| 摘要 |
1,134,465. Plant growth media. AMERICAN CAN CO. Aug. 15, 1967 [Aug. 16, 1966; June 26, 1967], No.37387/67. Heading C3G. A plant growth medium comprises a felted mat of natural cellulose fibres having chemically bonded thereon a polymer formed by in situ polymerization between 50 and 500 parts of an olefinically unsaturated monomer per 100 parts of the fibres. Another bonding agent, such as water-insoluble fibres, may be present in 0.5% to 5.0% by weight of the solids, and this agent preferably comprises natural cellulose fibres having chemically bonded thereon metal salts of polyacrylic acid and formed by the polymerization of acrylonitrile, followed by hydrolysis in an alkaline medium. The medium may have a bulk density of 0.05 to 0.15 gm. per c. c. with a polymer-to-fibre weight ratio of between 0.5 to 1 and 5.0 to 1. The medium is produced by mixing the fibres, the monomer, preferably acrylonitrile, and a redox catalyst, in an aqueous medium; heating to polymerize and chemically bond to the fibres the monomer; removing the polymer modified fibres from an aqueous slurry; moulding these wet fibres into a predetermined shape and drying to rigidify this shape. The water-insoluble fibrous binder may be added to the aqueous slurry prior to the withdrawal step, and an additional step of applying a plant nutrient composition to the moulded shape, may also be included in the process. The withdrawn fibres may be moulded into a plurality of blocks spaced from each other at one end and connected to each other at their opposite end, and each of these blocks may be moulded with a hole extending longitudinally from the free end towards the connected end to receive a plant element. |
