Improved and novel surface fluorinated products

The use of surface fluorination negates the necessity for using adhesive pr omoters to achieve adequate paint adhesion on polyolefinic substrates, even for water-based paints. The addition of oxyfluorinated polypropylene (PP) fibres to cementitious mixtures enhances properties like wet and dry crack control, impact resistance, water absorption etc. This is due to the improv ed adhesion between oxyfluorinated fibres and cement. A new surface fluorin ation method for high-density polyethylene (HDPE) enhances petrol barrier p roperties to a permeation rate lower than that of fluoropolymers. To scrub unreacted F-2 and gaseous reaction products like HF formed during the surfa ce fluorination process, the use of wet limestone is suggested. (C) 2000 El sevier Science S.A. All rights reserved.