Copolymerizations of styrene (St) with 2-methyl-1-phenyl-2-propen-1-one (PIK) were carried out in the presence of stannic chloride or zinc chloride in toluene. Polymerizations occured spontaneously, giving a mixture of equimolar PIK-St copolymer and polystyrene. The copolymer was 1: 1 alternating copolymer as shown by the monomer feed-copolymer composition curve and NMR and IR spectroscopy. The results indicate the concurrent occurrence of the homopolymerization of the ternary complexes [SnCl₄·PIK₂·St_n and ZnCl₂·PIK₂·St_n (n=1 or 2)] and the cationic polymerization of St caused by partial ionic dissociation of the ternary complexes.

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Ethylene-vinyl alcohol copolymers (EVA) were formalized in solid. Infrared spectrum, density, and sorption of water were measured at various degrees of formalization and compared with those for formalized PVA. The results obtained are as follows. (1) The degree of formalization for EVA was satisfactorily determined by the ratio of optical density, D_800cm^-1/D_850cm^-1. (2) The variation of optical density of the crystalline band at 1141cm^-1 with a degree of formalization was rather small, indicating that the formalization occurred only in the amorphous region. (3) Relationship between degree of formalization and reaction time observed for PVA, did not hold for EVA. (4) Maximum degree of formalization was about 16%, which was smaller than the value estimated from the experimental evidences for PVA. (5) The molar ratio of absorbed water to OH group in the amorphous region was constant irrespective of a degree of the formalization. These results showed that the formalization occurred only in the amorphous region.

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The quantum yield (Φ) for the photoreduction of ferric chloride was remarkably increased on addition of poly (vinyl alcohol) (PVA) or isopropanol (i-PrOH). The Φvalue increased with an increase in PVA and i-PrOH concentrations and approached a constant value at their high concentrations. The smaller Φ value for PVA than that for i-PrOH Was caused by a steric hindrance for the hydrogen abstraction reaction between PVA and a ligand radical from the primary photoreaction of ferric chloride. The Φ value in the presence of PVA or i-PrOH was dependent on pH of the system due to the change of ligand of ferric cation with pH. In the acidic region where no precipitation of ferric hydroxide was observed, Φ showed a maximum value, 0.2 for i-PrOH and 0.13 for PVA, at pH 2. Dependence of the Φ value on the degree of polymerization of PVA was shown. A PVA sample after photoreaction contained unsaturated ketone groups on a polymer chain.

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The polymerization of sodium methacrylate (MAA·Na) was kinetically investigated in aqueous solution in the presence of chitosan acetate salt (CS·AcOH) using potassium persulfate (KPS) as an initiator. The polymerization rate (Rp) in the presence of CS·AcOH equimolor to MAA·Na, was expressed as follows.
R_p=k [KPS]⁰ [MAA·Na]^0.8 for [KPS] <3.5×10^-3mol/l
R_p=k [KPS]^1.8 [MAA·Na]^0.8 for [KPS] >3.5×10^-3mol/l
Molecular weight of poly (methacrylic acid) (PMAA) obtained at polymerization temperature below 60°C with the initiator of low concentration increased linearly with increasing the conversion. The polymerization proceeded with rapid initiation, succesive propagation and no termination. These results as well as analysis on the end group of PMAA indicated that an initiation occurred at reducing end-groups of chitosan, and that the propagation reaction proceeded among MAA molecules bound on chitosan molecule by the ionic and hydrophobic binding.

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The hydrostatic cold extrusion was carried out on low-density polyethylene (LDPE) with a die having die-angle of 45°, and characteristics of the extrusion, the effects of the extrusion conditions on the molecular orientation and mechanical properties of extruded LDPE were examined. Main results obtained are summerized as follows. (1) The extrusion proceeds at comparatively high rates at an initial stage, but the rate decreases gradually until the steady-state is reached. (2) An equation derived by Pugh and Low for the hydrostatic extrusion of metals can be apolied to LDPE extruded at low or high processing ratio. (3) The degree of crystallinity and size or crystallites decrease with increasing extrusion ratio, because of break down and disintegration of the fold-chain structure. (4) The crystalline orientation of extrudates is typically uniaxial one in which the c-axis orientation parallel to the extrusion axis becomes higher with increasing extrusion ratio. (5) The molecular orientation in the extrudates is uniaxial with cylindrical symmetry around the extrusion axis. (6) The tensile strength and Young's modulus of the extrudate increase monotonically with increasing extrusion ratio; and the elongation at break shows a prominent maximum at a relatively low extrusion ratio, then it decreases to a level.

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By a convenient method proposed here, flexural stress relaxations were measured for unsaturated polyester resin (UP) and fiberglass reinforced plastics (FRP) over a temperature range covering the heat distortion temperature (HDT) (71°C) of UP. The results were successfully analysed in terms of the five element Maxwell model,
σ (t) =ε₀ (E₁+E₂e^-t/λ₂+E₃e^-t/λ₃), (λ₂>λ₃). At temperatures lower or higher than HDT, the equilibrium moduli, E₁, of UP were -10¹⁰ and -10³dyn/cm², respectively. with a two order difference. While, E₁ of FRP remained in the order of 10¹⁰dyn/cm² in the same temperature range, as a result of the fiberglass reinforcement. The temperature dependence of λ₂ for UP was about three times larger than that for FRP. The dependences of λ₃ for UP and FRP were not much different. These results suggest that the first and second terms in the Maxwell model for FRP include the effects of fiberglass and filler, while the third one includes that of resin.

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