The thermal shock resistance of particulate-filled epoxide composites was studied based on our previously proposed test and evaluation methods. Alumina, silica and CTBN (carboxyl-terminated liquid butadiene-acrylonitrile copolymers) particles were used as fillers.
The thermal shock resistance of alumina-particulate-filled epoxide composites increased with the increase of particulate size, and decreased with the increase of filler contents in the range less than 100phr, while it held almost constant value over the content of 100phr.
The remarkable improvement of the resistance was observed for silica filled composites, even in a higher content region. Fracture surface observed with a SEM showed the difference bonding appearance at particulate/matrix interface corresponding to the different thermal shock resistance between alumina and silica filled composites.
In the case of CTBN filled epoxide composites, the improvement of the thermal shock resistance was clearly recognized.
The critical temperature difference (Δ Tc) at which the crack began to grow from the notch of the specimen was discussed theoretically based on fracture mechanics.
Theoretical and experimental results of K_I*corresponded to Δ Tc agreed well for all the filled composites. However, the effect of internal stress at the interface in highly alumina-filled composites, and the effect of craze formation at the notch tip in CTBN filled composites will also have to be considered.

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Melamine resins have been used as one of the important crosslinkers for alkyd, acrylic and epoxy resins. Generally their curing has been performed at 130-150°C for 20min, but lower temperature curable or rapid curable melamine resins have been studied extensively in recent coating industries from the view point of the reduction of energy in the curing process.
In this paper, a commercially available melamine resin was separated into five fractions by preparative gel permeation chromatograph. Chemical and molecular characteristics of the fractions were examined. Then alkyd/melamine coatings were studied by analysis of the reaction volatiles evolved during baking and measurement of physical properties of the cured film.
A key to improved curability at a rapid curable baking condition was found to be introduction of higher molecular weight fractions of the melamine resin.

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The contribution of inter- and intramolecular photocrosslinking for the formation of threedimensional network polymers was studied on polymers of 2-cinnamoyl-oxyethyl methacrylate (CEMA) with methyl methacrylate in THE solution under U. V. irradiation at 30°C. The extent of inter-and intramolecular crosslinking for the polymers was estimated by GPC and light-scattering measurements. The formation of three-dimensional network polymers during the competitive interand intramolecular crosslinking in solution depends on the amount of CEMA mol% in a polymer, the molecular weight of polymers and the initial polymer concentration. The number of intramolecular crosslinks per polymer chain increases linearly with increasing CEMA mol% in a polymer and the molecular weight of polymers. The contraction of polymer coils proceeds by predominant intramolecular crosslinking in solution, and at the onset of gelation the volume of the crosslinked polymer coil shrinks to 1/10-1/350 of the volume of corresponding linear polymer with the same molecular weight. The resulting microgel and macrogel were composed of networks having the number of intramolecular crosslinks in all cases.

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The thermal properties of new three diacetylene imides derived from 4-ethynylphthalic anhydride were investigated. These imides began to cure as soon as melting occurred. In the imide having allyl groups (A1I), allyl groups and diacetylene groups co-reacted to afford network structure with more thermal stability than two other imides having saturated alkyl groups.
On the other hand, the diacetylene groups of the imide having phenyl groups (PhI) reacted thermally over 300°C with partial decomposition because of its rigid structure.
The value of the modulus of All cured at 300°C was 7.3 GPa. However, curing at higher temperature led to partial thermal decomposition.

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An overview of modification of epoxides with reactive rubber like oligomers is described to improve poor crack-growth resistance of the commercially available epoxides. Introduction of reactive rubber like oligomers into the backbone gives the epoxide flexibility without decrease in properties such as water and chemical resistance and adhesion ability.
Urethane, butadiene-acrylonitrile and polysulfide oligomers are applied to the modification.
Particularly, it is emphasized how the modified epoxides using oligomers can be designed and prepared, and characteristics of the modified epoxides in use are also described.

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It is well known that phenolic FRP provides excellent fire-retardancy, low-smoke emission and low toxicity.
Recently, second generation phenolic resins which show low viscosity and high solid content as well as also new curing catalysts have been developed.
This enables us to mold phenolic FRP by various molding methods as molding unsaturated polyester FRP.
The up-to-dates were here reviewed on phenolic FRP, especially on new phenolic resin/catalyst systems, molding methods, properties and their applications.

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