Put rubber gloves on and clean the damaged plastic on the recliner with a cloth using acetone. Once the damaged plastic is free of dust and dirt, allow the acetone to evaporate.
Spread urethane-silicone resin over the crack with a plastic spatula. Use the spatula to make the urethane-silicone resin smooth and flush. Let the resin dry for about three hours, or as long as directed by the manufacturer.
Sand the urethane-silicone resin patch with 360-grit sandpaper to make it blend with the surface of the plastic. Wipe clean using a tack cloth.
Squirt a mild liquid detergent onto a clean sponge. Wet the sponge and clean the plastic convenience on the recliner. Rinse with plain water thereafter and let air dry.