A detailed investigation on the effects of catalysts on the curing of maleimide resins was conducted using model compounds. N-phenylrnaleimide (PMI) and N, N'-diphenylaspartimide (API) were selected as model compounds.
Without catalyst, PMI was polymerized at a temperature more than 200°C because of slow polymerization rate, and the product was PMI polymer (peak molecular weight by GPC=66,000). On the other hand, in the presence of API, the polymerization of PMI was accelerated a little but the product was PMI oligomer (peak molecular weight =1,000).
Imidazole catalyst (2-ethyl-4-methyl-imidazole) accelerated the polymerization of PMI at 170°C but the product was PMI oligomer (peak molecular weight=1,000) independent of the presence of API.
The catalytic effect of dicumyl peroxide (DCP) was hindered by API. Increasing of API caused lowering the polymerization rate of PMI and the molecular weight of PMI polymer.
The knowledge obtained by model reactions corresponds with the curing behaviour of maleimide resins.

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The mass-spectra of cyanoguanidine, urea, melamine, and their hydroxymethylated or methoxymethylated derivatives were measured by the in-beam ionization method.
In the mass-spectra of hydroxymethylated derivatives, the molecular ions have been scarecely observed and small peaks of dehydrated ions usually observed. The basal peaks in these mass-spectra were observed at the mass number of cyanoguanidine, urea or melamine itself, respectively.
On the other hand, the molecular ions or the protonated molecular ions were detected in the mass-spectra of alkoxymethylated derivatives. The basal peaks in these were different from those of hydroxymethylated derivatives.
The reaction products of monomethoxymethyl-and monoethoxymethyl-cyanoguanidine with a large excess of formaldehyde were determined by the mass-spectrometry and ¹H-and ¹³C-NMR spectroscopy as 4-cyanoimino-3-methoxymethyl-1, 3, 5-oxadiazine and 4-cyanoim ino-3-ethoxymethyl-1, 3, 5-oxadiazine.

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Bulk copolymerization of diallyl phthalate (DAP) with lauryl methacrylate (LMA) was explored in detail from various standpoints including rate of copolymerization, copolymerizability, gel point, gel fraction, composition of precopolymer and sol, and swelling ratio of gel. Thus the microheterogeneity in the co-curing processes was observed as a reflection of lowcopolymerizability of DAP toward LMA and great difference in the polarity of both monomers. This kind of heterogeneity was enhanced for the copolymerization of DAP with stearyl methacrylate, whereas reduced with butyl or methyl methacrylate. Furthermore, DAP was copolymerized with lauryl acrylate (LA) and vinyl laurate (VL); the extent of microheterogeneity was reduced in the order of increased copolymerizability LMA>LA>VL.

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Alicyclic epoxy/acrylic interpenetrating polymer networks (IPNs) were prepared by the UV-irradiated polymerization of 3, 4-epoxycyclohexylmethyl 3, 4-epoxycyclohexane carboxylate (Celoxide 2021) and 2-ethylhexyl acrylate (2EHA) using bis- [4- (diphenylsulfonio) phenyl] sulfide bis-hexafluoroantimonate as a photoinitiator. Celoxide 2021 dimethacrylate (crosslinker of acrylate) and Celoxide 2021 methacrylate (grafting agent) were prepared from the reaction of Celoxide 2021, methacrylic acid, and potassium methacrylate under the phase transfer conditions.
Simultaneous IPNs were opaque owing to the phase separation and grafting IPNs were transparent. Such compatibilities of IPNs were also studied by scanning electronic microscopy. The mechanical properties of IPNs were measured by tensile test. Grafting IPNs composed of epoxy/2EHA (80/20 wt ratio) were more flexible than the parent epoxy resin photocured.The thermal properties of IPNs were measured by the dynamic mechanical analysis.

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Fluorine containing polymer materials show high heat, chemical and oil resistance, oil and water repellence, lubricancy and antistickness, etc. which are not generally achieved by hydrocarbon polymers. Thus the fluoropolymer materials have been appreciably used in various fields of industry such as chemical, machinery, electrical, electronic, communication, and transportation as well as in our daily life.
This article describes the characteristic features of these fluoropolymer materials including resins, elastomers paints, membranes, oil & water repellent agents, etc. comparing with those of hydrocarbon materials. This article also deals with the ion exchange membrane for sodium chloride electrolysis and the paint resin as a specific example to explain the idea for the molecular design to complete the specific material performance.

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The excellent article of H. Staudinger and K. Wagner on “The constitution of urea-and thiourea-formaldehyde condensates” (Makromol, Chem., 12,168-235 (1954)) is studied in the present article. In chapter 1 the character of the article is described from its “introduction” and “summary”, then in chapter 3 the fundamental experiments of “Staudinger school” are introduced : i. e. the molecular weight estimation by caprolactam, methoxyl radical and chloral and the perfect elementary analysis. Meanwhile in chapter 2 the article of F. Pollak on “Methylol-thioureas (1939)” and the supplement to the article of H. Fahrenhorst (1955) are abstracted as the problems relating to the, Staudinger's article. At last in chapter 4 the melting point problems are pointed out.

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