Epoxy resin is widely used in electronics and electric industries because of its superior properties. In recent years, excellent adhesive properties for metals (e.g.; copper, gold, aluminum, silver etc.) to which it is hard to adhere, have been desired for epoxy resin in the electric and electronics industrial fields. However, epoxy resin has only poor adhesive strength to the metals. In order to increase the adhesive strength between epoxy resin and copper foil, introduction of polymer modifiers containing sulfur, having strong interaction with metals, was investigated. TDP polyester and MPS polythioesters containing sulfur moieties were employed as the sulfur-containing modifiers for epoxy resin. Epoxy resin containing a modifier (3-10 phr) and a curing agent was cured between copper foil and aluminum plate at 120oC for 2 h and 170 oC for 2 h. The effect of the added modifiers was evaluated by the 90o peel testing method. All modifiers increased their peel strengths on the adhesion between epoxy resin and copper foil with bumpy surface. For the adhesion between the epoxy resin and copper foil with smooth surface, only two MPS polythioesters, MPS_5 and 7, have a beneficial effect on enhancement of their peel strengths.

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Ultra-low-angle microtomy has been investigated as a preparation method for the compositional analysis of thin intermediate layers in the multilayer films. In this method, target layer is sectioned by a sharp knife with keeping a low angle from the surface. The exposed face has sufficiently large area to be analyzed by TOF-SIMS, XPS or micro FT-IR. It has been demonstrated that surface freezing and staining were useful for ultra-low-angle sectioning of soft samples with Tglower than room temperature.

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Multi-component random copolypeptides consisting of N-hydroxyethyl-L-glutamine, L-glutamic acid, and L-lysine, related two component random copolymers and homopolymers, were synthesized by N-carboxyamino acid anhydride (NCA) method following deblocking of the benzyl as well as benzyloxy units of side chains by anhydrous HBr, and then aminolysis reaction with 2-amino-1-ethanol (E) of methyl unit. All the water soluble copolypeptides were found extensively degraded by random chain fracture with bromelain. Degradation data for these samples followed the Michaelis-Menten rate law, being of the first order to the enzyme concentration. It was found that the rate of enzymatic hydration for negative charged polypeptides was smaller than those for non-charged and amphoteric polypeptides.

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