Nine new kinds of thermosetting polymers with the Si(H)OC'C unit were synthesized by dehydrogenative polycondensation reactions between hydrosilanes and diethynyl compounds in the presence of a magnesia catalyst. Phenylsilane, silane, vinylsilane, and n-octylsilane were used as the hydrosilanes, and 1,3-diethynylbenzene, 1,4-diethynylbenzene, 4,4Ј-diethynyldiphenyl ether, and 1,3-diethynyl-1,1,3,3-tetramethyldisiloxane were used as the diethynyl compounds. All the polymers were thermosetting, highly heat-resistant, easily soluble in a solvent, and moldable. In particular, OSi(R)HOC'COC 6 H 4 OC'CO (R ϭ H or CHACH 2 ) showed high thermal stability; the temperature of 5% weight loss was greater than 800°C, and the residue at 1000°C was over 90%. The thermal stabilities of the polymers were attributed to the crosslinking reaction of the SiOH and C'C bonds.

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ABSTRACT:Isotherms for absorption of iodine by various polymers have been measured at 25°C in aqueous media. Poly(3-vinyl-10-methylphenothiazine) (PVMP), poly(4-vinylpyridine), and poly(tetramethylene ether glycol) absorb 3.0 g, 2.3 g, and 1.8 g of iodine, respectively, per 1.0 g of the polymer when dipped in a 0.05 M aqueous solution of 12 containing KI at 25°C. 6-Nylon, poly(vinyl alcohol), poly(acrylonitrile), poly(acrylamide) absorb 1.7 g, 1.5 g, 1.2 g, and 0.82 g of iodine, respectively, per 1.0 g of the polymer when dipped in a 0.10 M aqueous solution of 12 under the same conditions. Except for 6-nylon, the dependence of the amount of absorbed iodine on [12] K obeys a Langmuir-type equation obtained assuming the equilibrium, 12 +polymer=='" 12.-polymer complex. The equilibrium constant K ranges from 13 M-1 (for poly(vinyl alcohol)) through 53 M-1 (for PVMP). Cyclic voltammograms obtained using a polymer electrode coated on a Pt wire show the occurrence of smooth oxidation and reduction of 1-and 12 , respectively, on the surface of the polymer electrode and inside of the polymer electrode.

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Zn I Znlz I Iz‐Zellen mit C‐Elektroden, die mit Polymer‐ C‐Pulver‐Gemischen beschichtet sind, sind mit geringer Selbstentladung wieder aufladbar, wenn ein Kationen‐Austauscher?lm als Seperator benutzt wird.