The thermal decomposition behaviors of four chemically modified polyethylene were investigated by high resolution pyrolysis gas chromatography\|mass spectrometry (HR PyGC-MS).The results revealed that substituents attached to maleated polyethylene as amides formed from secondary amines are significantly less stable than imides formed from primary amines.N-methylaniline amide-derivatives of maleated polyethylene undergo significant decomposition at 160℃ and substantial decomposition at 200℃.In contrast,the imides (except aniline imide) derivatives of maleated polyethylene are stable for long periods of time at 160℃,and the decomposition of phenethylamine imide-,9-aminomethylphenanthrene imide-derivatives is initiated slowly at 255℃ and 280℃,respectively.The effect of different modified groups on thermal stability of the polymers was discussed based on the qualitative and quantitative determination of the products.The thermal degradation pathways for the above chemically modified polyethylene were suggested.
The polyelectrolyte multilayer films were prepared by the layer-by-layer deposition of polyelectrolytes on the charged surfaces substrates. A simple process was developed to create a large area and discrete microporous thin films based on PDDA/NaPSS multilayer films by using immersing the multilayer film into pure water at an appropriate temperature and period. The microporous morphology of the multilayer film is controlled by temperature and time, and observed by atomic force microscopy. It is observed that the total area of the micropores in the films increased with immersing temperature and time. In addition, the microporous process of PEM films in hot pure water is discussed. This unique way to fabricate the microporous films has potential applications to the fields from microelectronic materials to biomaterials.
