| 2 | HYDRATION AND PHASE SEPARATION OF TEMPERATURE-SENSITIVE WATER-SOLUBLE POLYMERS显示文摘倒塌一( N-isopropylacrylamide )( PNIPAM ) poly 在加热之上锁住并且与很扁平的 LCST 分阶段执行水的 PNIPAM 答案的图阶段分离线理论上根据合作脱水(在一组相关顺序的界限水分子的同时的分离)被学习,并且与由光的导致温度的卷水珠转变的试验性的观察相比散布方法。转变与水和的 cooperativity 参数变得更锋利。在水和甲醇的混合溶剂的重入的 coil-globule-coil 转变也从在聚合物水和聚合物甲醇之间的竞争的氢契约的观点被学习。向下,有甲醇的鼹鼠部分的云点曲线(LCST cononsolvency ) 的移动由于比赛被计算并且与试验性的数据相比。在两链结束(telechelic PNIPAM ) 带短烷基链的修改 hydophobically 的 PNIPAM 的水的答案理论上并且试验性地被学习。这些答案的 LCST 被发现由于结束链协会(导致协会的阶段分离) 沿着大音阶的第五音胶化转变曲线向下变,并且与卷水珠转变线分开。在答案的联系结构例如花微粒, mesoglobules 和更高分数维的汇编,被 USANS 与散布功能的理论建模学习。 | Fumihiko Tanaka Tsuyoshi Koga Hiroyuki Kojima Francoise M.Winnik | 2011 | Chinese Journal of Polymer Science2011，29，1： | 2 |
| 6 | New insights into the effects of molecular weight and end group on the temperature-induced phase transition of poly(N-isopropylacrylamide) in water显示文摘In an attempt to clarify issues related to the molecular weight dependence of the phase transition of poly(N-isopropylacrylamide) (PNIPAM) in water,we prepared a library of PNIPAM samples of well-controlled molecular weight (7000 to 45000 g/mol) bearing identical groups on each chain end.The polymers were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization of N-isopropylacrylamide (NIPAM) with a bifunctional chain tranfer agent and further end group modification.The effects of the end group chemical structure,hydroxyethyl (HE),propargyl (Pr),chloroethyl (CE),n-butyl (nBu),n-hexyl (nHe),and isobutylsulfanylthiosulfanyl (IBS) on the phase transition temperature of aqueous PNIPAM solutions were investigated by high-sensitivity differential scanning calorimetry (HS-DSC),yielding the enthalpy ΔH and the endotherm maximum temperature (T M),and turbidimetry,providing the cloud point (T CP) of each solution.The T CP and T M of the PNIPAM sample of lowest molar mass (M n 7,000 g/mol,0.5 g/L) ranged,respectively,from 38.8 to 22.5 °C and 42.2 to 26.0 °C,depending on the structure of the end-group,whereas H showed no strong end-group dependence.The phase transition of all polymers,except,-di(n-butyl-PNIPAM),exhibited a marked dependence on the polymer molar mass. | QIU XingPing KOGA Tsuyoshi TANAKA Fumihiko WINNIK Fran oiseM. | 2013 | Science China Chemistry2013，56，1： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员