线性梯度高分子与纳米颗粒共混体系相分离的模拟研究

Simulation study of phase separation in linear gradient copolymer/nanoparticle composites.

采用蒙特卡罗(Monte Carlo)结合退火技术研究了线性梯度高分子与纳米颗粒共混体系的相分离行为.模拟研究发现其相分离不但与梯度高分子的分布函数f(t)有关,还与链长、相互作用能和纳米颗粒浓度相关.随着参量的改变发现了无序相与层状相(L)或穿孔层状相(P)以及无序相与球状相(S)相变,此外,当在特定的单体A浓度时同时还出现了共混相,同时纳米颗粒随机分布在单体A区域内.

The structural characteristics of linear gradient AB copolymers/ nanoparticles mixtures are investigated by the simulated annealing technique and Monte Carlo method.The simulation results illustrated that the microphase-separated linear gradient AB copolymers depend on the distribution functions f（t）,the copolymer lengths,the constant interactions and the average contact numbers of the particals.Phase-transitions among disorder,lamellae（L）,perforated lamellar（P）,spheres（S） are observed.In addition,composites containing different volume fractions of A monomers exhibit two-phase coexistence between different copolymer phases.Finally,it is also found that the nanoparticles preferentially located at the preferred lamellar domain for all of the simulatings.