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在室温条件下,以甲醇和水为混合溶剂,由四溴代对苯二甲酸(H2TBTA)和硝酸铜分别与吡啶(py)和咪唑(im)构筑了2个一维(1D)铜配位聚合物:[Cu(TBTA)(py)3]n(1)和{[Cu(TBTA)(im)3]·(H2O)}n(2),对2个配合物进行了元素分析、红外分析、热重分析和X-射线单晶衍射等表征。在配合物1和2中,中心Cu(Ⅱ)离子都处于五配位环境;H2TBTA配体中羧基均采用单齿配位模式;配合物2存在π-π相互作用且氢键较1丰富。 相似文献
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采用十二烷基硫酸钠(SDS)为乳化剂、十六醇(CA)为难溶助剂,引发醋酸乙烯酯(VAc)进行细乳液聚合,以偶氮二异庚腈(ADMVN)为引发剂时,制得了平均聚合度达1.5×104~2.0×104聚醋酸乙烯酯(PVAc)和4.1×103~6.6×103的聚乙烯醇(PVA);以偶氮二脒基丙烷盐酸盐(AAPH)为引发剂时,制得了平均聚合度达1.5×104~2.0×104的PVAc和2.1×103~4.4×103的PVA.研究了引发剂浓度、温度、油水比对产物聚合度、转化率的影响,讨论了SDS∶CA摩尔比对PVAc微球粒径分布及其成粒机理的影响.当cCA∶cSDS=3∶1时得到的细乳液体系稳定性最好,以ADMVN和AAPH引发聚合时均为液滴成核为主,其中以ADMVN引发得到PVAc微球的粒度分布窄于AAPH. 相似文献
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Two 2D layer complexes {[La(TBTA)1.5(phen)2H2O]·3H2O}n (1) and {[Ce(TBTA)1.5(phen)2H2O]·3H2O}n (2) (H2TBTA = 2,3,5,6-tetrabromoterephthalic acid, phen = 1.10-phenanthroline) have been synthesized and characterized by single-crystal X-ray diffraction, elemental analyses, IR spectra and thermogravimetric analyses. Both crystals belong to monoclinic, space group P21/n. Crystal data for 1: a = 8.7097(11), b = 34.276(4), c = 13.7281(17) , β = 95.397(2)o, V = 4080.1(9) 3, Z = 4, LaC36H24Br6N4O10, Mr = 1290.96, Dc = 2.102 g/cm3, μ(MoKα) = 6.983 mm-1, F(000) = 2460.0, T = 296(2) K, the final R (I > 2σ(I)) = 0.0478 and wR (all data) = 0.0985 for 10127 independent (Rint = 0.0775) and 7137 observed reflections with I > 2σ(I). Crystal data for 2: a = 8.709(2), b = 34.202(9), c = 13.685(4), β = 95.714(4), V = 4055.9(19)3, Z = 4, CeBr6C36H24O10N4, Mr = 1292.17, Dc = 2.116 g/cm3, μ(MoKα) = 7.094 mm-1, F(000) = 2464.0, T = 296(2) K, the final R (I > 2σ(I)) = 0.0590 and wR (all data) = 0.1453 for 10014 independent (Rint = 0.1253) and 6081 observed reflections with I > 2σ(I). Both complexes are allomerism with the general molecular formula of {[M(TBTA)1.5(phen)2H2O]·3H2O}n. In the structures, the H2TBTA ligands adopt a monodentate coordination mode. Both the 2D layer frameworks are further extended to be 3D layers via H-bonding interactions. 相似文献
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低温悬浮聚合法合成超高聚合度的聚乙烯醇 总被引:1,自引:0,他引:1
以偶氮二异庚腈(ADMVN)为引发剂,通过悬浮聚合法合成聚醋酸乙烯(PVAc),PVAc经醇解制备超高聚合度(Pn)的聚乙烯醇(PVA)。实验结果显示较适宜的反应条件为:VAc 80 g,V(H2O)∶V(VAc)=1∶1,cADMVN=0.1%(以VAc质量计),悬浮剂浓度(cPVA-2288)=1.5%(以水质量计),搅拌速度(r)300 rmp,于30℃反应24 h,单体VAc的转化率超过90%,PnPVA为4.0×103~6.6×103。cPVA-2288和r是影响PVAc颗粒直径(DPVAc)及其分布的主要因素:DPVAc∝[cPVA-2288]-1.45,DPVAc∝r-1.79。 相似文献
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