The Hofmann reactions of five polyacrylamides(PAM) with different molecular weights of two different concentrations were carried out to get better understanding the mechanisms of the reaction. The results show that th...The Hofmann reactions of five polyacrylamides(PAM) with different molecular weights of two different concentrations were carried out to get better understanding the mechanisms of the reaction. The results show that the maximum conversion of N chloroamides increased with molecular weights of PAM and got to the highest value at 9×10 4 , then decreased. The changes in maximum conversion of amino groups are similar to those of N chloroamides, the maximum content of amino group of PAM studied was 97%. However , the time to reach maximum conversion of amino groups appeared to be independent of the molecular weights in the range investigated.展开更多
以St g PAM/BA共聚物为原料,在碱性介质中与次氯酸钠作用,进行Hofmann降解反应,合成了St g PVM/BA。探讨了各种反应因素如聚合物体积分数、反应物配比、反应温度、反应时间等因素对胺化度的影响,确定了St g PVM/BA的适宜合成条件:聚合...以St g PAM/BA共聚物为原料,在碱性介质中与次氯酸钠作用,进行Hofmann降解反应,合成了St g PVM/BA。探讨了各种反应因素如聚合物体积分数、反应物配比、反应温度、反应时间等因素对胺化度的影响,确定了St g PVM/BA的适宜合成条件:聚合物体积分数为26%,n(-CONH2)∶n(NaOCl)∶n(NaOH)=1∶1∶20,反应温度θ=0℃,反应时间t=6h,此时胺化度达到最大值88.53%。经过Hofmann降解反应的聚合物分子中有极强的碱性基团氨基(-NH2),易与其他官能团反应。展开更多
文摘The Hofmann reactions of five polyacrylamides(PAM) with different molecular weights of two different concentrations were carried out to get better understanding the mechanisms of the reaction. The results show that the maximum conversion of N chloroamides increased with molecular weights of PAM and got to the highest value at 9×10 4 , then decreased. The changes in maximum conversion of amino groups are similar to those of N chloroamides, the maximum content of amino group of PAM studied was 97%. However , the time to reach maximum conversion of amino groups appeared to be independent of the molecular weights in the range investigated.
文摘以St g PAM/BA共聚物为原料,在碱性介质中与次氯酸钠作用,进行Hofmann降解反应,合成了St g PVM/BA。探讨了各种反应因素如聚合物体积分数、反应物配比、反应温度、反应时间等因素对胺化度的影响,确定了St g PVM/BA的适宜合成条件:聚合物体积分数为26%,n(-CONH2)∶n(NaOCl)∶n(NaOH)=1∶1∶20,反应温度θ=0℃,反应时间t=6h,此时胺化度达到最大值88.53%。经过Hofmann降解反应的聚合物分子中有极强的碱性基团氨基(-NH2),易与其他官能团反应。