| 摘要 |
<p>1413278 Increasing M.W. of elastomers UNIROYAL Inc 21 March 1974 [22 March 1973] 12604/74 Headings C3P and C3E The molecular weight of elastomeric diene polymers is increased by treating the polymer in fluid form (i.e. either dissolved or as a liquid polymer) and under substantially anhydrous conditions with a catalyst system comprising (1) a halogenated or halogen-free dimethylol phenol, e.g. a brominated phenol-formaldehyde resin or the halogen-free equivalent, and (2) an inorganic Lewis acid, e.g. BF 3 etherate or FeCl 3 , in amount and under conditions such that no gelation of the polymer is caused. Numerous rubbers may be treated, those in the examples being cis-1,4-polybutadiene, natural rubber, SBR and EPDM.</p> |
