| 摘要 |
<p>An organosilicon crosslinked polymer or crosslinkable prepolymer comprises the hydrosilation reaction prod. of: (a) a cyclic polysiloxane of formula (I): In (I) R = a satd. (subst.) alkyl, alkoxy, aryl or aryloxy gp.; R1 = a hydrocarbon gp. with at least one non-aromatic c=C double bond that is reactive to hydrosilation; and n = 3 or 3 and 4; and (b) at least one organosilicon cpd. with at least 2 = SiH gps. comprising: (1) a cyclic polysiloxane; or (2) a tetrahedral siloxysilane. The hydrosilation reaction is carried out in the presence of a hydrosilation catalyst. Also claimed is a process for the prepn. of the above (pre)polymers by reacting (a) and (b) in the presence of a hydrosilation catalyst. Pref. R = 1-10C alkyl, R1 = a hydrocarbon gp. contg. one carbocyclic ring or a polycyclic hydrocarbon gp., pref. a polycyclic polyene comprising a cyclopentadiene oligomer, bicycloheptadiene and its Diels-Alder oligomers cyclopentadiene, norbornadiene dimer and hexahydronaphthalene, e.g. di-, tri- or tetracyclopentadiene, dimethanohexahydronaphthalene or methyldicyclopentadiene. Pref. R = methyl, R1 = dicyclopentadienyl or 5-bicyclo(2.2.1) heptenyl and (b) is a pref. cyclic polysiloxane.</p> |
