Modification in durability of mango wood through reactive reinforcement of polyacrylonitrile

Abstract

Reactive reinforcement of polyacrylonitrile (PAN) into mango wood (MW) has afforded a series of wood polymer composites (WPCs) with improved mechanical properties, resistance against solvents, chemicals and biodegradation. The process of reactive reinforcement of PAN into MW was conducted through treatment of leached MW panels with a composition of acrylonitrile (AN, 20–60 v/v) and 2,2-azobisisobutyronitrile (1 wt%) in dimethyl formamide over 12 h under ambient conditions followed by curing at 95 ± 1 °C over additional 6 h. This has afforded a series of WPCs with PAN loading in the range of 5.5 to 15.0. Scanning electron microscopy in combination with wood content data reveals the loading (wt%) of PAN into the matrix of MW. PAN loading of 8.85 wt% was found optimum towards enhancing the compressive, impact and static bending strength of WPCs. PAN loading has raised the resistance of WPCs in organic solvents, hot water and aqueous NaOH. WPC with PAN loading of 15 wt% has shown enhanced resistance against biodegradation in presence of a decay fungus Coriolous versicolor. This has been revealed through the controlled release of protein, reducing sugar contents and enzyme activities in presence of a decay fungus under incubation over 168 hr. The present investigation reveals a viable method of reinforcement of PAN into MW to achieve the WPCs with improved strength, stability in degrading chemicals, controlled biodegragation.