摘要
以甲基丙烯酸甲酯(MMA)和对氯甲基苯乙烯(VBC)为单体,偶氮二异丁脒盐酸盐(AIBA)为引发剂,通过乳液聚合制备温敏聚合物材料P(MMA-co-VBCx%).通过接枝反应将玫瑰红(RB)引入到P(MMA-co-VBCx%)中,得到上临界溶解温度(UCST)型准均相聚合物催化剂P(MMA-co-VBCx%)-RBy%.使用1 H NMR、FTIR和GPC表征了P(MMA-co-VBCx%)和P(MMA-co-VBCx%)-RBy%的结构,分析了温敏材料和准均相催化剂的UCST行为,并以N-芳基四氢异喹啉(THIQ)和硝基甲烷(NM)的交叉脱氢偶联反应(CDC)为模型,研究了准均相催化剂的催化性能和回用性能.结果表明,P(MMA-co-VBCx%)的 Tcp(浊点)随 VBC 含量增加而下降,准均相催化剂 P(MMA-co-VBCx%)-RBy%的Tcp随RB含量增加而下降,在乙醇-水体积比为 4∶1时,两类聚合物的响应温度位于 40～60℃;P(MMA-co-VBCx%)-RBy%具有较好的溶解-析出性能,溶解-析出循环5 次时,回收率>90%;在催化THIQ和NM的反应中,P(MMA-co-VBCx%)-RBy%的催化活性与均相催化剂RB相当,且适用于其他衍生物的反应,降温可回收催化剂,重复使用5 次,催化活性无明显下降.
Abstract
Temperature-sensitive polymer materials P(MMA-co-VBCx%)were successfully prepared by emulsion polymerization using methyl methacrylate(MMA)and 1-(chloromethyl)-4-vinylbenzene(VBC)as monomers and 2,2'-azobis(2-methylpropionamidine)dihydrochloride(AIBA)as initiator.Rose Ben-gal(RB)was introduced into P(MMA-co-VBCx%)by grafting reaction to obtain UCST(upper critical solubility temperature)type quasi-homogeneous polymerization catalyst P(MMA-co-VBCx%)-RBy%.The structures of P(MMA-co-VBCx%)and P(MMA-co-VBCx%)-RBy%were characterized using 1 H NMR,FTIR and GPC;the UCST behaviors of the temperature-sensitive materials and Quasi-homogeneous cata-lysts were analyzed;and the cross-dehydrogenation coupling reaction(CDC)of N-aryl-tetrahydroisoquino-line(THIQ)and nitromethane(NM)was used as a model.The catalytic performance and reuse perform-ance of quasi-homogeneous catalysts were investigated.The results showed that the Tcp(cloud point)of P(MMA-co-VBCx%)decreased with increasing VBC content,and the Tcp of Quasi-homogeneous catalysts P(MMA-co-VBCx%)-RBy%decreased with increasing RB content.And the response temperatures of both types of polymers were located at40～60℃at the ethanol-water with a volume ratio of 4∶1;P(MMA-co-VBCx%)-RBy%has good dissolution-dissolution performance,and the recovery is greater than 90%at 5 dissolution-dissolution cycles;the catalytic activity of P(MMA-co-VBCx%)-RBy%is comparable to that of the homogeneous catalyst RB in catalyzing the reactions of THIQ and NM,and is applicable to the reac-tions of other derivatives.The catalyst can be recovered by lowering the temperature and reused 5 times with no significant decrease in catalytic activity.
基金项目
山东省自然科学基金资助项目(ZR2021ME251)
中国博士后科学基金资助项目(2021M690599)
维普
万方数据