［１...     

Synthesis of acrylic rosin derivatives and application as negative photoresist

Functional monomers containing a rosin moiety, maleopimaric acid anhydride (MPA) and fumaropimaric acid (FPA) were synthesized from gum rosin. Monofunctional acrylic rosin derivatives were synthesized from esterification of MPA and various acrylates, (2-hydroxyethyl acrylate) (HEA), 3-hydroxypropyl acrylate, and 4-hydroxybutyl acrylate. Monofunctional monomers were copolymerized with (methyl methacrylate) (MMA) by radical polymerization. Trifunctional acrylate was synthesized from FPA and HEA. All the monomers and polymers showed good solubility and low absorbance in the UV region (200-400 nm). Negative patterns from rosin derivatives were obtained by two methods, one is a photocuring method using trifunctional acrylate and copolymers, and the other is photocrosslinking of copolymers using a photocrosslinker under UV (I-line) radiation. Negative photoresists containing rosin moiety showed high contrast and minimum linewidth of 2.2 μm.     

Novel copolymers via nitroxide mediated controlled free radical polymerization of vinyl chloride

Controlled free radical polymerization (CFRP) of vinyl chloride (VCM) and copolymerization with several comonomers have been studied in aqueous suspension. Therefore di-tert-butylnitroxide and three novel nitroxyl radicals were used as mediating agents. Copolymerization of VCM with styrene, partly combined with acrylonitrile, maleic acid anhydride and maleic acid imide as well as methyl methacrylate, n-butyl methacrylate, butyl acrylate and butadiene have been achieved, demonstrating an efficient route for novel vinyl chloride copolymer architecture.     

Thermal degradation of butyl acrylate-methyl acrylate-acrylic acid-copolymers

The thermal degradation of copolymers based on butyl acrylate-methyl acrylate-acrylic acid used as acrylic pressure-sensitive adhesives, especially for bonding of plasticizer containing materials, has been investigated using thermogravimetry and pyrolysis-gas chromatography at 250°C. It was observed that during the pyrolysis of butyl acrylate-methyl acrylate-acrylic acid copolymers unsaturated monomers as methyl acrylate, methyl methacrylate, butyl acrylate and butyl methacrylate were formed. During the side-chain butyl acrylate-methyl-acrylate-acrylic acid-copolymer degradation the presence of methyl alcohol and butyl alcohol was observed.     

Atom‐Transfer Radical Polymerization of Acrylates in an Ionic Liquid

The atom‐transfer radical polymerization (ATRP) of acrylates in 1‐butyl‐3‐methylimidazolium hexafluorophosphate was investigated. The solubility of the acrylates in the ionic liquid depends on the substituent. The homogeneous polymerization of methyl acrylate gives polymers with M̄_n close to the calculated value and relatively narrow polydispersity. In heterogeneous polymerizations of higher acrylates, with the catalyst present in the ionic liquid phase, deviations from ideal behavior are observed although the polymerization of butyl acrylate approaches the conditions of a controlled polymerization.     

丙烯腈和(甲基)丙烯酸酯基团转移共聚合的竞聚率

研究了丙烯腈（ＡＮ）和甲基丙烯酸甲酯（ＭＭＡ）、乙酯（ＥＭＡ）、丁酯（ＢＭＡ）、丙烯酸丁酯（ＢＡ）和顺丁烯二酸二丁酯（ＤＢＭ）等５种酯类单体的基团转移无规共聚．用Ｋｅｌｅｎ Ｔｕｄｕｓ法测定了二元共聚体系的竞聚率，分别为ｒＡＮ＝１０２２、ｒＭＭＡ＝０７７、ｒＡＮ＝５６８、ｒＥＭＡ＝０１６、ｒＡＮ＝８５９、ｒＢＭＡ＝００９、ｒＡＮ＝４０８、ｒＢＡ＝００６；ｒＡＮ＝１３８，ｒＤＢＭ＝００６．发现竞聚率，单体组分对聚合速率的影响等都和阴离子共聚类似．     

Preparation and application of the sol-gel-derived acrylate/silicone co-polymer coatings for headspace solid-phase microextraction of 2-chloroethyl ethyl sulfide in soil

Three types of novel acrylate/silicone co-polymer coatings, including co-poly(methyl acrylate/hydroxy-terminated silicone oil) (MA/OH-TSO), co-poly(methyl methacrylate/OH-TSO) (MMA/OH-TSO) and co-poly(butyl methacrylate/OH-TSO) (BMA/OH-TSO), were prepared for the first time by sol-gel method and cross-linking technology and subsequently applied to headspace solid-phase microextraction (HS-SPME) of 2-chloroethyl ethyl sulfide (CEES), a surrogate of mustard, in soil. The underlying mechanisms of the coating process were discussed and confirmed by IR spectra. The selectivity of the three types of sol-gel-derived acrylate/silicone coated fibers was studied, and the BMA/OH-TSO coated fibers exhibited the highest extraction ability to CEES. The concentration of BMA and OH-TSO in sol solution was optimized, and the BMA/OH-TSO (3:1)-coated fibers possessed the highest extraction efficiency. Compared with commercially available polyacrylate (PA) fiber, the sol-gel-derived BMA/OH-TSO (3:1) fibers showed much higher extraction efficiency to CEES. Therefore, the BMA/OH-TSO (3:1)-coated fibers were chosen for the analysis of CEES in soil matrix. The reproducibility of coating preparation was satisfactory, with the RSD 2.39% within batch and 3.52% between batches, respectively. The coatings proved to be quite stable at high temperature (to 350 degrees C) and in different solvents (organic or inorganic), thus their lifetimes (to 150 times) are longer than conventional fibers. Extraction parameters, such as the volume of water added to the soil, extraction temperature and time, and the ionic strength were optimized. The linearity was from 0.1 to 10 microg/g, the limit of detection (LOD) was 2.7 ng/g, and the RSD was 2.19%. The recovery of CEES was 88.06% in agriculture soil, 92.61% in red clay, and 101.95% in sandy soil, respectively.     

用双硫酯链转移法合成嵌段聚合物

研究了以双硫酯为链转移剂进行的均聚和嵌段共聚物的合成 .首先合成大分子链转移剂 ,得到分子量可控、多分散性系数较小的均聚物PMMA、PBMA、PEMA、PEA、PBA、PMA、PSt,多分散性系数一般小于 1 30 .在相同的条件下 ,甲基丙烯酸酯类的聚合速度最快 ,苯乙烯其次 ,丙烯酸酯类最慢 .用末端带有双硫酯基团的PSt、PBMA、PBA为链转移剂 ,加入多种第二单体聚合得到实测分子量与理论分子量接近 ,且多分散性系数较小的两嵌段聚合物 .在链转移剂和引发剂的比例为 3∶1～ 6∶1的范围内 ,聚苯乙烯同样可以作为第一嵌段得到和其它酯类单体的两嵌段聚合物 .1 H NMR方法证明了聚合物的末端带有双硫酯基团 .嵌段聚合时必须加入微量的自由基引发剂以形成大分子自由基 ,达到较好的控制聚合效果     

Improved heat resistance in poly (lactic acid)/ethylene butyl methacrylate glycidyl methacrylate terpolymer blends by controlling highly filled talc particles

Journal of Thermal Analysis and Calorimetry - Heat resistance poly(lactic acid) PLA/ethylene butyl methacrylate glycidyl methacrylate terpolymer (GEBMA)/talc composites were fabricated by melt...     

无皂高分子纳米胶乳粒子的制备与稳定

在微波辐照下,以过硫酸钾(KPS)为引发剂,丙酮水溶液(质量比1∶ 1)为分散介质,进行了苯乙烯(ST)和其它共聚单体:甲基丙烯酸甲酯(MMA)、甲基丙烯酸丁酯(BMA)、丙烯酸乙酯(EA)及顺丁烯二酸酐(BDA)的无皂乳液聚合,得到了稳定的纳米胶乳粒子.讨论了共聚单体的种类和浓度对粒子水化半径的影响.增加配方中亲水性单体含量,使引发反应中引发剂的消耗量增加,粒子表面电荷密度增大,同时亲水性增加,油水界面张力减小,粒子变得稳定,有利于小粒子的生成.粒子的大小随亲水性单体的含量呈曲线关系,曲线上有最低点.     

New initiator system for the anionic polymerization of (meth)acrylates in toluene. IV. Random copolymerization of (meth)acrylates in toluene initiated by s-BuLi ligated by lithium silanolates

Copolymerization of binary mixtures of alkyl (meth)acrylates has been initiated in toluene by a mixed complex of lithium silanolate  (s-BuMe₂SiOLi) and s-BuLi (molar ratio > 21) formed in situ by reaction of s-BuLi with hexamethylcyclotrisiloxane (D₃). Fully acrylate and methacrylate copolymers, i.e., poly(methyl acrylate-co-n-butyl acrylate), poly(methyl methacrylate-co-ethyl methacrylate), poly(methyl methacrylate-co-n-butyl methacrylate), poly(methyl methacrylate-co-n-butyl methacrylate), poly(isobornyl methacrylate-co-n-butyl methacrylate), poly(isobornyl methacrylate-co-n-butyl methacrylate) of a rather narrow molecular weight distribution have been synthesized. However, copolymerization of alkyl acrylate and methyl methacrylate pairs has completely failed, leading to the selective formation of homopoly(acrylate). As result of the isotactic stereoregulation of the alkyl methacrylate polymerization by the s-BuLi/s-BuMe₂SiOLi initiator, highly isotactic random and block copolymers of (alkyl) methacrylates have been prepared and their thermal behavior analyzed. The structure of isotactic poly(ethyl methacrylate-co-methyl methacrylate) copolymers has been analyzed in more detail by Nuclear Magnetic Resonance (NMR). © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2525–2535, 1999     

Amphiphilic copolymers with poly(meth)acrylic acid chains “grafted from” caprolactone 2‐(methacryloyloxy)ethyl ester‐based backbone

Well‐defined amphiphilic graft copolymers containing hydrophilic poly((meth)acrylic acid) (PMAA) or poly(acrylic acid) (PAA) side chains with gradient and statistical distributions were synthesized. For this purpose, the hydroxy‐functionalized copolymers with various gradient degrees, in which 2‐(6‐hydroxyhexanoyloxy)ethyl (meth)acrylate units (caprolactone 2‐[methacryloyloxy]ethyl ester, CLMA) formed strong gradient with tert‐butyl acrylate (tBA), slight gradient copolymers with tert‐butyl (meth)acrylate (tBMA), and statistical copolymers with methyl (meth)acrylate (MMA) were modified to bromoester multifunctional macroinitiators, P(tBMA‐grad‐BrCLMA), P(BrCLMA‐grad‐tBA), and P(BrCLMA‐co‐MMA). In the next step, they were applied in controlled radical polymerization of tBMA and tBA yielding graft copolymers with various lengths of side chains as well as graft densities. Further, the tert‐butyl groups in copolymers were successfully removed via acidolysis in the presence of trifluoracetic acid, which caused transformation of the hydrophobic graft copolymers into amphiphilic ones with ability of self‐assembly for the future biomedical applications. Copyright © 2013 John Wiley & Sons, Ltd.     

Synthesis and characterization of amphiphilic heterograft copolymers with PAA and PS side chains via “Grafting from” approach

The amphiphilic heterograft copolymers poly(methyl methacrylate‐co‐2‐(2‐bromoisobutyryloxy)ethyl methacrylate)‐graft‐(poly(acrylic acid)/polystyrene) (P(MMA‐co‐BIEM)‐g‐(PAA/PS)) were synthesized successfully by the combination of single electron transfer‐living radical polymerization (SET‐LRP), single electron transfer‐nitroxide radical coupling (SET‐NRC), atom transfer radical polymerization (ATRP), and nitroxide‐mediated polymerization (NMP) via the “grafting from” approach. First, the linear polymer backbones poly(methyl methacrylate‐co‐2‐(2‐bromoisobutyryloxy)ethyl methacrylate) (P(MMA‐co‐BIEM)) were prepared by ATRP of methyl methacrylate (MMA) and 2‐hydroxyethyl methacrylate (HEMA) and subsequent esterification of the hydroxyl groups of the HEMA units with 2‐bromoisobutyryl bromide. Then the graft copolymers poly(methyl methacrylate‐co‐2‐(2‐bromoisobutyryloxy)ethyl methacrylate)‐graft‐poly(t‐butyl acrylate) (P(MMA‐co‐BIEM)‐g‐PtBA) were prepared by SET‐LRP of t‐butyl acrylate (tBA) at room temperature in the presence of 2,2,6,6‐tetramethylpiperidin‐1‐yloxyl (TEMPO), where the capping efficiency of TEMPO was so high that nearly every TEMPO trapped one polymer radicals formed by SET. Finally, the formed alkoxyamines via SET‐NRC in the main chain were used to initiate NMP of styrene and following selectively cleavage of t‐butyl esters of the PtBA side chains afforded the amphiphilic heterograft copolymers poly(methyl methacrylate‐co‐2‐(2‐bromoisobutyryloxy)ethyl methacrylate)‐graft‐(poly(t‐butyl acrylate)/polystyrene) (P(MMA‐co–BIEM)‐g‐(PtBA/PS)). The self‐assembly behaviors of the amphiphilic heterograft copolymers P(MMA‐co–BIEM)‐g‐(PAA/PS) in aqueous solution were investigated by AFM and DLS, and the results demonstrated that the morphologies of the formed micelles were dependent on the grafting density. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011