We present here the first synthesis of cyclic oligo（ethylene adipate）s （COEAs） via pseudo-high dilution condensation reaction of adipoyl chloride with ethylene glycol, and the synthesis of corresponding poly（ethy...We present here the first synthesis of cyclic oligo（ethylene adipate）s （COEAs） via pseudo-high dilution condensation reaction of adipoyl chloride with ethylene glycol, and the synthesis of corresponding poly（ethylene adipate） （PEA） via the melt polymerization of COEAs. The structure of COEAs was characterized and proved by 1H-NMR and MALDI-TOF mass measurements. The effects of organic base, reaction temperature and the ratio of adipoyl chloride to ethylene glycol on the yield of COEAs were studied, and the optimum reaction condition was revealed. PEA, a diacid and diol based semi-crystalline green aliphatic polyester, was synthesized by the melt polymerization of COEAs using Ti（n-C4H90）4 as catalyst and 1,10-decanediol as initiator at 200 ℃, which follows the polycondensation-coupling ring- opening polymerization method. Our strategy should be applicable to the synthesis of versatile aliphatic polyesters based on diacid and diol monomers, which have potential applications as biocompatible and biodegradable materials.展开更多
Aliphatic polyesters were synthesized via the ring opening polymerization of the corresponding lactones initiated with dibutylmagnesium both in bulk and in solution. The resulting polymers were characterized by 1H, 13...Aliphatic polyesters were synthesized via the ring opening polymerization of the corresponding lactones initiated with dibutylmagnesium both in bulk and in solution. The resulting polymers were characterized by 1H, 13C NMR, GPC and XRD. The results indicated that dibutylmagnesium is an effective initiator for the ring opening polymerization of lactones.展开更多
Novel biodegradable aliphatic polyesters,poly（butylene succinate-co-triethylene glycol succinate）（P（BS-co-TEGS））and poly（butylene succinate）（PBS）,were synthesized through a two-step procedure of esterificati...Novel biodegradable aliphatic polyesters,poly（butylene succinate-co-triethylene glycol succinate）（P（BS-co-TEGS））and poly（butylene succinate）（PBS）,were synthesized through a two-step procedure of esterification and polycondensation with succinic acid and1,4-butanediol/triethylene glycol as raw materials as well as tetrabutyl titanate and diphenylphosphinic acid as the co-catalysts.The chemical structure and molecular weight of the copolymers were characterized by 1^H nuclear magnetic resonance（1^H NMR）and gel permeation chromatography（GPC）,respectively.In addition,thermal properties,crystal structure and mechanical properties were also analyzed with various techniques.P（BS-co-TEGS）exhibited more excellent mechanical properties than PBS,especially in elongation at break.Meanwhile,the crystal structure and thermal stability of the P（BS-co-TEGS）have hardly changed.The crystallinity of P（BS-co-TEGS）was lower than that of PBS and decreased with the increase of mole ratio of triethylene glycol.With the increase of TEGS unit molar composition,the melting point（Tm）,crystallization temperatures（Tc）and heat of fusion（ΔHm）of P（BS-co-TEGS）decreased,while glass transition temperature（Tg）increased.展开更多
基金the National Natural Science Foundation of China(No.21474067)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘We present here the first synthesis of cyclic oligo（ethylene adipate）s （COEAs） via pseudo-high dilution condensation reaction of adipoyl chloride with ethylene glycol, and the synthesis of corresponding poly（ethylene adipate） （PEA） via the melt polymerization of COEAs. The structure of COEAs was characterized and proved by 1H-NMR and MALDI-TOF mass measurements. The effects of organic base, reaction temperature and the ratio of adipoyl chloride to ethylene glycol on the yield of COEAs were studied, and the optimum reaction condition was revealed. PEA, a diacid and diol based semi-crystalline green aliphatic polyester, was synthesized by the melt polymerization of COEAs using Ti（n-C4H90）4 as catalyst and 1,10-decanediol as initiator at 200 ℃, which follows the polycondensation-coupling ring- opening polymerization method. Our strategy should be applicable to the synthesis of versatile aliphatic polyesters based on diacid and diol monomers, which have potential applications as biocompatible and biodegradable materials.
文摘Aliphatic polyesters were synthesized via the ring opening polymerization of the corresponding lactones initiated with dibutylmagnesium both in bulk and in solution. The resulting polymers were characterized by 1H, 13C NMR, GPC and XRD. The results indicated that dibutylmagnesium is an effective initiator for the ring opening polymerization of lactones.
基金Supported by Anhui Sealong Biotechnology Co.,Ltd(China)
文摘Novel biodegradable aliphatic polyesters,poly（butylene succinate-co-triethylene glycol succinate）（P（BS-co-TEGS））and poly（butylene succinate）（PBS）,were synthesized through a two-step procedure of esterification and polycondensation with succinic acid and1,4-butanediol/triethylene glycol as raw materials as well as tetrabutyl titanate and diphenylphosphinic acid as the co-catalysts.The chemical structure and molecular weight of the copolymers were characterized by 1^H nuclear magnetic resonance（1^H NMR）and gel permeation chromatography（GPC）,respectively.In addition,thermal properties,crystal structure and mechanical properties were also analyzed with various techniques.P（BS-co-TEGS）exhibited more excellent mechanical properties than PBS,especially in elongation at break.Meanwhile,the crystal structure and thermal stability of the P（BS-co-TEGS）have hardly changed.The crystallinity of P（BS-co-TEGS）was lower than that of PBS and decreased with the increase of mole ratio of triethylene glycol.With the increase of TEGS unit molar composition,the melting point（Tm）,crystallization temperatures（Tc）and heat of fusion（ΔHm）of P（BS-co-TEGS）decreased,while glass transition temperature（Tg）increased.
