A series of fluorine‐containing homopolycarbonate and copolycarbonates with a wide range of unit ratio were synthesized by the two‐phase phase‐transfer‐catalyzed plycondensation of 2,2‐bis (4‐hydroxyphenyl)‐1,1,1,3,3,3‐hexafluoropropane (Bisphenol AF) and/or 2,2‐bis (4‐hydroxy‐phenyl) propane (Bisphenol A) with trichloromethyl chloroformate, and the effect of the fluorine substitution on the synthesis and properties of these polymers was investigated by comparing with those of Bishphenol A‐based homopolycarbonate without fluorine. Film‐forming moderate‐to high‐molecular‐weight fluorine‐containing polycarbonates with reduced viscosities up to 0.54 dL/g were obtained in high yields by using tetra‐n‐butylammonium bromide as a catalyst, sodium hydroxide as a base, and 1,2‐dichloroethane as a medium. The reduced viscosity, however, decreased markedly with increasing feed ratio of Bisphenol AF. Their solubility in common organic solvents was clearly improved by the introduction of fluorine atom. The pliability of the films also increased remarkably with increasing fluorine content. The contact angles formed by water were larger than 90°, regardless of their fluorine contents, at 25°C in air. The critical surface tension and refractive index of Bisphenol AF‐based homopolycarbonate were ca. 20 dyn/cm and 1.426, respectively. The glass transition temperatures and thermal stability increased monotonously with increasing fluorine content.
The mutagenicity of bovine lactoferrin, which is an iron-binding glycoprotein in milk, was evaluated by the Ames mutagenicity test. A total of 5 test strains including 3 base-pair substitution-type strains, Salmonella typhimurium TA100, TA1535 and Escherichia coli WP2uvrA, and 2 frameshift-type strains, TA98 and TA1537, were used in the test. The test was performed by both the direct method and the metabolic activation method with preincubation applied in each instance. The concentration range of the test solution was 0.16 to 5.00 mg/100 microliters (plate). Results of the test revealed that the number of revertant colonies at each concentration of the test solutions was less than 1.4 times that of the control group. In the test system used, bovine lactoferrin did not exhibit mutagenicity.
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