STUDY ON THE CONFORMATION OF GRAFT COPOLYMER BY CONSIDERATION OF INTERACTION MEASURED BY ATOMIC FORCE MICROSCOPY

Abstract

Using the Atomic Force Microscopy, we observed adsorbed Polycarboxylate Superplasticizer（PC）on Sapphire substrate. Furthermore, we measured force curve between probe of AFM and Sapphire substrate or adsorbed PC. According to previous research, those were reported that adsorbed conformation of PC is different by degree of side chain polymerization or calcium ion concentration. In order to make clear these variation, we examined adsorbed conformation with steric hindrance model considering interaction between particles in the suspension. In existence of PC, steric repulsive force arises from extending side chain and in the liquid measurement, hydration force occur by existence of water molecule. Van der Waals force work between ions, molecules or atoms. In this paper, we evaluated with total of interactions which are steric repulsive force, hydration force and van der Waals force.
We performed a fitting of the force curve depend on adsorption layer thickness different of degree of side chain polymerization. According to this result, we couldn’t presume adsorbed conformation with steric hindrance model at the small degree of side chain polymerization. In order to review adsorbed conformation, added evaluation of adsorption layer thickness using two methods. As a result, PC adsorb with several PC cohere, but this paper is recommended that adsorbed conformation change by degree of side chain polymerization.