掩膜诱导的光敏性三组分聚合物混合体系的自组装

采用含时金兹堡-朗道理论(time-dependent Ginzburg-Landau theory)研究了二维体系中光敏性三组分聚合物混合体系在掩膜诱导下的相行为.详细探讨了光化学反应速率、聚合物组分比和掩膜长宽比对相分离行为的影响.获得了不同条件下体系形貌结构的相图,通过对这些相图的分析得到了岛状、网络状、层状等有序结构形成的条件.研究表明,固定掩膜的长宽比(L:d=6:4),当C组分的浓度?C0.35和光化学反应速率Γ1×10~(-5)时,体系形成岛状结构;当?C0.4和Γ1×10~(-5)时,体系主要形成层状和网状结构.固定光化学反应速率(Γ=1×10~(-3)),当6:5≤L:d≤6:1和?C0.35时,体系形成岛状结构;当6:6≤L:d≤6:1和?C0.4时,体系主要形成层状和网状结构.固定C组分的浓度(?C=0.45),当Γ≥5×10~(-4)和6:6≤L:d≤6:1时,体系主要形成层状和网状结构.稳定性分析表明这些有序结构在去掉掩膜之后仍能稳定存在.

Self-assembly of Photosensitive Ternary Blend Directed by Mask

The phase behavior of a ternary blend with photochemical reaction induced by a mask are investigated via the Time-Dependent Ginzburg-Landau theory.The effects of the composition ratio,the length-width ratio of the photomask,and thephotoreaction rate coefficient on the domain structure and formation are systematically investigated.Through analysis of the phase diagram,the conditions for the formation of the ordered structures,such as island-like,network-like,and lamellar structures,are obtained.When the photoreaction rate coefficient Γ is not larger than 1 × 10-5,the system forms a disordered structure,regardless of the strong variations in the C component concentration and the length-width ratio of the photomask.Firstly,when the length-width ratio of the photomask is fixed (L∶d =6∶4),with increasing the photochemical reaction rate,the disordered morphology transforms to island-like structure when φC ＜ 0.35;it forms disordered structure again when 0.35 ≤ φC ≤ 0.4;a transition of disordered strcture-lamellar strcture-network structure occurs in the system when φC ＞ 0.4.Secondly,when the photoreaction rate coefficient is fixed (Γ =1 × 10-3),with increasing C component concentration,the system shows a multiple morphology transition of island-like-disordered-lamellar-network when 6∶4 ≤ L∶d ≤ 6∶1;when 6∶6 ≤ L∶d ＜ 6∶4,the island-like structure changes to disordered and then to network structure.Finally,when the C component concentration is fixed (φC =0.45),with the decrease in the length-width ratio of the photomask,the morphology transforms from disordered to lamellar,and then to network when 1 × 10-5 ＜ Γ ＜ 5 × 10-4;when 5 × 10-4≤ Γ＜ 1 × 10-2,the lamellar structure turns to network structure;and when Γ≥ 1 × 10-2,the photochemical reaction rate is so fast that the A/B blend does not undergo the phase separation,and the macro-morphology transforms from lamellar to network.In addition,to gain insight into the stability of the structures obtained,a linear stability analysis is also carried out.The results show that these ordered structures can still be stable after the removal of the mask.