The cure kinetics of diglycidyl ether of bisphenol A (DGEBA) with hyperbranched poly (3-hydroxyphenyl) phosphate(HHPP) as the curing agent was investigated by means of non-isothermal differential scanning calori...The cure kinetics of diglycidyl ether of bisphenol A (DGEBA) with hyperbranched poly (3-hydroxyphenyl) phosphate(HHPP) as the curing agent was investigated by means of non-isothermal differential scanning calorimetry (DSC) at various heating rates. The results were compared with the corresponding results by using 1,3-dihydroxybenzene(DHB) as a model compound. The results show that HHPP can enhance the cure reaction of DGEBA, resulting in the decrease of the peak temperature of the curing curve as well as the decrease of the activation energy because of the flexible --P--O-- groups in the backbone of HHPP. However, both the activation energy of the cured polymer and the peak temperature of the curing curve are increased with DHB as a curing agent. The cure kinetics of the DGEBA/HHPP system was calculated by using the isoconversional method given by Malek. It was found that the two-parameter autocatalytic model(Sestak-Berggren equation) is the most adequate one to describe the cure kinetics of the studied System at various heating rates. The obtained non-isothermal DSC curves from the experimental data show the results being accordant with those theoretically calculated.展开更多
通过合理假设,从谢苗诺夫(Semenov)热爆炸理论和8个非等温动力学方程,导出了估算含能材料(EMs)热爆炸临界温度(Tb)的2个通式和它们的6个派生式。从EMs的非等温DSC曲线可获得DSC曲线偏离基线的起始温度(T0)、onset温度(Tei)和放热分解反...通过合理假设,从谢苗诺夫(Semenov)热爆炸理论和8个非等温动力学方程,导出了估算含能材料(EMs)热爆炸临界温度(Tb)的2个通式和它们的6个派生式。从EMs的非等温DSC曲线可获得DSC曲线偏离基线的起始温度(T0)、onset温度(Tei)和放热分解反应的动力学参数。由方程T0ior ei=T00 or e0+a1βi+a2βi2+…+aL-2βiL-2,i=1,2,…,L可得到T00和Te0值,随后用6个派生式可计算Tb值。对1,4,5,8-四硝基-1,4,5,8-四氮杂双呋咱[3,4-c:3′,4′-h]十氢化萘,1,4,5,8-四氮杂双呋咱[3,4-c:3′,4′-h]十氢化萘,1,3,4-三硝基咪唑烷酮[4,5-b]呋咱[3,4-e]哌嗪,咪唑烷酮[4,5-b]呋咱[3,4-e]哌嗪,1,3,4,8-四硝基咪唑烷酮[4,5-b]呋咱[3,4-e]哌嗪,1,4,5,8-四硝基-1,4,5,8-四氮杂萘呋咱[3,4-b]十氢化萘,1,3,5-三硝基-1,3,5-三氮杂呋咱[3,4-f]环庚烷,由6个派生式所得的Tb值甚接近。展开更多
文摘The cure kinetics of diglycidyl ether of bisphenol A (DGEBA) with hyperbranched poly (3-hydroxyphenyl) phosphate(HHPP) as the curing agent was investigated by means of non-isothermal differential scanning calorimetry (DSC) at various heating rates. The results were compared with the corresponding results by using 1,3-dihydroxybenzene(DHB) as a model compound. The results show that HHPP can enhance the cure reaction of DGEBA, resulting in the decrease of the peak temperature of the curing curve as well as the decrease of the activation energy because of the flexible --P--O-- groups in the backbone of HHPP. However, both the activation energy of the cured polymer and the peak temperature of the curing curve are increased with DHB as a curing agent. The cure kinetics of the DGEBA/HHPP system was calculated by using the isoconversional method given by Malek. It was found that the two-parameter autocatalytic model(Sestak-Berggren equation) is the most adequate one to describe the cure kinetics of the studied System at various heating rates. The obtained non-isothermal DSC curves from the experimental data show the results being accordant with those theoretically calculated.
文摘采用实时红外光谱(Real-Time FTIR)和非等温DSC法研究了促进剂2,4,6-三(二甲胺基甲基)苯酚(DMP-30),N,N-二甲基苄胺(BDMA)和三乙胺(TEA)对环氧树脂/聚硫醇体系固化的影响。利用n级模型和Malek法对体系DSC曲线进行分析,计算树脂体系的反应动力学参数。结果表明,DMP-30的催化效率高于BDMA和TEA。25℃下质量分数5%的DMP-30对环氧树脂/聚硫醇体系的促进作用最明显,20 min内环氧基的转化率达到85.2%。加入促进剂后的环氧树脂/聚硫醇体系可用双参数自催化模型来拟合,反应级数m,n分别为0.297和1.276,活化能为37.344 k J/mol。
基金National Natural Science Foundation of China(No.20573098)Science and Technology Foundation of the National Defence Key Laboratory of Propellant and Explosive Combustion of China(9140C3501050701)
文摘通过合理假设,从谢苗诺夫(Semenov)热爆炸理论和8个非等温动力学方程,导出了估算含能材料(EMs)热爆炸临界温度(Tb)的2个通式和它们的6个派生式。从EMs的非等温DSC曲线可获得DSC曲线偏离基线的起始温度(T0)、onset温度(Tei)和放热分解反应的动力学参数。由方程T0ior ei=T00 or e0+a1βi+a2βi2+…+aL-2βiL-2,i=1,2,…,L可得到T00和Te0值,随后用6个派生式可计算Tb值。对1,4,5,8-四硝基-1,4,5,8-四氮杂双呋咱[3,4-c:3′,4′-h]十氢化萘,1,4,5,8-四氮杂双呋咱[3,4-c:3′,4′-h]十氢化萘,1,3,4-三硝基咪唑烷酮[4,5-b]呋咱[3,4-e]哌嗪,咪唑烷酮[4,5-b]呋咱[3,4-e]哌嗪,1,3,4,8-四硝基咪唑烷酮[4,5-b]呋咱[3,4-e]哌嗪,1,4,5,8-四硝基-1,4,5,8-四氮杂萘呋咱[3,4-b]十氢化萘,1,3,5-三硝基-1,3,5-三氮杂呋咱[3,4-f]环庚烷,由6个派生式所得的Tb值甚接近。