Phase separation and fractionation experiments were carried out for o-cresol resin (o-CR) -acetone-cyclohexane, acetylated o-CR (Ac-o-CR) -acetone-cyclohexane, poly (p-hydroxystyrene) (PHS) -acetone-cyclohexane and acetylated PHS (Ac-PHS) -acetone-cyclohexane systems and the fractionation efficiency of the first fraction was discussed. The partition coefficient σ was adopted as a fractionation efficiency parameter. It was confirmed that the efficiency increased more as σ was greater. The fractionation efficiency was affected by the initial polymer concentration and the amount of polymer partitioned in polymer-rich phase. By comparison of σ values for o-CR and Ac-o-CR systems, or PHS and Ac-PHS systems, it became apparent that the fractionation efficiency was influenced significantly by the hydrogen bonds among the phenolic hydroxyl groups. It was suggested that the fractionation efficiency was closely related to the molecular conformation as well as to the viscosity measured in solutions.

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Effects of ceramic particles on thermal shock behavior of particulate-filled epoxy resins have been studied. Ceramic particles filled were silicon nitride, silicon carbide, aluminum nitride, aluminum hydroxide and others. Test results were evaluated from fracture mechanics and also fractographic point of view.
Resins filled with hard particles, such as silicon nitride and silicon carbide, showed high thermal shock resistance, while a resin with aluminum nitride filled to enhance thermal conductivity, did not achieve high resistance, and resins filled with aluminum hydroxide particles which were easy to break, showed lower resistance than the neat resin.
If the thermal shocked specimens showed morphologically different fracture surface from fracture toughness tests, the calculated nondimensional stress intensity factor was not in agreement with experimental critical condition. In order to evaluate the thermal shock resistance of particulate-filled resins, therefore, it is necessary that both thermal shock and fracture toughness test specimens show the same fracture surface morphology, which means the same mechanism of crack propagation.

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Three kinds of HPMI/n-BuA (monomer ratio≅1/4) copolymers which had different average molecular weights were synthesized. It was found that these copolymers had lower Tg and higher thermal decomposition temperatures than those of novolac. Molding compounds were prepared by hot roll-kneading from a novolac, the copolymer, hexamine, and glass fiber. Test pieces of modified phenolic resins were prepared by transfer molding from the molding compounds. Thermal and mechanical properties of the modified phenolic resins were examined by dynamic thermomechanometry, the test of flexural strength, and impact strength. Fracture toughness was examined using test piece without containing glass fiber.
It was found that phenolic resins modified with the copolymers had heat resistance and better impact strength than an unmodified phenolic resin, though the flexural strength of the modified phenolic resin was a little inferior to that of unmodified phenolic resin. There was no effect of average molecular weight of the copolymer upon these properties. But fracture toughness of the modified phenolic resin was inceased with the increase of an average molecular weight of HPMI/n-BuA copolymer and with the decrease of distribution range in their molecular weights. When content of the copolymer was 10phr, those showed the maximum value which was about 1.5 times as much as that of the unmodified phenolic resin. By observation with scanning electron microscope, many domains consisting of the copolymer were observed over the fracture surface. On these domains, size was smallest, distribution was narrowest, and density was highest, when content of the copolymer was 10phr.

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Many of today's electronic and electric components are compacter, lighter and more efficient, then their predecessors due to higher integration, larger capacity and high mounting density of semiconductor devices. Chip sizes and pin counts of semiconductor devices have respectively become much larger and higher, also. But to increase mounting densities, package sizes have become smaller and thinner, and package configurations have been changed from pin insertion types to surface mounting types. This manufacturing changes require epoxy molding compounds to : (1) lower the thermal expansion coefficient, thus reducing thermal stress in the package; (2) lower the moisture absorption; and (3) increase the adhesion strength, thus improving the package crack resistance at reflow soldering. This paper reviews recent technological trends and future investigation topics for epoxy molding compounds.

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In Japan trowel-grade room temperature curable urethane elastomer has commonly been used for floor covering and roofing membrane.
In recent years, a machine-applied, instant setting system was developed for such applications in the market. The reason why that system has been requested in the market are :
1) the lack of skillful workman → machine-applied system
2) short construction period → fast cure system
Those systems, consisting two-component low viscosity urethane-urea resin and aromatic diamine as a curing agent, was described, which was applied by high-pressure metering machine with a impingement-mixier and airless gun. Tack-free time and cure time were 10 to 20 seconds and several minutes, respectively. Within 30 minutes the practical physical properities appeared.
Advantages of those cure systems are :
1) 100% solids-no-solvents,
2) water insensitivity, and
3) excellent physical properities.
Due to quick reaction and lack of solvent, we can get any thickness at the same time even though they are applied to a vertical and ceiling surface, without necessity to worry about weather conditions.
Actual applications, for example, are Dome-roof at an atomic power plant, floor in an amusement park and corridor in an apartment house, pool (waterproof membrane), landslide.
This review shows the points and merits of those systems (including machines).

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Acrylic resins which show excellent appearance, weatherability, chemical resistance, etc. are widely used in the field of coating industry.
For thermosetting coatings, amino resins and polyisocyanates have been used as a conventional curing agent. Instead of them, new crossliking systems have been developed recently with some reasons.
This article briefly reviews the chemistry behind the alternative systems which can be used at ambient or elevated temparature.

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