Polypropylene(PP)/elastomer/fine filler particles ternary composites were prepared using polystylene-block - poly (ethylene-butene)-block-polystylenetriblock copolymer (SEBS) or carboxylated SEBS(C-SEBS) as elastomer and calcium carbonate (CaCO3) having mean size about 160nm asfiller.Firstly, SEBS (or C-SEBS) and CaCO3 particles were mixed to form master batch.Secondly, the prepared master batch and matrix PP were kneaded.In the PP/SEBS/CaCO3 ternary composites,CaCO3 particles and SEBS particles were dispersed in the PP matrix in dependently.In the PP/C-SEBS/CaCO3 ternary composites, CaCO3 particles were encapsulated in C-SEBS and formed a core-shell structure at the lower CaCO3concentration.However, some CaCO3 particles were dispersed inPP matrix independentlyat the higher CaCO3 concentration, and the CaCO3 particles in PP matrixincreased with the CaCO3 concentration.In the PP/SEBS/CaCO3 composites, the impact strengthincreased with the amount of incorporated CaCO3 particles.In the PP/C-SEBS/CaCO3 composites,whereas the impact strength increased dependent upon the amount of CaCO3 particles dispersed in PP matrix.The master batch method was found to be useful for improving the dispersibility of CaCO3particles than the commonly used one batch method.

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Energy absorbability of bi-layer laminates consisting of pressure sensitive adhesive (PSA) layer/cured epoxy layer was studied.The base polymers for the PSAs were acryl block copolymers andseveral types of tackifiers were blended to the base polymers.The energy absorbability (the load-displacement hysteresis loops)of the laminates was examined during impact/rebound process using aninstrumented pendulum impactor.Rosin ester and terpene phenol as tackifiers were miscible with thebase polymer, and the energy absorbability of the bi-layer laminates increased within a particularrange of the tackifier content in PSAs.The maximum energy absorption was achieved at 20wt%addition in case of terpene phenol, at 30wt% addition in case of rosin ester.Whereas, the addition ofpetroleum resin which was not miscible with the base polymer did not improve in the energy absorbability of the laminates.A RUK equation, which is originally for calculating the loss factors (η) of a non-constrained type damping steel with a viscoelastic resin layer on the surface, was applied toexplain the energy absorbability of the bi-layer laminates.The polymer composition dependence ofthe calculated ηusing the viscoelasticity of the PSAs at a particular frequency showed good agreement with that of the actual energy absorbabilityof the laminates.

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A-B-A type tri-block copolymer consisting of N-bydroxypropyl-L-glutamine as the A componentand L-leucine as the B component as well as the corresponding random copolymers and homopolymerswere prepared by carrying out an aminoalcoholysis reaction with 3-amino-1-propanol, together witha crosslinking reaction with 1,8-octamethylenediamine on membrane of the starting polymer membranes including γ-methyl-L-glutamate　residu.It was shown that the effective crosslink density was proportional to the percent crosslinker in the reaction mixture. The relation between their bulkstructure and membrane properties was investigated, such as the swelling ratio in water (q), tensileproperties, and enzymatic degradation behavior of the membranes in a pseudo-extracellular fluid(PECF).The tensile properties of the hydrophilic membranes were highly dependent on q in PECF,and on the hydrophobic portions in molecular chains, whose behavior was typical of an elastomer.Enzymatic hydrolysis of the membranes in vitro by bromelain indicated that the degradation took place in bulk rather than on the surface, and that the rate of degradation was also highly dependent on q in the samples as well as on the hydrophobic portion of the membranes in PECF.

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