A novel UV-curable oligmer 1,4-cyclohexanedimethanol glycidyl ether acrylate（CHDMGEA） was synthesized by utilizing 1,4-cyclohexanedimethanol glycidyl ether（CHDMGE） and acrylic acid（AA） as starting materials, tri...A novel UV-curable oligmer 1,4-cyclohexanedimethanol glycidyl ether acrylate（CHDMGEA） was synthesized by utilizing 1,4-cyclohexanedimethanol glycidyl ether（CHDMGE） and acrylic acid（AA） as starting materials, triphenyl phosphine as catalyst and p-hydroxyanisole as inhibitor. The optimum synthetic conditions were that the concentration of triphenyl phosphine was 0.90% of reactants by weight, the concentration of p-hydroxyanisole was 0.20% of reactants by weight, the reaction temperature was 90-100 ℃, and the molar ratio of CHDMGE to AA was 0.5：1.1. The experimental results show that CHDMGEA is a kind of good UV-curable oligmer. The impact resistance of the UV-cured films with CHDMGEA as oligmer to prepare UV-curing coating was superior to that of the UV-cured films with bisphenol A diglycidyl ether diacrylate（BPGEA） as oligmer to prepare UV-curing coating.展开更多
The recycling of waste polyethylene terephthalate(PET),an extensively used polymer as plastic and fiber materials,has become an urgent topic due to the rapid generation and accumulation of plastic waste into the envir...The recycling of waste polyethylene terephthalate(PET),an extensively used polymer as plastic and fiber materials,has become an urgent topic due to the rapid generation and accumulation of plastic waste into the environment.Current chemical recycling approaches to depolymerize and convert PET into 1,4-cyclohexanedimethanol(CHDM),an important chemical in the production of advanced polyesters,predominantly use organic solvents,such as alcohols or dioxane.Herein,we developed an environmentally friendly and economically viable pathway for converting PET to CHDM using water as the solvent.In this process,PET is sequentially hydrolyzed in water,hydrogenated to 1,4-cyclohexane dicarboxylic acid(CHDA),and then reduced to CHDM.The PET conversion rate is self-enhanced in aqueous medium via acid-catalyzed hydrolysis by the generated CHDA intermediate.A Pd-based catalyst(e.g.,Pd/C)selectively hydrogenates the arene ring of the PET monomer,terephthalic acid intermediate,and a Ru-Sn/C bimetallic catalyst reduces its COOH to CH_(2)OH group.At optimized reaction conditions,a complete conversion of PET and 80.1%yield of CHDM are obtained.Alternatively,this approach can also efficiently produce CHDA from PET,with a yield up to 86.4%.展开更多
采用Co_(3)O_(4)吸附脱除模拟柴油中的喹啉、吡啶或苯胺,考察了最佳吸附温度、吸附时间等条件,同时进行了吸附热力学和动力学研究;基于第一性原理对Co_(3)O_(4)晶胞进行相分析,对3种氮化物进行最高占据分子轨道(HOMO)-最低未占据分子轨...采用Co_(3)O_(4)吸附脱除模拟柴油中的喹啉、吡啶或苯胺,考察了最佳吸附温度、吸附时间等条件,同时进行了吸附热力学和动力学研究;基于第一性原理对Co_(3)O_(4)晶胞进行相分析,对3种氮化物进行最高占据分子轨道(HOMO)-最低未占据分子轨道(LUMO)分析,计算了吸附构型的吸附能和最稳定吸附构型的Mulliken电荷转移与电子密度。结果表明:在15 mL模拟柴油中加入0.6 g Co_(3)O_(4),苯胺、吡啶、喹啉的最佳吸附温度分别为20、20和30℃,最佳吸附时间分别为30、30、40 min,吸附容量由大到小顺序均为苯胺>吡啶>喹啉。热力学与动力学分析表明,喹啉、吡啶、苯胺的吸附均更符合多分子层吸附的Freundlich模型和准二级动力学方程。HOMO-LUMO分析结果表明,Co_(3)O_(4)为电子接受体,3种氮化物为电子给予体,Co_(3)O_(4)对喹啉、吡啶的配位吸附结构最稳定,对苯胺的π络合吸附最稳定。电荷转移计算表明,苯胺、吡啶、喹啉向Co_(3)O_(4)团簇转移的电荷数分别为0.423、0.394、0.368,说明Co_(3)O_(4)吸附3种氮化物的吸附能力大小为苯胺>吡啶>喹啉;电子密度图结果表明,最稳定吸附结构中Co_(3)O_(4)与3种氮化物均形成了化学键。展开更多
基金Funded by the Natural Science Foundation of Jiangxi Province(20142BAB206029)
文摘A novel UV-curable oligmer 1,4-cyclohexanedimethanol glycidyl ether acrylate（CHDMGEA） was synthesized by utilizing 1,4-cyclohexanedimethanol glycidyl ether（CHDMGE） and acrylic acid（AA） as starting materials, triphenyl phosphine as catalyst and p-hydroxyanisole as inhibitor. The optimum synthetic conditions were that the concentration of triphenyl phosphine was 0.90% of reactants by weight, the concentration of p-hydroxyanisole was 0.20% of reactants by weight, the reaction temperature was 90-100 ℃, and the molar ratio of CHDMGE to AA was 0.5：1.1. The experimental results show that CHDMGEA is a kind of good UV-curable oligmer. The impact resistance of the UV-cured films with CHDMGEA as oligmer to prepare UV-curing coating was superior to that of the UV-cured films with bisphenol A diglycidyl ether diacrylate（BPGEA） as oligmer to prepare UV-curing coating.
基金supported by the National Natural Science Foundation of China(22472059,22302069)the Natural Science Foundation of Shanghai(23ZR1418800)the Fundamental Research Funds for the Central Universities(YBNL TS202307)。
文摘The recycling of waste polyethylene terephthalate(PET),an extensively used polymer as plastic and fiber materials,has become an urgent topic due to the rapid generation and accumulation of plastic waste into the environment.Current chemical recycling approaches to depolymerize and convert PET into 1,4-cyclohexanedimethanol(CHDM),an important chemical in the production of advanced polyesters,predominantly use organic solvents,such as alcohols or dioxane.Herein,we developed an environmentally friendly and economically viable pathway for converting PET to CHDM using water as the solvent.In this process,PET is sequentially hydrolyzed in water,hydrogenated to 1,4-cyclohexane dicarboxylic acid(CHDA),and then reduced to CHDM.The PET conversion rate is self-enhanced in aqueous medium via acid-catalyzed hydrolysis by the generated CHDA intermediate.A Pd-based catalyst(e.g.,Pd/C)selectively hydrogenates the arene ring of the PET monomer,terephthalic acid intermediate,and a Ru-Sn/C bimetallic catalyst reduces its COOH to CH_(2)OH group.At optimized reaction conditions,a complete conversion of PET and 80.1%yield of CHDM are obtained.Alternatively,this approach can also efficiently produce CHDA from PET,with a yield up to 86.4%.
文摘采用Co_(3)O_(4)吸附脱除模拟柴油中的喹啉、吡啶或苯胺,考察了最佳吸附温度、吸附时间等条件,同时进行了吸附热力学和动力学研究;基于第一性原理对Co_(3)O_(4)晶胞进行相分析,对3种氮化物进行最高占据分子轨道(HOMO)-最低未占据分子轨道(LUMO)分析,计算了吸附构型的吸附能和最稳定吸附构型的Mulliken电荷转移与电子密度。结果表明:在15 mL模拟柴油中加入0.6 g Co_(3)O_(4),苯胺、吡啶、喹啉的最佳吸附温度分别为20、20和30℃,最佳吸附时间分别为30、30、40 min,吸附容量由大到小顺序均为苯胺>吡啶>喹啉。热力学与动力学分析表明,喹啉、吡啶、苯胺的吸附均更符合多分子层吸附的Freundlich模型和准二级动力学方程。HOMO-LUMO分析结果表明,Co_(3)O_(4)为电子接受体,3种氮化物为电子给予体,Co_(3)O_(4)对喹啉、吡啶的配位吸附结构最稳定,对苯胺的π络合吸附最稳定。电荷转移计算表明,苯胺、吡啶、喹啉向Co_(3)O_(4)团簇转移的电荷数分别为0.423、0.394、0.368,说明Co_(3)O_(4)吸附3种氮化物的吸附能力大小为苯胺>吡啶>喹啉;电子密度图结果表明,最稳定吸附结构中Co_(3)O_(4)与3种氮化物均形成了化学键。
