Free induction decay (FID) signals of　macroscopic magnetization M(t) obtained by pulsed NMR have much information on the physical properties of polymeric materials. In our previous studies,the magnetic relaxation spectra of the polymeric materials were determined by the numerical differentiation on the FID signals. In this paper,combined FID signals were calculated using the proton ratio in the SIS/SI/tackifier pressure-sensitive-adhesives (PSAs), based on the FID signal of the each component in the PSAs. The difference between the combined relaxation spectrum calculated from the combined FID signal and the measured relaxation spectrum of the actual PSAs gave the difference spectrum. The difference spectra quantified the interaction among components,such as the effect of the amount of the SI diblock and the tackifiers on the relaxation behaviors. The magnetic relaxation spectrum describes the relaxation behaviors of the protons,i.e., the mobility of the main chain and the side chain of polymers. Therefore,the difference spectrum of SIS/SI/tackifier system suggests the miscibility of the tackifier to the polyisoprene (PI) phase in the SIS/SI. The difference spectra given by the pulsed NMR are an effective method to lead the design of elastomer/tackifier PSAs.

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Gel particles with projections, which have been prepared by dispersion polymerizations of ethylene glycol dimethacrylate,macro-azo initiator and co-monomer in water/ethanol solutions, were utilized to prepare nano-filters. Nano filters were prepared by simple process; casting a dispersion mixture of the gel particles and binder polyurethane on a commercial membrane filter, followed by drying Evaluations of the nano-filters were examined by vacuum filtration using a colloidal solution of Au nano particles. Nearly 100% of Au nano particles were filtered with the prepared nano-filter in a several minutes.

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