二过碘酸合铜(Ⅲ)钾氧化还原引发丙烯酸甲酯在尼龙1010上接枝共聚合反应的研究

以二过碘酸含铜（Ⅲ）钾（简称Cu（Ⅲ））为氧化剂，尼龙1010自剂，组成氧化还原引发体系，于碱性介质中，在尼龙1010表面引发丙烯聚合反应．测定了各种因素对接枝参数的影响．X-射线衍射及表征，并探讨了引发机理．     

二过碘酸合铜(Ⅲ)钾引发丙烯腈在聚丙烯酰胺上接枝共聚合反应的研究

本文以二过碘酸合铜(Ⅲ)钾为氧化剂,聚丙烯酰胺(PAAM)自身为还原剂组成的氧化还原引发体系,在PAAM上引发丙烯腈接枝共聚合反应,获得了高接枝效率和高接枝百分比的产物,由红外光谱、扫描电镜及X射线衍射分析对接枝反应进行了表征,测定了各种条件对接枝参数的影响,并对引发机理进行了探讨。     

二过碘酸合银(Ⅲ)络离子氧化还原引发丙烯酰胺聚合反应动力学的研究

二过碘酸合银[Ag(Ⅲ)]在氧化还原反应中为双电子转移反应,没有中间自由基产生,不能引发丙烯腈聚合^[1,2].我们发现,Ag(Ⅲ)与不同还原剂组成氧化还原体系,在一定条件下,能引发烯类单体聚合.本文研究了Ag(Ⅲ)为氧化剂、丙烯酰胺(AM)为还原剂引发AM聚合反应的动力学,得到了聚合速率方程和表观活化能,测得了聚合物分子量M,探讨了引发机理.     

薄层光谱电化学方法研究[Ag(lO_6)_2]~(7-)和[Cu(lO_6)_2]~(7-)的阴极还原

在碱性介质中只有少数氧化剂如Ag(Ⅲ)及Cu(Ⅲ)仍有较强的氧化性,因此研究Ag(Ⅲ)、Cu(Ⅲ)络合物阴极还原的电极电势、电子转移数及还原机理,对于深入了解它们作为氧化剂时的氧化还原特性是有帮助的.本文用薄层光谱电化学方法测定了二过碘酸合银(Ⅲ)、络离子在不同pH条件下还原反应的E~0′和电子转移数(n),并由此推断阴极还原反应机理,还用同样方法研究了二过碘酸含铜(Ⅲ)络离子的阴极还原.     

二过碘酸合铜(III)氧化氨基丙酸的动力学

高氧化态的过渡金属通常借助与适当多齿配体螯合能稳定存在．例如二羟基二过碘酸合镍（IV）［1，2］和二过碘酸合铜（皿）[3，4]等在适当pH下都是良好的氧化剂．近期Morius[3]和Murthy[4]等人进行了Cu(III）对一元醇、醛等有机化合物的氧化反应动力学研究，两者所得结果有一定的差别．例如前者得出反应对于过碘酸为一1．0级，而后者为一0．45级．由于这类反应比较复杂，而且钢在许多包含有电子转移的生物化学过程中起着重要的作用问，因此对这类反应体系进一步探讨有一定的意义·及实验部分（1）试剂和仪器a一氨基丙酸和其它试剂都不低…     

尼龙1010／马来酸酐接枝聚丙烯共混体系的反应增容

利用Ｍｏｌａｕ实验、红外光谱、电子扫描显微镜等研究了尼龙１０１０与马来酸酐接技改性聚丙烯（ＰＰ－ｇ－ＭＡＨ）共混体系的结构，结果表明，尼龙１０１０分子链中胺基或亚胺基与Ｐｐ－ｇ－ＭＡＨ上的酸酐发生了化学反应，生成的接枝共聚物起到了共混体系增容剂的作用，改善了体系的亲合性。     

尼龙1010非等温结晶动力学与机理研究

尼龙１０１０非等温结晶动力学与机理研究朱诚身，王经武，李卓美（郑州大学材料工程系郑州４５００５２）（中山大学高分子研究所广州５１０２７５）关键词尼龙１０１０，非等温结晶动力学，结晶机理，动力学结晶能力尼龙１０１０的结晶动力学，无论是等温还是非等温，研...     

高锰酸钾—硫脲体系引发丙烯酸接枝共聚尼龙的研究

研究了以高锰酸钾和硫脲组成的氧化还原引发体系,在水介质中,引发丙烯酸接枝共聚尼龙的共聚反应。考察了丙烯酸浓度、引发剂浓度及温度等因素对接枝共聚反应的影响。红外光谱分析和Ｘ射线衍射图谱证明了接枝反应的存在及对聚合物结晶度的影响。     

新化合物KSm（II）Sm（III）F6

新化合物ＫＳｍ（ＩＩ）Ｓｍ（ＩＩＩ）Ｆ＿６吴国庆，郭春红，贯军（北京师范大学化学系，１００８７５）已知的钐（ＩＩ）的化合物的种类很少，除ＳｍＦ＿２外，其他已知的钐（ＩＩＩ）化合物均极不稳定，在含水蒸气的空气里很快被氧气氧化。用氢气还原ＥｕＦ＿３可以得...     

不同分子量尼龙1010的结晶与熔融

不同分子量尼龙１０１０的结晶与熔融＊朱诚身王经武王友文杨桂萍（郑州大学材料工程系郑州４５００５２）陈玉莫志深（东北师范大学分析测试中心长春１３００２４）（中国科学院长春应用化学研究所长春１３００２２）关键词尼龙１０１０，分子量，结晶，熔融＊１９９４＿...     

Grafting of 4‐Vinyl Pyridine onto Nylon‐6 Initiated by Cu(III)

In this article, the graft copolymerization of 4‐vinyl pyridine (4VP) onto nylon‐6 (PA6) using potassium diperiodacuprate (III) (DPC)–PA6 redox system as initiator is investigated in an alkaline medium. The structure and the properties of graft copolymer are confirmed by Fourier transfer infrared spectroscopy (IR), X‐ray diffraction and thermogravimetric analysis (TGA). The mechanism is proposed to explain the generation of radicals and the initiation. The effects of reaction variables, such as the initiator concentration, ratio of 4VP to PA6, pH, as well as reaction temperature and time are investigated. Graft copolymers with high grafting efficiency (>95%) were obtained, which indicated that the DPC–PA6 redox system was an efficient initiator for this graft copolymerization. The quaternized PA6‐g‐P4VP (QPAVP) is proven to be an excellent adsorbent to heavy metal ions.     

Grafting of 4-Vinyl Pyridine onto Nylon-6 Initiated by Redox System

The graft copolymerization of 4‐vinyl pyridine (4VP) onto nylon‐6 (PA6) was studied by using potassium diperiodatonickelate(IV) (DPN)‐PA6 redox system in alkaline medium. The structures of graft copolymers were confirmed by Fourier transfer infrared spectroscopy (FTIR) and X‐ray diffraction. The properties of graft copolymers were investigated by thermogravimetric analysis (TGA). A mechanism was proposed to explain the generation of radicals and the initiation. The effects of reaction variables, such as the initiator concentration, the ratio of 4VP to PA6, pH as well as reaction temperature and time were investigated. Graft copolymers with high grafting efficiency (>95%) were obtained, which indicated that DPN‐PA6 redox system is an efficient initiator for this graft copolymerization. The quaternized PA6‐g‐P4VP (QPAVP) was proved to be an excellent adsorbent to heavy metal ions.     

Graft Copolymerization of Methyl Methacrylate onto Chitosan Initiated by Potassium Ditelluratocuprate(III)

A novel redox system, potassium ditelluratocuprate(III) (DTC)–chitosan, was employed to initiate the graft copolymerization of methyl methacrylate (MMA) onto chitosan in alkali medium. The effects of reaction variables, such as the initiator concentration, ratio of monomer to chitosan, the pH value, as well as reaction temperature and time were investigated, and the grafting conditions were optimized. Graft copolymers with both high grafting efficiency (>90%) and percentage of grafting were obtained, and the rate of polymerization is higher, which indicated that the DTC–chitosan redox system is an efficient initiator for this graft copolymerization. The structures and the thermal property of chitosan and chitosan–g–PMMA were characterized by infrared spectroscopy (IR), X‐ray diffraction and thermogravimetric analysis (TGA). A mechanism is proposed to explain the generation of radicals and the initiation. The graft copolymer was used as the compatibilizer in blends of terpolyamide and chitosan. The scanning electron microscope (SEM) photographs indicated that the graft copolymer improved the compatibility of the blend.     

Grafting of 4-vinyl pyridine onto poly(vinyl alcohol) initiated by potassium diperiodatocuprate(III)

In this article, the graft copolymerization of 4-vinyl pyridine onto poly(vinyl alcohol) via the potassium diperiodatocuprate(III)-poly(vinyl alcohol) redox system as an initiator was investigated in an alkaline medium. The graft copolymer was characterized with Fourier-transform infrared spectra analysis. A mechanism is proposed to explain the generation of radicals and the initiation. The effects of reaction variables, such as the initiator concentration, the ratio of monomer to poly(vinyl alcohol), pH, and reaction temperature and time, are investigated, and the grafting conditions are optimized. Graft copolymers with high grafting efficiency are obtained, thus indicating that potassium diperiodatocuprate(III)-PVA redox system is an efficient initiator for this graft copolymerization. Published in Russian in Vysokomolekulyarnye Soedineniya, Ser. B, 2006, Vol. 48, No. 7, pp. 1190–1194. This text was submitted by the authors in English.     

Polymerization of vinyl monomers initiated by KO2–charge transfer agent systems. II

Vinyl monomers having electron acceptor groups such as nitroethylene, acrylonitrile, and acrolein were polymerized by KO₂–charge transfer agent initiator systems in dimethylsulfoxide (DMSO) at 25°C. The new initiator systems were found to be stable for almost 1 month under nitrogen atmosphere. The initial rate of polymerization was so fast that both conversion and molecular weight of the polymers obtained were high. Especially their molecular weight distribution was observed to be very narrow by means of gel permeation chromatography (GPC). The anion radicals generated by one electron transfer from potassium superoxide (KO₂) to charge transfer agents such as naphthalene, benzoquinone, azobenzene, etc., were suitable as initiator for the anionic polymerization of electron acceptor monomers. Study on block copolymerization of nitroethylene with acrylonitrile or acrolein was also attempted.     

GRAFT COPOLYMERIZATION OF METHYL ACRYLATE ONTO CHITOSAN INITIATED BY POTASSIUM DIPERIODATONICKELATE (IV)

ABSTRACT

A novel redox system, potassium diperiodatonickelate [Ni (IV)]‐chitosan, was employed to initiate the graft copolymerization of methyl acrylate (MA) onto chitosan in alkali aqueous solution. The effects of reaction variables such as monomer concentration, initiator concentration, reaction time, pH and temperature were determined. By means of a series of copolymerization, the grafting conditions were optimized. The maximum grafting percentage obtained was 404.1% when 0.3 g chitosan was copolymerized with 1.8 mL monomer at 35°C for 5 hours with [Ni (IV)]=9.4×10^?4 M and the total volume was 20 mL. Ni (IV)-chitosan system is found to be an efficient redox initiator for this graft copolymerization. A single electron transfer mechanism is proposed to explain the formation of radicals and the initiation. The grafted copolymers were characterized by IR and X-ray diffraction diagrams. The thermal stability of chitosan and chitosan-g-PMA was studied by thermogravimetric analysis (TGA).     

Note Copolymerization of Styrene with Maleic Anhydride Initiated by L-Ascorbic Acid

It is well known that maleic anhydride (MAH) behaves as an electron acceptor and forms charge-transfer complexes with donor monomers such as styrene (ST) [1,2], divinyl ether [3], and some of other olefms [4–61. The charge-transfer polymerization of ST with MAH has been extensively studied [1,7–11]. On the other hand, L-ascorbic acid (L-Asc) in combination with a suitable oxidants proved to be an efficient redox initiator for various vinyl polymerizations. Misra et al. [12] showed that the reduction of peroxides by ascorbic acid follows a chain mechanism with ascorbate and other free radicals as intermediates. Thus, we can expect that such an electron donor might initiate the copolymerization of MAH with ST.     

三价锰离子引发烯类单体在聚乙烯醇上接枝聚合的研究

<正> 无论是淀粉;纤维素,还是聚乙烯醇(PVA)的接枝反应,Ce(Ⅳ)被认为是一个十分有效的引发剂,已有较详尽的研究。与Ce(Ⅳ)相类似,Mn(Ⅲ)也可以和一些高聚物组成氧化还原引发体系,由此产生自由基,引发烯类单体在高分子主干上进行接枝聚合。Ranby等人,以焦磷酸络合的三价锰离子引发烯类单体在纤维素和淀粉的接枝反应中,获得了高效的接枝产物。有用这种引发体系在淀粉上接枝丙烯腈获得吸水276     

高锰酸钾/硫脲引发魔芋粉-丙烯酰胺接技共聚合及产物增稠性研究

用高锰酸钾／硫脲为引发剂，引发魔芋粉(KGM)与丙烯酰胺(AM)的接枝共聚。研究了引发剂浓度、单体浓度、酸度、反应温度、反应时间、反应介质以及KGM预处理方式等对接枝反应的影响，同时还研究了产物的水溶性及增稠性，并探讨了接枝反应机理。