The molecular weight of acrylonitrile/itaconic acid copolymer can be calculated from the intrinsic viscosities of the dilute reaction solutions directly, when the conversion was higher than 90% during the solution pol...The molecular weight of acrylonitrile/itaconic acid copolymer can be calculated from the intrinsic viscosities of the dilute reaction solutions directly, when the conversion was higher than 90% during the solution polymerization. Because of the sample treatment processes such as film preparing, washing, drying and redissolving were simplified, the analysis time was reduced substantially. The proposed method is more suitable for rapid analysis. The measurement error compared with common method of determination for the copolymer in DMSO by single point method was about 1%.展开更多
采用差示扫描量热法,研究了丙烯腈(AN)/丙烯酸(AA)共聚物在空气中的低温热解反应,利用K iss inger方法,计算了AN/AA共聚物热解反应的表观活化能,讨论了不同聚合工艺对共聚物热解反应表观活化能的影响。结果表明,随混合溶剂中二甲基亚砜...采用差示扫描量热法,研究了丙烯腈(AN)/丙烯酸(AA)共聚物在空气中的低温热解反应,利用K iss inger方法,计算了AN/AA共聚物热解反应的表观活化能,讨论了不同聚合工艺对共聚物热解反应表观活化能的影响。结果表明,随混合溶剂中二甲基亚砜含量的增加,共聚物热解反应表观活化能增加;随共聚单体AA含量的增加,共聚物热解反应表观活化能降低;当AA与AN质量配比高于5/95后,共聚物热解反应表观活化能变化不大;随反应温度增加,共聚物热解反应表观活化能增加。展开更多
The pyrolysis reaction of acrylonitrile(AN)/N-vinylpyrrolidone(N-VP) copolymer in air was studied with DSC. The apparent activation energy of pyrolysis reaction of copolymer was calculated by the Kissinger method. The...The pyrolysis reaction of acrylonitrile(AN)/N-vinylpyrrolidone(N-VP) copolymer in air was studied with DSC. The apparent activation energy of pyrolysis reaction of copolymer was calculated by the Kissinger method. The effect of different copolymerization conditions on the apparent activation energy of copolymer was discussed. It was found that with an increase of DMSO concentration in mixture solvent,the degradation apparent activation energy rose rapidly. When the weight ratio of N-VP/AN was less than 5/95, the apparent activation energy of degradation reduced quickly with the comononer N-VP concentration rising, and when the ratio was more than 5/95, the apparent activation energy became almost constant. When the copolymerization temperature rose, the apparent activation energy also increased.展开更多
Effect of inorganic salts on viscosities of dimethyl sulphoxide(DMSO)solutions of acrylonitrile(AN)/ N vinylpyrrolidone( N VP) copolymer was discussed Viscosity was determined by revolving viscosimeter It was shown th...Effect of inorganic salts on viscosities of dimethyl sulphoxide(DMSO)solutions of acrylonitrile(AN)/ N vinylpyrrolidone( N VP) copolymer was discussed Viscosity was determined by revolving viscosimeter It was shown that solution viscosity decreased quickly with addition of KCl and NaCl and the effect of NaCl was more prominent than KCl As the concentration of KCl and NaCl beyond 0 025 mol·L -1 , the viscosity tended to increase The viscosity increased considerably with addition of FeCl 3 and CuCl 2 The change of solution viscosity became less obvious with addition of ZnCl 2 With increasing temperature, the viscosity of copolymer solution containing NaCl decreased most quickly and the copolymer solution containing FeCl 3 decreased most展开更多
文摘The molecular weight of acrylonitrile/itaconic acid copolymer can be calculated from the intrinsic viscosities of the dilute reaction solutions directly, when the conversion was higher than 90% during the solution polymerization. Because of the sample treatment processes such as film preparing, washing, drying and redissolving were simplified, the analysis time was reduced substantially. The proposed method is more suitable for rapid analysis. The measurement error compared with common method of determination for the copolymer in DMSO by single point method was about 1%.
文摘采用差示扫描量热法,研究了丙烯腈(AN)/丙烯酸(AA)共聚物在空气中的低温热解反应,利用K iss inger方法,计算了AN/AA共聚物热解反应的表观活化能,讨论了不同聚合工艺对共聚物热解反应表观活化能的影响。结果表明,随混合溶剂中二甲基亚砜含量的增加,共聚物热解反应表观活化能增加;随共聚单体AA含量的增加,共聚物热解反应表观活化能降低;当AA与AN质量配比高于5/95后,共聚物热解反应表观活化能变化不大;随反应温度增加,共聚物热解反应表观活化能增加。
文摘The pyrolysis reaction of acrylonitrile(AN)/N-vinylpyrrolidone(N-VP) copolymer in air was studied with DSC. The apparent activation energy of pyrolysis reaction of copolymer was calculated by the Kissinger method. The effect of different copolymerization conditions on the apparent activation energy of copolymer was discussed. It was found that with an increase of DMSO concentration in mixture solvent,the degradation apparent activation energy rose rapidly. When the weight ratio of N-VP/AN was less than 5/95, the apparent activation energy of degradation reduced quickly with the comononer N-VP concentration rising, and when the ratio was more than 5/95, the apparent activation energy became almost constant. When the copolymerization temperature rose, the apparent activation energy also increased.
文摘Effect of inorganic salts on viscosities of dimethyl sulphoxide(DMSO)solutions of acrylonitrile(AN)/ N vinylpyrrolidone( N VP) copolymer was discussed Viscosity was determined by revolving viscosimeter It was shown that solution viscosity decreased quickly with addition of KCl and NaCl and the effect of NaCl was more prominent than KCl As the concentration of KCl and NaCl beyond 0 025 mol·L -1 , the viscosity tended to increase The viscosity increased considerably with addition of FeCl 3 and CuCl 2 The change of solution viscosity became less obvious with addition of ZnCl 2 With increasing temperature, the viscosity of copolymer solution containing NaCl decreased most quickly and the copolymer solution containing FeCl 3 decreased most
