脲醛树脂石蜡微胶囊机械性能研究

STUDY OF MECHANICAL PROPERTY OF UREA-FORMALDEHYDE RESIN PARAFFIN MICROCAPSULE

用原位聚合法制备脲醛树脂石蜡微胶囊，用扫描电子显微镜、差示扫描量热仪和红外光谱仪表征了微胶囊的微观形貌、相变特性及化学组成，并用原子力显微镜研究了微胶囊的表面形貌与机械性能。结果表明：微胶囊呈球形，其表面覆盖着更小的颗粒；主相变温-5-20℃，相变潜热约为116J／g；壁材是脲醛树脂，不同粒径微胶囊囊壁的杨氏模量平均值为1．30GPa，硬度平均值为471．61MPa，二者的单次测试结果与最大压痕深度之间存在一定负相关的关系。

Urea-formaldehyde resin paraffin microcapsule was prepared by in situ polymerization method. The microcapsule morphology, phase transition characteristics and chemical composition were characterized by scanning electron microscope, differential scanning calorimetry and Fourier transform infrared spectroscopy, respectively. Single microcapsule＇ s surface morphology and mechanical properties were researched respectively by using atomic force microscope in tapping and contact mode. The results show that the prepared microcapsules are spherical particles whose surface covered smaller particles; the main phase transition temperature range is from -5 to 20℃ and the enthalpy is about 116 J/g; the microcapsule＇ s shell is composed of urea-formaldehyde resin. The testing results of AFM show that the average values of different size microcapsule＇ s young＇ s modulus and hardness are 1.30 GPa and 471.61 MPa, respectively. The test values of Young＇ s modulus and surface hardness increases with the decreasing maximum indentation depth.