Surface Modification of Nanoclays with Styrene-Maleic Anhydride Copolymers

This study presents the modification of surfaces of nanoclays, halloysite nanotubes (HNT) and sepiolite (SEP), with styrene-maleic anhydride copolymers (SMA) via esterification reaction between hydroxyl groups of the nanoclays and anhydride groups of SMA. The structural, thermal, and morphological analyses of the modified nanoclays were performed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), thermal gravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM). All of these results suggested that the expected modification of HNT and SEP surfaces were performed. Although XRD patterns of HNT containing samples showed that the basal spacing shifted to higher distances, it was found that those of the crystalline structure of SEP remained unchanged. Thermal gravimetric analysis exhibited that SMA copolymers were grafted onto the surfaces of nanoclays varying amounts between 15 and 43 wt. % depending on the types of nanoclays and SMA copolymers. This modification indicates that these nanoclays can be added to the polystyrene matrix without any compatibilizers.

Influences of Reactive Compatibilizer R-Styrene-Maleic Anhydride Copolymer on PA6/PP Blends

The effect of R-styrene-maleic anhydride copolymer(R-SMA) compatibilzation on Nylon 6(PA6)/polypropylene(PP) blends has been investigated experimentally through Molau test,microscopic morphology,and chemical structure.Results show that the moderate R-SMA addition can promote reaction between anhydride in R-SMA and amino in PA6,and lead to a new PA6-g-R-SMA copolymer in the blends.Such PA6-g-R-SMA copolymer in the blends can effectively reduce the interfacial tension and PP particle size,and improve the compatibility of two immiscible phases in the blends.The crystallinity of PA6 in PA6/PP blends has greatly decreased by PP blends.The blends have the best comprehensive mechanical and thermal properties when the mass ratio of PA6/PP/R-SMA is 90:10:2 to 90:10:4.The impact strength of the PA6/PP blends with the compatibilizer is increased by more than 150%.

CONTROLLED RADICAL COPOLYMERIZATION OF STYRENE AND MALEIC ANHYDRIDE UNDER GAMMA RADIATION IN THE PRESENCE OF BENZYL DITHIOBENZOATE

The copolymerization of styrene (St) with maleic anhydride (MAh) under gamma radiation at room temperature in the presence of benzyl dithiobenzoate (BDTB) was found to display 'living' nature evidenced by constant concentration of chain radicals during the copolymerization, linear evolution of molecular weights with conversion and narrow molecular weight distribution (M-w/M-n = 1.23-1.35). The compositional analysis and the sequence structural information of the copolymers obtained from DEPT (Distortionless Enhancement by Polarization Transfer) experiments demonstrate that the copolymers obtained also possess strictly alternating structure.

Kinetic Study of Carbonylation of Methyl Acetate to Acetic Anhydride Catalyzed by Rhodium Complex with a Ligand of Copolymer of Vinyl-acetic Ester and Acrylonitrile

The copolymer of vinyl acetic ester and acrylonitrile is used to react with [Rh（CO）2Cl]2to form a complex which can be used in the carbonylation of methyl acetate to acetic anhydride. Many factors affecting the reaction rate, catalytic activity and selectivity have been investigated. The reaction rate depends on rhodium complex and methyl iodide, and is differant from that of homogenous small molecular rhodium complex catalyst. It is revealed thatthe reaction rate is zero order in CO, first order in Rh and LiOAc, but the order in CH3I is complicated. The causes of these phenomena are discussed based on the mechanism of carbonylation of methyl acetate.

A NOVEL COPOLYMER-BOUND CIS-DICARBONYLRHODIUM COMPLEX FOR THE CARBONYLATION OF METHANOL TO ACETIC ACID AND ACETIC ANHYDRIDE

A series of porous microspheres of linear and ethylene diacrylate (M') cross-linked copolymers of 2-vinylpyridine (V) and methyl acrylate (M) reacted with tetracarbonyldichlorodirhodium to form a series of cis-dicarbonylrhodium chelate complex (MVRh and MVM 'Rh). They are thermally stable yet very reactive in the carbonylation of methanol to acetic acid, and of methanol-acetic acid mixture to acetic acid and acetic anhydride with a selectivity of 100% under relatively mild and anhydrous conditions.

POLYMERIC IONIC CONDUCTORS MODIFIED WITH POLAR GROUPS: PART Ⅱ. STRUCTURE-IONIC CONDUCTION RELATION IN LI-COMPLEX BASED ON MALEIC ANHYDRID E-COPOLYMERIZED METHACRYLATES

Ringlike polar monomer maleic, anhydride (MAn) was copolymerized with oligo (oxyethylene) methacrylate (MEO_n), and its effect on ion conduction property of the corresponding polymer-salt complexes was studied. As a consequence the introduction of MAn onto polymer chain retards crystallization of the ether pendants considerably, and improves the ion conductivity to a larger degree compared with other polar groups once investigated (σ_(max),25℃=8.5×10^(-5) S/cm). The structure-ion conduction relation in the polymer-salt matrix is also analyzed macroscopically through the correspondence between composition-dependences of polymerization conversion and isothermal ion conductivity, and microscopically through the measurements of cross polarized light and electron transmission.

SYNTHESIS AND THERMAL PROPERTIES OF A NEW CHOLIC ACIDCONTAINING COPOLYMER

A new copolymer was synthesized by free radical polymerization in solution from methyl 3α-methylacryloyl-7α, 12α-dihydroxy-5β-cholan-24-oate (MACAME) and maleic anhydride (MAN). The copolymer was characterized by FT-IR and functional group analysis. The reactivity ratios of the two monomers were estimated [r_1 = 11.6 (MACAME), r_2 = 0.01(MAN)] by conducting a series of copolymerizations with a variety of monomer feed compositions and analyzing thecopolymer composition. Thermogravimetric and differential scanning calorimetric analyses of the samples indicate that thecopolymer possesses good thermal stability. The temperature at which the copolymer samples experienced a 10% weight loss(T_(WL)) is over 287℃, and the T_g ranged from 174 to 185℃ for the copolymers.

Potassium Acetate/18-Crown-6 Pair:Robust and Versatile Catalyst for Synthesis of Polyols from Ring-Opening Copolymerization of Epoxides and Cyclic Anhydrides

Efficient synthesis of polyester polyols with tunable molecular weight and microstructures from cyclic anhydride/epoxide mixtures by taking advantage of chain transfer reaction remains a great challenge,because most of the catalysts exhibit poor tolerance to chain transfer agent(CTA).In this contribution,we demonstrated that potassium acetate(KOAc)and 18-crown-6(18-C-6)combination has great potential in the synthesis of diverse polyester polyols with controllable molecular weight and high-end group fidelity.Com-pared with KOAc,KOAc/18-C-6 pair could induce a much faster chain transfer between the active and dormant chains,and thus produce polyester polyols with narrow and monomodal distribution.In addition,polyester polyols could be efficiently prepared in laboratory by using commercially available cyclic anhydride without further purification(containing about 2%diacid residual as CTA)with an extremely low catalyst loading([catalyst pair]:[anhydride]:[epoxide]=1:50000:250000,[catalyst pair]=0.0004 mol%).KOAc/18-C-6 could also promote the self-switchable copolymerization of cyclic anhydride/epoxide/cyclic ester mixtures.Ring-opening copolymerization of cyclic ester was initiated automatically after the full conversion of cyclic anhydride,finally producing polyester polyols with ABA-type block structure.

接枝共聚物对乙烯-乙烯醇共聚物/聚乙烯共混物结构及性能的影响

通过熔融共混法制备了乙烯-乙烯醇共聚物(EVOH)/低密度聚乙烯(LDPE)共混物,再加入马来酸酐接枝聚乙烯(PE-g-MAH)用于促进EVOH的分散性。利用DSC、SEM、力学性能测试、阻隔性能测试等方法表征了共混物的结构及PE-g-MAH的加入对共混物性能的影响。实验结果表明,LDPE与EVOH不相容,EVOH以球形颗粒均匀分散在LDPE基体中,添加PE-g-MAH后可显著改善EVOH的分散性,大幅降低EVOH的结晶温度,进一步提高EVOH/LDPE共混物的强度及对一类萜类物质的阻隔性能。另外,当EVOH含量为10%(w)时,EVOH/LDPE共混物的阻隔性能相对纯LDPE有明显提升,之后进一步提高EVOH含量,阻隔性能变化不大。

PE/SEBS-g-MAH/SEBS的制备及防污性能

以聚乙烯(PE)网衣为基材,苯乙烯-乙烯/丁烯-苯乙烯嵌段共聚物接枝马来酸酐(SEBS-g-MAH)和苯乙烯-乙烯/丁烯-苯乙烯嵌段聚合物(SEBS)为原料,通过浸涂法制备得到PE/SEBS-g-MAH/SEBS(PSMS);分析讨论了不同SEBS附着率时PSMS的力学性能、表面形貌、表面性质、抗蛋白吸附和抗大肠杆菌吸附等性能。结果表明,PSMS表面呈大小不一的泡孔形貌,且随着SEBS附着率的增大,PSMS表面泡孔密度增大,拉伸强度先增加后降低。当SEBS附着率为46.1%时,PSMS的拉伸强度和表面自由能分别为6.045 MPa和14.055 mN/m,抗蛋白吸附率达93.21%,同时兼具良好的抗大肠杆菌吸附性能。除此之外,PSMS在海洋挂板实验中也表现出良好的防污性能。

PRELIMINARY STUDY OF EXTRACTABLE PROTEIN BINDING USING MALEIC ANHYDRIDE COPOLYMER

A preliminary study of using maleic anhydride copolymer for protein binding has been carried out. The polymeric films were prepared by compression of the purified resin and annealing the film to induce efficient back formation of the anhydride groups. The properties of the film surface were analyzed by attenuated total reflection Fourier transforms infrared spectroscopy and water contact angle measurements. The protein content was determined by Bradford assay. To obtain optimum conditions, immersion time for protein binding was examined. Results revealed that proteins can be successfully immobilized onto the film surface via covalent linkage. The efficiency of the covalent binding of the extractable protein to maleic anhydride-polyethylene film was estimated at 69.87 ug/cm2, although the film had low anhydride content （3%） on the surface.

Homopolymerization and Copolymerization of Adipic Anhydride with ε-Caprolactone Catalyzed by Rare Earth Trisphenolate

己二酸酐的戒指洞聚合和己二酸酐与的戒指洞 copolymerization ? 单个部件稀土元素 trisphenolate 催化的 -caprolactone 被报导了。(CL-b-AA ) 共聚物的结构被秒， 1H NMR 和 DSC poly 描绘了。

Exploiting styrene-maleic acid copolymer grafting chromatographic stationary phase materials for separation of membrane lipids

High performance liquid chromatography-mass spectrometry is one of the most commonly used strategies for lipid analysis.The development of versatile chromatographic stationary phases to meet the increasing demands for separation of complex lipids is very important.Styrene-maleic acid(SMA)copolymer is an amphiphilic polymer,which has been proven to have the ability to solubilize lipid molecules of various structures.In this study,styrene-maleic anhydride copolymer coated silica was first prepared by the thiol-ene click reaction.With L-cysteine hydrochloride or dodecanol as the post-modification reagents,Sil-SMA-amino acid and Sil-SMA-dodecanol stationary phase materials were further successfully fabricated via nucleophilic ring-opening reaction.The Fourier-transform infrared,thermogravimetric analysis,and elemental analysis results confirmed the two stationary phase materials were successfully prepared.Furthermore,both the Sil-SMA-dodecanol column and the Sil-SMA-amino acid column possessed reversed-phase/hydrophilic interaction/ion exchange mixed-mode retention mechanisms.The column efficiency of the Sil-SMA-derivatives columns reached 77,300 N/m.Based on the mixed-mode retention characteristics,the Sil-SMA-derivatives columns achieved both the lipid classes and species separation via a single column.The Sil-SMA-amino acid column was further successfully used to separate lipid extract from gastric cancer cell membrane.All these results demonstrated that the SMA-based stationary phase materials have a good potential for use in lipid separation.

马来酸酐共聚物微球对聚丙烯光扩散性能的影响

利用自稳定沉淀聚合技术制备的马来酸酐共聚物微球作为光扩散剂,通过熔融共混的方法制备了光扩散聚丙烯。筛选了聚丙烯基体,研究了共聚物微球对聚丙烯流变性能、光扩散性能和力学性能的影响。研究结果表明,马来酸酐共聚物微球作为光扩散剂可以提高聚丙烯的光扩散性能,共聚物微球添加量为2%时可制备得到雾度大于95%且透光率大于70%的光扩散聚丙烯产品,同时其拉伸强度和弯曲模量达到34 MPa和1.6 GPa,可应用于照明领域。

PE-g-MAH粘接剂的制备及其在阻隔膜中的粘接性能研究

采用双螺杆熔融挤出法制备了马来酸酐接枝聚乙烯(PE-g-MAH)。探讨了在以基体树脂为线型低密度聚乙烯(LLDPE)的基础上,添加不同种类引发剂含量、不同接枝单体马来酸酐(MAH)含量对制备出PE-g-MAH的性能的影响。同时也探究了不同接枝率、熔融指数以及晶点个数的PE-g-MAH粘接剂在乙烯-乙烯醇共聚物(EVOH)阻隔膜上粘接性能的影响。通过傅里叶变换红外光谱对接枝产物进行定性表征并分析接枝物接枝率,通过熔体流动速率测试分析其流动性,通过180°剥离强度测试分析粘接剂的性能。研究结果表明:当引发剂为过氧化二异丙苯(DCP)且添加0.05份,MAH添加1份时,PE-g-MAH接枝率为0.68%,熔融指数为0.94 g·(10 min)^(-1),晶点个数为12,此时材料粘接性能最佳;选择EVOH作为阻隔层粘接,当接枝率为0.68%时,PE-g-MAH的剥离强度达到最大值为69.0 N/cm,PE-g-MAH粘接剂的粘接性能达到相对最佳。

具有ZnS负载富羧基PVDF复合膜的制备及乳液分离和光催化染料降解

含大量有机染料的含油废水对环境的污染日益严重。超润湿材料具有特殊的润湿性,在膜分离技术中得到了广泛的应用,其优异的乳液分离性能与特定的表面形貌有关。本研究先通过溶液转化法制备了聚偏氟乙烯/乙烯-co-马来酸酐共聚物(PVDF/PEMA)膜,后依次进行酸碱处理制备出富羧基离子的PVDF复合膜,最后在膜表面原位沉积ZnS微纳米颗粒。制备的复合膜在水中表现出超疏油性,对含植物油的水包油乳液的分离效率达到97%以上。此外,该膜具有自洁性和抗污染性。对亚甲基蓝降解效率高达98%以上,重复5次吸附-降解实验表面该膜具有优异的可重复使用性。因此,该膜在乳液分离和染料降解方面具有潜在的应用前景。

异丁烯-马来酸酐共聚物凝胶注模成型制备多孔氮化硅陶瓷

以不同粒径的氮化硅粉为原料,采用异丁烯-马来酸酐共聚物凝胶注模成型制备多孔氮化硅陶瓷,研究不同粒径氮化硅颗粒在异丁烯-马来酸酐共聚物水溶液中的分散性及氮化硅颗粒浆料的流变性能,对烧结样品的物相、微观形貌和结构以及介电性能进行表征与分析。结果表明:粒径小于0.5μm的氮化硅颗粒在异丁烯-马来酸酐共聚物水溶液中更易团聚而沉降,氮化硅颗粒浆料的黏度、切应力比粒径为1~3μm的氮化硅颗粒浆料的大;不同粒径原料制备的氮化硅陶瓷的主晶相为α-氮化硅和β-氮化硅,样品的烧结收缩率、密度差异较小,孔隙率约为20%,抗弯强度均大于400 MPa。

单分散马来酸酐/己烯交联共聚物微球的制备

采用沉淀聚合法制备了马来酸酐/己烯交联共聚物微球,利用FTIR,TG,SEM等方法研究了微球的化学组成、形貌、粒径和性能,以及聚合条件对微球形貌、粒径及粒径分布的影响。实验结果表明,聚合产率随反应时间的延长、原料浓度和交联剂用量的增加而增加,随聚合温度的升高呈先增加后减少的趋势;共聚物微球形貌受温度影响较小,主要取决于反应时间、原料浓度及交联剂用量等因素;通过调控反应条件可以得到粒径约1μm、粒径分散指数小于1.01的单分散马来酸酐/己烯交联共聚物微球。

SMA两性衍生物复鞣剂的制备与复鞣性能研究

在DMF溶剂体系中,以N,N-二甲基乙醇胺(DEMA)对苯乙烯-马来酸酐共聚物(SMA)进行酯化改性,制备了一系列两性SMA衍生物(SMA-DEMA)。将系列产物的钠盐应用于铬鞣坯革复鞣工序中,并与SMA钠盐进行对比。结果表明,用两性SMA衍生物钠盐复鞣的坯革纤维表面正电性提高,对阴离子染料吸收结合性增强,坯革败色作用明显减弱;坯革的抗张强度、抗撕裂强度、热稳定性和粒面观感等复鞣效应与SMA钠盐复鞣基本接近。

改性苯乙烯-马来酸酐共聚物色谱固定相用于磷脂分离分析

磷脂是重要的信号分子,磷脂的代谢与多种疾病密切相关。因此,开展磷脂的分离分析研究至关重要。苯乙烯-马来酸酐共聚物(SMA)作为一种新型两亲性交替共聚物可以插入生物膜的磷脂双分子层中,形成以膜蛋白质为中心的脂质纳米盘,对膜蛋白质和磷脂具有良好的增溶作用。本文基于“点击”反应和自由基聚合反应,将对磷脂具有良好增溶性能的SMA接枝到硅胶表面,然后以蛋氨酸甲酯盐酸盐(MME·HCl)为开环试剂,通过亲核开环反应对SMA进行修饰,制备了新型的改性SMA修饰色谱固定相(Sil-SMA-MME)。结合高效液相色谱-紫外检测法,利用酰胺类和核苷/核酸碱基类以及苯酚类3类小分子物质对填充Sil-SMA-MME色谱柱的保留机制和分离性能进行了系统评价,Sil-SMA-MME色谱柱具有典型的亲水作用保留机制,其柱效最高可达90900 N/m,并显示了良好的分离选择性。进一步结合高效液相色谱-蒸发光散射检测法,考察了Sil-SMA-MME色谱柱对磷脂样品的分离性能。二棕榈酰磷脂酰丝氨酸钠(DPPS)、二油酰磷脂酰胆碱(DOPC)、二棕榈酰磷脂酰乙醇胺(DPPE)和4种磷脂酰胆碱(PC)类标准品溶血卵磷脂(LysoPC)、二肉豆蔻酰磷脂酰胆碱(DMPC)、二硬脂酰磷脂酰胆碱(DSPC)、二棕榈酰磷脂酰胆碱(DPPC)均可实现基线分离,并且成功地实现了南极磷虾油和人血清磷脂提取物的分离分析。以上结果表明,所制备的Sil-SMA-MME色谱柱在磷脂类物质分离分析中具有良好的应用潜力。