Acetylene-containing polymers, obtained by the radical polymerization of aliphatic enynes, were subjected to the thermal crosslinking reaction on the basis of the reactivity of the acetylene moieties. Thermal properties of the resulting crosslinked polymers were dependent upon the character of the substituents, being also correlated to the thermal decomposition temperatures of polyenynes. Namely, the polymers having sterically less hindered substituents have higher decomposition temperature than those having hindered substituents as a result of efficient crosslinking process.

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The volume expansion of poly (N,N-dimethyl-4-vinylphenylamine) based on photo-induced electron transfer was examined. The polymer film was irradiated with a 400W high pressure Hg lamp in methanol in the presence of CCl₄ at 30°C for 5h. It showed volume expansion as large as 15,600%. The copolymer with styrene was also synthesized to measure the photo-induced volume expansion. The copolymer with a more N,N-dimethyl-4-vinylphenylamine unit showed a larger volume expansion.

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The corrosion behavior was investigated on an alumina filled bisphenol A type epoxy resin. Specimens were immersed in an alkaline solution for examining the effects of alumina content and particle size on the corrosion behavior. While the neat resin did not show any significant change in the retention of flexural strength, the alumina filled resin obviously decreased the retention. The corrosion depth linearly increased with immersion time. The corrosion rate, defined as the slope of the corrosion depth per unit time of immersion, was strongly affected by the volume fraction of alumina contained; on the other hand, was a little affected by the effect of average particle size. The cause of the increase in corrosion rate with alumina content was clarified by a microscopic investigation as follows : the alkaline solution penetrating into the specimen corroded it through passing along the surface of particles. The chemical degradation model was proposed in order to obtain the corrosion rate for an arbitrary alumina content of a composite.

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The late Dr. Yanagida believed the ammonia-catalyzed phenol-formaldehyde reaction to be first order, while the acid-catalysed reaction to be second. The present author made his opinion clear, collecting the activation energy of these reactions. About the NaOH-catalyzed reaction he found that both orders coexisted, each activation energy being 16 and 23 Kcal/mol., after re-examining the paper of Dr.L.M.Yaddanapalli and V.V.Gapalakrishna.

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This paper covers some significant issues in Market Development with the Network Polymer Composites in Europe. The keen interest in these issues is also occupied by Americans. Indeed, seemingly, Americans have been historically and independently developing their market by themselves. However, they have much been influenced through getting suggestions from Europeans.
The feature in market development in Europe must be, first of all, creativeness. Many useful tools of today's science and technologies have been produced in Europe and even nowadays. Europeans play a role of leading activities in building new technologies. In case of this Market Development with Network Polymer Composites, it could be found that a similar tendency is much concerned by the world including us in Japan.

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The trend in electronic equipment is toward greater compactness of design, lighter weight, and higher speed and digitization to provide enhanced functions. The semiconductors and printed wiring boards that make up such electronic equipment are therefore required to feature ever-higher speed and densities.
ALIVH (Any Layer IVH Structure Multi-layer Printed Wiring Board) has an IVH structure in every interlayer. As a result, it has greater potential for downsizing than conventional types, and is ideal for highspeed applications due to being able to shorten its wiring. Furthermore, easier designing due to having no through-holes is one of its outstanding feature, compared with other types.
Since the first introduction of its revolutionary ALIVH technology in 1996, we once again have successfully launched ALIVH-B into commercial use in 1998 for bare chip mounting. The chief focus has recently been turned to ALIVH-B as a substrate for bare chip mounting, owing to its high mounting reliabil-ity and high compatibility for high-speed applications.
In this paper, several technical aspects of new organic high density substrate ALIVH and ALIVH-B including products' profiles, processes, applications, reliability, future evaluation trend, and tasks to be solved, will be discussed.

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