摘要
研究了聚甲基丙烯酸甲酯(PMMA)超疏性阵列圆柱微结构特征功能表面的微热压成型技术,通过模拟研究了成型工艺参数对成型过程的影响规律,揭示了其热黏弹塑性变形充填流动机理,明晰了关键调控参数。结果表明,基片材料的弹性模量、成型温度和压力是影响充填成型的关键调控参数,成型压力和变形应力与成型温度呈负关联关系,而充填高度与成型温度呈正关联关系;提高成型温度至高于基片材料的玻璃化转变温度(Tg),使基片处于黏弹性高弹态,易使基片快速产生明显的热黏弹塑性变形,且可使成型压力和变形应力趋于最小值,这有利于基片避免断裂损伤并加速充模流动。
This paper reported a study on the patterning superhydrophobic surface with a PMMApillared array based on the micro-hot embossing technology.The effect of process parameters on the micro hot embossing process was investigated by means of numerical simulation,and the thermal viscoelastic plastic deformation filling mechanism was described. Moreover,the key control parameters were clarified.The results indicated that the elastic modulus of the base materials,hot embossing temperature and pressure are the key control parameters for the microhot formation.The hot embossing pressure and deformation stress were reciprocally correlated with the hot embossing temperature,whereas the filling height of polymers was proportionally correlated with the hot embossing temperature.With increasing hot embossing temperature over the glass transition temperature of a polymeric base material,the base material could be kept in a high elastic state.In this case,the base material is easy to perform a significant thermal viscoelastic plastic deformation in a rapid way,which can minimize the hot embossing pressure and deformation stress.This is beneficial for polymeric base materials to avoid fracture damages and promote filling flow.
引文
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