The Analysis on Mechanical and Thermal Property of Poly(Acrylic Acid)-Graft-Polypropylene Membrane Prepared by UV-Irradiation

A series of pH-sensitive poly (acrylic acid)-graft-polypropylene microfiltration membranes were prepared by UV-irradiation. It was observed that the hydrophility and water permeability of grafted membranes was improved. After modification, the elongation of grafted membranes decreased significantly with the rise of grafting degree, and the glass transition temperature (Tg) of grafted membranes decreases as well. As a result, the grafted membranes have a great loss on its flexibility and become brittle. The grafting reaction weakens the thermal stability of grafted membranes. Both of the initial and the maximum decomposition temperature of 20% grafted membrane are 10 degrees C lower than that of PP matrix. But grafted membranes still show good thermal resistance till 400 degrees C. The result shows that the surface modification not only has great impact on water permeability of membranes but also affect their mechanical and thermal properties.