Diels-Alder addition of dicyclopentadiene and cyclopentadiene in polar solvents has been studied to produce tricyclopentadiene（TCPD） that is a potential high-density fuel precursor. GC and MS analysis shows that the...Diels-Alder addition of dicyclopentadiene and cyclopentadiene in polar solvents has been studied to produce tricyclopentadiene（TCPD） that is a potential high-density fuel precursor. GC and MS analysis shows that the adducts contain two isomers, namely exo- and endo-TCPD. Theoretical simulation shows that although the transition state of endo-TCPD has a lower activation energy, exo-TCPD is thermodynamically preferred. Polar solvents can accelerate the reaction rate and improve the exo/endo ratio of TCPD because the transition state of exo-TCPD has a higher polarity than that of endo-TCPD. The solvent effect follows the order of polarity： benzyl methanol〉cyclohexanone〉toluene. The conversion rises when the temperature ranges from 120 to 150 ℃, but the selectivity of TCPD slightly decreases. Increasing the pressure can improve the conversion but the exo/endo ratio of TCPD is unchanged. The apparent kinetics in different solvents was determined via nonlinear regression. The activation energies are 99.47, 101.15, and 107.32 kJ/mol for benzyl methanol, cyclohexanone, and toluene, respectively. The optimal reaction conditions are as follows： benzyl methanol as solvent, temperature 150 ℃, and pressure 900 kPa. After an 11-hour reaction, a conversion of 58.0%, a TCPD selectivity of 95.7%, and an exo/endo ratio of 1/5.3 has been obtained.展开更多
The copolymerization of ethylene with dieyclopentadiene （DCP） in the presence of a constrained geometry tetramethylcyclopentadi-enyl-phenoxytitanium catalyst [ 2,4-＇ Bu2-6-（ 2,3,4,5-Me4 -Cp ） -PhO ] TICl2, combin...The copolymerization of ethylene with dieyclopentadiene （DCP） in the presence of a constrained geometry tetramethylcyclopentadi-enyl-phenoxytitanium catalyst [ 2,4-＇ Bu2-6-（ 2,3,4,5-Me4 -Cp ） -PhO ] TICl2, combined with AI（ iBu）3/Ph3C^＋ B（ CsF5 ）4^- cocatalyst system was studied. The copolymers that were formed were characterized by ＇ H and ,3 C NMR, differential scanning calorimetry （ DSC）, SEM, and X-ray diffraction （XRD） analyses. The re- suits of the analysis indicate that the copolymers of ethylene with dicyclopentadiene are amorphous and display two or more melting temperatures in their DSC diagrams. Moreover, the morphologies of the copolymers are quite different from that of polyethylenes.展开更多
A novel novolac curing agent containing both naphthalene and dicyclopentadiene (DCPD) moieties was prepared to produce a highly heat-resistant cured polymer network. The chemical structure was characterized using Four...A novel novolac curing agent containing both naphthalene and dicyclopentadiene (DCPD) moieties was prepared to produce a highly heat-resistant cured polymer network. The chemical structure was characterized using Fourier transform infrared spectroscopy, nuclear magnetic resonance, mass spectrometry, and gel permeation chro-matography analyses. The thermal properties of the resulting polymer from diglycidyl ether of bisphenol A epoxy resin cured with the novel curing agent were evaluated using dynamic mechanical thermal analysis and thermogra-vimetric analysis. Compared with the conventional curing agent, the resulting polymer cured with naphtha-lene/DCPD navolac shows considerable improvement in heat resistant properties such as higher glass transition temperature (Tg) and thermal stability. The result also shows better moisture resistance because of the hydrophobic nature of naphthalene/DCPD structure.展开更多
Novel catalytic systems for the Rh‐catalyzed hydroformylation of dicyclopentadiene have been developed using tris‐H8‐binaphthyl monophosphite as ligands containing different ester substituents at the 2’‐binaphthy...Novel catalytic systems for the Rh‐catalyzed hydroformylation of dicyclopentadiene have been developed using tris‐H8‐binaphthyl monophosphite as ligands containing different ester substituents at the 2’‐binaphthyl position(OCOMe,OCOPh,OCOAdamantyl and OCOPhCl).The catalysts exhibited high activity(S/C=4000,TON=3286)with good to excellent selectivity towards dialdehydes.Remarkably,the Rh(I)complex bearing the ligands with chlorophenyl ester substituents led to 99.9%conversion and 98.7%selectivity for dialdehydes under relatively mild conditions(6 MPa,120°C).展开更多
Endo-dicyclopentadiene was isomerized to exo-isomer by thermal treatment at evaluated temperature and pressure. The reaction temperature and pressure are key factors for this novel isomerization. This result may have ...Endo-dicyclopentadiene was isomerized to exo-isomer by thermal treatment at evaluated temperature and pressure. The reaction temperature and pressure are key factors for this novel isomerization. This result may have great potential for practical application.展开更多
Ligand effect of the catalytic system WCl6-Et2AlCl for ring opening metathesis polymerization (ROMP) of dicyclopentadiene (DCPD) was investigated. The experimental results show that adding sterically hindered phenol-2...Ligand effect of the catalytic system WCl6-Et2AlCl for ring opening metathesis polymerization (ROMP) of dicyclopentadiene (DCPD) was investigated. The experimental results show that adding sterically hindered phenol-2. 6-di-tert-butylcresylol(DTBC) in the catalytic system not only can obviously increase the monomer conversion of polymerization but also improve the mechanical properties, such as notched impact strength (NIS), tensile strength (TS) ect. 5 of the synthesized polyicycolpentadiene (PDCPD). A similar effect can be observed by using a sterically hindered polymeric phenol - linear phenol formaldehyde resin (LPF) as a ligand.展开更多
Dicyclopentadiene was polymerized by reaction injection molding (RIM) using a catalyst system based on molybdenum (V) chloride and anhydrous aluminum chloride and triethylaluminum. The effect of the reaction temperatu...Dicyclopentadiene was polymerized by reaction injection molding (RIM) using a catalyst system based on molybdenum (V) chloride and anhydrous aluminum chloride and triethylaluminum. The effect of the reaction temperature on the polymer network and the type of the polymerization were discussed.展开更多
基金Supported by Fundamental Research Project of Commission of ScienceTechnology and Industry for National Defense of China(NoA1420060192)
文摘Diels-Alder addition of dicyclopentadiene and cyclopentadiene in polar solvents has been studied to produce tricyclopentadiene（TCPD） that is a potential high-density fuel precursor. GC and MS analysis shows that the adducts contain two isomers, namely exo- and endo-TCPD. Theoretical simulation shows that although the transition state of endo-TCPD has a lower activation energy, exo-TCPD is thermodynamically preferred. Polar solvents can accelerate the reaction rate and improve the exo/endo ratio of TCPD because the transition state of exo-TCPD has a higher polarity than that of endo-TCPD. The solvent effect follows the order of polarity： benzyl methanol〉cyclohexanone〉toluene. The conversion rises when the temperature ranges from 120 to 150 ℃, but the selectivity of TCPD slightly decreases. Increasing the pressure can improve the conversion but the exo/endo ratio of TCPD is unchanged. The apparent kinetics in different solvents was determined via nonlinear regression. The activation energies are 99.47, 101.15, and 107.32 kJ/mol for benzyl methanol, cyclohexanone, and toluene, respectively. The optimal reaction conditions are as follows： benzyl methanol as solvent, temperature 150 ℃, and pressure 900 kPa. After an 11-hour reaction, a conversion of 58.0%, a TCPD selectivity of 95.7%, and an exo/endo ratio of 1/5.3 has been obtained.
基金Supported by the National Natural Science Foundation of China(Nos 20674024 and 20374023)
文摘The copolymerization of ethylene with dieyclopentadiene （DCP） in the presence of a constrained geometry tetramethylcyclopentadi-enyl-phenoxytitanium catalyst [ 2,4-＇ Bu2-6-（ 2,3,4,5-Me4 -Cp ） -PhO ] TICl2, combined with AI（ iBu）3/Ph3C^＋ B（ CsF5 ）4^- cocatalyst system was studied. The copolymers that were formed were characterized by ＇ H and ,3 C NMR, differential scanning calorimetry （ DSC）, SEM, and X-ray diffraction （XRD） analyses. The re- suits of the analysis indicate that the copolymers of ethylene with dicyclopentadiene are amorphous and display two or more melting temperatures in their DSC diagrams. Moreover, the morphologies of the copolymers are quite different from that of polyethylenes.
文摘A novel novolac curing agent containing both naphthalene and dicyclopentadiene (DCPD) moieties was prepared to produce a highly heat-resistant cured polymer network. The chemical structure was characterized using Fourier transform infrared spectroscopy, nuclear magnetic resonance, mass spectrometry, and gel permeation chro-matography analyses. The thermal properties of the resulting polymer from diglycidyl ether of bisphenol A epoxy resin cured with the novel curing agent were evaluated using dynamic mechanical thermal analysis and thermogra-vimetric analysis. Compared with the conventional curing agent, the resulting polymer cured with naphtha-lene/DCPD navolac shows considerable improvement in heat resistant properties such as higher glass transition temperature (Tg) and thermal stability. The result also shows better moisture resistance because of the hydrophobic nature of naphthalene/DCPD structure.
文摘Novel catalytic systems for the Rh‐catalyzed hydroformylation of dicyclopentadiene have been developed using tris‐H8‐binaphthyl monophosphite as ligands containing different ester substituents at the 2’‐binaphthyl position(OCOMe,OCOPh,OCOAdamantyl and OCOPhCl).The catalysts exhibited high activity(S/C=4000,TON=3286)with good to excellent selectivity towards dialdehydes.Remarkably,the Rh(I)complex bearing the ligands with chlorophenyl ester substituents led to 99.9%conversion and 98.7%selectivity for dialdehydes under relatively mild conditions(6 MPa,120°C).
文摘Endo-dicyclopentadiene was isomerized to exo-isomer by thermal treatment at evaluated temperature and pressure. The reaction temperature and pressure are key factors for this novel isomerization. This result may have great potential for practical application.
文摘Ligand effect of the catalytic system WCl6-Et2AlCl for ring opening metathesis polymerization (ROMP) of dicyclopentadiene (DCPD) was investigated. The experimental results show that adding sterically hindered phenol-2. 6-di-tert-butylcresylol(DTBC) in the catalytic system not only can obviously increase the monomer conversion of polymerization but also improve the mechanical properties, such as notched impact strength (NIS), tensile strength (TS) ect. 5 of the synthesized polyicycolpentadiene (PDCPD). A similar effect can be observed by using a sterically hindered polymeric phenol - linear phenol formaldehyde resin (LPF) as a ligand.
文摘Dicyclopentadiene was polymerized by reaction injection molding (RIM) using a catalyst system based on molybdenum (V) chloride and anhydrous aluminum chloride and triethylaluminum. The effect of the reaction temperature on the polymer network and the type of the polymerization were discussed.
