Properties of hardener-free epoxy-modified mortars utilizing pyrolysis tar replacement

摘要

This study focused on the performance of hardener-free epoxy-modified mortar (HFEMM) with pyrolysis tar (PT), a by-product of the green wood industry. HFEMMs were prepared with amounts of 1, 3, and 5% epoxy resin. For the HFEMM with a 1% epoxy resin mixing rate, 5,10, 15, and 20% of the epoxy resin were replaced with PT. The highest hardening rate was observed for the HFEMM with 1% epoxy resin, whereas the amounts of hardened and unhardened epoxy resin were the largest at 5%. When 1% epoxy resin was replaced with PT, the hardening rate increased to 10%. When 10% PT was substituted with 1% epoxy resin, the compressive, flexural, and adhesive strengths increased because of the higher hardening rate. X-ray diffraction result showed that an increase in the epoxy resin content and the PT replacement rates resulted in lower amounts of calcium hydroxide and lower semi-adiabatic and maximum exothermic temperatures. These results showed that the use of PT in the HFEMM could improve its performance while providing an avenue to recycle PT. (C) 2017 Published by Elsevier Ltd.