The rigid γ-globulin matrix (50 mg) as a carrier for drug delivery system was made by γ-ray irradiation after melt-pressing at 75°C under a pressure of 100 kg/cmm2. The in vivo degradation (weight loss) of the matrix when implanted subcutaneously in the back of wistar rats was about 1.9% at 90th day from implantation. When 0.1 M Tartarate buffer solution (pH 1.8) containing 0, 0.005, 0.01 and 0.1 w/v% pepsin was used as a digestive medium (37°C), the in vitro degradation (weight loss) of the matrix was 1.2, 31.4, 45.7 and 53.9% at 90th day from start of the test, respectively. Therefore, it was concluded that the in vivo degradation of the matrix was much slower than that in vitro. On the basis of these results, testosterone (15 mg) as a drug was entrapped in γ-globulin matrix irradiated after melt-pressing. The in vivo degradation of matrix itself was significatnly accelerated in the presence of drug, and reached up to 57.4% at 90th day from implantation. The in vivo release of drug from the composites was investigated using castrated Wistar rats. Furthermore, the study of the relationship between the in vivo release of drug and the physiological response (change in wight of the ventral prostate) indicated that the efficacious drug release continued up to 60 days.

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Reaction products of 2, 2-diphenyl-1-picrylhydrazyl (DPPH) with initiating radicals in the presence of styrene monomers were investigated by field desorption mass spectrometry (FDMS). 2, 2-Azobis (isobutylonitrile) (AIBN) or azobis (2, 4-dimethyl valeronitrile) (ADVN) was used as the initiator. AIBN and ADVN were mixed with DPPH, styrene monomer, and solvents at the ratio of 5.3: 12.5: 10: 72.2 and 8: 12.5: 10: 69.5, respectively, and polymerization was carried out by heating the sample at 80°C for 1 h. Dioxane and toluene were used as the solvent for polymerization with AIBN and ADVN, respectively. FDMS spectra of the resultant products were measured, and were compared with each other, As a result, the existence of many kinds of molecular species was confirmed by examining the spectra in detail, although only a few molecular species have been clarified to be exist in the reaction system until now. For example, molecular species which were produced by the reaction DPPH with two or more initiating radicals could be found to be exist in the reaction system. By taking account of the amounts of reaction products deduced from the mass spectral peak intensities, the difference of the FDMS spectra between Figures 1 and 2, and probability of proceeding of the reactions, reaction schemes and molecular species in the reaction system were proposed as shown in Figure 3. It was concluded that the major part of the inhibition reaction of DPPH with initiating radical, could be clarified, although further investigations would be required for complete analysis of thereaction mechanism, and that FDMS was useful for analysing polymerization mechanism.

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Ethylene-vinyl alcohol copolymers (EVA) were formalized in solid form. The effects of formalization on the permeation and the diffusion of water vapor for EVA membranes were investigated. The results obtained are as follows. (1) Permeability coefficients (P) increased with increasing the degree of formalization. P greatly increased with increasing relative humidity in the range under 65% RH, but slightly in the ragne over 65% RH. (2) Diffusion coefficients (D) for formalized EVA greatly increased with increasing relative humidity in the range under 65 % RH, but decreased over 65 % RH. This result suggests that the variation of P with relative humidity is mainly dependent upon the variation of D. (3) The great increase in D with relative humidity in the range under 65% RH is dependent upon the increase in the free volume due to plasticization by water molecules. (4) The decrease in D with relative humidity in the range over 65% RH is due to the clustering of water molecules. (5) The Arrhenius plots of P were represented by two straight lines, and a bending point was seen in the temperature range of 40-50°C at 33% RH and 30-40°C at 85% RH respectively. (6) Apparent activation energies for permeation (Ep) decreased with increasing of the degree of formalization; these results corresponded with the variation of P.

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Hydrophilic gels having a void in the center of bead were prepared by suspension copolymerization of N, N-dimethlacrylamide with N, N′-methylenebisacrylamide in an aqueous solution of sodium sulfate and carboxymethyl cellulose using a diluent, which was separated from the monomer phase during suspension polymerization. Every bead had a void at the inner part and a coagulum of fine particles at the outer part, forming a skin layer at the surface of the bead in the case of above 200 wt% of diluent to monomer. The permeabilities were determined by eluting water soluble materials, such as poly (ethylene glycol) and dextran, through a column packed with the gels. Excluded critical molecular weight and degree of bulkiness increased with increasing in the amount of diluent up to about 100 wt% to monomer and then decreased above about 150 wt%. This behavior has been ascribed to the structure of gel beads described above.

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Powdered rigid polyurethane foam wastes could be reclaimed as a filler for flexible polyurethane foams by reacting them with 2-aminoethanol in polyetherpolyol, a raw material for flexible polyurethane foams. Both toluenediisocyanate (TDI) -based rigid foams and diphenylmethanediisocyanate (MDI) -based ones satisfactorily reacted with 2-aminoethanol, resulting in the introduction of hydroxyl groups. The resultant dispersion mixtures have been proved utilizable to form the flexible foams without separating the treated powders and the reaction medium.

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Viscosities of the pure liquid state of ethylene glycol oligomers HO (-CH₂CH₂O-) _nH (n=1, 2 and 3), propylene glycol oligomers HO (-CH₂CH (CH₃) O-) _nH (n=1, 2, 3 and 4), and propylene glycol diacetate oligomers CH₃COO (-CH₂CH (CH₃) O-) _nCH₃CO (n=1, 2, and 3) were measured to investigate changes of relaxational modes with variation of the degree of polymerization for the oligomers. The viscosities of the two diols are too high to be measured with an Ostwald-type capillary viscometer. A falling-body-type viscometer was made to measure high viscosity. The viscous properties of the diols were compared with their dielectric relaxational behaviors. The densities of ethylene glycol oligomers are larger than those for propylene glycol oligomers. Both the viscosities and the relaxation times of dipropylene glycol are the largest of the propylene glycol oligomers. On the other hand, the viscosities of ethylene glycol oligomers increase with increasing degree of polymerization, but as for the relaxation times of the ethylene glycol oligomers, those of diethylene glycol are the largest. The viscosities of propylene glycol diacetate increase with increasing degree of polymerization, but their values are one-tenth smaller than those of propylene glycol oligomers due to the lack of hydrogen bonds. The relaxational mechanism is discussed. The smaller viscosities of ethylene glycol oligomers are due to the regular molecular packing in the liquid structure, which facilitates molecular orientation around a molecular axis.

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Penicillium spiculisporum produces γ-lactone of 3-hydroxy-1, 3, 4-tetradecanetricarboxylic acid (spiculisporic acid) efficiently from glucose. The surface active properties and the effects of the neutralization degree of these polybasic biosoaps on emulsion polymerization of acrylic monomer were investigated. It was found that (1) fine polymer latex (below 50 nm) and the latex consisting of large size particles (above 500 nm), respectively, were produced with the mono and disodium salts of spiculisporic acid under the usual concentrations of emulsifiers, (2) the cross-linking reaction occurred in the latex particles in the case of the disodium salt and trisodium salt of spiculisporic acid as an emulsifier, and the degree of cross-linking increased with increasing amount of the emulsifier.

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For the development of novel dental adhesives, glycidyl methacrylate derivatives having substituted phenyl or fused polycyclic groups as hydrophobic groups were synthesized to study the effect of the structure on adhesiveness to tooth enamel. The monomers containing alkylphenyl groups showed higher tensile strength than those with fused polyring groups. Small alkyl groups such as methyl and ethyl groups on the aromatic ring tended to increase adhesive strength, but on standing, reduction in strength appeared to be inevitable. On the other hand, the long chain alkyl and phenyl substituents showed intermediate contribution to enhance ad-hesiveness without reduction in strength on standing.

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Hydrogen-bonding polymer complexes were obtained as precipitates in fiber forms in good yields when aqueous solutions of syndiotactic poly (methacrylic acid) (st-PMAA) and poly (ethylene oxide) (PEO) were frozen at -78°C followed by defreezing at room temperature.
The shape of fibres depended on the molecular weight of PEO used : densely coiled fibers were obtained from PEO with mol wt of 6 × 10³ and entangled long fibers from PEO with mol wt of 2 × 10⁴.

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