The Study Of Low Temperature Photo-Polymerization

There are various kinds of crystals in the nature. The crystals also exist in the polymers. It is well known that the crystal structure has a significant effect on different sorts of properties of the polymer, such as the mechanical property, the thermal property and other properties. But, the regularity and the symmetry of the polymer chain are required strictly in forming polymer crystal. Therefore, it is difficult to form polymer crystal. Based on the foundation of the kinetics study of photo-polymerization system at low temperature of pre-researchers, this paper aims at studying the micro-morphology of photo-polymerization system of acrylate at low temperature, namely, producing polymer crystal through the irradiation of Ultra-violet at low temperature. The scanning electron microscope (SEM) and the high resolution transmission electron microscope (HRTEM) are used to represent the experimental results. There are mainly two directions to produce polymer crystal:(1) HDDA photo-polymerization system is polymerized at low temperature;(2) HDDA co-polymerization system is polymerized at low temperature. Furthermore, the fracture morphology and surface morphology of the polymer obtained from HDDA system cured at low temperature are investigated. The experimental results show that the system of HDDA which is cured at-20℃,-40℃and-70℃respectively all form the flake-like crystal structure on the surfaces. Moreover, the HDDA polymerization system and the HDDA co-polymerization system which are cured at different low temperatures become polymer single crystal and polymer poly crystal respectively and the crystal size are more than1μm2. But the internal structure of the polymer obtained from the two system which are cured at room temperature is amorphous, not forming crystal structure.