A novel poly(1\|butene) was synthesized with η 5 \|pentamethylcyclopentadienyl\|tribenzyloxytitanium(Cp\+*Ti(OBz)\-3) and modified methylaluminoxane(MAO). The influence of various conditions (e.g., catalyst compositi...A novel poly(1\|butene) was synthesized with η 5 \|pentamethylcyclopentadienyl\|tribenzyloxytitanium(Cp\+*Ti(OBz)\-3) and modified methylaluminoxane(MAO). The influence of various conditions (e.g., catalyst composition, temperature, Al/Ti, pressure of monomer, and catalyst concentration) on the catalytic activity, molecular weight of the products were investigated in detail. It was found that the catalyst exhibited highest activity of 91 3kgPB/molTi·h at \%T\%=30℃, and Al/Ti(mol/mol)=200. The catalytic activity and molecular weight were sensitive to the TMA content in MAO and external TIBA. Catalytiac activity and molecular weight were decreased with increasing the content of TMA in MAO.External addition of TIBA can deactivated the catalyst. Molecular weight of the products was increased with decreasing temperature and Ti concentration. The catalyst had the highest activity at a Ti concentration of 1 0×10 -3 mol/L. The molecular weight of poly(1\|butene) is high, over one million by GPC method. The results showed that with this catalyst system, a high molecular weight poly(1\|butene) can be synthesized.展开更多
The effect of different sulfonation degree on properties of sulfonated syndiotactic polystyrene(S s PS) was investigated by 1H NMR, 13 C NMR,FTIR,DSC and WAXD.The results of 13 C NMR showed that a peak at δ =145 5 ap...The effect of different sulfonation degree on properties of sulfonated syndiotactic polystyrene(S s PS) was investigated by 1H NMR, 13 C NMR,FTIR,DSC and WAXD.The results of 13 C NMR showed that a peak at δ =145 5 appeared in all S s PS spectra,which proved that the syndiotactic structure of syndiotactic polystyrene( s PS) still existed in S s PS.With increasing degree of sulfonition,the chemical shifts of C 1 and C\|3 for sulfonated benzene ring turned out to be wider. 1 H NMR spectra showed that C\|3 for sulfonated benzene ring had a chemical shift of 7 66.FTIR spectra showed that sulfonic acid groups were introduced on the para position of benzene rings and with increasing sulfonation degree,the absorption strength of 612/1600 cm 1 ,834/1600cm -1 increased,but the absorption strength of 1078/1600cm -1 decreased.The absorption of ～1030cm -1 ,～1179cm -1 ,～1217cm -1 appeared when the sulfonation degree was higher that 6%. s PS and S s PS H 2 2 had absorption at 975 and 943cm -1 and also had double peaks around ～1175cm -1 ;DSC showed that with increasing sulfonation degree, the glass transition temperature increased, the melt temperature,crystallization temperature and crystallization degree decreased;S s PS couldn’t crystallize when sulfonation degree was higher that 6mol%;WAXD proved that s PS had the α and β crystal types, however,S s PS with 2 2% sulfonation degree only had the β crystal type, and S s PS with 6 1% sulfonation degree didn’t crystallize.展开更多
Pentamethylcyclopentadienyl) titanium triallyioxide[Cp *Ti(OCH 2-CH[CDS1]CH 2) 3] was used as the catalyst precursor for the synthesis of polybutene 1, methylalumiunoxane(MAO) as cocatalyst. The effects of the ratio o...Pentamethylcyclopentadienyl) titanium triallyioxide[Cp *Ti(OCH 2-CH[CDS1]CH 2) 3] was used as the catalyst precursor for the synthesis of polybutene 1, methylalumiunoxane(MAO) as cocatalyst. The effects of the ratio of n (Al) to n (Ti), polymerization temperature, and concentration of Ti on catalytic activity, molecular weight and chain structure were investigated in detail. The ether soluble fraction of the polybutene 1 was characterized with 13 C NMR, DSC, WAXD, and GPC. The results indicate that the polymers thus obtained are atactic and regioirregular, the weight average molecular weight of these polymers lies in the range of 3 0×10 5 to 7 0×10 5. Increasing the polymerization temperature can result in a decrease in the polymer molecular weight. But the molecular weight varies slightly with the ratio of n (Al) to n (Ti). The catalytic activity tends to decrease with the increase in polymerization temperature. was used as the catalyst precursor for the synthesis of polybutene 1, methylalumiunoxane(MAO) as cocatalyst. The effects of the ratio of n (Al) to n (Ti), polymerization temperature, and concentration of Ti on catalytic activity, molecular weight and chain structure were investigated in detail. The ether soluble fraction of the polybutene 1 was characterized with 13 C NMR, DSC, WAXD, and GPC. The results indicate that the polymers thus obtained are atactic and regioirregular, the weight average molecular weight of these polymers lies in the range of 3 0×10 5 to 7 0×10 5. Increasing the polymerization temperature can result in a decrease in the polymer molecular weight. But the molecular weight varies slightly with the ratio of n (Al) to n (Ti). The catalytic activity tends to decrease with the increase in polymerization temperature.展开更多
文摘A novel poly(1\|butene) was synthesized with η 5 \|pentamethylcyclopentadienyl\|tribenzyloxytitanium(Cp\+*Ti(OBz)\-3) and modified methylaluminoxane(MAO). The influence of various conditions (e.g., catalyst composition, temperature, Al/Ti, pressure of monomer, and catalyst concentration) on the catalytic activity, molecular weight of the products were investigated in detail. It was found that the catalyst exhibited highest activity of 91 3kgPB/molTi·h at \%T\%=30℃, and Al/Ti(mol/mol)=200. The catalytic activity and molecular weight were sensitive to the TMA content in MAO and external TIBA. Catalytiac activity and molecular weight were decreased with increasing the content of TMA in MAO.External addition of TIBA can deactivated the catalyst. Molecular weight of the products was increased with decreasing temperature and Ti concentration. The catalyst had the highest activity at a Ti concentration of 1 0×10 -3 mol/L. The molecular weight of poly(1\|butene) is high, over one million by GPC method. The results showed that with this catalyst system, a high molecular weight poly(1\|butene) can be synthesized.
文摘The effect of different sulfonation degree on properties of sulfonated syndiotactic polystyrene(S s PS) was investigated by 1H NMR, 13 C NMR,FTIR,DSC and WAXD.The results of 13 C NMR showed that a peak at δ =145 5 appeared in all S s PS spectra,which proved that the syndiotactic structure of syndiotactic polystyrene( s PS) still existed in S s PS.With increasing degree of sulfonition,the chemical shifts of C 1 and C\|3 for sulfonated benzene ring turned out to be wider. 1 H NMR spectra showed that C\|3 for sulfonated benzene ring had a chemical shift of 7 66.FTIR spectra showed that sulfonic acid groups were introduced on the para position of benzene rings and with increasing sulfonation degree,the absorption strength of 612/1600 cm 1 ,834/1600cm -1 increased,but the absorption strength of 1078/1600cm -1 decreased.The absorption of ～1030cm -1 ,～1179cm -1 ,～1217cm -1 appeared when the sulfonation degree was higher that 6%. s PS and S s PS H 2 2 had absorption at 975 and 943cm -1 and also had double peaks around ～1175cm -1 ;DSC showed that with increasing sulfonation degree, the glass transition temperature increased, the melt temperature,crystallization temperature and crystallization degree decreased;S s PS couldn’t crystallize when sulfonation degree was higher that 6mol%;WAXD proved that s PS had the α and β crystal types, however,S s PS with 2 2% sulfonation degree only had the β crystal type, and S s PS with 6 1% sulfonation degree didn’t crystallize.
文摘Pentamethylcyclopentadienyl) titanium triallyioxide[Cp *Ti(OCH 2-CH[CDS1]CH 2) 3] was used as the catalyst precursor for the synthesis of polybutene 1, methylalumiunoxane(MAO) as cocatalyst. The effects of the ratio of n (Al) to n (Ti), polymerization temperature, and concentration of Ti on catalytic activity, molecular weight and chain structure were investigated in detail. The ether soluble fraction of the polybutene 1 was characterized with 13 C NMR, DSC, WAXD, and GPC. The results indicate that the polymers thus obtained are atactic and regioirregular, the weight average molecular weight of these polymers lies in the range of 3 0×10 5 to 7 0×10 5. Increasing the polymerization temperature can result in a decrease in the polymer molecular weight. But the molecular weight varies slightly with the ratio of n (Al) to n (Ti). The catalytic activity tends to decrease with the increase in polymerization temperature. was used as the catalyst precursor for the synthesis of polybutene 1, methylalumiunoxane(MAO) as cocatalyst. The effects of the ratio of n (Al) to n (Ti), polymerization temperature, and concentration of Ti on catalytic activity, molecular weight and chain structure were investigated in detail. The ether soluble fraction of the polybutene 1 was characterized with 13 C NMR, DSC, WAXD, and GPC. The results indicate that the polymers thus obtained are atactic and regioirregular, the weight average molecular weight of these polymers lies in the range of 3 0×10 5 to 7 0×10 5. Increasing the polymerization temperature can result in a decrease in the polymer molecular weight. But the molecular weight varies slightly with the ratio of n (Al) to n (Ti). The catalytic activity tends to decrease with the increase in polymerization temperature.
