Structural Analysis for Interface of Particle-Filled Compositeand Pressure-Sensitive Adhesive Using Pulse NMR

Abstract

Some results of structural analyses for interfacial phase of particle-filled composite and pressure-sensitiveadhesive（ PSA） using the 1H pulse nuclear magnetic resonance（ pulse NMR） measurement were reviewed.The influence of loading method of silane coupling agent on the mechanical properties of silica-filled rubbercomposite were investigated. It was higher in the integral blend method than in the pre-treatment method. Thereason was clarified by the relaxation spectrum for the unvulcanized silica/rubber mixture. The crosslinkedpoly（ n-butyl methacrylate） particles were dispersed in poly（ vinyl chloride）. This pair is completely miscible,whereas mutual diffusion of both polymers is restricted within the interfacial phase by the crosslinking points.The interfacial thickness was estimated using the pulse NMR. Tackifier exists as both dissolved moleculeand agglomerated particle in PSA. The relative ratio of agglomerated particle is able to estimate using thedifference spectrum of pulse NMR. From the comparison of difference spectra for vulcanized rubber andcrosslinked polyacrylic PSA, the restriction of molecular mobility by the intermolecular interaction was foundto be far larger in PSA than in the vulcanized rubber.