The catalyst boron trifluoride etherate was used to catalyze the reaction of epoxy resin with polyethylene glycol (PEG), and the effect of the concentration of the catalyst on the reaction is studied. It is shown that...The catalyst boron trifluoride etherate was used to catalyze the reaction of epoxy resin with polyethylene glycol (PEG), and the effect of the concentration of the catalyst on the reaction is studied. It is shown that there exist two competitive reactions : I, self polymerization of epoxy resin via chain growth and II, copolymerization of epoxy resin with PEG via step growth. At high concentration of the catalyst reaction I dominates and reaction II is negligible. On the contrary, at low concentration of the catalyst, reaction II dominates and block copolymers are formed In the intermediate case, the two reactions are comparable with the result that a gel structure is obtained.展开更多
Waste packaging polyethylene（WPE） was used to modify raw asphalt by melt blending the components at 190 ℃ for 1 h in a simple mixer and subsequently machining them at 120 ℃ for 1 h in a highspeed shearing machine....Waste packaging polyethylene（WPE） was used to modify raw asphalt by melt blending the components at 190 ℃ for 1 h in a simple mixer and subsequently machining them at 120 ℃ for 1 h in a highspeed shearing machine.The effect of modification on the degree of the penetration,the softening point and the ductility of the asphalt was studied using fluorescent microscopy,infrared spectrometry,component changes and various other techniques.The experimental results showed that no chemical reactions took place in the components themselves（saturate,aromatic,asphaltene and resin） during the modifications.The softening point and penetration of the asphalt were found to be closely related to the resulting contents of the asphaltene,saturate and resin components.In addition,aromatics were identified as having the greatest impact on the ductility of the asphalt.展开更多
文摘The catalyst boron trifluoride etherate was used to catalyze the reaction of epoxy resin with polyethylene glycol (PEG), and the effect of the concentration of the catalyst on the reaction is studied. It is shown that there exist two competitive reactions : I, self polymerization of epoxy resin via chain growth and II, copolymerization of epoxy resin with PEG via step growth. At high concentration of the catalyst reaction I dominates and reaction II is negligible. On the contrary, at low concentration of the catalyst, reaction II dominates and block copolymers are formed In the intermediate case, the two reactions are comparable with the result that a gel structure is obtained.
基金Funded in part by the National Natural Science Foundation of China(Nos.51172180 and 51372200)the Program for New Century Excellent Talents in University of Ministry of Education of China(No.NCET-12-1045)+1 种基金the Local Service Program of Shaanxi Provincial Education Department(No.2013JC19)the Excellent Ph D Dissertation Foundation of XAUT(102-211208)
文摘Waste packaging polyethylene（WPE） was used to modify raw asphalt by melt blending the components at 190 ℃ for 1 h in a simple mixer and subsequently machining them at 120 ℃ for 1 h in a highspeed shearing machine.The effect of modification on the degree of the penetration,the softening point and the ductility of the asphalt was studied using fluorescent microscopy,infrared spectrometry,component changes and various other techniques.The experimental results showed that no chemical reactions took place in the components themselves（saturate,aromatic,asphaltene and resin） during the modifications.The softening point and penetration of the asphalt were found to be closely related to the resulting contents of the asphaltene,saturate and resin components.In addition,aromatics were identified as having the greatest impact on the ductility of the asphalt.
