Waste of polyurethane foam (PU) was utilized as a modifier to improve the toughness of phenolic resin. Novolac modified with PU was synthesized from phenol which dissolved various amount of PU and formalin under acid condition. Tg, average molecular weight, and melt viscosity of novolac modified with PU were increased with increasing PU. Molding compounds were prepared by hot roll-kneading from the modified novolac, hexamine, and wood flour. 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 deflection temperature under load and flexural properties. Fracture toughness was also examined using test pieces without containing wood flour. Heat resistance of the modified phenolic resin showed the maximum value at PU content of 10 phr. Flexural strength was improved with increasing PU, though flexural modulus was almost unchanged. Also the ultimate flexural strain value was improved. Fracture toghness of the modified phenolic resin showed 1.5 times as much as that of unmodified one at PU content of 10 phr. The mechanism of toughning for the modified resin system was investigated by dynamic thermomechanometry and scanning electron microscope. As a result, it is considered that toughning occurs based upon stress relaxation by plastic deformation in the vicinity of crack tips in a homogeneous and miscible structure.

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The filler effect of gelled polyurethane fine particles for coating film was studied in comparison with gelled acrylic fine particles and glass balloons. The film containing gelled polyurethane fine particles (the former film) showed more excellent stress-strain properties than gelled acrylic fine particles (the latter film) and also glass balloons. When two component aliphatic polyurethane resin was used as binder, it was found that the relative modulus of the former film was applicable to Sato's equation for the modulus of the composites of polymers and spherical fillers. Although latter film was applicable to Eilers's equation, rather than Sato's equation. The filler effect of glass balloons was similar to that on the latter film and the resulting coating film was fragile.
Moreover, the effect of binder, such as two component aliphatic polyurethane resin, polyurethane dispersion and acrylic lacquer on the stress-strain properties of coating film containing the fine particles was investigated.

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The bulk and solution reactions between N-Phenylmaleimide (PMI) and Aniline (AN) were carried out as a model reaction for the synthesis of amine-modified maleimide resin. In the bulk system, N, N'-diphenylaspartimide (API) is produced by Michael addition reaction between PMI and AN at a lower temperature (100°C). By-product such as fumardianilide is obtained at a higher temperature more than 100°C. N-pheny-aspartdianilide is supposed to be obtained at a higher temperature or by increasing AN content.
In N, N-dimethylformamide which is an aprotic solvent, both API and PMI oligomers are obtained. In a protic solvent such as acetic acid (AcOH), m-cresol (m-CR) or methylcellosolve (MCS), only API is obtained. The reaction rate becomes faster (AcOH>m-CR>MCS) by lowering PKa of solvent.

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The reactions between N-Phenylmaleimide (PMI) and allyl compounds were carried out as a model reaction for the resinification of allyl-modified maleimide resin. In the system of PMI/allylbenzene (ABz) or allylanisole (AA), which doesn't have phenolic hydroxyl group, reaction rates were very fast and high molecular weight copolymers were obtained. In the system of PMI/allylphenol (AP) or eugenol (Eu), which has phenolic hydroxyl group, reaction was moderate and mainly gave low molecular weight adducts (PMI/AP, Eu=1 : 1, 3 : 1). In the system of bismaleimide/diallyl compound, corresponding to PMI/AP, Eu systems, the resinification reaction was moderate and gave a solid resin melting point of which was suitable for following processing.

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This review describes organic-inorganic polymer hybrids at molecular level. The sol-gel reaction of tetraalkoxysilane was carried out in the presence of organic polymers such as poly (2-methyl-2-oxazoline) and poly (N-vinylpyrrolidone). Transparent and homogeneous glassy materials were obtained in a wide range of the composition of organic polymers. In these polymer hybrids, hydrogen bonding between amide groups of organic polymer and silanol groups of silica gel plays an important role, which is supported by FT-IR spectra. Pyrolysis of these polymer hybrids at 600°C gave porous silica having controlled pore size. A wide variety of applications can be expected by using these molecular hybrids.

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This article describes various types of star-shaped polymers that are prepared by living cationic polymerization in three ways : (A) linking reactions of living polymers with divinyl compounds ; (B) living polymerization with a multifunctional initiator ; and (C) quenching of living polymers with a multifunctional coupling agent. The three methods also led to star-shaped polymers with polar functional groups such as hydroxyl and carboxyl, including amphiphilic, water-soluble, or end-functionalized star polymers. The star-shaped polymers differ in properties such as solubility and host-guest interaction from the corresponding linear polymers.

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