The polymerization of n-hexyl isocyanate(HNCO) was carried out in the presence of a novel single initiator, rare earth tris(2,6-di-tert-butyl-4-methylphenolate)[Ln(OAr)_3]. The influences of reaction conditions such a...The polymerization of n-hexyl isocyanate(HNCO) was carried out in the presence of a novel single initiator, rare earth tris(2,6-di-tert-butyl-4-methylphenolate)[Ln(OAr)_3]. The influences of reaction conditions such as the monomer concentration, the polymerization temperature and time, and the types of solvents on the polymerization of HNCO were studied. Polymerizations of phenyl, i-propyl, p-tolyl, n-butyl and n-octyl isocyanates with La(OAr)_3 were also examined.展开更多
The ring-opening polymerization of 1,4-dioxan-2-one （PDO） was carried out by lanthanum tris（2,6-di-tert-butyl-4- methylphenolate） （La（OAr）3） as novel single component initiaLor. The influences of polymerizatio...The ring-opening polymerization of 1,4-dioxan-2-one （PDO） was carried out by lanthanum tris（2,6-di-tert-butyl-4- methylphenolate） （La（OAr）3） as novel single component initiaLor. The influences of polymerization reaction temperature and the molar ratio of monomer to initiator on the monomer conversion and molecular weight of poly（1,4-dioxan-2-one） （PPDO） were explored. PPDO with high viscosity average molecular weight of 1.95×10^5 can be prepared at 40℃ when [PDO]/ [La（OAr）3] molar ratio was 800. Mechanism investigation shows that the polymerization proceeds through a ＂coordination- insertion＂ mechanism with selective rupture of acyl-oxygen be,nd of PDO.展开更多
目的:建立药用丁基橡胶塞中添加剂[抗氧剂264(2,6-二叔丁基-4-甲基苯酚,简称BHT)和硫化剂可提取硫]的含量测定方法。方法:以二氯甲烷-无水乙醇为提取溶剂,利用高效液相色谱法对药用丁基橡胶塞的BHT和可提取硫含量进行测定,以含0.1%三氟...目的:建立药用丁基橡胶塞中添加剂[抗氧剂264(2,6-二叔丁基-4-甲基苯酚,简称BHT)和硫化剂可提取硫]的含量测定方法。方法:以二氯甲烷-无水乙醇为提取溶剂,利用高效液相色谱法对药用丁基橡胶塞的BHT和可提取硫含量进行测定,以含0.1%三氟乙酸的乙腈-含0.1%三氟乙酸的水(90∶10)为流动相,流速1.0 m L·min^(-1),检测波长280 nm。结果:抗氧剂BHT的线性检测范围0.41~103.00μg·mL^(-1)(r^2=1.000),可提取硫的线性检测范围0.10~103.50μg·mL^(-1)(r^2=0.999 9),BHT和可提取硫的平均回收率分别为95.2%和86.8%。测定7批药用胶塞中BHT与可提取硫含量范围分别为4~206μg·g^(-1)和1~143μg·g^(-1)。结论:本文建立的检测方法经方法学验证,可用于考察药用丁基橡胶塞中BHT和可提取硫的含量及质量控制。展开更多
A new complex with binuclear nickel(Ⅱ) complex [Ni2(bbimp)(CH3CH2OH)2Cl2]Cl· 4H2O (bbimp=2,6 bis[bis(2 benzimidazolylmethyl)]aminomethyl 4 methylpheno)(o)had been synthesized and characterized by elementary anal...A new complex with binuclear nickel(Ⅱ) complex [Ni2(bbimp)(CH3CH2OH)2Cl2]Cl· 4H2O (bbimp=2,6 bis[bis(2 benzimidazolylmethyl)]aminomethyl 4 methylpheno)(o)had been synthesized and characterized by elementary analysis, IR and UV. The molecular structure of the title complex was determined by X ray single crystal diffraction method. The crystal is monoclinic, space group P21/n with a=20.803(2)? , b=30.708(3)? , c=20.959(2)? , β =105.776(2)° , Z=8, V=12885(2)? 3, Dx=1.132Mg· m- 3, μ =0.755mm- 1, F(000)=4592, R1=0.1267, S=1.376. It was showed that the nickel? cation is the central ion of a distorted octahedral coordination with two N belonging to benzimidazole, a bridging phenolate O, a N of tertiary amine, a Cl anion, and an O of an ethanol molecule. Two nickel? cations in a molecular structure had the same coordinated environment. CCDC: 197601.展开更多
文摘The polymerization of n-hexyl isocyanate(HNCO) was carried out in the presence of a novel single initiator, rare earth tris(2,6-di-tert-butyl-4-methylphenolate)[Ln(OAr)_3]. The influences of reaction conditions such as the monomer concentration, the polymerization temperature and time, and the types of solvents on the polymerization of HNCO were studied. Polymerizations of phenyl, i-propyl, p-tolyl, n-butyl and n-octyl isocyanates with La(OAr)_3 were also examined.
基金This work was financially supported by the financial support of National Natural Science Foundation of China (No. 20434020)
文摘The ring-opening polymerization of 1,4-dioxan-2-one （PDO） was carried out by lanthanum tris（2,6-di-tert-butyl-4- methylphenolate） （La（OAr）3） as novel single component initiaLor. The influences of polymerization reaction temperature and the molar ratio of monomer to initiator on the monomer conversion and molecular weight of poly（1,4-dioxan-2-one） （PPDO） were explored. PPDO with high viscosity average molecular weight of 1.95×10^5 can be prepared at 40℃ when [PDO]/ [La（OAr）3] molar ratio was 800. Mechanism investigation shows that the polymerization proceeds through a ＂coordination- insertion＂ mechanism with selective rupture of acyl-oxygen be,nd of PDO.
文摘目的:建立药用丁基橡胶塞中添加剂[抗氧剂264(2,6-二叔丁基-4-甲基苯酚,简称BHT)和硫化剂可提取硫]的含量测定方法。方法:以二氯甲烷-无水乙醇为提取溶剂,利用高效液相色谱法对药用丁基橡胶塞的BHT和可提取硫含量进行测定,以含0.1%三氟乙酸的乙腈-含0.1%三氟乙酸的水(90∶10)为流动相,流速1.0 m L·min^(-1),检测波长280 nm。结果:抗氧剂BHT的线性检测范围0.41~103.00μg·mL^(-1)(r^2=1.000),可提取硫的线性检测范围0.10~103.50μg·mL^(-1)(r^2=0.999 9),BHT和可提取硫的平均回收率分别为95.2%和86.8%。测定7批药用胶塞中BHT与可提取硫含量范围分别为4~206μg·g^(-1)和1~143μg·g^(-1)。结论:本文建立的检测方法经方法学验证,可用于考察药用丁基橡胶塞中BHT和可提取硫的含量及质量控制。
文摘A new complex with binuclear nickel(Ⅱ) complex [Ni2(bbimp)(CH3CH2OH)2Cl2]Cl· 4H2O (bbimp=2,6 bis[bis(2 benzimidazolylmethyl)]aminomethyl 4 methylpheno)(o)had been synthesized and characterized by elementary analysis, IR and UV. The molecular structure of the title complex was determined by X ray single crystal diffraction method. The crystal is monoclinic, space group P21/n with a=20.803(2)? , b=30.708(3)? , c=20.959(2)? , β =105.776(2)° , Z=8, V=12885(2)? 3, Dx=1.132Mg· m- 3, μ =0.755mm- 1, F(000)=4592, R1=0.1267, S=1.376. It was showed that the nickel? cation is the central ion of a distorted octahedral coordination with two N belonging to benzimidazole, a bridging phenolate O, a N of tertiary amine, a Cl anion, and an O of an ethanol molecule. Two nickel? cations in a molecular structure had the same coordinated environment. CCDC: 197601.
