The poly(vinylpyridine)(PVP) based(co)polymers are of particular interest in materials science, due to their multifunctionality and diverse applications. So far, there is no report on the sequence-regulated copolymeri...The poly(vinylpyridine)(PVP) based(co)polymers are of particular interest in materials science, due to their multifunctionality and diverse applications. So far, there is no report on the sequence-regulated copolymerization of vinylpyridines(VPs) and methacrylate monomer in one-step manner yet. Here we designed and synthesized a series of guanidine phosphines as Lewis base(LB), which is combined with bulky organoaluminium to construct Lewis pairs(LPs) for polymerization of VPs. The living/controlled polymerization of 4-vinylpyridine(4-VP) or 2-vinylpyridine(2-VP) can be accomplished with remarkable efficiency by such Lewis pair polymerization(LPP), furnishing polymers with high molecular weight(up to 288 kg/mol) and narrow molecular weight distribution(as low as 1.17). Mechanistic studies reveal the interaction of LPs and formation of zwitterionic intermediates, providing solid evidences to support the proposed polymerization mechanism. More importantly, by simply adjusting the LA dosage, this LPP strategy realizes the unprecedented control over the sequence regulation of 2-VP-based copolymers from gradient to block in one-step manner, regardless of the monomer ratio, which greatly expands the versatility of the LPP.展开更多
Chemoselective,living/controlled polymerizations of allyl methacrylate(AMA) and vinyl methacrylate(VMA) with/without methyl methacrylate(MMA) by using the phosphonium ylide/organoaluminum based Lewis pairs(LPs) have b...Chemoselective,living/controlled polymerizations of allyl methacrylate(AMA) and vinyl methacrylate(VMA) with/without methyl methacrylate(MMA) by using the phosphonium ylide/organoaluminum based Lewis pairs(LPs) have been realized.The P-ylide-2/AIMe(BHT)_(2)(Pylide-2=Ph_(3)P=CHMe and BHT=2,6-iBu_(2)-4-MeC_(6)H_(2)O) was demonstrated to be superior by which homopolymers PAMAs(M_(n)=27.6-111.5kg/mol and ■=1.14-1.25) and PVMAs(M_(n)=28.4-78.4 kg/mol and ■=1.12-1.18) and block copolymers PMMA-b-PAMA,PAMA-b-PVMA,PAMA-bPMMA,PMMA-b-PAMA-b-PMMA,PAMA-b-PMMA-b-PAMA,and PAMA-b-PVMA-b-PAMA were synthesized.In the polymerizations,all of the monomers were reacted by the conjugated ester vinyl groups leaving intactly the nonconjugated acryloxy groups.The pendant acryloxy groups attached to the main chain enable further to post-functionalization by the AIBN-induced radical "thiol-ene" reaction using PhCH_(2)SH.The thiolether side group-containing polymers PAMA-SCH_(2)Ph and PAMA-SCH_(2)Ph-b-PMMA-b-PAMA-SCH_(2)Ph were thus prepared.展开更多
Block copolymers have aroused much interest,and their application has been rapidly expanded.In recent years,our group has committed to exploring synthesis and self-assembly of block copolymers.We have designed and syn...Block copolymers have aroused much interest,and their application has been rapidly expanded.In recent years,our group has committed to exploring synthesis and self-assembly of block copolymers.We have designed and synthesized several new thermo-responsive polymers and photo-responsive polymers by living/controlled radical polymerization(LCRP)and investigated their stimuli-responsive properties.Aiming at convenient and efficient synthesis of block copolymer nano-assemblies,we have developed several methods based on polymerization-induced self-assembly(PISA).Herein,we give a short summary of our research in these years.The aim of this account is to stimulate innovative synthesis strategies of block copolymer nano-assemblies,and promote more scientific research cooperation to face the exciting opportunities and challenges encountered in block copolymers.展开更多
Four armed star shaped copolymer of methyl methacrylate(MMA)/ N cyclohexylmaleimide(NCMI) with heat resistance was synthesized by atom transfer radical copolymerization with the CuBr/bpy catalyst in anisole, initiated...Four armed star shaped copolymer of methyl methacrylate(MMA)/ N cyclohexylmaleimide(NCMI) with heat resistance was synthesized by atom transfer radical copolymerization with the CuBr/bpy catalyst in anisole, initiated by tetra(bromomethyl)benzene. A linear plot of ln( 0/) versus reaction time was obtained by using anisole as solvent. In contrast, the use of cyclohexanone as solvent results in that the rate of copolymerization decreases as the reaction proceeds. Using anisole as the solvent in the copolymerization, the molecular weight of the resultant copolymer(measured by triple detection SEC) increased linearly with the increase of conversion, and the molecular weight distributions are narrow. The glass transition temperature of the resultant copolymer was higher than that of the pure PMMA. The synthesized four armed star copolymer was used as macroinitiator for the cationic polymerization of 2 methyl 2 oxazoline to yield star shaped poly(MMA co NCMI)/poly(2 methyl 2 oxazoline) block copolymers. The approximately linear increase of the molecular weight with the increase of reaction time and the low molecular weight distribution demonstrate a controlled chain extension reaction.展开更多
基金supported by the National Natural Science Foundation of China (22225104, 92356302 and 22071077)China Postdoctoral Science Foundation (2022TQ0115 and 2022M711297)。
文摘The poly(vinylpyridine)(PVP) based(co)polymers are of particular interest in materials science, due to their multifunctionality and diverse applications. So far, there is no report on the sequence-regulated copolymerization of vinylpyridines(VPs) and methacrylate monomer in one-step manner yet. Here we designed and synthesized a series of guanidine phosphines as Lewis base(LB), which is combined with bulky organoaluminium to construct Lewis pairs(LPs) for polymerization of VPs. The living/controlled polymerization of 4-vinylpyridine(4-VP) or 2-vinylpyridine(2-VP) can be accomplished with remarkable efficiency by such Lewis pair polymerization(LPP), furnishing polymers with high molecular weight(up to 288 kg/mol) and narrow molecular weight distribution(as low as 1.17). Mechanistic studies reveal the interaction of LPs and formation of zwitterionic intermediates, providing solid evidences to support the proposed polymerization mechanism. More importantly, by simply adjusting the LA dosage, this LPP strategy realizes the unprecedented control over the sequence regulation of 2-VP-based copolymers from gradient to block in one-step manner, regardless of the monomer ratio, which greatly expands the versatility of the LPP.
基金financially supported by the National Natural Science Foundation of China (Nos. 21972112 and 22225104)China Postdoctoral Science Foundation (Nos. 2022TQ0115 and 2022M711297)。
文摘Chemoselective,living/controlled polymerizations of allyl methacrylate(AMA) and vinyl methacrylate(VMA) with/without methyl methacrylate(MMA) by using the phosphonium ylide/organoaluminum based Lewis pairs(LPs) have been realized.The P-ylide-2/AIMe(BHT)_(2)(Pylide-2=Ph_(3)P=CHMe and BHT=2,6-iBu_(2)-4-MeC_(6)H_(2)O) was demonstrated to be superior by which homopolymers PAMAs(M_(n)=27.6-111.5kg/mol and ■=1.14-1.25) and PVMAs(M_(n)=28.4-78.4 kg/mol and ■=1.12-1.18) and block copolymers PMMA-b-PAMA,PAMA-b-PVMA,PAMA-bPMMA,PMMA-b-PAMA-b-PMMA,PAMA-b-PMMA-b-PAMA,and PAMA-b-PVMA-b-PAMA were synthesized.In the polymerizations,all of the monomers were reacted by the conjugated ester vinyl groups leaving intactly the nonconjugated acryloxy groups.The pendant acryloxy groups attached to the main chain enable further to post-functionalization by the AIBN-induced radical "thiol-ene" reaction using PhCH_(2)SH.The thiolether side group-containing polymers PAMA-SCH_(2)Ph and PAMA-SCH_(2)Ph-b-PMMA-b-PAMA-SCH_(2)Ph were thus prepared.
基金support by the National Natural Science Foundation of China(No.21931003)is gratefully acknowledged.
文摘Block copolymers have aroused much interest,and their application has been rapidly expanded.In recent years,our group has committed to exploring synthesis and self-assembly of block copolymers.We have designed and synthesized several new thermo-responsive polymers and photo-responsive polymers by living/controlled radical polymerization(LCRP)and investigated their stimuli-responsive properties.Aiming at convenient and efficient synthesis of block copolymer nano-assemblies,we have developed several methods based on polymerization-induced self-assembly(PISA).Herein,we give a short summary of our research in these years.The aim of this account is to stimulate innovative synthesis strategies of block copolymer nano-assemblies,and promote more scientific research cooperation to face the exciting opportunities and challenges encountered in block copolymers.
文摘Four armed star shaped copolymer of methyl methacrylate(MMA)/ N cyclohexylmaleimide(NCMI) with heat resistance was synthesized by atom transfer radical copolymerization with the CuBr/bpy catalyst in anisole, initiated by tetra(bromomethyl)benzene. A linear plot of ln( 0/) versus reaction time was obtained by using anisole as solvent. In contrast, the use of cyclohexanone as solvent results in that the rate of copolymerization decreases as the reaction proceeds. Using anisole as the solvent in the copolymerization, the molecular weight of the resultant copolymer(measured by triple detection SEC) increased linearly with the increase of conversion, and the molecular weight distributions are narrow. The glass transition temperature of the resultant copolymer was higher than that of the pure PMMA. The synthesized four armed star copolymer was used as macroinitiator for the cationic polymerization of 2 methyl 2 oxazoline to yield star shaped poly(MMA co NCMI)/poly(2 methyl 2 oxazoline) block copolymers. The approximately linear increase of the molecular weight with the increase of reaction time and the low molecular weight distribution demonstrate a controlled chain extension reaction.
