This paper reports a new approach to estimate kinetic parameters for the thermal decomposition of the solid state from TG-DTG or DSC curve.Reduced equations are derived for the first tlme.The validity of these equatio...This paper reports a new approach to estimate kinetic parameters for the thermal decomposition of the solid state from TG-DTG or DSC curve.Reduced equations are derived for the first tlme.The validity of these equations was demonstrated employing data obtained from the dehydration process of calcium oxalate monohydrate.展开更多
The kaolinite-polyacrylamide inte rcalation compound was prepared fir st by the displacement reaction of th e kaolinite-formamide intercalatio n precursor with 30%acrylamide ethanol solution,and then the polymeriz ati...The kaolinite-polyacrylamide inte rcalation compound was prepared fir st by the displacement reaction of th e kaolinite-formamide intercalatio n precursor with 30%acrylamide ethanol solution,and then the polymeriz ation under 140℃for 15h with the catalysis of dibenzoyl peroxide.The XRD analy ses showed that the basal spacings of kaolinite-acrylamide intercalation compound and kaolinite-polyacry lamide compound were 1.135nm and 1.144nm respectively.The kaolinite-polya crylamide compound was able to resis t to 30-min washing with water,but th e kaolinite-acrylamide compound was unstable during washing.FT-IR proved that the hydrogen bonds were forme d between kaolinite Si-O group and polyacrylamide NH group and between kaolinite inner surface hydroxyl and polyacrylamide C =O group,and that p arts of NH group keyed into the kaolin ite ditrigonal hole.TG and DTG analysis proved that kaolinite-polyacrylamide was stable under 350℃.A net weight loss of 16.63%between 370℃~500℃is due to the removal of interca lated polyacrylamide from the interlamellar space of kaolinite.These results clearly indicate that acrylamide has been intercalated into the layers of kaolinite and was polymerized in-situ.Based on the TG data,the formula of the kaolinite-polyacrylami de intercalation compound,Al 2 Si 2 O 5 (OH) 4 CH 2 CHCONH 2 0.736 ,can be calculated.展开更多
文摘This paper reports a new approach to estimate kinetic parameters for the thermal decomposition of the solid state from TG-DTG or DSC curve.Reduced equations are derived for the first tlme.The validity of these equations was demonstrated employing data obtained from the dehydration process of calcium oxalate monohydrate.
文摘The kaolinite-polyacrylamide inte rcalation compound was prepared fir st by the displacement reaction of th e kaolinite-formamide intercalatio n precursor with 30%acrylamide ethanol solution,and then the polymeriz ation under 140℃for 15h with the catalysis of dibenzoyl peroxide.The XRD analy ses showed that the basal spacings of kaolinite-acrylamide intercalation compound and kaolinite-polyacry lamide compound were 1.135nm and 1.144nm respectively.The kaolinite-polya crylamide compound was able to resis t to 30-min washing with water,but th e kaolinite-acrylamide compound was unstable during washing.FT-IR proved that the hydrogen bonds were forme d between kaolinite Si-O group and polyacrylamide NH group and between kaolinite inner surface hydroxyl and polyacrylamide C =O group,and that p arts of NH group keyed into the kaolin ite ditrigonal hole.TG and DTG analysis proved that kaolinite-polyacrylamide was stable under 350℃.A net weight loss of 16.63%between 370℃~500℃is due to the removal of interca lated polyacrylamide from the interlamellar space of kaolinite.These results clearly indicate that acrylamide has been intercalated into the layers of kaolinite and was polymerized in-situ.Based on the TG data,the formula of the kaolinite-polyacrylami de intercalation compound,Al 2 Si 2 O 5 (OH) 4 CH 2 CHCONH 2 0.736 ,can be calculated.