文献类型：期刊文献

中文题名：SBS加氢动力学研究

英文题名：KINETIC STUDIES OF SBS HYDROGENATION

作者：刘峰[1];洪良构[1];胡春圃[1];应圣康[1]

机构：[1]华东化工学院材料科学研究所,上海200237

年份：1992

卷号：15

期号：3

起止页码：160

中文期刊名：合成橡胶工业

外文期刊名：China Synthetic Rubber Industry

收录：CSTPCD;;Scopus;北大核心:【北大核心1992】；CSCD:【CSCD_E2011_2012】；

语种：中文

中文关键词：丁苯;改性;加氢;热塑性弹性体

外文关键词：thermoplastic elastomer ; styrene- butadiene - styrene block copolymer ; chemical modification ; hydrogenation kinetics

摘要：以环烷酸镍(Ni)和三异丁基铝(Al)为均相加氢催化剂,环己烷为溶剂,研究了丁二烯和苯乙烯三嵌段共聚物(SBS)的加氢动力学。结果表明,加氩速率与氢气压力的一次方成正比,与双键浓度无关;当Al/Ni=3(摩尔比),Ni浓度在2.5～7.5 mg/g SBS时,加氢速率达到最大值;利用Arrhenius关系求得恒压与变压下的表观加氢反应活化能分别为47.6 kJ/mol和35.8 kJ/mol。对加氢产物微观结构分析所得总加氢度为102.8％,表明该体系加氢效率高,选择性好。
The kinetics behavior of styrene - butadiene -styrene triblock copolymer (SBS) hydrogenation with cyclohexan as solvent and nickel naphthenate [Ni(Ⅱ)]-triisobutyl aluminium [Al(Ⅲ)] as homogeneous catalyst was studied . The results showed that the rate of hydrogenation was not related to the double bond concentration in SBS at constant hydrogen pressure (P). Figure 1 showed that the linear relationship between the zero rate constant (k0)and P was observed and the apparent first order rate constant (k) was 5.31×10-3L/ (inol·min·MPa).The hydrogenation rate was first order with respect to P over the range of temperatures studied here .while Al(Ⅲ)/Ni(Ⅱ)(molar ratio)was 3 . The value of k went through a maximum with the decrease of Ni(Ⅱ ) concentration . The value of k was highest for 2.5 - 7.5 mg Ni ( Ⅱ )/g SBS at Al(Ⅲ ) /Ni( Ⅱ )was 3 as shown in Figure 2 .When the ratios of Al(Ⅲ) /Ni( Ⅱ ) were 1.5 , 2.0 , 3.0 , 4.5 and 6.0 , the apparent first order rates were 0,0.02 ,0.26 ,0.12,and 0 (min-1) respectively at 2.5 mg Ni( Ⅱ )/g SBS .It was clear that Al( Ⅲ ) could not reduce Ni(Ⅱ ) to Ni(Ⅱ )or further reduce Ni (Ⅱ) to Ni ( 0) when the ratio of Al(Ⅲ) /Ni( Ⅱ ) was too small or too big . The apparent activation energies for hydrogenation were 47.6 kJ/mol or 35.8 kJ/mol at constant or unconstant pressure respectively .The GPC measurement exhibited that the SBS was neither degraded nor crosslinked during hydrogenation process .The hydrogenation conversions for SBS double bonds and styrene unites were characterized and found to be 98.2% and 4.6% respectively at moderate conditions , i.e., SBS concentration 2.5% (mass),Ni (Ⅱ) concentration 2.5 mg/g SBS ,Al (Ⅲ)/Ni(Ⅱ)3 (mol), hydrogenation temperature 80°C and hydrogenpressure 0.20 - 0.29 MPa . These values of hydrogenation conversions were very close to the total conversion of 103.6% as measured by the absorption of hydrogen in this system .