甲基丙烯酸羟烷基酯与丙烯腈或丙烯酰胺共聚合的研究

测定了亲水性甲基丙烯酸羟烷基酯如HEMA、MHPMA分别与AN或AAM,在60℃不同溶剂中自由基聚合反应的竞聚率。AN(M_1)-HEMA(M_2)共单体,在DMSO或DMF溶剂以AIBN或KPS-IPA引发剂条件下共聚,用Kelen-Tüds法计算的竞聚率变化不大,r_1=0.22-0.25、r_2=0.97-1.05,说明在此均相溶液共聚中,所用的溶剂及引发剂对竞聚率的影响较小,这两种单体能很好共聚。但AAM-MHPMA或AAM-HEMA共单体时,r_1与r_2值相差很大,如前者r_1=0.0433、r_2=3.98,后者r_1=0.0535、r_2=1.89,说明不易共聚,共聚物中主要是MHPMA或HEMA组分。

COPOLYMERIZATION OF HYDROXYALKYL METHACRYLATE WITH ACRYLONITRILE OR ACRYLAMIDE

Reactivity ratios for hydroxy-containing monomers such as 2-hydroxyethyl me-thacrylate (HEMA) and 3--methoxy-2-hydroxypropyl methacrylate (MHPMA) with acrylonitrile (AN) or acrylamide (AAM) systems have been determined for radical co-polymerization at 60 ℃ in different solvents. The reactivity ratios computed by Kelen-Tudos and the Fineman-Ross and intersection graphitic methods have been compared. The values of r1=0.22-0.25, r2=0.97-1.05 for AN(M1)-HEMA (M2), in DMSO or DMF initiated either by a/obisisobutyronitrile (AIBN) or by potassium persufate (KPS)-iso-propyl alcohol (IPA), the reaction media and initiator would not play a pronounced effect. While, in AAM-MHPMA or AAM-HEMA, the values of reactivity ratios are as follows: r1=0.0433, r2=3.98 for the former case, and r1=0.0535, r2=1.89 for the later case, respectively. These distinct different values between r1 and rt showed that the AAM monomer is more difficultly enter to the copolymer composition than the AN monomer.