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Four types of fluorine-containing aromatic poly(ketone)s, poly(ether/ketone), poly(ketone), poly(sulfide/ketone) and poly(sulfone/ketone), were synthesized from 4,4'-[ 1 -(trifluoromethyl)trifluoroethylidene]dibenzoic acid and diaryl compounds, diphenyl ether, diphenyl ketone, diphenyl sulfide and diphenyl sulfone, by direct polycondensation using phosphorus pentoxide/ methanesulfonic acid as both condensing agent and solvent. The expected chemical structures were confirmed by IR and 'H NMR spectroscopy and elemental analysis. Two series of fluorinecontaining copoly(ketone)s, copoly(ether/ketone) and copoly(sulfide/ketone), were also similarly prepared by using different proportions of the dicarboxylic acid and the corresponding analogous 4,4'-isopropylidenedibenzoic acid but without fluorine, and the effect of the introduction of the fluorine atom on the properties of these polymers was discussed with relation to the fluorine contents. Most of the poly(ketone)s with and without fluorine were essentially amorphous and soluble in a wide range of organic solvents including chloroform and tetrahydrofuran, and afforded transparent films by solution casting. The contact angles of the films to water increased significantly and monotonously with increasing fluorine content in the copoly(ketone)s. Thermal properties such as glass transition temperature and thermal stability were also successfully improved by the introduction of a fluorine atom, and both of them increased markedly and monotonically with the increase of the fluorine content.

ABSTRACT:The tensile shear adhesive-free adhesion properties induced by electrostatic interactions between poly(acrylic acid) (PAA) and poly[2-(dimethylamino)ethyl methacrylate] (PDMAEMA) chains grafted onto polyethylene (PE) with low-density (LDPE) or high-density (HDPE) plates were studied. PAA-or PDMAEMA-grafted PE plates were immersed in a HCl or NaOH solution or water for 24 h, and their electrostatic properties were changed before they were overlapped with each other and heat-pressed. The breaking of the substrate between the two plates with waterswollen grafted layers was observed in the low range of grafted amounts in comparison with immersion in the acidic and basic solutions. The ability of the two plates with grafted polymer chains swollen in water to strongly bond with each other was a result of electrostatic interactions formed by positively charged PDMAEMA and negatively charged PAA chains. The breaking of the substrate in the case of adhesive-free adhesion between quaternized PD-MAEMA-grafted and PAA-grafted PE plates immersed in the basic solution occurred with lower grafted amounts of PAA. This came from the strong attractive force between dissociated anionic PAA chains and quaternized cationic PDMAEMA chains in the basic solution. In addition, the adhesive-free adhesion strength of HDPE plates with the same grafted polymer chains encountered the breaking of the substrate with lower grafted amounts than that of LDPE plates. It was concluded that the grafting of polymer chains onto HDPE plates with high crystallinity was considerably restricted to the outer surface regions.

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Je nach der Menge des eingesetzten Amins (II) entstehen aus dem Cytosinderivat (I) die Pyrimidine (III) oder (IV).