In organometallic polymer chemistry, chemical analysis of the metal content of the polymers is not only a convenient approach to characterize the polymer composition1-5, but frequently it represents the only practical method of obtaining the Ml/M2 ratio in organometallic copolymers. This situation results because many organometallic monomers are difficult or impassible to analyze by g.1.c. Thus, an analysis of the unreacted monomers from the reaction mixture is tedious, and it is more efficient to analyze the resulting polymers directly. A knowledge of the mole ratio of the metal atoms in bimetallic copolymers" permits the calculation of the relative reactivity ratios', rl and r2, which define the copolymerization. In cases in which the polymer is prepared from only one organometallic monomer1-3, the knowledge of the metal content still permits the calculation of the percent of .each monomer in the copolymer. Furthermore, analysis of the metal content is often far more sensitive in indicating the Ml/M,' ratio than a carbon-hydrogen analysis would be.
When these samples are submitted to commercial analytical laboratories, the analysesare usually performed by conventional techniquesafter wet-ashing the sample. X-Ray fluorescence has already been shown to provide a rapid and in many cases a nondestructive method for the determination of the central tnetal atoms in organometallic compounds 8. A major advantage of this procedure is that more than one element may be determined on a single sample. .The technique is rapid, requiring only about 20 min for duplicates of a sample if standards are previously prepared. This technique has been applied to organometallic polymers and the results compared with those obtained by commercial analytical laboratories.