SYNTHESIS AND CHARACTERIZATION OF BLOCK POLYMER OF ALTERNATING COPOLYMERS

Block polymer of alternating copolymers, poly[(ST-a-MA)-b(IP-a-MMA)-b-(ST-a-MA)](I), has been synthesized in the presence of AlEt_(1.5)Cl_(1.5),by using Mn_2(CO)_(10)/CBr_4. initiation system.The GPC results indicate that there is no unreacted prepolymer in I purified by precipitation andfractionation. The study of NMR shows that every block of polymer I has alternating structure. The dynamicmechanical properties of I measured by torsional braid method indicate that the polymer has two T_g s,being 38 and 75℃, respectively. The transmission electron micrographs of I show they have two phasestructure and the domain size increases with increasing molecular weight of hard block.     

交替共聚物的嵌段聚合物的合成与表征

以Mn_2(CO)_(10)—CBr_4为引发剂,在AlEt_(1.5) Cl_(1.5)存在下,合成了交替共聚物的嵌段聚合物,Poly[(St-a-MA)-b-(IP-a-MMA)-b-(St-a-MA)]。NMR研究表明该嵌段聚合物各段都具有交替结构。扭辫法测定动态力学性能显示有两个T_g,分别为38℃和75℃。透射电镜研究表明,该聚合物具有两相结构。微区随硬段分子量增大而增大。