Hydrophobically modified poly[(divinyl ether)‐co‐(maleic anhydride)]: interactions with cyclodextrin derivatives and hydrogel formation

Hydrolyzed cyclocopolymer prepared from divinyl ether and maleic anhydride, poly[(divinyl ether)‐ co ‐(maleic anhydride)] (DIVEMA), was functionalized with aminoadamantane and subsequently compared with the hydrolyzed DIVEMA with respect to physicochemical properties. The complexation behavior of adamantyl modified DIVEMA with cyclodextrin derivatives was examined by dynamic light scattering, nuclear magnetic resonance spectroscopy and zeta potential. The scattering studies indicated the formation of well‐defined aggregated structures with an average diameter of 120 nm. These aggregated structures collapsed on addition of randomly methylated β‐cyclodextrin to give 4.2 nm in hydrodynamic diameter. Interactions with crosslinked β‐cyclodextrins indicated gel formation which was analyzed by means of rheology and temperature‐dependent viscosity showing disaggregation of the host‐guest system at 42 °C. This novel physical hydrogel is very interesting for medical applications as a drug delivery system with included anti‐tumor activity. Copyright © 2012 Society of Chemical Industry     

甲基乙烯基醚/马来酸酐共聚物合成研究

以过氧化十二酰为引发剂(IN),采用溶液自由基共聚合方法,实现了甲基乙烯基醚(MVE)与马来酸酐(MAN)的交替共聚合。通过详细研究反应温度、引发剂用量、溶剂配比、溶剂用量及反应时间等因素对共聚物产率及产品特性粘度的影响,优化了制备甲基乙烯基醚/马来酸酐共聚物的工艺条件。最后通过FTIR和13CNMR表征了共聚物的结构。     

一种梳状表面活性剂的合成及应用

以β-蒎烯/马来酸酐共聚物为主链,接枝聚乙二醇单甲醚,合成一种梳状高分子表面活性剂,并对产物进行了表征。讨论了反应物相对分子质量、反应物配比及反应时间对表面张力的影响,采用相反转乳化技术将其应用于松香酯乳液。结果表明,产物具有良好的表面活性,采用相对分子质量为6 300的β-蒎烯/马来酸酐共聚物为主链,接枝聚乙二醇单甲醚-500,2种反应物按照酸酐与羟基的摩尔比为1∶1进行反应,反应时间为12~16 h时,反应产物降低水溶液表面张力的效果最好,产物制备松香酯乳液效果良好。     

Metal-containing initiator systems

Summary The polymerization of vinyl monomers with the initiator systems of ferrocene and acid anhydrides were investigated. The initiator activity for radical polymerization of methyl methacrylate (MMA) was higher than that for styrene (St). However, isobutyl vinyl ether was not polymerized. The rate of polymerization of MMA with ferrocene/benzoic anhydride system was in proportional to the square root concentrations of both compounds of the initiator system, indicating the mechanism of radical polymerization. When an alternating copolymer of ethylene with maleic anhydride was used as an acid anhydride, a graft copolymer, which was soluble in dimethylformamide and tetrahydrofuran, was produced from radical polymerization of MMA.     

The Influence of the compatibilizer Characteristics on the interfacial characteristics and phase morphology of aPA/SAN blends

The main objective of this work is study the influence of the methyl mathacrylate maleic anhydride copolymer (MMA-MA) compatibilizer properties such as molecular weight and maleic anhydride content in the characteristics of amorphous polyamide and styrene acrylonitrile copolymer (aPA/SAN) blends, correlating their interfacial characteristics and phase morphology. The blends aPA/SAN, with and without the compatibilizer, prepared were characterized by transmission electron microscopy (TEM) and small angle X-rays scattering (SAXS). The results show that the maleic anhydride concentration has a more significant effect on the blend properties than the molecular weight of the MMA-MA copolymer. Even though the system aPA/SAN is thermodynamically immiscible, it shows morphology of phases with small particles of SAN. The addition of MMA-MA copolymer with high degrees of MA led to an increase of the SAN phase particle size. With SAXS technique, it was possible to determine the interface thickness and the results shows that the characteristics of the interface do not change with the variation of the compatibilizer characteristics. The results observed in this work indicate that the viscosity ratio is very important factor on the formation of the phase morphology.     

Grafting of Maleic Anhydride Copolymers onto Cellulose Acetate and Methyl Cellulose

A high level of control over grafting reactions onto cellulose derivatives was achieved by an acyl transfer reaction mechanism. Ethylene/maleic anhydride copolymer (EMA) and styrene/maleic anhydride copolymer (SMA) were grafted onto cellulose acetate (CA) and methyl cellulose (MC) in a simple and effective way under homogeneous reaction conditions. While pyridine, a commonly used catalyst for the reaction of an anhydride with an alcohol to form an ester, gave an inconveniently long reaction time, N-methylimidazole (NMID) and 4-(N,N-dimethylamino)pyridine (DMAP) were found to increase greatly the rate of esterification.     

十一烯酸基乳化剂制备及应用研究

利用十二醇(DA)与十一烯酸(UA)/马来酸酐(MAH)共聚物通过酯化反应制备了UMA-DA聚合物，并将聚合物作为乳化剂用于UA与甲基丙烯酸甲酯(MMA)的乳液聚合中。FT-IR分析表明：DA中的羟基与UMA共聚物中的酸酐发生了反应。¹H NMR结果表明：在δ 3.2~3.4处有明显的—O—CH₂—质子信号，表明成功制备了UMA-DA共聚物。通过表面张力法对UMA皂化物的临界胶束浓度(CMC)值进行了测定，UMA-DA的CMC值为9.6 g/L，此时表面张力γ_CMC为23.04 mN/m, UMA-DA的γ_CMC值要远低于纯水(71.97 mN/m)。在乳液聚合时，随UMA-DA用量的不断增加，乳液粒径和粒径分散系数(PDI)增大，凝胶率逐渐减小。当自制乳化剂UMA-DA用量为总单体的10%且UA与MMA质量比10 : 90时乳液较为稳定，总单体转化率为98.1%。     

New resin systems for high performance top coats

Maleic anhydride copolymer was synthesized and reacted with mono functional alcohols. The reaction was slower than that between monomeric anhydride and alcohol because of the polymer effect. Under heating, recyclization of the half ester to anhydride occurred. This was examined with reference to the structure of alcohols as well as types of catalysts. The maximum recyclization ratio obtained was as high as 84%, while that of copolymers produced with maleic anhydride monoalkyl ester was very low. A trans structure is formed through free rotation at the terminal of the propagating polymer radical in the latter polymer and this is hardly recyclized. A clearcoat obtained by combination of a half ester copolymer and a copolymer containing both hydroxyl and oxirane groups showed excellent acidic water resistance. These findings have been fully developed for the formulation of a 1-package acid rain resistance finish.     

Morphology of nylon 6/acrylonitrile–butadiene–styrene blends compatibilized by a methyl methacrylate/maleic anhydride copolymer

The morphologies of nylon 6/acrylonitrile–butadiene–styrene blends compatibilized with a methyl methacrylate/maleic anhydride copolymer, with 3–20 wt % maleic anhydride, were examined by transmission electron microscopy. Some staining techniques were employed for identifying the various phases. The binary blends were immiscible and exhibited poor mechanical properties that stemmed from the unfavorable interactions among their molecular segments. This produced an unstable and coarse phase morphology and weak interfaces among the phases in the solid state. The presence of the copolymer in the blends clearly led to a more efficient dispersion of the acrylonitrile–butadiene–styrene phase and consequently optimized Izod impact properties. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3512–3518, 2003     

Studies of moisture induced crosslinking in a novel vinyl ether-maleic anhydride copolymer

A novel vinyl ether, 2,2-dimethyl-4-vinyloxymethyl-1,3-dioxolane (DMVMD), that has a dimethyl ketal protected vicinal diol functionality, was synthesized from readily available starting materials, such as glycerol, acetone and acetylene. Copolymerisation of DMVMD with maleic anhydride (MAH) in various molar ratios was carried out using a free radical initiator. The composition of the copolymer was established by conductometric titration, and was found to be 1 : 1 irrespective of the monomer feed composition thus establishing its alternating nature. The copolymer formed clear free standing films upon solvent casting which became insoluble upon prolonged exposure to ambient atmosphere. The insolubility is ascribed to moisture induced crosslinking. A plausible mechanism for the crosslinking involves the hydrolysis of some of the anhydride groups, followed by acid catalysed deketalization, and then by the reaction of the alcoholic groups, thus generated, with the residual anhydride to give ester crosslinks. This hypothesis was confirmed both by model reactions and in situ FT-IR studies. Received: 18 November 1996/Revised: 23 January 1997/Accepted: 7 February 1997     

Polymer supports based on maleic anhydride copolymers: Preparation of beaded copolymers of maleic anhydride on dimethylacrylamide prepolymers

A new technique is described whereby maleic anhydride copolymers are formed within the swellable beads of dimethylacrylamide pre-polymers. Incorporation of a divinyl compound during the copolymerization, or diamine condensation of a pre-formed soluble copolymer, provides a wide range of anhydride containing resins whose conversion to the corresponding acidic or succinimido derivatives, is briefly described.     

溶液聚合法合成苯乙烯-马来酸酐交替共聚物

在过氧化苯甲酰(BPO)引发下,以丁酮为溶剂,采用溶液聚合法合成了苯乙烯-马来酸酐共聚物,并详细研究了温度、引发剂用量、苯乙烯与马来酸酐配比、单体(苯乙烯与马来酸酐)质量分数及聚合时间对聚合反应的影响。研究表明,在温度80℃,x(BPO)=0.6%(相对于苯乙烯与马来酸酐),n(苯乙烯)∶n(马来酸酐)=1∶1,w(单体)=15%(相对于混合溶液),反应时间4 h的条件下,聚合物收率可达99%。采用13CNMR、IR、GPC、元素分析对共聚物结构进行了表征。利用TG测定了其热稳定性。结合共聚物的元素分析与13CNMR的分析结果,表明合成的苯乙烯-马来酸酐共聚物是一种交替共聚物。     

橡胶化学接枝改性的研究进展

综述了以马来酸酐、甲基丙烯酸甲酯等低分子化合物为接枝单体对橡胶进行化学接枝改性的研究及应用情况,分别介绍了反应原理、不同相之间的作用和接枝物结构与表征后,提出用该方法提高短纤维与橡胶间粘结强度的构想.     

Improved performance of a protein array using conjugated polymers as capture phase for HIV serodiagnosis

A modified recombinant protein derived from the viral capsid of the human immunodeficiency virus (HIV) was coupled to a copolymer of maleic anhydride and methyl vinyl ether (MAMVE). The conjugated copolymer was spotted versus free protein in 96‐well microplates. The conjugated copolymer largely improved detection sensitivity of anti‐P24 antibodies in infected human sera. Results obtained with immuno‐linked sorbent array (ILISA) were correlated with those generated with a standard enzyme‐linked immunosorbent assay (ELISA). Serum dilution dynamic range was varied from 1/5000 to 1/150, and inter‐well coefficient of variation was below 8%. Copyright © 2004 Society of Chemical Industry     

Enzyme‐catalyzed copolymerization of oxiranes with dicarboxylic acid anhydrides

Ring‐opening copolymerizations of the oxiranes glycidyl phenyl ether (GPE) and diglycidyl ether of bisphenol A (DGEBA) with a dicarboxylic acid anhydride [methyl hexahydrophthalic anhydride, nadic anhydride, maleic anhydride (MA), or itaconic anhydride (IA)] were carried out with the lipases Candida cylindracea (CCL), Lipozyme TL‐IM (LIM), and Novozyme 435 (N435) as catalysts. The CCL‐catalyzed reaction of DGEBA with MA or IA (at a 1:2 molar ratio) at 80°C resulted in only partial curing. We monitored the reactions by Fourier transform infrared spectroscopy and by following the changes in the intensities of carbonyl stretching frequencies of the anhydride and ester groups. The reactivity of the oxirane group in GPE was higher than that in DGEBA; this may have been due to the higher viscosity of DGEBA. The reactivities of the enzymes for the copolymerization of the oxiranes and dicarboxylic acid anhydride were in the order LIM > CCL > N435. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 697–704, 2005     

Infrared and nuclear magnetic resonance of maleic anhydride copolymers and their half esters

Infrared and NMR group-type methods for the analysis of the anhydride content of maleic anhydride copolymers such as poly(maleic anhydride-co-α-olefin) and the half ester content of their reaction products with alcohols are described. The infrared analyses are based on the integrated absorptivities of the anhydride carbonyl and the combination of the acid and ester carbonyl. The NMR method is based on the intensities of the various chemically shifted groups in the copolymer. The use of dimethyl sulfoxide as an auxiliary solvent has made the infrared analysis possible.     

Reaction of Maleic Anhydride with cis-Isolated Unsaturated Fatty Acid Esters

The structures of maleic anhydride adducts of essentially pure oleic, linoleic and linolenic methyl esters have been determined. The cleavage of the methyl oleate adduct yields a product with a succinyl structure, with or without shift of the double bond; four isomeric structures are possible. The first adduct of maleic anhydride with methyl linoleate is a succinyl derivative followed by a shift into the conjugated isomer with which the second maleic anhydride reacts via a 1–4 Diels Alder addition to yield a second adduct having a cyclohexene structure. The first two moles of maleic anhydride add to methyl linolenate to form di-succinyl derivatives followed by a shift into conjugated diene and triene. The third maleic anhydride adds via a 1–4 addition to yield a disuccinyl and one 1–4 adduct. A number of isomers are possible for the linoleate and linolenate adduct.     

Assignment of 13C NMR chemical shift and microstructure of copolymers of 2-chloroethyl vinyl ether-maleic anhydride and n-butyl vinyl ether-maleic anhydride

Summary The chemical shift in the ¹³C NMR spectra of copolymers of 2-chloroethyl vinyl ether (CEVE) and maleic anhydride (MA), and of n-butyl vinyl ether (BVE) and MA is assigned. It is found that both copolymers are made of completely alternating monomer unit sequences and that the proportion of cis linkage configuration at the cyclic MA units is 45 % and 47 % in the CEVE-MA copolymer and in the BVE-MA copolymer, respectively. Depending on the relative orientation of the cyclic anhydride group, quasi “isotactic” and quasi “syndiotactic” tacticity are considered, with quasi “syndiotactic” diads shielding the vinyl ether carbons more effectively. Received: 19 April 1999/Accepted: 17 June 1999     

DMC催化马来酸酐与环氧丙烷开环共聚行为类型及动力学的研究

研究了双金属氰化络合物（DMC）催化剂催化马来酸酐（MAn）与环氧丙烷（PO）开环共聚行为类型及动力学特征.用IR和1H-NMR表征了共聚物结构,结果表明MAn单体在DMC催化剂催化下不能开环均聚合,聚合为交替共聚.开环共聚合行为类型研究表明,以DMC催化剂催化MAn-PO开环共聚合中,PO单体竞聚率r1〉0、MAn单体竞聚率r2=0,进一步证明此聚合为交替共聚.以共聚行为类型为依据,对聚合动力学进行了研究,结果表明：共聚合反应动力学方程式为Rp=K[C][M],聚合反应速率与单体浓度及催化剂浓度均成一次方关系.     

梳型聚羧酸高效减水剂的合成和应用性能述评

介绍了梳型聚羧酸高效减水剂合成研究及对水泥应用上的高分散性能。梳型聚羧酸高效减水剂分为甲基丙烯酸类共聚物和马来酸酐类共聚物,介绍了合成梳型聚羧酸高效减水剂的主要组分大分子单体的制备、聚合和合成结构的控制方法。综合国内外的研究成果简要介绍了聚羧酸混凝土高效减水剂分子结构和性能的关系、测试和表征方法、对水泥颗粒的分散机理等。