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A series of 3-arm ABC and AA’B and 4-arm ABCD,AA’BC and AA′A″B heteroarm star polymers comprising one poly(4-methylphenyl vinyl sulfoxide) segment and other segments such as polystyrene,poly(α-methylstyrene), poly(4-methoxystyrene) and poly(4-trimethylsilylstyrene) were synthesized by living anionic polymerization based on diphenylethylene(DPE) chemistry.The DPE-functionalized polymers were synthesized by iterative methodology,and the objective star polymers were prepared by two distinct methodologies based on anionic polymerization using DPE-functionalized polymers.The first methodology involves an addition reaction of living anionic polymer with excess DPE-functionalized polymer and a subsequent living anionic polymerization of 4-methylphenyl vinyl sulfoxide(MePVSO) initiated from the in situ formed polymer anion with two or three polymer segments.The second methodology comprises an addition reaction of DPE-functionalized polymer with excess sec-BuLi and a following anionic polymerization of MePVSO initiated from the in situ formed polymer anion and 3-methyl-1,1-diphenylpentyl anion as well.Both approaches could afford the target heteroarm star polymers with predetermined molecular weight,narrow molecular weight distribution (M_w/M_n<1.03) and desired composition,evidenced by SEC,~1H-NMR and SLS analyses.These polymers can be used as model polymers to investigate structure-property relationships in heteroarm star polymers.
A series of 3-arm ABC and AA’B and 4-arm ABCD, AA’BC and AA’A "B heteroarm star polymers comprising one poly (4-methylphenyl vinyl sulfoxide) segment and other segments such as polystyrene, poly poly (4-methoxystyrene) and poly (4-trimethylsilylstyrene) were synthesized by living anionic polymerization based on diphenylethylene (DPE) chemistry. The DPE-functionalized polymers were synthesized by iterative methodology, and the objective star polymers were prepared by two distinct methodologies based on anionic polymerization using DPE-functionalized polymers. first ratio furnished an addition reaction of living anionic polymer with excess DPE-functionalized polymer and a subsequent living anionic polymerization of 4-methylphenyl vinyl sulfoxide (MePVSO) initiated from the in situ formed polymer anion with two or three polymer segments. The second methodology includes an addition reaction of DPE-functionalized polymer with excess sec-BuLi and a following anionic anionic merization of MePVSO initiated from the in situ formed polymer anion and 3-methyl-1,1-diphenylpentyl anion as well. This approach could afford the target heteroarm star polymers with a predetermined molecular weight, narrow molecular weight distribution (M_w / M_n <1.03) and desired composition, evidenced by SEC, ~ 1H-NMR and SLS analyzes. These polymers can be used as model polymers to investigate structure-property relationships in heteroarm star polymers.