Application of Plywood with Water-Based Phenol-Formaldehyde Resin Impregnated Linerboards as Formwork for Concrete Structure

Abstract

The front and back layers of plywood formwork consist of veneers made of Oceania timber (Shorea spp.). As the demand for Oceania timber has increased worldwide, it has become difficult to find good front and back layers for plywood. This study, therefore, has investigated plywood made with water-based phenolformaldehyde (PF) resin impregnated linerboards of different basis weights and pulp types. Manufactured plywood with water-based PF resin impregnated linerboards made of Korean recycled linerboard pulp layers, which were pressed at 140 degrees C and 10 kg/cm(2) for 3 min, had the highest internal bond strength(.) Furthermore, the internal bond strength of plywood with K2 linerboard was highest among all those tested. Based on the results of heat and cold cycle tests, alkali tests, abrasion tests, and boiling water tests, three types of linerboards: K2, KAC and KLB were found to be suitable for plywood formwork. (C) Koninklijke Brill NV, Leiden, 2011