摘要 |
Dry, powdered, crystalline polymers of a -olefines containing 3 to 7 carbon atoms are oxidized with a gaseous oxygenating agent at a temperature below the melting point of the polymer. The polymer may be a homopolymer of propylene, 4-methyl-1-pentene, 3-methyl-1-butene or 3-methyl-1-hexene. The temperature of oxygenation is between 90 and 145 degrees for polypropylene and between 90 and 180 degrees for the other poly-olefines. The oxygenating agent may be air or oxygen and may be diluted with nitrogen or other inert diluent. The dry polymer powder may be obtained directly from the polymerization reactor, otherwise it may be made by precipitation from a polymer solution using a non-solvent. The time of heating varies from one quarter to thirty hours. Heating may be carried out using a heat lamp or an ultra-violet lamp. The product is a readily emulsifiable, dyeable and printable crystalline polymer. Specifications 952,431 and 952,432 are referred to. |