The chain length dependency of molar association constant K_a of polymer in solution was investigated theoretically. K_a is proportional to the effective hydrodynamic volume V_ eff of polymer chain in solution. V_ eff...The chain length dependency of molar association constant K_a of polymer in solution was investigated theoretically. K_a is proportional to the effective hydrodynamic volume V_ eff of polymer chain in solution. V_ eff is the product of a shape factor and hydrodynamic volume. On the basis of these results, the observed enhancement of Huggins coefficient for short chain and branched polymer could be satisfactorily interpreted.展开更多
The concentration-dependence of the reduced viscosity of dilute polymer solution is interpreted in the light of the self-association concept of polymer chain in solution. The molar selfassociation constant (Ka) is dir...The concentration-dependence of the reduced viscosity of dilute polymer solution is interpreted in the light of the self-association concept of polymer chain in solution. The molar selfassociation constant (Ka) is directly proportional to the effective hydrodynamic volume of the polymer chain in solution. In the sense of self-association or cluster formation of polymer chain in solution, there is no difference between branched and linear polymers.展开更多
A polyglycol solution containing different molecular weight PEG components waschosen as test solution. By comparing the results obtained by conventional gel permeation chro-matography GPC(water as eluent, sample solut...A polyglycol solution containing different molecular weight PEG components waschosen as test solution. By comparing the results obtained by conventional gel permeation chro-matography GPC(water as eluent, sample solution as injected solution)and Eluent-GPC (PEGsample solution as eluent, the concentrated sample solution ,diluted sample solution, water, and sample solution itself as injected solution respectively), the advantage and potential practical usage of Eluent-GPC were discussed.展开更多
Thermal evolution behavior of solution cast film of Poly(2,6 dimethyl 1,4 phenylene oxide)(PPO)/polystyrene(PS) blend was investigated by conventional and modulated differential scanning calorimetry. It was found that...Thermal evolution behavior of solution cast film of Poly(2,6 dimethyl 1,4 phenylene oxide)(PPO)/polystyrene(PS) blend was investigated by conventional and modulated differential scanning calorimetry. It was found that the original PPO/PS blend film is actually composed by a crystalline PPO phase and a non crystalline compatible PPO PS phase. The phase segregated structure state(A) will evolve to non crystalline homogenous structure(B) by subsequent thermal treatment. The effect of annealing temperature on the evolution process was discussed.展开更多
文摘The chain length dependency of molar association constant K_a of polymer in solution was investigated theoretically. K_a is proportional to the effective hydrodynamic volume V_ eff of polymer chain in solution. V_ eff is the product of a shape factor and hydrodynamic volume. On the basis of these results, the observed enhancement of Huggins coefficient for short chain and branched polymer could be satisfactorily interpreted.
文摘The concentration-dependence of the reduced viscosity of dilute polymer solution is interpreted in the light of the self-association concept of polymer chain in solution. The molar selfassociation constant (Ka) is directly proportional to the effective hydrodynamic volume of the polymer chain in solution. In the sense of self-association or cluster formation of polymer chain in solution, there is no difference between branched and linear polymers.
文摘A polyglycol solution containing different molecular weight PEG components waschosen as test solution. By comparing the results obtained by conventional gel permeation chro-matography GPC(water as eluent, sample solution as injected solution)and Eluent-GPC (PEGsample solution as eluent, the concentrated sample solution ,diluted sample solution, water, and sample solution itself as injected solution respectively), the advantage and potential practical usage of Eluent-GPC were discussed.
文摘Thermal evolution behavior of solution cast film of Poly(2,6 dimethyl 1,4 phenylene oxide)(PPO)/polystyrene(PS) blend was investigated by conventional and modulated differential scanning calorimetry. It was found that the original PPO/PS blend film is actually composed by a crystalline PPO phase and a non crystalline compatible PPO PS phase. The phase segregated structure state(A) will evolve to non crystalline homogenous structure(B) by subsequent thermal treatment. The effect of annealing temperature on the evolution process was discussed.
